Browse Source
* changes: daemon: Add --ketch=LEADER flag Ketch: Intercept push and route it through Ketch Ketch: Simple map of running leader instances Ketch: Basic replication systemstable-4.3
Shawn Pearce
9 years ago
committed by
Gerrit Code Review @ Eclipse.org
27 changed files with 5022 additions and 1 deletions
@ -0,0 +1,13 @@
|
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accepted=accepted. |
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cannotFetchFromLocalReplica=cannot fetch from LocalReplica |
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failed=failed! |
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invalidFollowerUri=invalid follower URI |
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leaderFailedToStore=leader failed to store |
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localReplicaRequired=LocalReplica instance is required |
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mismatchedTxnNamespace=mismatched txnNamespace; expected {0} found {1} |
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outsideTxnNamespace=ref {0} is outside of txnNamespace {1} |
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proposingUpdates=Proposing updates |
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queuedProposalFailedToApply=queued proposal failed to apply |
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starting=starting! |
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unsupportedVoterCount=unsupported voter count {0}, expected one of {1} |
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waitingForQueue=Waiting for queue |
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@ -0,0 +1,141 @@
|
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/* |
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* Copyright (C) 2016, Google Inc. |
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* and other copyright owners as documented in the project's IP log. |
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* |
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* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
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* |
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* All rights reserved. |
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* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
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* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
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|
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package org.eclipse.jgit.internal.ketch; |
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|
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import static org.eclipse.jgit.internal.ketch.KetchConstants.TERM; |
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|
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import java.io.IOException; |
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import java.util.List; |
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|
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import org.eclipse.jgit.lib.CommitBuilder; |
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import org.eclipse.jgit.lib.ObjectId; |
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import org.eclipse.jgit.lib.ObjectInserter; |
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import org.eclipse.jgit.lib.Repository; |
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import org.eclipse.jgit.lib.TreeFormatter; |
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import org.eclipse.jgit.revwalk.RevCommit; |
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import org.eclipse.jgit.revwalk.RevWalk; |
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import org.slf4j.Logger; |
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import org.slf4j.LoggerFactory; |
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|
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/** |
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* The initial {@link Round} for a leaderless repository, used to establish a |
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* leader. |
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*/ |
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class ElectionRound extends Round { |
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private static final Logger log = LoggerFactory.getLogger(ElectionRound.class); |
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|
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private long term; |
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|
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ElectionRound(KetchLeader leader, LogIndex head) { |
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super(leader, head); |
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} |
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|
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@Override |
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void start() throws IOException { |
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ObjectId id; |
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try (Repository git = leader.openRepository(); |
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ObjectInserter inserter = git.newObjectInserter()) { |
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id = bumpTerm(git, inserter); |
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inserter.flush(); |
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} |
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runAsync(id); |
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} |
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|
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@Override |
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void success() { |
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// Do nothing upon election, KetchLeader will copy the term.
|
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} |
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|
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long getTerm() { |
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return term; |
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} |
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|
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private ObjectId bumpTerm(Repository git, ObjectInserter inserter) |
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throws IOException { |
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CommitBuilder b = new CommitBuilder(); |
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if (!ObjectId.zeroId().equals(acceptedOldIndex)) { |
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try (RevWalk rw = new RevWalk(git)) { |
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RevCommit c = rw.parseCommit(acceptedOldIndex); |
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b.setTreeId(c.getTree()); |
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b.setParentId(acceptedOldIndex); |
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term = parseTerm(c.getFooterLines(TERM)) + 1; |
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} |
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} else { |
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term = 1; |
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b.setTreeId(inserter.insert(new TreeFormatter())); |
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} |
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|
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StringBuilder msg = new StringBuilder(); |
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msg.append(KetchConstants.TERM.getName()) |
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.append(": ") //$NON-NLS-1$
|
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.append(term); |
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|
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String tag = leader.getSystem().newLeaderTag(); |
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if (tag != null && !tag.isEmpty()) { |
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msg.append(' ').append(tag); |
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} |
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|
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b.setAuthor(leader.getSystem().newCommitter()); |
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b.setCommitter(b.getAuthor()); |
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b.setMessage(msg.toString()); |
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|
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if (log.isDebugEnabled()) { |
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log.debug("Trying to elect myself " + b.getMessage()); //$NON-NLS-1$
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} |
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return inserter.insert(b); |
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} |
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|
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private static long parseTerm(List<String> footer) { |
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if (footer.isEmpty()) { |
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return 0; |
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} |
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|
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String s = footer.get(0); |
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int p = s.indexOf(' '); |
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if (p > 0) { |
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s = s.substring(0, p); |
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} |
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return Long.parseLong(s, 10); |
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} |
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} |
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@ -0,0 +1,82 @@
|
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/* |
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* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
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|
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package org.eclipse.jgit.internal.ketch; |
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|
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import org.eclipse.jgit.revwalk.FooterKey; |
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|
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/** Frequently used constants in a Ketch system. */ |
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public class KetchConstants { |
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/** |
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* Default reference namespace holding {@link #ACCEPTED} and |
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* {@link #COMMITTED} references and the {@link #STAGE} sub-namespace. |
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*/ |
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public static final String DEFAULT_TXN_NAMESPACE = "refs/txn/"; //$NON-NLS-1$
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/** Reference name holding the RefTree accepted by a follower. */ |
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public static final String ACCEPTED = "accepted"; //$NON-NLS-1$
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|
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/** Reference name holding the RefTree known to be committed. */ |
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public static final String COMMITTED = "committed"; //$NON-NLS-1$
|
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|
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/** Reference subdirectory holding proposed heads. */ |
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public static final String STAGE = "stage/"; //$NON-NLS-1$
|
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|
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/** Footer containing the current term. */ |
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public static final FooterKey TERM = new FooterKey("Term"); //$NON-NLS-1$
|
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|
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/** Section for Ketch configuration ({@code ketch}). */ |
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public static final String CONFIG_SECTION_KETCH = "ketch"; //$NON-NLS-1$
|
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|
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/** Behavior for a replica ({@code remote.$name.ketch-type}) */ |
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public static final String CONFIG_KEY_TYPE = "ketch-type"; //$NON-NLS-1$
|
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|
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/** Behavior for a replica ({@code remote.$name.ketch-commit}) */ |
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public static final String CONFIG_KEY_COMMIT = "ketch-commit"; //$NON-NLS-1$
|
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|
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/** Behavior for a replica ({@code remote.$name.ketch-speed}) */ |
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public static final String CONFIG_KEY_SPEED = "ketch-speed"; //$NON-NLS-1$
|
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|
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private KetchConstants() { |
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} |
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} |
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@ -0,0 +1,624 @@
|
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/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
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package org.eclipse.jgit.internal.ketch; |
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|
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import static org.eclipse.jgit.internal.ketch.KetchLeader.State.CANDIDATE; |
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import static org.eclipse.jgit.internal.ketch.KetchLeader.State.LEADER; |
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import static org.eclipse.jgit.internal.ketch.KetchLeader.State.SHUTDOWN; |
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import static org.eclipse.jgit.internal.ketch.KetchReplica.Participation.FOLLOWER_ONLY; |
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import static org.eclipse.jgit.internal.ketch.Proposal.State.QUEUED; |
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|
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import java.io.IOException; |
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import java.text.MessageFormat; |
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import java.util.ArrayList; |
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import java.util.Arrays; |
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import java.util.Collection; |
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import java.util.List; |
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import java.util.concurrent.locks.Lock; |
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import java.util.concurrent.locks.ReentrantLock; |
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|
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import org.eclipse.jgit.internal.storage.reftree.RefTree; |
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import org.eclipse.jgit.lib.ObjectId; |
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import org.eclipse.jgit.lib.Repository; |
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import org.eclipse.jgit.revwalk.RevCommit; |
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import org.eclipse.jgit.revwalk.RevWalk; |
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import org.slf4j.Logger; |
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import org.slf4j.LoggerFactory; |
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|
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/** |
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* A leader managing consensus across remote followers. |
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* <p> |
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* A leader instance starts up in {@link State#CANDIDATE} and tries to begin a |
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* new term by sending an {@link ElectionRound} to all replicas. Its term starts |
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* if a majority of replicas have accepted this leader instance for the term. |
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* <p> |
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* Once elected by a majority the instance enters {@link State#LEADER} and runs |
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* proposals offered to {@link #queueProposal(Proposal)}. This continues until |
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* the leader is timed out for inactivity, or is deposed by a competing leader |
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* gaining its own majority. |
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* <p> |
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* Once timed out or deposed this {@code KetchLeader} instance should be |
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* discarded, and a new instance takes over. |
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* <p> |
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* Each leader instance coordinates a group of {@link KetchReplica}s. Replica |
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* instances are owned by the leader instance and must be discarded when the |
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* leader is discarded. |
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* <p> |
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* In Ketch all push requests are issued through the leader. The steps are as |
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* follows (see {@link KetchPreReceive} for an example): |
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* <ul> |
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* <li>Create a {@link Proposal} with the |
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* {@link org.eclipse.jgit.transport.ReceiveCommand}s that represent the push. |
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* <li>Invoke {@link #queueProposal(Proposal)} on the leader instance. |
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* <li>Wait for consensus with {@link Proposal#await()}. |
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* <li>To examine the status of the push, check {@link Proposal#getCommands()}, |
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* looking at |
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* {@link org.eclipse.jgit.internal.storage.reftree.Command#getResult()}. |
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* </ul> |
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* <p> |
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* The leader gains consensus by first pushing the needed objects and a |
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* {@link RefTree} representing the desired target repository state to the |
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* {@code refs/txn/accepted} branch on each of the replicas. Once a majority has |
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* succeeded, the leader commits the state by either pushing the |
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* {@code refs/txn/accepted} value to {@code refs/txn/committed} (for |
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* Ketch-aware replicas) or by pushing updates to {@code refs/heads/master}, |
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* etc. for stock Git replicas. |
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* <p> |
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* Internally, the actual transport to replicas is performed on background |
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* threads via the {@link KetchSystem}'s executor service. For performance, the |
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* {@link KetchLeader}, {@link KetchReplica} and {@link Proposal} objects share |
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* some state, and may invoke each other's methods on different threads. This |
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* access is protected by the leader's {@link #lock} object. Care must be taken |
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* to prevent concurrent access by correctly obtaining the leader's lock. |
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*/ |
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public abstract class KetchLeader { |
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private static final Logger log = LoggerFactory.getLogger(KetchLeader.class); |
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|
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/** Current state of the leader instance. */ |
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public static enum State { |
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/** Newly created instance trying to elect itself leader. */ |
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CANDIDATE, |
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|
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/** Leader instance elected by a majority. */ |
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LEADER, |
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|
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/** Instance has been deposed by another with a more recent term. */ |
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DEPOSED, |
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|
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/** Leader has been gracefully shutdown, e.g. due to inactivity. */ |
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SHUTDOWN; |
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} |
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|
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private final KetchSystem system; |
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|
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/** Leader's knowledge of replicas for this repository. */ |
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private KetchReplica[] voters; |
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private KetchReplica[] followers; |
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private LocalReplica self; |
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|
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/** |
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* Lock protecting all data within this leader instance. |
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* <p> |
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* This lock extends into the {@link KetchReplica} instances used by the |
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* leader. They share the same lock instance to simplify concurrency. |
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*/ |
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final Lock lock; |
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|
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private State state = CANDIDATE; |
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|
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/** Term of this leader, once elected. */ |
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private long term; |
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|
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/** |
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* Pending proposals accepted into the queue in FIFO order. |
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* <p> |
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* These proposals were preflighted and do not contain any conflicts with |
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* each other and their expectations matched the leader's local view of the |
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* agreed upon {@code refs/txn/accepted} tree. |
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*/ |
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private final List<Proposal> queued; |
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|
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/** |
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* State of the repository's RefTree after applying all entries in |
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* {@link #queued}. New proposals must be consistent with this tree to be |
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* appended to the end of {@link #queued}. |
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* <p> |
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* Must be deep-copied with {@link RefTree#copy()} if |
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* {@link #roundHoldsReferenceToRefTree} is {@code true}. |
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*/ |
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private RefTree refTree; |
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|
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/** |
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* If {@code true} {@link #refTree} must be duplicated before queuing the |
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* next proposal. The {@link #refTree} was passed into the constructor of a |
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* {@link ProposalRound}, and that external reference to the {@link RefTree} |
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* object is held by the proposal until it materializes the tree object in |
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* the object store. This field is set {@code true} when the proposal begins |
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* execution and set {@code false} once tree objects are persisted in the |
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* local repository's object store or {@link #refTree} is replaced with a |
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* copy to isolate it from any running rounds. |
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* <p> |
||||
* If proposals arrive less frequently than the {@code RefTree} is written |
||||
* out to the repository the {@link #roundHoldsReferenceToRefTree} behavior |
||||
* avoids duplicating {@link #refTree}, reducing both time and memory used. |
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* However if proposals arrive more frequently {@link #refTree} must be |
||||
* duplicated to prevent newly queued proposals from corrupting the |
||||
* {@link #runningRound}. |
||||
*/ |
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volatile boolean roundHoldsReferenceToRefTree; |
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|
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/** End of the leader's log. */ |
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private LogIndex headIndex; |
||||
|
||||
/** Leader knows this (and all prior) states are committed. */ |
||||
private LogIndex committedIndex; |
||||
|
||||
/** |
||||
* Is the leader idle with no work pending? If {@code true} there is no work |
||||
* for the leader (normal state). This field is {@code false} when the |
||||
* leader thread is scheduled for execution, or while {@link #runningRound} |
||||
* defines a round in progress. |
||||
*/ |
||||
private boolean idle; |
||||
|
||||
/** Current round the leader is preparing and waiting for a vote on. */ |
||||
private Round runningRound; |
||||
|
||||
/** |
||||
* Construct a leader for a Ketch instance. |
||||
* |
||||
* @param system |
||||
* Ketch system configuration the leader must adhere to. |
||||
*/ |
||||
protected KetchLeader(KetchSystem system) { |
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this.system = system; |
||||
this.lock = new ReentrantLock(true /* fair */); |
||||
this.queued = new ArrayList<>(4); |
||||
this.idle = true; |
||||
} |
||||
|
||||
/** @return system configuration. */ |
||||
KetchSystem getSystem() { |
||||
return system; |
||||
} |
||||
|
||||
/** |
||||
* Configure the replicas used by this Ketch instance. |
||||
* <p> |
||||
* Replicas should be configured once at creation before any proposals are |
||||
* executed. Once elections happen, <b>reconfiguration is a complicated |
||||
* concept that is not currently supported</b>. |
||||
* |
||||
* @param replicas |
||||
* members participating with the same repository. |
||||
*/ |
||||
public void setReplicas(Collection<KetchReplica> replicas) { |
||||
List<KetchReplica> v = new ArrayList<>(5); |
||||
List<KetchReplica> f = new ArrayList<>(5); |
||||
for (KetchReplica r : replicas) { |
||||
switch (r.getParticipation()) { |
||||
case FULL: |
||||
v.add(r); |
||||
break; |
||||
|
||||
case FOLLOWER_ONLY: |
||||
f.add(r); |
||||
break; |
||||
} |
||||
} |
||||
|
||||
Collection<Integer> validVoters = validVoterCounts(); |
||||
if (!validVoters.contains(Integer.valueOf(v.size()))) { |
||||
throw new IllegalArgumentException(MessageFormat.format( |
||||
KetchText.get().unsupportedVoterCount, |
||||
Integer.valueOf(v.size()), |
||||
validVoters)); |
||||
} |
||||
|
||||
LocalReplica me = findLocal(v); |
||||
if (me == null) { |
||||
throw new IllegalArgumentException( |
||||
KetchText.get().localReplicaRequired); |
||||
} |
||||
|
||||
lock.lock(); |
||||
try { |
||||
voters = v.toArray(new KetchReplica[v.size()]); |
||||
followers = f.toArray(new KetchReplica[f.size()]); |
||||
self = me; |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
private static Collection<Integer> validVoterCounts() { |
||||
@SuppressWarnings("boxing") |
||||
Integer[] valid = { |
||||
// An odd number of voting replicas is required.
|
||||
1, 3, 5, 7, 9 }; |
||||
return Arrays.asList(valid); |
||||
} |
||||
|
||||
private static LocalReplica findLocal(Collection<KetchReplica> voters) { |
||||
for (KetchReplica r : voters) { |
||||
if (r instanceof LocalReplica) { |
||||
return (LocalReplica) r; |
||||
} |
||||
} |
||||
return null; |
||||
} |
||||
|
||||
/** |
||||
* Get an instance of the repository for use by a leader thread. |
||||
* <p> |
||||
* The caller will close the repository. |
||||
* |
||||
* @return opened repository for use by the leader thread. |
||||
* @throws IOException |
||||
* cannot reopen the repository for the leader. |
||||
*/ |
||||
protected abstract Repository openRepository() throws IOException; |
||||
|
||||
/** |
||||
* Queue a reference update proposal for consensus. |
||||
* <p> |
||||
* This method does not wait for consensus to be reached. The proposal is |
||||
* checked to look for risks of conflicts, and then submitted into the queue |
||||
* for distribution as soon as possible. |
||||
* <p> |
||||
* Callers must use {@link Proposal#await()} to see if the proposal is done. |
||||
* |
||||
* @param proposal |
||||
* the proposed reference updates to queue for consideration. |
||||
* Once execution is complete the individual reference result |
||||
* fields will be populated with the outcome. |
||||
* @throws InterruptedException |
||||
* current thread was interrupted. The proposal may have been |
||||
* aborted if it was not yet queued for execution. |
||||
* @throws IOException |
||||
* unrecoverable error preventing proposals from being attempted |
||||
* by this leader. |
||||
*/ |
||||
public void queueProposal(Proposal proposal) |
||||
throws InterruptedException, IOException { |
||||
try { |
||||
lock.lockInterruptibly(); |
||||
} catch (InterruptedException e) { |
||||
proposal.abort(); |
||||
throw e; |
||||
} |
||||
try { |
||||
if (refTree == null) { |
||||
initialize(); |
||||
for (Proposal p : queued) { |
||||
refTree.apply(p.getCommands()); |
||||
} |
||||
} else if (roundHoldsReferenceToRefTree) { |
||||
refTree = refTree.copy(); |
||||
roundHoldsReferenceToRefTree = false; |
||||
} |
||||
|
||||
if (!refTree.apply(proposal.getCommands())) { |
||||
// A conflict exists so abort the proposal.
|
||||
proposal.abort(); |
||||
return; |
||||
} |
||||
|
||||
queued.add(proposal); |
||||
proposal.notifyState(QUEUED); |
||||
|
||||
if (idle) { |
||||
scheduleLeader(); |
||||
} |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
private void initialize() throws IOException { |
||||
try (Repository git = openRepository(); RevWalk rw = new RevWalk(git)) { |
||||
self.initialize(git); |
||||
|
||||
ObjectId accepted = self.getTxnAccepted(); |
||||
if (!ObjectId.zeroId().equals(accepted)) { |
||||
RevCommit c = rw.parseCommit(accepted); |
||||
headIndex = LogIndex.unknown(accepted); |
||||
refTree = RefTree.read(rw.getObjectReader(), c.getTree()); |
||||
} else { |
||||
headIndex = LogIndex.unknown(ObjectId.zeroId()); |
||||
refTree = RefTree.newEmptyTree(); |
||||
} |
||||
} |
||||
} |
||||
|
||||
private void scheduleLeader() { |
||||
idle = false; |
||||
system.getExecutor().execute(new Runnable() { |
||||
@Override |
||||
public void run() { |
||||
runLeader(); |
||||
} |
||||
}); |
||||
} |
||||
|
||||
private void runLeader() { |
||||
Round round; |
||||
lock.lock(); |
||||
try { |
||||
switch (state) { |
||||
case CANDIDATE: |
||||
round = new ElectionRound(this, headIndex); |
||||
break; |
||||
|
||||
case LEADER: |
||||
round = newProposalRound(); |
||||
break; |
||||
|
||||
case DEPOSED: |
||||
case SHUTDOWN: |
||||
default: |
||||
log.warn("Leader cannot run {}", state); //$NON-NLS-1$
|
||||
// TODO(sop): Redirect proposals.
|
||||
return; |
||||
} |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
|
||||
try { |
||||
round.start(); |
||||
} catch (IOException e) { |
||||
// TODO(sop) Depose leader if it cannot use its repository.
|
||||
log.error(KetchText.get().leaderFailedToStore, e); |
||||
lock.lock(); |
||||
try { |
||||
nextRound(); |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
} |
||||
|
||||
private ProposalRound newProposalRound() { |
||||
List<Proposal> todo = new ArrayList<>(queued); |
||||
queued.clear(); |
||||
roundHoldsReferenceToRefTree = true; |
||||
return new ProposalRound(this, headIndex, todo, refTree); |
||||
} |
||||
|
||||
/** @return term of this leader's reign. */ |
||||
long getTerm() { |
||||
return term; |
||||
} |
||||
|
||||
/** @return end of the leader's log. */ |
||||
LogIndex getHead() { |
||||
return headIndex; |
||||
} |
||||
|
||||
/** |
||||
* @return state leader knows it has committed across a quorum of replicas. |
||||
*/ |
||||
LogIndex getCommitted() { |
||||
return committedIndex; |
||||
} |
||||
|
||||
boolean isIdle() { |
||||
return idle; |
||||
} |
||||
|
||||
void runAsync(Round round) { |
||||
lock.lock(); |
||||
try { |
||||
// End of the log is this round. Once transport begins it is
|
||||
// reasonable to assume at least one replica will eventually get
|
||||
// this, and there is reasonable probability it commits.
|
||||
headIndex = round.acceptedNewIndex; |
||||
runningRound = round; |
||||
|
||||
for (KetchReplica replica : voters) { |
||||
replica.pushTxnAcceptedAsync(round); |
||||
} |
||||
for (KetchReplica replica : followers) { |
||||
replica.pushTxnAcceptedAsync(round); |
||||
} |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Asynchronous signal from a replica after completion. |
||||
* <p> |
||||
* Must be called while {@link #lock} is held by the replica. |
||||
* |
||||
* @param replica |
||||
* replica posting a completion event. |
||||
*/ |
||||
void onReplicaUpdate(KetchReplica replica) { |
||||
if (log.isDebugEnabled()) { |
||||
log.debug("Replica {} finished:\n{}", //$NON-NLS-1$
|
||||
replica.describeForLog(), snapshot()); |
||||
} |
||||
|
||||
if (replica.getParticipation() == FOLLOWER_ONLY) { |
||||
// Followers cannot vote, so votes haven't changed.
|
||||
return; |
||||
} else if (runningRound == null) { |
||||
// No round running, no need to tally votes.
|
||||
return; |
||||
} |
||||
|
||||
assert headIndex.equals(runningRound.acceptedNewIndex); |
||||
int matching = 0; |
||||
for (KetchReplica r : voters) { |
||||
if (r.hasAccepted(headIndex)) { |
||||
matching++; |
||||
} |
||||
} |
||||
|
||||
int quorum = voters.length / 2 + 1; |
||||
boolean success = matching >= quorum; |
||||
if (!success) { |
||||
return; |
||||
} |
||||
|
||||
switch (state) { |
||||
case CANDIDATE: |
||||
term = ((ElectionRound) runningRound).getTerm(); |
||||
state = LEADER; |
||||
if (log.isDebugEnabled()) { |
||||
log.debug("Won election, running term " + term); //$NON-NLS-1$
|
||||
} |
||||
|
||||
//$FALL-THROUGH$
|
||||
case LEADER: |
||||
committedIndex = headIndex; |
||||
if (log.isDebugEnabled()) { |
||||
log.debug("Committed {} in term {}", //$NON-NLS-1$
|
||||
committedIndex.describeForLog(), |
||||
Long.valueOf(term)); |
||||
} |
||||
nextRound(); |
||||
commitAsync(replica); |
||||
notifySuccess(runningRound); |
||||
if (log.isDebugEnabled()) { |
||||
log.debug("Leader state:\n{}", snapshot()); //$NON-NLS-1$
|
||||
} |
||||
break; |
||||
|
||||
default: |
||||
log.debug("Leader ignoring replica while in {}", state); //$NON-NLS-1$
|
||||
break; |
||||
} |
||||
} |
||||
|
||||
private void notifySuccess(Round round) { |
||||
// Drop the leader lock while notifying Proposal listeners.
|
||||
lock.unlock(); |
||||
try { |
||||
round.success(); |
||||
} finally { |
||||
lock.lock(); |
||||
} |
||||
} |
||||
|
||||
private void commitAsync(KetchReplica caller) { |
||||
for (KetchReplica r : voters) { |
||||
if (r == caller) { |
||||
continue; |
||||
} |
||||
if (r.shouldPushUnbatchedCommit(committedIndex, isIdle())) { |
||||
r.pushCommitAsync(committedIndex); |
||||
} |
||||
} |
||||
for (KetchReplica r : followers) { |
||||
if (r == caller) { |
||||
continue; |
||||
} |
||||
if (r.shouldPushUnbatchedCommit(committedIndex, isIdle())) { |
||||
r.pushCommitAsync(committedIndex); |
||||
} |
||||
} |
||||
} |
||||
|
||||
/** Schedule the next round; invoked while {@link #lock} is held. */ |
||||
void nextRound() { |
||||
runningRound = null; |
||||
|
||||
if (queued.isEmpty()) { |
||||
idle = true; |
||||
} else { |
||||
// Caller holds lock. Reschedule leader on a new thread so
|
||||
// the call stack can unwind and lock is not held unexpectedly
|
||||
// during prepare for the next round.
|
||||
scheduleLeader(); |
||||
} |
||||
} |
||||
|
||||
/** @return snapshot this leader. */ |
||||
public LeaderSnapshot snapshot() { |
||||
lock.lock(); |
||||
try { |
||||
LeaderSnapshot s = new LeaderSnapshot(); |
||||
s.state = state; |
||||
s.term = term; |
||||
s.headIndex = headIndex; |
||||
s.committedIndex = committedIndex; |
||||
s.idle = isIdle(); |
||||
for (KetchReplica r : voters) { |
||||
s.replicas.add(r.snapshot()); |
||||
} |
||||
for (KetchReplica r : followers) { |
||||
s.replicas.add(r.snapshot()); |
||||
} |
||||
return s; |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
/** Gracefully shutdown this leader and cancel outstanding operations. */ |
||||
public void shutdown() { |
||||
lock.lock(); |
||||
try { |
||||
if (state != SHUTDOWN) { |
||||
state = SHUTDOWN; |
||||
for (KetchReplica r : voters) { |
||||
r.shutdown(); |
||||
} |
||||
for (KetchReplica r : followers) { |
||||
r.shutdown(); |
||||
} |
||||
} |
||||
} finally { |
||||
lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
@Override |
||||
public String toString() { |
||||
return snapshot().toString(); |
||||
} |
||||
} |
||||
@ -0,0 +1,126 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import java.net.URISyntaxException; |
||||
import java.util.concurrent.ConcurrentHashMap; |
||||
import java.util.concurrent.ConcurrentMap; |
||||
import java.util.concurrent.locks.Lock; |
||||
import java.util.concurrent.locks.ReentrantLock; |
||||
|
||||
import org.eclipse.jgit.internal.storage.dfs.DfsRepository; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
|
||||
/** |
||||
* A cache of live leader instances, keyed by repository. |
||||
* <p> |
||||
* Ketch only assigns a leader to a repository when needed. If |
||||
* {@link #get(Repository)} is called for a repository that does not have a |
||||
* leader, the leader is created and added to the cache. |
||||
*/ |
||||
public class KetchLeaderCache { |
||||
private final KetchSystem system; |
||||
private final ConcurrentMap<String, KetchLeader> leaders; |
||||
private final Lock startLock; |
||||
|
||||
/** |
||||
* Initialize a new leader cache. |
||||
* |
||||
* @param system |
||||
* system configuration for the leaders |
||||
*/ |
||||
public KetchLeaderCache(KetchSystem system) { |
||||
this.system = system; |
||||
leaders = new ConcurrentHashMap<>(); |
||||
startLock = new ReentrantLock(true /* fair */); |
||||
} |
||||
|
||||
/** |
||||
* Lookup the leader instance for a given repository. |
||||
* |
||||
* @param repo |
||||
* repository to get the leader for. |
||||
* @return the leader instance for the repository. |
||||
* @throws URISyntaxException |
||||
* remote configuration contains an invalid URL. |
||||
*/ |
||||
public KetchLeader get(Repository repo) |
||||
throws URISyntaxException { |
||||
String key = computeKey(repo); |
||||
KetchLeader leader = leaders.get(key); |
||||
if (leader != null) { |
||||
return leader; |
||||
} |
||||
return startLeader(key, repo); |
||||
} |
||||
|
||||
private KetchLeader startLeader(String key, Repository repo) |
||||
throws URISyntaxException { |
||||
startLock.lock(); |
||||
try { |
||||
KetchLeader leader = leaders.get(key); |
||||
if (leader != null) { |
||||
return leader; |
||||
} |
||||
leader = system.createLeader(repo); |
||||
leaders.put(key, leader); |
||||
return leader; |
||||
} finally { |
||||
startLock.unlock(); |
||||
} |
||||
} |
||||
|
||||
private static String computeKey(Repository repo) { |
||||
if (repo instanceof DfsRepository) { |
||||
DfsRepository dfs = (DfsRepository) repo; |
||||
return dfs.getDescription().getRepositoryName(); |
||||
} |
||||
|
||||
if (repo.getDirectory() != null) { |
||||
return repo.getDirectory().toURI().toString(); |
||||
} |
||||
|
||||
throw new IllegalArgumentException(); |
||||
} |
||||
} |
||||
@ -0,0 +1,155 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
||||
import static java.util.concurrent.TimeUnit.SECONDS; |
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.EXECUTED; |
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.QUEUED; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.NOT_ATTEMPTED; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.REJECTED_OTHER_REASON; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.Collection; |
||||
|
||||
import org.eclipse.jgit.internal.JGitText; |
||||
import org.eclipse.jgit.transport.PreReceiveHook; |
||||
import org.eclipse.jgit.transport.ProgressSpinner; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
import org.eclipse.jgit.transport.ReceivePack; |
||||
import org.slf4j.Logger; |
||||
import org.slf4j.LoggerFactory; |
||||
|
||||
/** |
||||
* PreReceiveHook for handling push traffic in a Ketch system. |
||||
* <p> |
||||
* Install an instance on {@link ReceivePack} to capture the commands and other |
||||
* connection state and relay them through the {@link KetchLeader}, allowing the |
||||
* leader to gain consensus about the new reference state. |
||||
*/ |
||||
public class KetchPreReceive implements PreReceiveHook { |
||||
private static final Logger log = LoggerFactory.getLogger(KetchPreReceive.class); |
||||
|
||||
private final KetchLeader leader; |
||||
|
||||
/** |
||||
* Construct a hook executing updates through a {@link KetchLeader}. |
||||
* |
||||
* @param leader |
||||
* leader for this repository. |
||||
*/ |
||||
public KetchPreReceive(KetchLeader leader) { |
||||
this.leader = leader; |
||||
} |
||||
|
||||
@Override |
||||
public void onPreReceive(ReceivePack rp, Collection<ReceiveCommand> cmds) { |
||||
cmds = ReceiveCommand.filter(cmds, NOT_ATTEMPTED); |
||||
if (cmds.isEmpty()) { |
||||
return; |
||||
} |
||||
|
||||
try { |
||||
Proposal proposal = new Proposal(rp.getRevWalk(), cmds) |
||||
.setPushCertificate(rp.getPushCertificate()) |
||||
.setAuthor(rp.getRefLogIdent()) |
||||
.setMessage("push"); //$NON-NLS-1$
|
||||
leader.queueProposal(proposal); |
||||
if (proposal.isDone()) { |
||||
// This failed fast, e.g. conflict or bad precondition.
|
||||
return; |
||||
} |
||||
|
||||
ProgressSpinner spinner = new ProgressSpinner( |
||||
rp.getMessageOutputStream()); |
||||
if (proposal.getState() == QUEUED) { |
||||
waitForQueue(proposal, spinner); |
||||
} |
||||
if (!proposal.isDone()) { |
||||
waitForPropose(proposal, spinner); |
||||
} |
||||
} catch (IOException | InterruptedException e) { |
||||
String msg = JGitText.get().transactionAborted; |
||||
for (ReceiveCommand cmd : cmds) { |
||||
if (cmd.getResult() == NOT_ATTEMPTED) { |
||||
cmd.setResult(REJECTED_OTHER_REASON, msg); |
||||
} |
||||
} |
||||
log.error(msg, e); |
||||
} |
||||
} |
||||
|
||||
private void waitForQueue(Proposal proposal, ProgressSpinner spinner) |
||||
throws InterruptedException { |
||||
spinner.beginTask(KetchText.get().waitingForQueue, 1, SECONDS); |
||||
while (!proposal.awaitStateChange(QUEUED, 250, MILLISECONDS)) { |
||||
spinner.update(); |
||||
} |
||||
switch (proposal.getState()) { |
||||
case RUNNING: |
||||
default: |
||||
spinner.endTask(KetchText.get().starting); |
||||
break; |
||||
|
||||
case EXECUTED: |
||||
spinner.endTask(KetchText.get().accepted); |
||||
break; |
||||
|
||||
case ABORTED: |
||||
spinner.endTask(KetchText.get().failed); |
||||
break; |
||||
} |
||||
} |
||||
|
||||
private void waitForPropose(Proposal proposal, ProgressSpinner spinner) |
||||
throws InterruptedException { |
||||
spinner.beginTask(KetchText.get().proposingUpdates, 2, SECONDS); |
||||
while (!proposal.await(250, MILLISECONDS)) { |
||||
spinner.update(); |
||||
} |
||||
spinner.endTask(proposal.getState() == EXECUTED |
||||
? KetchText.get().accepted |
||||
: KetchText.get().failed); |
||||
} |
||||
} |
||||
@ -0,0 +1,755 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.CommitSpeed.BATCHED; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.CommitSpeed.FAST; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.CURRENT; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.LAGGING; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.OFFLINE; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.UNKNOWN; |
||||
import static org.eclipse.jgit.lib.Constants.HEAD; |
||||
import static org.eclipse.jgit.lib.FileMode.TYPE_GITLINK; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.NOT_ATTEMPTED; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.OK; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Type.CREATE; |
||||
|
||||
import java.io.IOException; |
||||
import java.lang.ref.WeakReference; |
||||
import java.util.ArrayList; |
||||
import java.util.Collection; |
||||
import java.util.HashMap; |
||||
import java.util.Iterator; |
||||
import java.util.List; |
||||
import java.util.Map; |
||||
import java.util.concurrent.Callable; |
||||
import java.util.concurrent.Future; |
||||
|
||||
import org.eclipse.jgit.annotations.NonNull; |
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.internal.storage.reftree.RefTree; |
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
import org.eclipse.jgit.treewalk.TreeWalk; |
||||
import org.eclipse.jgit.util.SystemReader; |
||||
import org.slf4j.Logger; |
||||
import org.slf4j.LoggerFactory; |
||||
|
||||
/** |
||||
* A Ketch replica, either {@link LocalReplica} or {@link RemoteGitReplica}. |
||||
* <p> |
||||
* Replicas can be either a stock Git replica, or a Ketch-aware replica. |
||||
* <p> |
||||
* A stock Git replica has no special knowledge of Ketch and simply stores |
||||
* objects and references. Ketch communicates with the stock Git replica using |
||||
* the Git push wire protocol. The {@link KetchLeader} commits an agreed upon |
||||
* state by pushing all references to the Git replica, for example |
||||
* {@code "refs/heads/master"} is pushed during commit. Stock Git replicas use |
||||
* {@link CommitMethod#ALL_REFS} to record the final state. |
||||
* <p> |
||||
* Ketch-aware replicas understand the {@code RefTree} sent during the proposal |
||||
* and during commit are able to update their own reference space to match the |
||||
* state represented by the {@code RefTree}. Ketch-aware replicas typically use |
||||
* a {@link org.eclipse.jgit.internal.storage.reftree.RefTreeDatabase} and |
||||
* {@link CommitMethod#TXN_COMMITTED} to record the final state. |
||||
* <p> |
||||
* KetchReplica instances are tightly coupled with a single {@link KetchLeader}. |
||||
* Some state may be accessed by the leader thread and uses the leader's own |
||||
* {@link KetchLeader#lock} to protect shared data. |
||||
*/ |
||||
public abstract class KetchReplica { |
||||
static final Logger log = LoggerFactory.getLogger(KetchReplica.class); |
||||
private static final byte[] PEEL = { ' ', '^' }; |
||||
|
||||
/** Participation of a replica in establishing consensus. */ |
||||
public enum Participation { |
||||
/** Replica can vote. */ |
||||
FULL, |
||||
|
||||
/** Replica does not vote, but tracks leader. */ |
||||
FOLLOWER_ONLY; |
||||
} |
||||
|
||||
/** How this replica wants to receive Ketch commit operations. */ |
||||
public enum CommitMethod { |
||||
/** All references are pushed to the peer as standard Git. */ |
||||
ALL_REFS, |
||||
|
||||
/** Only {@code refs/txn/committed} is written/updated. */ |
||||
TXN_COMMITTED; |
||||
} |
||||
|
||||
/** Delay before committing to a replica. */ |
||||
public enum CommitSpeed { |
||||
/** |
||||
* Send the commit immediately, even if it could be batched with the |
||||
* next proposal. |
||||
*/ |
||||
FAST, |
||||
|
||||
/** |
||||
* If the next proposal is available, batch the commit with it, |
||||
* otherwise just send the commit. This generates less network use, but |
||||
* may provide slower consistency on the replica. |
||||
*/ |
||||
BATCHED; |
||||
} |
||||
|
||||
/** Current state of a replica. */ |
||||
public enum State { |
||||
/** Leader has not yet contacted the replica. */ |
||||
UNKNOWN, |
||||
|
||||
/** Replica is behind the consensus. */ |
||||
LAGGING, |
||||
|
||||
/** Replica matches the consensus. */ |
||||
CURRENT, |
||||
|
||||
/** Replica has a different (or unknown) history. */ |
||||
DIVERGENT, |
||||
|
||||
/** Replica's history contains the leader's history. */ |
||||
AHEAD, |
||||
|
||||
/** Replica can not be contacted. */ |
||||
OFFLINE; |
||||
} |
||||
|
||||
private final KetchLeader leader; |
||||
private final String replicaName; |
||||
private final Participation participation; |
||||
private final CommitMethod commitMethod; |
||||
private final CommitSpeed commitSpeed; |
||||
private final long minRetryMillis; |
||||
private final long maxRetryMillis; |
||||
private final Map<ObjectId, List<ReceiveCommand>> staged; |
||||
private final Map<String, ReceiveCommand> running; |
||||
private final Map<String, ReceiveCommand> waiting; |
||||
private final List<ReplicaPushRequest> queued; |
||||
|
||||
/** |
||||
* Value known for {@code "refs/txn/accepted"}. |
||||
* <p> |
||||
* Raft literature refers to this as {@code matchIndex}. |
||||
*/ |
||||
private ObjectId txnAccepted; |
||||
|
||||
/** |
||||
* Value known for {@code "refs/txn/committed"}. |
||||
* <p> |
||||
* Raft literature refers to this as {@code commitIndex}. In traditional |
||||
* Raft this is a state variable inside the follower implementation, but |
||||
* Ketch keeps it in the leader. |
||||
*/ |
||||
private ObjectId txnCommitted; |
||||
|
||||
/** What is happening with this replica. */ |
||||
private State state = UNKNOWN; |
||||
private String error; |
||||
|
||||
/** Scheduled retry due to communication failure. */ |
||||
private Future<?> retryFuture; |
||||
private long lastRetryMillis; |
||||
private long retryAtMillis; |
||||
|
||||
/** |
||||
* Configure a replica representation. |
||||
* |
||||
* @param leader |
||||
* instance this replica follows. |
||||
* @param name |
||||
* unique-ish name identifying this replica for debugging. |
||||
* @param cfg |
||||
* how Ketch should treat the replica. |
||||
*/ |
||||
protected KetchReplica(KetchLeader leader, String name, ReplicaConfig cfg) { |
||||
this.leader = leader; |
||||
this.replicaName = name; |
||||
this.participation = cfg.getParticipation(); |
||||
this.commitMethod = cfg.getCommitMethod(); |
||||
this.commitSpeed = cfg.getCommitSpeed(); |
||||
this.minRetryMillis = cfg.getMinRetry(MILLISECONDS); |
||||
this.maxRetryMillis = cfg.getMaxRetry(MILLISECONDS); |
||||
this.staged = new HashMap<>(); |
||||
this.running = new HashMap<>(); |
||||
this.waiting = new HashMap<>(); |
||||
this.queued = new ArrayList<>(4); |
||||
} |
||||
|
||||
/** @return system configuration. */ |
||||
public KetchSystem getSystem() { |
||||
return getLeader().getSystem(); |
||||
} |
||||
|
||||
/** @return leader instance this replica follows. */ |
||||
public KetchLeader getLeader() { |
||||
return leader; |
||||
} |
||||
|
||||
/** @return unique-ish name for debugging. */ |
||||
public String getName() { |
||||
return replicaName; |
||||
} |
||||
|
||||
/** @return description of this replica for error/debug logging purposes. */ |
||||
protected String describeForLog() { |
||||
return getName(); |
||||
} |
||||
|
||||
/** @return how the replica participates in this Ketch system. */ |
||||
public Participation getParticipation() { |
||||
return participation; |
||||
} |
||||
|
||||
/** @return how Ketch will commit to the repository. */ |
||||
public CommitMethod getCommitMethod() { |
||||
return commitMethod; |
||||
} |
||||
|
||||
/** @return when Ketch will commit to the repository. */ |
||||
public CommitSpeed getCommitSpeed() { |
||||
return commitSpeed; |
||||
} |
||||
|
||||
/** |
||||
* Called by leader to perform graceful shutdown. |
||||
* <p> |
||||
* Default implementation cancels any scheduled retry. Subclasses may add |
||||
* additional logic before or after calling {@code super.shutdown()}. |
||||
* <p> |
||||
* Called with {@link KetchLeader#lock} held by caller. |
||||
*/ |
||||
protected void shutdown() { |
||||
Future<?> f = retryFuture; |
||||
if (f != null) { |
||||
retryFuture = null; |
||||
f.cancel(true); |
||||
} |
||||
} |
||||
|
||||
ReplicaSnapshot snapshot() { |
||||
ReplicaSnapshot s = new ReplicaSnapshot(this); |
||||
s.accepted = txnAccepted; |
||||
s.committed = txnCommitted; |
||||
s.state = state; |
||||
s.error = error; |
||||
s.retryAtMillis = waitingForRetry() ? retryAtMillis : 0; |
||||
return s; |
||||
} |
||||
|
||||
/** |
||||
* Update the leader's view of the replica after a poll. |
||||
* <p> |
||||
* Called with {@link KetchLeader#lock} held by caller. |
||||
* |
||||
* @param refs |
||||
* map of refs from the replica. |
||||
*/ |
||||
void initialize(Map<String, Ref> refs) { |
||||
if (txnAccepted == null) { |
||||
txnAccepted = getId(refs.get(getSystem().getTxnAccepted())); |
||||
} |
||||
if (txnCommitted == null) { |
||||
txnCommitted = getId(refs.get(getSystem().getTxnCommitted())); |
||||
} |
||||
} |
||||
|
||||
ObjectId getTxnAccepted() { |
||||
return txnAccepted; |
||||
} |
||||
|
||||
boolean hasAccepted(LogIndex id) { |
||||
return equals(txnAccepted, id); |
||||
} |
||||
|
||||
private static boolean equals(@Nullable ObjectId a, LogIndex b) { |
||||
return a != null && b != null && AnyObjectId.equals(a, b); |
||||
} |
||||
|
||||
/** |
||||
* Schedule a proposal round with the replica. |
||||
* <p> |
||||
* Called with {@link KetchLeader#lock} held by caller. |
||||
* |
||||
* @param round |
||||
* current round being run by the leader. |
||||
*/ |
||||
void pushTxnAcceptedAsync(Round round) { |
||||
List<ReceiveCommand> cmds = new ArrayList<>(); |
||||
if (commitSpeed == BATCHED) { |
||||
LogIndex committedIndex = leader.getCommitted(); |
||||
if (equals(txnAccepted, committedIndex) |
||||
&& !equals(txnCommitted, committedIndex)) { |
||||
prepareTxnCommitted(cmds, committedIndex); |
||||
} |
||||
} |
||||
|
||||
// TODO(sop) Lagging replicas should build accept on the fly.
|
||||
if (round.stageCommands != null) { |
||||
for (ReceiveCommand cmd : round.stageCommands) { |
||||
// TODO(sop): Do not send certain object graphs to replica.
|
||||
cmds.add(copy(cmd)); |
||||
} |
||||
} |
||||
cmds.add(new ReceiveCommand( |
||||
round.acceptedOldIndex, round.acceptedNewIndex, |
||||
getSystem().getTxnAccepted())); |
||||
pushAsync(new ReplicaPushRequest(this, cmds)); |
||||
} |
||||
|
||||
private static ReceiveCommand copy(ReceiveCommand c) { |
||||
return new ReceiveCommand(c.getOldId(), c.getNewId(), c.getRefName()); |
||||
} |
||||
|
||||
boolean shouldPushUnbatchedCommit(LogIndex committed, boolean leaderIdle) { |
||||
return (leaderIdle || commitSpeed == FAST) && hasAccepted(committed); |
||||
} |
||||
|
||||
void pushCommitAsync(LogIndex committed) { |
||||
List<ReceiveCommand> cmds = new ArrayList<>(); |
||||
prepareTxnCommitted(cmds, committed); |
||||
pushAsync(new ReplicaPushRequest(this, cmds)); |
||||
} |
||||
|
||||
private void prepareTxnCommitted(List<ReceiveCommand> cmds, |
||||
ObjectId committed) { |
||||
removeStaged(cmds, committed); |
||||
cmds.add(new ReceiveCommand( |
||||
txnCommitted, committed, |
||||
getSystem().getTxnCommitted())); |
||||
} |
||||
|
||||
private void removeStaged(List<ReceiveCommand> cmds, ObjectId committed) { |
||||
List<ReceiveCommand> a = staged.remove(committed); |
||||
if (a != null) { |
||||
delete(cmds, a); |
||||
} |
||||
if (staged.isEmpty() || !(committed instanceof LogIndex)) { |
||||
return; |
||||
} |
||||
|
||||
LogIndex committedIndex = (LogIndex) committed; |
||||
Iterator<Map.Entry<ObjectId, List<ReceiveCommand>>> itr = staged |
||||
.entrySet().iterator(); |
||||
while (itr.hasNext()) { |
||||
Map.Entry<ObjectId, List<ReceiveCommand>> e = itr.next(); |
||||
if (e.getKey() instanceof LogIndex) { |
||||
LogIndex stagedIndex = (LogIndex) e.getKey(); |
||||
if (stagedIndex.isBefore(committedIndex)) { |
||||
delete(cmds, e.getValue()); |
||||
itr.remove(); |
||||
} |
||||
} |
||||
} |
||||
} |
||||
|
||||
private static void delete(List<ReceiveCommand> cmds, |
||||
List<ReceiveCommand> createCmds) { |
||||
for (ReceiveCommand cmd : createCmds) { |
||||
ObjectId id = cmd.getNewId(); |
||||
String name = cmd.getRefName(); |
||||
cmds.add(new ReceiveCommand(id, ObjectId.zeroId(), name)); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Determine the next push for this replica (if any) and start it. |
||||
* <p> |
||||
* If the replica has successfully accepted the committed state of the |
||||
* leader, this method will push all references to the replica using the |
||||
* configured {@link CommitMethod}. |
||||
* <p> |
||||
* If the replica is {@link State#LAGGING} this method will begin catch up |
||||
* by sending a more recent {@code refs/txn/accepted}. |
||||
* <p> |
||||
* Must be invoked with {@link KetchLeader#lock} held by caller. |
||||
*/ |
||||
private void runNextPushRequest() { |
||||
LogIndex committed = leader.getCommitted(); |
||||
if (!equals(txnCommitted, committed) |
||||
&& shouldPushUnbatchedCommit(committed, leader.isIdle())) { |
||||
pushCommitAsync(committed); |
||||
} |
||||
|
||||
if (queued.isEmpty() || !running.isEmpty() || waitingForRetry()) { |
||||
return; |
||||
} |
||||
|
||||
// Collapse all queued requests into a single request.
|
||||
Map<String, ReceiveCommand> cmdMap = new HashMap<>(); |
||||
for (ReplicaPushRequest req : queued) { |
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
String name = cmd.getRefName(); |
||||
ReceiveCommand old = cmdMap.remove(name); |
||||
if (old != null) { |
||||
cmd = new ReceiveCommand( |
||||
old.getOldId(), cmd.getNewId(), |
||||
name); |
||||
} |
||||
cmdMap.put(name, cmd); |
||||
} |
||||
} |
||||
queued.clear(); |
||||
waiting.clear(); |
||||
|
||||
List<ReceiveCommand> next = new ArrayList<>(cmdMap.values()); |
||||
for (ReceiveCommand cmd : next) { |
||||
running.put(cmd.getRefName(), cmd); |
||||
} |
||||
startPush(new ReplicaPushRequest(this, next)); |
||||
} |
||||
|
||||
private void pushAsync(ReplicaPushRequest req) { |
||||
if (defer(req)) { |
||||
// TODO(sop) Collapse during long retry outage.
|
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
waiting.put(cmd.getRefName(), cmd); |
||||
} |
||||
queued.add(req); |
||||
} else { |
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
running.put(cmd.getRefName(), cmd); |
||||
} |
||||
startPush(req); |
||||
} |
||||
} |
||||
|
||||
private boolean defer(ReplicaPushRequest req) { |
||||
if (waitingForRetry()) { |
||||
// Prior communication failure; everything is deferred.
|
||||
return true; |
||||
} |
||||
|
||||
for (ReceiveCommand nextCmd : req.getCommands()) { |
||||
ReceiveCommand priorCmd = waiting.get(nextCmd.getRefName()); |
||||
if (priorCmd == null) { |
||||
priorCmd = running.get(nextCmd.getRefName()); |
||||
} |
||||
if (priorCmd != null) { |
||||
// Another request pending on same ref; that must go first.
|
||||
// Verify priorCmd.newId == nextCmd.oldId?
|
||||
return true; |
||||
} |
||||
} |
||||
return false; |
||||
} |
||||
|
||||
private boolean waitingForRetry() { |
||||
Future<?> f = retryFuture; |
||||
return f != null && !f.isDone(); |
||||
} |
||||
|
||||
private void retryLater(ReplicaPushRequest req) { |
||||
Collection<ReceiveCommand> cmds = req.getCommands(); |
||||
for (ReceiveCommand cmd : cmds) { |
||||
cmd.setResult(NOT_ATTEMPTED, null); |
||||
if (!waiting.containsKey(cmd.getRefName())) { |
||||
waiting.put(cmd.getRefName(), cmd); |
||||
} |
||||
} |
||||
queued.add(0, new ReplicaPushRequest(this, cmds)); |
||||
|
||||
if (!waitingForRetry()) { |
||||
long delay = KetchSystem.delay( |
||||
lastRetryMillis, |
||||
minRetryMillis, maxRetryMillis); |
||||
if (log.isDebugEnabled()) { |
||||
log.debug("Retrying {} after {} ms", //$NON-NLS-1$
|
||||
describeForLog(), Long.valueOf(delay)); |
||||
} |
||||
lastRetryMillis = delay; |
||||
retryAtMillis = SystemReader.getInstance().getCurrentTime() + delay; |
||||
retryFuture = getSystem().getExecutor() |
||||
.schedule(new WeakRetryPush(this), delay, MILLISECONDS); |
||||
} |
||||
} |
||||
|
||||
/** Weakly holds a retrying replica, allowing it to garbage collect. */ |
||||
static class WeakRetryPush extends WeakReference<KetchReplica> |
||||
implements Callable<Void> { |
||||
WeakRetryPush(KetchReplica r) { |
||||
super(r); |
||||
} |
||||
|
||||
@Override |
||||
public Void call() throws Exception { |
||||
KetchReplica r = get(); |
||||
if (r != null) { |
||||
r.doRetryPush(); |
||||
} |
||||
return null; |
||||
} |
||||
} |
||||
|
||||
private void doRetryPush() { |
||||
leader.lock.lock(); |
||||
try { |
||||
retryFuture = null; |
||||
runNextPushRequest(); |
||||
} finally { |
||||
leader.lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Begin executing a single push. |
||||
* <p> |
||||
* This method must move processing onto another thread. |
||||
* Called with {@link KetchLeader#lock} held by caller. |
||||
* |
||||
* @param req |
||||
* the request to send to the replica. |
||||
*/ |
||||
protected abstract void startPush(ReplicaPushRequest req); |
||||
|
||||
/** |
||||
* Callback from {@link ReplicaPushRequest} upon success or failure. |
||||
* <p> |
||||
* Acquires the {@link KetchLeader#lock} and updates the leader's internal |
||||
* knowledge about this replica to reflect what has been learned during a |
||||
* push to the replica. In some cases of divergence this method may take |
||||
* some time to determine how the replica has diverged; to reduce contention |
||||
* this is evaluated before acquiring the leader lock. |
||||
* |
||||
* @param repo |
||||
* local repository instance used by the push thread. |
||||
* @param req |
||||
* push request just attempted. |
||||
*/ |
||||
void afterPush(@Nullable Repository repo, ReplicaPushRequest req) { |
||||
ReceiveCommand acceptCmd = null; |
||||
ReceiveCommand commitCmd = null; |
||||
List<ReceiveCommand> stages = null; |
||||
|
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
String name = cmd.getRefName(); |
||||
if (name.equals(getSystem().getTxnAccepted())) { |
||||
acceptCmd = cmd; |
||||
} else if (name.equals(getSystem().getTxnCommitted())) { |
||||
commitCmd = cmd; |
||||
} else if (cmd.getResult() == OK && cmd.getType() == CREATE |
||||
&& name.startsWith(getSystem().getTxnStage())) { |
||||
if (stages == null) { |
||||
stages = new ArrayList<>(); |
||||
} |
||||
stages.add(cmd); |
||||
} |
||||
} |
||||
|
||||
State newState = null; |
||||
ObjectId acceptId = readId(req, acceptCmd); |
||||
if (repo != null && acceptCmd != null && acceptCmd.getResult() != OK |
||||
&& req.getException() == null) { |
||||
try (LagCheck lag = new LagCheck(this, repo)) { |
||||
newState = lag.check(acceptId, acceptCmd); |
||||
acceptId = lag.getRemoteId(); |
||||
} |
||||
} |
||||
|
||||
leader.lock.lock(); |
||||
try { |
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
running.remove(cmd.getRefName()); |
||||
} |
||||
|
||||
Throwable err = req.getException(); |
||||
if (err != null) { |
||||
state = OFFLINE; |
||||
error = err.toString(); |
||||
retryLater(req); |
||||
leader.onReplicaUpdate(this); |
||||
return; |
||||
} |
||||
|
||||
lastRetryMillis = 0; |
||||
error = null; |
||||
updateView(req, acceptId, commitCmd); |
||||
|
||||
if (acceptCmd != null && acceptCmd.getResult() == OK) { |
||||
state = hasAccepted(leader.getHead()) ? CURRENT : LAGGING; |
||||
if (stages != null) { |
||||
staged.put(acceptCmd.getNewId(), stages); |
||||
} |
||||
} else if (newState != null) { |
||||
state = newState; |
||||
} |
||||
|
||||
leader.onReplicaUpdate(this); |
||||
runNextPushRequest(); |
||||
} finally { |
||||
leader.lock.unlock(); |
||||
} |
||||
} |
||||
|
||||
private void updateView(ReplicaPushRequest req, @Nullable ObjectId acceptId, |
||||
ReceiveCommand commitCmd) { |
||||
if (acceptId != null) { |
||||
txnAccepted = acceptId; |
||||
} |
||||
|
||||
ObjectId committed = readId(req, commitCmd); |
||||
if (committed != null) { |
||||
txnCommitted = committed; |
||||
} else if (acceptId != null && txnCommitted == null) { |
||||
// Initialize during first conversation.
|
||||
Map<String, Ref> adv = req.getRefs(); |
||||
if (adv != null) { |
||||
Ref refs = adv.get(getSystem().getTxnCommitted()); |
||||
txnCommitted = getId(refs); |
||||
} |
||||
} |
||||
} |
||||
|
||||
@Nullable |
||||
private static ObjectId readId(ReplicaPushRequest req, |
||||
@Nullable ReceiveCommand cmd) { |
||||
if (cmd == null) { |
||||
// Ref was not in the command list, do not trust advertisement.
|
||||
return null; |
||||
|
||||
} else if (cmd.getResult() == OK) { |
||||
// Currently at newId.
|
||||
return cmd.getNewId(); |
||||
} |
||||
|
||||
Map<String, Ref> refs = req.getRefs(); |
||||
return refs != null ? getId(refs.get(cmd.getRefName())) : null; |
||||
} |
||||
|
||||
/** |
||||
* Fetch objects from the remote using the calling thread. |
||||
* <p> |
||||
* Called without {@link KetchLeader#lock}. |
||||
* |
||||
* @param repo |
||||
* local repository to fetch objects into. |
||||
* @param req |
||||
* the request to fetch from a replica. |
||||
* @throws IOException |
||||
* communication with the replica was not possible. |
||||
*/ |
||||
protected abstract void blockingFetch(Repository repo, |
||||
ReplicaFetchRequest req) throws IOException; |
||||
|
||||
/** |
||||
* Build a list of commands to commit {@link CommitMethod#ALL_REFS}. |
||||
* |
||||
* @param git |
||||
* local leader repository to read committed state from. |
||||
* @param current |
||||
* all known references in the replica's repository. Typically |
||||
* this comes from a push advertisement. |
||||
* @param committed |
||||
* state being pushed to {@code refs/txn/committed}. |
||||
* @return commands to update during commit. |
||||
* @throws IOException |
||||
* cannot read the committed state. |
||||
*/ |
||||
protected Collection<ReceiveCommand> prepareCommit(Repository git, |
||||
Map<String, Ref> current, ObjectId committed) throws IOException { |
||||
List<ReceiveCommand> delta = new ArrayList<>(); |
||||
Map<String, Ref> remote = new HashMap<>(current); |
||||
try (RevWalk rw = new RevWalk(git); |
||||
TreeWalk tw = new TreeWalk(rw.getObjectReader())) { |
||||
tw.setRecursive(true); |
||||
tw.addTree(rw.parseCommit(committed).getTree()); |
||||
while (tw.next()) { |
||||
if (tw.getRawMode(0) != TYPE_GITLINK |
||||
|| tw.isPathSuffix(PEEL, 2)) { |
||||
// Symbolic references cannot be pushed.
|
||||
// Caching peeled values is handled remotely.
|
||||
continue; |
||||
} |
||||
|
||||
// TODO(sop) Do not send certain ref names to replica.
|
||||
String name = RefTree.refName(tw.getPathString()); |
||||
Ref oldRef = remote.remove(name); |
||||
ObjectId oldId = getId(oldRef); |
||||
ObjectId newId = tw.getObjectId(0); |
||||
if (!AnyObjectId.equals(oldId, newId)) { |
||||
delta.add(new ReceiveCommand(oldId, newId, name)); |
||||
} |
||||
} |
||||
} |
||||
|
||||
// Delete any extra references not in the committed state.
|
||||
for (Ref ref : remote.values()) { |
||||
if (canDelete(ref)) { |
||||
delta.add(new ReceiveCommand( |
||||
ref.getObjectId(), ObjectId.zeroId(), |
||||
ref.getName())); |
||||
} |
||||
} |
||||
return delta; |
||||
} |
||||
|
||||
boolean canDelete(Ref ref) { |
||||
String name = ref.getName(); |
||||
if (HEAD.equals(name)) { |
||||
return false; |
||||
} |
||||
if (name.startsWith(getSystem().getTxnNamespace())) { |
||||
return false; |
||||
} |
||||
// TODO(sop) Do not delete precious names from replica.
|
||||
return true; |
||||
} |
||||
|
||||
@NonNull |
||||
static ObjectId getId(@Nullable Ref ref) { |
||||
if (ref != null) { |
||||
ObjectId id = ref.getObjectId(); |
||||
if (id != null) { |
||||
return id; |
||||
} |
||||
} |
||||
return ObjectId.zeroId(); |
||||
} |
||||
} |
||||
@ -0,0 +1,301 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.ACCEPTED; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.COMMITTED; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.CONFIG_KEY_TYPE; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.CONFIG_SECTION_KETCH; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.DEFAULT_TXN_NAMESPACE; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.STAGE; |
||||
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_NAME; |
||||
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_REMOTE; |
||||
|
||||
import java.net.URISyntaxException; |
||||
import java.util.ArrayList; |
||||
import java.util.List; |
||||
import java.util.Random; |
||||
import java.util.concurrent.Executors; |
||||
import java.util.concurrent.ScheduledExecutorService; |
||||
import java.util.concurrent.ThreadFactory; |
||||
import java.util.concurrent.atomic.AtomicInteger; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.Config; |
||||
import org.eclipse.jgit.lib.PersonIdent; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.transport.RemoteConfig; |
||||
import org.eclipse.jgit.transport.URIish; |
||||
import org.slf4j.Logger; |
||||
import org.slf4j.LoggerFactory; |
||||
|
||||
/** |
||||
* Ketch system-wide configuration. |
||||
* <p> |
||||
* This class provides useful defaults for testing and small proof of concepts. |
||||
* Full scale installations are expected to subclass and override methods to |
||||
* provide consistent configuration across all managed repositories. |
||||
* <p> |
||||
* Servers should configure their own {@link ScheduledExecutorService}. |
||||
*/ |
||||
public class KetchSystem { |
||||
private static final Random RNG = new Random(); |
||||
|
||||
/** @return default executor, one thread per available processor. */ |
||||
public static ScheduledExecutorService defaultExecutor() { |
||||
return DefaultExecutorHolder.I; |
||||
} |
||||
|
||||
private final ScheduledExecutorService executor; |
||||
private final String txnNamespace; |
||||
private final String txnAccepted; |
||||
private final String txnCommitted; |
||||
private final String txnStage; |
||||
|
||||
/** Create a default system with a thread pool of 1 thread per CPU. */ |
||||
public KetchSystem() { |
||||
this(defaultExecutor(), DEFAULT_TXN_NAMESPACE); |
||||
} |
||||
|
||||
/** |
||||
* Create a Ketch system with the provided executor service. |
||||
* |
||||
* @param executor |
||||
* thread pool to run background operations. |
||||
* @param txnNamespace |
||||
* reference namespace for the RefTree graph and associated |
||||
* transaction state. Must begin with {@code "refs/"} and end |
||||
* with {@code '/'}, for example {@code "refs/txn/"}. |
||||
*/ |
||||
public KetchSystem(ScheduledExecutorService executor, String txnNamespace) { |
||||
this.executor = executor; |
||||
this.txnNamespace = txnNamespace; |
||||
this.txnAccepted = txnNamespace + ACCEPTED; |
||||
this.txnCommitted = txnNamespace + COMMITTED; |
||||
this.txnStage = txnNamespace + STAGE; |
||||
} |
||||
|
||||
/** @return executor to perform background operations. */ |
||||
public ScheduledExecutorService getExecutor() { |
||||
return executor; |
||||
} |
||||
|
||||
/** |
||||
* Get the namespace used for the RefTree graph and transaction management. |
||||
* |
||||
* @return reference namespace such as {@code "refs/txn/"}. |
||||
*/ |
||||
public String getTxnNamespace() { |
||||
return txnNamespace; |
||||
} |
||||
|
||||
/** @return name of the accepted RefTree graph. */ |
||||
public String getTxnAccepted() { |
||||
return txnAccepted; |
||||
} |
||||
|
||||
/** @return name of the committed RefTree graph. */ |
||||
public String getTxnCommitted() { |
||||
return txnCommitted; |
||||
} |
||||
|
||||
/** @return prefix for staged objects, e.g. {@code "refs/txn/stage/"}. */ |
||||
public String getTxnStage() { |
||||
return txnStage; |
||||
} |
||||
|
||||
/** @return identity line for the committer header of a RefTreeGraph. */ |
||||
public PersonIdent newCommitter() { |
||||
String name = "ketch"; //$NON-NLS-1$
|
||||
String email = "ketch@system"; //$NON-NLS-1$
|
||||
return new PersonIdent(name, email); |
||||
} |
||||
|
||||
/** |
||||
* Construct a random tag to identify a candidate during leader election. |
||||
* <p> |
||||
* Multiple processes trying to elect themselves leaders at exactly the same |
||||
* time (rounded to seconds) using the same {@link #newCommitter()} identity |
||||
* strings, for the same term, may generate the same ObjectId for the |
||||
* election commit and falsely assume they have both won. |
||||
* <p> |
||||
* Candidates add this tag to their election ballot commit to disambiguate |
||||
* the election. The tag only needs to be unique for a given triplet of |
||||
* {@link #newCommitter()}, system time (rounded to seconds), and term. If |
||||
* every replica in the system uses a unique {@code newCommitter} (such as |
||||
* including the host name after the {@code "@"} in the email address) the |
||||
* tag could be the empty string. |
||||
* <p> |
||||
* The default implementation generates a few bytes of random data. |
||||
* |
||||
* @return unique tag; null or empty string if {@code newCommitter()} is |
||||
* sufficiently unique to identify the leader. |
||||
*/ |
||||
@Nullable |
||||
public String newLeaderTag() { |
||||
int n = RNG.nextInt(1 << (6 * 4)); |
||||
return String.format("%06x", Integer.valueOf(n)); //$NON-NLS-1$
|
||||
} |
||||
|
||||
/** |
||||
* Construct the KetchLeader instance of a repository. |
||||
* |
||||
* @param repo |
||||
* local repository stored by the leader. |
||||
* @return leader instance. |
||||
* @throws URISyntaxException |
||||
* a follower configuration contains an unsupported URI. |
||||
*/ |
||||
public KetchLeader createLeader(final Repository repo) |
||||
throws URISyntaxException { |
||||
KetchLeader leader = new KetchLeader(this) { |
||||
@Override |
||||
protected Repository openRepository() { |
||||
repo.incrementOpen(); |
||||
return repo; |
||||
} |
||||
}; |
||||
leader.setReplicas(createReplicas(leader, repo)); |
||||
return leader; |
||||
} |
||||
|
||||
/** |
||||
* Get the collection of replicas for a repository. |
||||
* <p> |
||||
* The collection of replicas must include the local repository. |
||||
* |
||||
* @param leader |
||||
* the leader driving these replicas. |
||||
* @param repo |
||||
* repository to get the replicas of. |
||||
* @return collection of replicas for the specified repository. |
||||
* @throws URISyntaxException |
||||
* a configured URI is invalid. |
||||
*/ |
||||
protected List<KetchReplica> createReplicas(KetchLeader leader, |
||||
Repository repo) throws URISyntaxException { |
||||
List<KetchReplica> replicas = new ArrayList<>(); |
||||
Config cfg = repo.getConfig(); |
||||
String localName = getLocalName(cfg); |
||||
for (String name : cfg.getSubsections(CONFIG_KEY_REMOTE)) { |
||||
if (!hasParticipation(cfg, name)) { |
||||
continue; |
||||
} |
||||
|
||||
ReplicaConfig kc = ReplicaConfig.newFromConfig(cfg, name); |
||||
if (name.equals(localName)) { |
||||
replicas.add(new LocalReplica(leader, name, kc)); |
||||
continue; |
||||
} |
||||
|
||||
RemoteConfig rc = new RemoteConfig(cfg, name); |
||||
List<URIish> uris = rc.getPushURIs(); |
||||
if (uris.isEmpty()) { |
||||
uris = rc.getURIs(); |
||||
} |
||||
for (URIish uri : uris) { |
||||
String n = uris.size() == 1 ? name : uri.getHost(); |
||||
replicas.add(new RemoteGitReplica(leader, n, uri, kc, rc)); |
||||
} |
||||
} |
||||
return replicas; |
||||
} |
||||
|
||||
private static boolean hasParticipation(Config cfg, String name) { |
||||
return cfg.getString(CONFIG_KEY_REMOTE, name, CONFIG_KEY_TYPE) != null; |
||||
} |
||||
|
||||
private static String getLocalName(Config cfg) { |
||||
return cfg.getString(CONFIG_SECTION_KETCH, null, CONFIG_KEY_NAME); |
||||
} |
||||
|
||||
static class DefaultExecutorHolder { |
||||
private static final Logger log = LoggerFactory.getLogger(KetchSystem.class); |
||||
static final ScheduledExecutorService I = create(); |
||||
|
||||
private static ScheduledExecutorService create() { |
||||
int cores = Runtime.getRuntime().availableProcessors(); |
||||
int threads = Math.max(5, cores); |
||||
log.info("Using {} threads", Integer.valueOf(threads)); //$NON-NLS-1$
|
||||
return Executors.newScheduledThreadPool( |
||||
threads, |
||||
new ThreadFactory() { |
||||
private final AtomicInteger threadCnt = new AtomicInteger(); |
||||
|
||||
@Override |
||||
public Thread newThread(Runnable r) { |
||||
int id = threadCnt.incrementAndGet(); |
||||
Thread thr = new Thread(r); |
||||
thr.setName("KetchExecutor-" + id); //$NON-NLS-1$
|
||||
return thr; |
||||
} |
||||
}); |
||||
} |
||||
|
||||
private DefaultExecutorHolder() { |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Compute a delay in a {@code min..max} interval with random jitter. |
||||
* |
||||
* @param last |
||||
* amount of delay waited before the last attempt. This is used |
||||
* to seed the next delay interval. Should be 0 if there was no |
||||
* prior delay. |
||||
* @param min |
||||
* shortest amount of allowable delay between attempts. |
||||
* @param max |
||||
* longest amount of allowable delay between attempts. |
||||
* @return new amount of delay to wait before the next attempt. |
||||
*/ |
||||
static long delay(long last, long min, long max) { |
||||
long r = Math.max(0, last * 3 - min); |
||||
if (r > 0) { |
||||
int c = (int) Math.min(r + 1, Integer.MAX_VALUE); |
||||
r = RNG.nextInt(c); |
||||
} |
||||
return Math.max(Math.min(min + r, max), min); |
||||
} |
||||
} |
||||
@ -0,0 +1,70 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import org.eclipse.jgit.nls.NLS; |
||||
import org.eclipse.jgit.nls.TranslationBundle; |
||||
|
||||
/** Translation bundle for the Ketch implementation. */ |
||||
public class KetchText extends TranslationBundle { |
||||
/** @return instance of this translation bundle. */ |
||||
public static KetchText get() { |
||||
return NLS.getBundleFor(KetchText.class); |
||||
} |
||||
|
||||
// @formatter:off
|
||||
/***/ public String accepted; |
||||
/***/ public String cannotFetchFromLocalReplica; |
||||
/***/ public String failed; |
||||
/***/ public String invalidFollowerUri; |
||||
/***/ public String leaderFailedToStore; |
||||
/***/ public String localReplicaRequired; |
||||
/***/ public String mismatchedTxnNamespace; |
||||
/***/ public String outsideTxnNamespace; |
||||
/***/ public String proposingUpdates; |
||||
/***/ public String queuedProposalFailedToApply; |
||||
/***/ public String starting; |
||||
/***/ public String unsupportedVoterCount; |
||||
/***/ public String waitingForQueue; |
||||
} |
||||
@ -0,0 +1,183 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.AHEAD; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.DIVERGENT; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.LAGGING; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.UNKNOWN; |
||||
import static org.eclipse.jgit.lib.Constants.OBJ_COMMIT; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.Collections; |
||||
import java.util.Map; |
||||
|
||||
import org.eclipse.jgit.errors.MissingObjectException; |
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.revwalk.RevCommit; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** |
||||
* A helper to check if a {@link KetchReplica} is ahead or behind the leader. |
||||
*/ |
||||
class LagCheck implements AutoCloseable { |
||||
private final KetchReplica replica; |
||||
private final Repository repo; |
||||
private RevWalk rw; |
||||
private ObjectId remoteId; |
||||
|
||||
LagCheck(KetchReplica replica, Repository repo) { |
||||
this.replica = replica; |
||||
this.repo = repo; |
||||
initRevWalk(); |
||||
} |
||||
|
||||
private void initRevWalk() { |
||||
if (rw != null) { |
||||
rw.close(); |
||||
} |
||||
|
||||
rw = new RevWalk(repo); |
||||
rw.setRetainBody(false); |
||||
} |
||||
|
||||
public void close() { |
||||
if (rw != null) { |
||||
rw.close(); |
||||
rw = null; |
||||
} |
||||
} |
||||
|
||||
ObjectId getRemoteId() { |
||||
return remoteId; |
||||
} |
||||
|
||||
KetchReplica.State check(ObjectId acceptId, ReceiveCommand acceptCmd) { |
||||
remoteId = acceptId; |
||||
if (remoteId == null) { |
||||
// Nothing advertised by the replica, value is unknown.
|
||||
return UNKNOWN; |
||||
} |
||||
|
||||
if (AnyObjectId.equals(remoteId, ObjectId.zeroId())) { |
||||
// Replica does not have the txnAccepted reference.
|
||||
return LAGGING; |
||||
} |
||||
|
||||
try { |
||||
RevCommit remote; |
||||
try { |
||||
remote = parseRemoteCommit(acceptCmd.getRefName()); |
||||
} catch (RefGoneException gone) { |
||||
// Replica does not have the txnAccepted reference.
|
||||
return LAGGING; |
||||
} catch (MissingObjectException notFound) { |
||||
// Local repository does not know this commit so it cannot
|
||||
// be including the replica's log.
|
||||
return DIVERGENT; |
||||
} |
||||
|
||||
RevCommit head = rw.parseCommit(acceptCmd.getNewId()); |
||||
if (rw.isMergedInto(remote, head)) { |
||||
return LAGGING; |
||||
} |
||||
|
||||
// TODO(sop) Check term to see if my leader was deposed.
|
||||
if (rw.isMergedInto(head, remote)) { |
||||
return AHEAD; |
||||
} else { |
||||
return DIVERGENT; |
||||
} |
||||
} catch (IOException err) { |
||||
KetchReplica.log.error(String.format( |
||||
"Cannot compare %s", //$NON-NLS-1$
|
||||
acceptCmd.getRefName()), err); |
||||
return UNKNOWN; |
||||
} |
||||
} |
||||
|
||||
private RevCommit parseRemoteCommit(String refName) |
||||
throws IOException, MissingObjectException, RefGoneException { |
||||
try { |
||||
return rw.parseCommit(remoteId); |
||||
} catch (MissingObjectException notLocal) { |
||||
// Fall through and try to acquire the object by fetching it.
|
||||
} |
||||
|
||||
ReplicaFetchRequest fetch = new ReplicaFetchRequest( |
||||
Collections.singleton(refName), |
||||
Collections.<ObjectId> emptySet()); |
||||
try { |
||||
replica.blockingFetch(repo, fetch); |
||||
} catch (IOException fetchErr) { |
||||
KetchReplica.log.error(String.format( |
||||
"Cannot fetch %s (%s) from %s", //$NON-NLS-1$
|
||||
remoteId.abbreviate(8).name(), refName, |
||||
replica.describeForLog()), fetchErr); |
||||
throw new MissingObjectException(remoteId, OBJ_COMMIT); |
||||
} |
||||
|
||||
Map<String, Ref> adv = fetch.getRefs(); |
||||
if (adv == null) { |
||||
throw new MissingObjectException(remoteId, OBJ_COMMIT); |
||||
} |
||||
|
||||
Ref ref = adv.get(refName); |
||||
if (ref == null || ref.getObjectId() == null) { |
||||
throw new RefGoneException(); |
||||
} |
||||
|
||||
initRevWalk(); |
||||
remoteId = ref.getObjectId(); |
||||
return rw.parseCommit(remoteId); |
||||
} |
||||
|
||||
private static class RefGoneException extends Exception { |
||||
private static final long serialVersionUID = 1L; |
||||
} |
||||
} |
||||
@ -0,0 +1,164 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.State.OFFLINE; |
||||
|
||||
import java.util.ArrayList; |
||||
import java.util.Collection; |
||||
import java.util.Collections; |
||||
import java.util.List; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
|
||||
/** A snapshot of a leader and its view of the world. */ |
||||
public class LeaderSnapshot { |
||||
final List<ReplicaSnapshot> replicas = new ArrayList<>(); |
||||
KetchLeader.State state; |
||||
long term; |
||||
LogIndex headIndex; |
||||
LogIndex committedIndex; |
||||
boolean idle; |
||||
|
||||
LeaderSnapshot() { |
||||
} |
||||
|
||||
/** @return unmodifiable view of configured replicas. */ |
||||
public Collection<ReplicaSnapshot> getReplicas() { |
||||
return Collections.unmodifiableList(replicas); |
||||
} |
||||
|
||||
/** @return current state of the leader. */ |
||||
public KetchLeader.State getState() { |
||||
return state; |
||||
} |
||||
|
||||
/** |
||||
* @return {@code true} if the leader is not running a round to reach |
||||
* consensus, and has no rounds queued. |
||||
*/ |
||||
public boolean isIdle() { |
||||
return idle; |
||||
} |
||||
|
||||
/** |
||||
* @return term of this leader. Valid only if {@link #getState()} is |
||||
* currently {@link KetchLeader.State#LEADER}. |
||||
*/ |
||||
public long getTerm() { |
||||
return term; |
||||
} |
||||
|
||||
/** |
||||
* @return end of the leader's log; null if leader hasn't started up enough |
||||
* to begin its own election. |
||||
*/ |
||||
@Nullable |
||||
public LogIndex getHead() { |
||||
return headIndex; |
||||
} |
||||
|
||||
/** |
||||
* @return state the leader knows is committed on a majority of participant |
||||
* replicas. Null until the leader instance has committed a log |
||||
* index within its own term. |
||||
*/ |
||||
@Nullable |
||||
public LogIndex getCommitted() { |
||||
return committedIndex; |
||||
} |
||||
|
||||
@Override |
||||
public String toString() { |
||||
StringBuilder s = new StringBuilder(); |
||||
s.append(isIdle() ? "IDLE" : "RUNNING"); //$NON-NLS-1$ //$NON-NLS-2$
|
||||
s.append(" state ").append(getState()); //$NON-NLS-1$
|
||||
if (getTerm() > 0) { |
||||
s.append(" term ").append(getTerm()); //$NON-NLS-1$
|
||||
} |
||||
s.append('\n'); |
||||
s.append(String.format( |
||||
"%-10s %12s %12s\n", //$NON-NLS-1$
|
||||
"Replica", "Accepted", "Committed")); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
|
||||
s.append("------------------------------------\n"); //$NON-NLS-1$
|
||||
debug(s, "(leader)", getHead(), getCommitted()); //$NON-NLS-1$
|
||||
s.append('\n'); |
||||
for (ReplicaSnapshot r : getReplicas()) { |
||||
debug(s, r); |
||||
s.append('\n'); |
||||
} |
||||
s.append('\n'); |
||||
return s.toString(); |
||||
} |
||||
|
||||
private static void debug(StringBuilder b, ReplicaSnapshot s) { |
||||
KetchReplica replica = s.getReplica(); |
||||
debug(b, replica.getName(), s.getAccepted(), s.getCommitted()); |
||||
b.append(String.format(" %-8s %s", //$NON-NLS-1$
|
||||
replica.getParticipation(), s.getState())); |
||||
if (s.getState() == OFFLINE) { |
||||
String err = s.getErrorMessage(); |
||||
if (err != null) { |
||||
b.append(" (").append(err).append(')'); //$NON-NLS-1$
|
||||
} |
||||
} |
||||
} |
||||
|
||||
private static void debug(StringBuilder s, String name, |
||||
ObjectId accepted, ObjectId committed) { |
||||
s.append(String.format( |
||||
"%-10s %-12s %-12s", //$NON-NLS-1$
|
||||
name, str(accepted), str(committed))); |
||||
} |
||||
|
||||
static String str(ObjectId c) { |
||||
if (c instanceof LogIndex) { |
||||
return ((LogIndex) c).describeForLog(); |
||||
} else if (c != null) { |
||||
return c.abbreviate(8).name(); |
||||
} |
||||
return "-"; //$NON-NLS-1$
|
||||
} |
||||
} |
||||
@ -0,0 +1,229 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.CommitMethod.ALL_REFS; |
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.CommitMethod.TXN_COMMITTED; |
||||
import static org.eclipse.jgit.lib.RefDatabase.ALL; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.OK; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.REJECTED_OTHER_REASON; |
||||
|
||||
import java.io.IOException; |
||||
import java.text.MessageFormat; |
||||
import java.util.ArrayList; |
||||
import java.util.Collection; |
||||
import java.util.List; |
||||
import java.util.Map; |
||||
|
||||
import org.eclipse.jgit.internal.storage.reftree.RefTreeDatabase; |
||||
import org.eclipse.jgit.lib.BatchRefUpdate; |
||||
import org.eclipse.jgit.lib.NullProgressMonitor; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.RefDatabase; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** Ketch replica running on the same system as the {@link KetchLeader}. */ |
||||
public class LocalReplica extends KetchReplica { |
||||
/** |
||||
* Configure a local replica. |
||||
* |
||||
* @param leader |
||||
* instance this replica follows. |
||||
* @param name |
||||
* unique-ish name identifying this replica for debugging. |
||||
* @param cfg |
||||
* how Ketch should treat the local system. |
||||
*/ |
||||
public LocalReplica(KetchLeader leader, String name, ReplicaConfig cfg) { |
||||
super(leader, name, cfg); |
||||
} |
||||
|
||||
@Override |
||||
protected String describeForLog() { |
||||
return String.format("%s (leader)", getName()); //$NON-NLS-1$
|
||||
} |
||||
|
||||
/** |
||||
* Initializes local replica by reading accepted and committed references. |
||||
* <p> |
||||
* Loads accepted and committed references from the reference database of |
||||
* the local replica and stores their current ObjectIds in memory. |
||||
* |
||||
* @param repo |
||||
* repository to initialize state from. |
||||
* @throws IOException |
||||
* cannot read repository state. |
||||
*/ |
||||
void initialize(Repository repo) throws IOException { |
||||
RefDatabase refdb = repo.getRefDatabase(); |
||||
if (refdb instanceof RefTreeDatabase) { |
||||
RefTreeDatabase treeDb = (RefTreeDatabase) refdb; |
||||
String txnNamespace = getSystem().getTxnNamespace(); |
||||
if (!txnNamespace.equals(treeDb.getTxnNamespace())) { |
||||
throw new IOException(MessageFormat.format( |
||||
KetchText.get().mismatchedTxnNamespace, |
||||
txnNamespace, treeDb.getTxnNamespace())); |
||||
} |
||||
refdb = treeDb.getBootstrap(); |
||||
} |
||||
initialize(refdb.exactRef( |
||||
getSystem().getTxnAccepted(), |
||||
getSystem().getTxnCommitted())); |
||||
} |
||||
|
||||
@Override |
||||
protected void startPush(final ReplicaPushRequest req) { |
||||
getSystem().getExecutor().execute(new Runnable() { |
||||
@Override |
||||
public void run() { |
||||
try (Repository git = getLeader().openRepository()) { |
||||
try { |
||||
update(git, req); |
||||
req.done(git); |
||||
} catch (Throwable err) { |
||||
req.setException(git, err); |
||||
} |
||||
} catch (IOException err) { |
||||
req.setException(null, err); |
||||
} |
||||
} |
||||
}); |
||||
} |
||||
|
||||
@Override |
||||
protected void blockingFetch(Repository repo, ReplicaFetchRequest req) |
||||
throws IOException { |
||||
throw new IOException(KetchText.get().cannotFetchFromLocalReplica); |
||||
} |
||||
|
||||
private void update(Repository git, ReplicaPushRequest req) |
||||
throws IOException { |
||||
RefDatabase refdb = git.getRefDatabase(); |
||||
CommitMethod method = getCommitMethod(); |
||||
|
||||
// Local replica probably uses RefTreeDatabase, the request should
|
||||
// be only for the txnNamespace, so drop to the bootstrap layer.
|
||||
if (refdb instanceof RefTreeDatabase) { |
||||
if (!isOnlyTxnNamespace(req.getCommands())) { |
||||
return; |
||||
} |
||||
|
||||
refdb = ((RefTreeDatabase) refdb).getBootstrap(); |
||||
method = TXN_COMMITTED; |
||||
} |
||||
|
||||
BatchRefUpdate batch = refdb.newBatchUpdate(); |
||||
batch.setRefLogIdent(getSystem().newCommitter()); |
||||
batch.setRefLogMessage("ketch", false); //$NON-NLS-1$
|
||||
batch.setAllowNonFastForwards(true); |
||||
|
||||
// RefDirectory updates multiple references sequentially.
|
||||
// Run everything else first, then accepted (if present),
|
||||
// then committed (if present). This ensures an earlier
|
||||
// failure will not update these critical references.
|
||||
ReceiveCommand accepted = null; |
||||
ReceiveCommand committed = null; |
||||
for (ReceiveCommand cmd : req.getCommands()) { |
||||
String name = cmd.getRefName(); |
||||
if (name.equals(getSystem().getTxnAccepted())) { |
||||
accepted = cmd; |
||||
} else if (name.equals(getSystem().getTxnCommitted())) { |
||||
committed = cmd; |
||||
} else { |
||||
batch.addCommand(cmd); |
||||
} |
||||
} |
||||
if (committed != null && method == ALL_REFS) { |
||||
Map<String, Ref> refs = refdb.getRefs(ALL); |
||||
batch.addCommand(prepareCommit(git, refs, committed.getNewId())); |
||||
} |
||||
if (accepted != null) { |
||||
batch.addCommand(accepted); |
||||
} |
||||
if (committed != null) { |
||||
batch.addCommand(committed); |
||||
} |
||||
|
||||
try (RevWalk rw = new RevWalk(git)) { |
||||
batch.execute(rw, NullProgressMonitor.INSTANCE); |
||||
} |
||||
|
||||
// KetchReplica only cares about accepted and committed in
|
||||
// advertisement. If they failed, store the current values
|
||||
// back in the ReplicaPushRequest.
|
||||
List<String> failed = new ArrayList<>(2); |
||||
checkFailed(failed, accepted); |
||||
checkFailed(failed, committed); |
||||
if (!failed.isEmpty()) { |
||||
String[] arr = failed.toArray(new String[failed.size()]); |
||||
req.setRefs(refdb.exactRef(arr)); |
||||
} |
||||
} |
||||
|
||||
private static void checkFailed(List<String> failed, ReceiveCommand cmd) { |
||||
if (cmd != null && cmd.getResult() != OK) { |
||||
failed.add(cmd.getRefName()); |
||||
} |
||||
} |
||||
|
||||
private boolean isOnlyTxnNamespace(Collection<ReceiveCommand> cmdList) { |
||||
// Be paranoid and reject non txnNamespace names, this
|
||||
// is a programming error in Ketch that should not occur.
|
||||
|
||||
String txnNamespace = getSystem().getTxnNamespace(); |
||||
for (ReceiveCommand cmd : cmdList) { |
||||
if (!cmd.getRefName().startsWith(txnNamespace)) { |
||||
cmd.setResult(REJECTED_OTHER_REASON, |
||||
MessageFormat.format( |
||||
KetchText.get().outsideTxnNamespace, |
||||
cmd.getRefName(), txnNamespace)); |
||||
ReceiveCommand.abort(cmdList); |
||||
return false; |
||||
} |
||||
} |
||||
return true; |
||||
} |
||||
} |
||||
@ -0,0 +1,119 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
|
||||
/** |
||||
* An ObjectId for a commit extended with incrementing log index. |
||||
* <p> |
||||
* For any two LogIndex instances, {@code A} is an ancestor of {@code C} |
||||
* reachable through parent edges in the graph if {@code A.index < C.index}. |
||||
* LogIndex provides a performance optimization for Ketch, the same information |
||||
* can be obtained from {@link org.eclipse.jgit.revwalk.RevWalk}. |
||||
* <p> |
||||
* Index values are only valid within a single {@link KetchLeader} instance |
||||
* after it has won an election. By restricting scope to a single leader new |
||||
* leaders do not need to traverse the entire history to determine the next |
||||
* {@code index} for new proposals. This differs from Raft, where leader |
||||
* election uses the log index and the term number to determine which replica |
||||
* holds a sufficiently up-to-date log. Since Ketch uses Git objects for storage |
||||
* of its replicated log, it keeps the term number as Raft does but uses |
||||
* standard Git operations to imply the log index. |
||||
* <p> |
||||
* {@link Round#runAsync(AnyObjectId)} bumps the index as each new round is |
||||
* constructed. |
||||
*/ |
||||
public class LogIndex extends ObjectId { |
||||
static LogIndex unknown(AnyObjectId id) { |
||||
return new LogIndex(id, 0); |
||||
} |
||||
|
||||
private final long index; |
||||
|
||||
private LogIndex(AnyObjectId id, long index) { |
||||
super(id); |
||||
this.index = index; |
||||
} |
||||
|
||||
LogIndex nextIndex(AnyObjectId id) { |
||||
return new LogIndex(id, index + 1); |
||||
} |
||||
|
||||
/** @return index provided by the current leader instance. */ |
||||
public long getIndex() { |
||||
return index; |
||||
} |
||||
|
||||
/** |
||||
* Check if this log position committed before another log position. |
||||
* <p> |
||||
* Only valid for log positions in memory for the current leader. |
||||
* |
||||
* @param c |
||||
* other (more recent) log position. |
||||
* @return true if this log position was before {@code c} or equal to c and |
||||
* therefore any agreement of {@code c} implies agreement on this |
||||
* log position. |
||||
*/ |
||||
boolean isBefore(LogIndex c) { |
||||
return index <= c.index; |
||||
} |
||||
|
||||
/** |
||||
* @return string suitable for debug logging containing the log index and |
||||
* abbreviated ObjectId. |
||||
*/ |
||||
@SuppressWarnings("boxing") |
||||
public String describeForLog() { |
||||
return String.format("%5d/%s", index, abbreviate(6).name()); //$NON-NLS-1$
|
||||
} |
||||
|
||||
@SuppressWarnings("boxing") |
||||
@Override |
||||
public String toString() { |
||||
return String.format("LogId[%5d/%s]", index, name()); //$NON-NLS-1$
|
||||
} |
||||
} |
||||
@ -0,0 +1,391 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.ABORTED; |
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.EXECUTED; |
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.NEW; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.NOT_ATTEMPTED; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.OK; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.ArrayList; |
||||
import java.util.Collection; |
||||
import java.util.Collections; |
||||
import java.util.List; |
||||
import java.util.concurrent.CopyOnWriteArrayList; |
||||
import java.util.concurrent.TimeUnit; |
||||
import java.util.concurrent.atomic.AtomicReference; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.errors.MissingObjectException; |
||||
import org.eclipse.jgit.internal.storage.reftree.Command; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.PersonIdent; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.PushCertificate; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** |
||||
* A proposal to be applied in a Ketch system. |
||||
* <p> |
||||
* Pushing to a Ketch leader results in the leader making a proposal. The |
||||
* proposal includes the list of reference updates. The leader attempts to send |
||||
* the proposal to a quorum of replicas by pushing the proposal to a "staging" |
||||
* area under the {@code refs/txn/stage/} namespace. If the proposal succeeds |
||||
* then the changes are durable and the leader can commit the proposal. |
||||
* <p> |
||||
* Proposals are executed by {@link KetchLeader#queueProposal(Proposal)}, which |
||||
* runs them asynchronously in the background. Proposals are thread-safe futures |
||||
* allowing callers to {@link #await()} for results or be notified by callback |
||||
* using {@link #addListener(Runnable)}. |
||||
*/ |
||||
public class Proposal { |
||||
/** Current state of the proposal. */ |
||||
public enum State { |
||||
/** Proposal has not yet been given to a {@link KetchLeader}. */ |
||||
NEW(false), |
||||
|
||||
/** |
||||
* Proposal was validated and has entered the queue, but a round |
||||
* containing this proposal has not started yet. |
||||
*/ |
||||
QUEUED(false), |
||||
|
||||
/** Round containing the proposal has begun and is in progress. */ |
||||
RUNNING(false), |
||||
|
||||
/** |
||||
* Proposal was executed through a round. Individual results from |
||||
* {@link Proposal#getCommands()}, {@link Command#getResult()} explain |
||||
* the success or failure outcome. |
||||
*/ |
||||
EXECUTED(true), |
||||
|
||||
/** Proposal was aborted and did not reach consensus. */ |
||||
ABORTED(true); |
||||
|
||||
private final boolean done; |
||||
|
||||
private State(boolean done) { |
||||
this.done = done; |
||||
} |
||||
|
||||
/** @return true if this is a terminal state. */ |
||||
public boolean isDone() { |
||||
return done; |
||||
} |
||||
} |
||||
|
||||
private final List<Command> commands; |
||||
private PersonIdent author; |
||||
private String message; |
||||
private PushCertificate pushCert; |
||||
private final List<Runnable> listeners = new CopyOnWriteArrayList<>(); |
||||
private final AtomicReference<State> state = new AtomicReference<>(NEW); |
||||
|
||||
/** |
||||
* Create a proposal from a list of Ketch commands. |
||||
* |
||||
* @param cmds |
||||
* prepared list of commands. |
||||
*/ |
||||
public Proposal(List<Command> cmds) { |
||||
commands = Collections.unmodifiableList(new ArrayList<>(cmds)); |
||||
} |
||||
|
||||
/** |
||||
* Create a proposal from a collection of received commands. |
||||
* |
||||
* @param rw |
||||
* walker to assist in preparing commands. |
||||
* @param cmds |
||||
* list of pending commands. |
||||
* @throws MissingObjectException |
||||
* newId of a command is not found locally. |
||||
* @throws IOException |
||||
* local objects cannot be accessed. |
||||
*/ |
||||
public Proposal(RevWalk rw, Collection<ReceiveCommand> cmds) |
||||
throws MissingObjectException, IOException { |
||||
commands = asCommandList(rw, cmds); |
||||
} |
||||
|
||||
private static List<Command> asCommandList(RevWalk rw, |
||||
Collection<ReceiveCommand> cmds) |
||||
throws MissingObjectException, IOException { |
||||
List<Command> commands = new ArrayList<>(cmds.size()); |
||||
for (ReceiveCommand cmd : cmds) { |
||||
commands.add(new Command(rw, cmd)); |
||||
} |
||||
return Collections.unmodifiableList(commands); |
||||
} |
||||
|
||||
/** @return commands from this proposal. */ |
||||
public Collection<Command> getCommands() { |
||||
return commands; |
||||
} |
||||
|
||||
/** @return optional author of the proposal. */ |
||||
@Nullable |
||||
public PersonIdent getAuthor() { |
||||
return author; |
||||
} |
||||
|
||||
/** |
||||
* Set the author for the proposal. |
||||
* |
||||
* @param who |
||||
* optional identity of the author of the proposal. |
||||
* @return {@code this} |
||||
*/ |
||||
public Proposal setAuthor(@Nullable PersonIdent who) { |
||||
author = who; |
||||
return this; |
||||
} |
||||
|
||||
/** @return optional message for the commit log of the RefTree. */ |
||||
@Nullable |
||||
public String getMessage() { |
||||
return message; |
||||
} |
||||
|
||||
/** |
||||
* Set the message to appear in the commit log of the RefTree. |
||||
* |
||||
* @param msg |
||||
* message text for the commit. |
||||
* @return {@code this} |
||||
*/ |
||||
public Proposal setMessage(@Nullable String msg) { |
||||
message = msg != null && !msg.isEmpty() ? msg : null; |
||||
return this; |
||||
} |
||||
|
||||
/** @return optional certificate signing the references. */ |
||||
@Nullable |
||||
public PushCertificate getPushCertificate() { |
||||
return pushCert; |
||||
} |
||||
|
||||
/** |
||||
* Set the push certificate signing the references. |
||||
* |
||||
* @param cert |
||||
* certificate, may be null. |
||||
* @return {@code this} |
||||
*/ |
||||
public Proposal setPushCertificate(@Nullable PushCertificate cert) { |
||||
pushCert = cert; |
||||
return this; |
||||
} |
||||
|
||||
/** |
||||
* Add a callback to be invoked when the proposal is done. |
||||
* <p> |
||||
* A proposal is done when it has entered either {@link State#EXECUTED} or |
||||
* {@link State#ABORTED} state. If the proposal is already done |
||||
* {@code callback.run()} is immediately invoked on the caller's thread. |
||||
* |
||||
* @param callback |
||||
* method to run after the proposal is done. The callback may be |
||||
* run on a Ketch system thread and should be completed quickly. |
||||
*/ |
||||
public void addListener(Runnable callback) { |
||||
boolean runNow = false; |
||||
synchronized (state) { |
||||
if (state.get().isDone()) { |
||||
runNow = true; |
||||
} else { |
||||
listeners.add(callback); |
||||
} |
||||
} |
||||
if (runNow) { |
||||
callback.run(); |
||||
} |
||||
} |
||||
|
||||
/** Set command result as OK. */ |
||||
void success() { |
||||
for (Command c : commands) { |
||||
if (c.getResult() == NOT_ATTEMPTED) { |
||||
c.setResult(OK); |
||||
} |
||||
} |
||||
notifyState(EXECUTED); |
||||
} |
||||
|
||||
/** Mark commands as "transaction aborted". */ |
||||
void abort() { |
||||
Command.abort(commands, null); |
||||
notifyState(ABORTED); |
||||
} |
||||
|
||||
/** @return read the current state of the proposal. */ |
||||
public State getState() { |
||||
return state.get(); |
||||
} |
||||
|
||||
/** |
||||
* @return {@code true} if the proposal was attempted. A true value does not |
||||
* mean consensus was reached, only that the proposal was considered |
||||
* and will not be making any more progress beyond its current |
||||
* state. |
||||
*/ |
||||
public boolean isDone() { |
||||
return state.get().isDone(); |
||||
} |
||||
|
||||
/** |
||||
* Wait for the proposal to be attempted and {@link #isDone()} to be true. |
||||
* |
||||
* @throws InterruptedException |
||||
* caller was interrupted before proposal executed. |
||||
*/ |
||||
public void await() throws InterruptedException { |
||||
synchronized (state) { |
||||
while (!state.get().isDone()) { |
||||
state.wait(); |
||||
} |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Wait for the proposal to be attempted and {@link #isDone()} to be true. |
||||
* |
||||
* @param wait |
||||
* how long to wait. |
||||
* @param unit |
||||
* unit describing the wait time. |
||||
* @return true if the proposal is done; false if the method timed out. |
||||
* @throws InterruptedException |
||||
* caller was interrupted before proposal executed. |
||||
*/ |
||||
public boolean await(long wait, TimeUnit unit) throws InterruptedException { |
||||
synchronized (state) { |
||||
if (state.get().isDone()) { |
||||
return true; |
||||
} |
||||
state.wait(unit.toMillis(wait)); |
||||
return state.get().isDone(); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Wait for the proposal to exit a state. |
||||
* |
||||
* @param notIn |
||||
* state the proposal should not be in to return. |
||||
* @param wait |
||||
* how long to wait. |
||||
* @param unit |
||||
* unit describing the wait time. |
||||
* @return true if the proposal exited the state; false on time out. |
||||
* @throws InterruptedException |
||||
* caller was interrupted before proposal executed. |
||||
*/ |
||||
public boolean awaitStateChange(State notIn, long wait, TimeUnit unit) |
||||
throws InterruptedException { |
||||
synchronized (state) { |
||||
if (state.get() != notIn) { |
||||
return true; |
||||
} |
||||
state.wait(unit.toMillis(wait)); |
||||
return state.get() != notIn; |
||||
} |
||||
} |
||||
|
||||
void notifyState(State s) { |
||||
synchronized (state) { |
||||
state.set(s); |
||||
state.notifyAll(); |
||||
} |
||||
if (s.isDone()) { |
||||
for (Runnable callback : listeners) { |
||||
callback.run(); |
||||
} |
||||
listeners.clear(); |
||||
} |
||||
} |
||||
|
||||
@Override |
||||
public String toString() { |
||||
StringBuilder s = new StringBuilder(); |
||||
s.append("Ketch Proposal {\n"); //$NON-NLS-1$
|
||||
s.append(" ").append(state.get()).append('\n'); //$NON-NLS-1$
|
||||
if (author != null) { |
||||
s.append(" author ").append(author).append('\n'); //$NON-NLS-1$
|
||||
} |
||||
if (message != null) { |
||||
s.append(" message ").append(message).append('\n'); //$NON-NLS-1$
|
||||
} |
||||
for (Command c : commands) { |
||||
s.append(" "); //$NON-NLS-1$
|
||||
format(s, c.getOldRef(), "CREATE"); //$NON-NLS-1$
|
||||
s.append(' '); |
||||
format(s, c.getNewRef(), "DELETE"); //$NON-NLS-1$
|
||||
s.append(' ').append(c.getRefName()); |
||||
if (c.getResult() != ReceiveCommand.Result.NOT_ATTEMPTED) { |
||||
s.append(' ').append(c.getResult()); // $NON-NLS-1$
|
||||
} |
||||
s.append('\n'); |
||||
} |
||||
s.append('}'); |
||||
return s.toString(); |
||||
} |
||||
|
||||
private static void format(StringBuilder s, @Nullable Ref r, String n) { |
||||
if (r == null) { |
||||
s.append(n); |
||||
} else if (r.isSymbolic()) { |
||||
s.append(r.getTarget().getName()); |
||||
} else { |
||||
ObjectId id = r.getObjectId(); |
||||
if (id != null) { |
||||
s.append(id.abbreviate(8).name()); |
||||
} |
||||
} |
||||
} |
||||
} |
||||
@ -0,0 +1,299 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.Proposal.State.RUNNING; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.Collections; |
||||
import java.util.HashMap; |
||||
import java.util.HashSet; |
||||
import java.util.List; |
||||
import java.util.Map; |
||||
import java.util.Set; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.internal.storage.reftree.Command; |
||||
import org.eclipse.jgit.internal.storage.reftree.RefTree; |
||||
import org.eclipse.jgit.lib.CommitBuilder; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.ObjectInserter; |
||||
import org.eclipse.jgit.lib.PersonIdent; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.revwalk.RevCommit; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** A {@link Round} that aggregates and sends user {@link Proposal}s. */ |
||||
class ProposalRound extends Round { |
||||
private final List<Proposal> todo; |
||||
private RefTree queuedTree; |
||||
|
||||
ProposalRound(KetchLeader leader, LogIndex head, List<Proposal> todo, |
||||
@Nullable RefTree tree) { |
||||
super(leader, head); |
||||
this.todo = todo; |
||||
|
||||
if (tree != null && canCombine(todo)) { |
||||
this.queuedTree = tree; |
||||
} else { |
||||
leader.roundHoldsReferenceToRefTree = false; |
||||
} |
||||
} |
||||
|
||||
private static boolean canCombine(List<Proposal> todo) { |
||||
Proposal first = todo.get(0); |
||||
for (int i = 1; i < todo.size(); i++) { |
||||
if (!canCombine(first, todo.get(i))) { |
||||
return false; |
||||
} |
||||
} |
||||
return true; |
||||
} |
||||
|
||||
private static boolean canCombine(Proposal a, Proposal b) { |
||||
String aMsg = nullToEmpty(a.getMessage()); |
||||
String bMsg = nullToEmpty(b.getMessage()); |
||||
return aMsg.equals(bMsg) && canCombine(a.getAuthor(), b.getAuthor()); |
||||
} |
||||
|
||||
private static String nullToEmpty(@Nullable String str) { |
||||
return str != null ? str : ""; //$NON-NLS-1$
|
||||
} |
||||
|
||||
private static boolean canCombine(@Nullable PersonIdent a, |
||||
@Nullable PersonIdent b) { |
||||
if (a != null && b != null) { |
||||
// Same name and email address. Combine timestamp as the two
|
||||
// proposals are running concurrently and appear together or
|
||||
// not at all from the point of view of an outside reader.
|
||||
return a.getName().equals(b.getName()) |
||||
&& a.getEmailAddress().equals(b.getEmailAddress()); |
||||
} |
||||
|
||||
// If a and b are null, both will be the system identity.
|
||||
return a == null && b == null; |
||||
} |
||||
|
||||
void start() throws IOException { |
||||
for (Proposal p : todo) { |
||||
p.notifyState(RUNNING); |
||||
} |
||||
try { |
||||
ObjectId id; |
||||
try (Repository git = leader.openRepository()) { |
||||
id = insertProposals(git); |
||||
} |
||||
runAsync(id); |
||||
} catch (NoOp e) { |
||||
for (Proposal p : todo) { |
||||
p.success(); |
||||
} |
||||
leader.lock.lock(); |
||||
try { |
||||
leader.nextRound(); |
||||
} finally { |
||||
leader.lock.unlock(); |
||||
} |
||||
} catch (IOException e) { |
||||
abort(); |
||||
throw e; |
||||
} |
||||
} |
||||
|
||||
private ObjectId insertProposals(Repository git) |
||||
throws IOException, NoOp { |
||||
ObjectId id; |
||||
try (ObjectInserter inserter = git.newObjectInserter()) { |
||||
// TODO(sop) Process signed push certificates.
|
||||
|
||||
if (queuedTree != null) { |
||||
id = insertSingleProposal(git, inserter); |
||||
} else { |
||||
id = insertMultiProposal(git, inserter); |
||||
} |
||||
|
||||
stageCommands = makeStageList(git, inserter); |
||||
inserter.flush(); |
||||
} |
||||
return id; |
||||
} |
||||
|
||||
private ObjectId insertSingleProposal(Repository git, |
||||
ObjectInserter inserter) throws IOException, NoOp { |
||||
// Fast path: tree is passed in with all proposals applied.
|
||||
ObjectId treeId = queuedTree.writeTree(inserter); |
||||
queuedTree = null; |
||||
leader.roundHoldsReferenceToRefTree = false; |
||||
|
||||
if (!ObjectId.zeroId().equals(acceptedOldIndex)) { |
||||
try (RevWalk rw = new RevWalk(git)) { |
||||
RevCommit c = rw.parseCommit(acceptedOldIndex); |
||||
if (treeId.equals(c.getTree())) { |
||||
throw new NoOp(); |
||||
} |
||||
} |
||||
} |
||||
|
||||
Proposal p = todo.get(0); |
||||
CommitBuilder b = new CommitBuilder(); |
||||
b.setTreeId(treeId); |
||||
if (!ObjectId.zeroId().equals(acceptedOldIndex)) { |
||||
b.setParentId(acceptedOldIndex); |
||||
} |
||||
b.setCommitter(leader.getSystem().newCommitter()); |
||||
b.setAuthor(p.getAuthor() != null ? p.getAuthor() : b.getCommitter()); |
||||
b.setMessage(message(p)); |
||||
return inserter.insert(b); |
||||
} |
||||
|
||||
private ObjectId insertMultiProposal(Repository git, |
||||
ObjectInserter inserter) throws IOException, NoOp { |
||||
// The tree was not passed in, or there are multiple proposals
|
||||
// each needing their own commit. Reset the tree and replay each
|
||||
// proposal in order as individual commits.
|
||||
ObjectId lastIndex = acceptedOldIndex; |
||||
ObjectId oldTreeId; |
||||
RefTree tree; |
||||
if (ObjectId.zeroId().equals(lastIndex)) { |
||||
oldTreeId = ObjectId.zeroId(); |
||||
tree = RefTree.newEmptyTree(); |
||||
} else { |
||||
try (RevWalk rw = new RevWalk(git)) { |
||||
RevCommit c = rw.parseCommit(lastIndex); |
||||
oldTreeId = c.getTree(); |
||||
tree = RefTree.read(rw.getObjectReader(), c.getTree()); |
||||
} |
||||
} |
||||
|
||||
PersonIdent committer = leader.getSystem().newCommitter(); |
||||
for (Proposal p : todo) { |
||||
if (!tree.apply(p.getCommands())) { |
||||
// This should not occur, previously during queuing the
|
||||
// commands were successfully applied to the pending tree.
|
||||
// Abort the entire round.
|
||||
throw new IOException( |
||||
KetchText.get().queuedProposalFailedToApply); |
||||
} |
||||
|
||||
ObjectId treeId = tree.writeTree(inserter); |
||||
if (treeId.equals(oldTreeId)) { |
||||
continue; |
||||
} |
||||
|
||||
CommitBuilder b = new CommitBuilder(); |
||||
b.setTreeId(treeId); |
||||
if (!ObjectId.zeroId().equals(lastIndex)) { |
||||
b.setParentId(lastIndex); |
||||
} |
||||
b.setAuthor(p.getAuthor() != null ? p.getAuthor() : committer); |
||||
b.setCommitter(committer); |
||||
b.setMessage(message(p)); |
||||
lastIndex = inserter.insert(b); |
||||
} |
||||
if (lastIndex.equals(acceptedOldIndex)) { |
||||
throw new NoOp(); |
||||
} |
||||
return lastIndex; |
||||
} |
||||
|
||||
private String message(Proposal p) { |
||||
StringBuilder m = new StringBuilder(); |
||||
String msg = p.getMessage(); |
||||
if (msg != null && !msg.isEmpty()) { |
||||
m.append(msg); |
||||
while (m.length() < 2 || m.charAt(m.length() - 2) != '\n' |
||||
|| m.charAt(m.length() - 1) != '\n') { |
||||
m.append('\n'); |
||||
} |
||||
} |
||||
m.append(KetchConstants.TERM.getName()) |
||||
.append(": ") //$NON-NLS-1$
|
||||
.append(leader.getTerm()); |
||||
return m.toString(); |
||||
} |
||||
|
||||
void abort() { |
||||
for (Proposal p : todo) { |
||||
p.abort(); |
||||
} |
||||
} |
||||
|
||||
void success() { |
||||
for (Proposal p : todo) { |
||||
p.success(); |
||||
} |
||||
} |
||||
|
||||
private List<ReceiveCommand> makeStageList(Repository git, |
||||
ObjectInserter inserter) throws IOException { |
||||
// For each branch, collapse consecutive updates to only most recent,
|
||||
// avoiding sending multiple objects in a rapid fast-forward chain, or
|
||||
// rewritten content.
|
||||
Map<String, ObjectId> byRef = new HashMap<>(); |
||||
for (Proposal p : todo) { |
||||
for (Command c : p.getCommands()) { |
||||
Ref n = c.getNewRef(); |
||||
if (n != null && !n.isSymbolic()) { |
||||
byRef.put(n.getName(), n.getObjectId()); |
||||
} |
||||
} |
||||
} |
||||
if (byRef.isEmpty()) { |
||||
return Collections.emptyList(); |
||||
} |
||||
|
||||
Set<ObjectId> newObjs = new HashSet<>(byRef.values()); |
||||
StageBuilder b = new StageBuilder( |
||||
leader.getSystem().getTxnStage(), |
||||
acceptedNewIndex); |
||||
return b.makeStageList(newObjs, git, inserter); |
||||
} |
||||
|
||||
|
||||
private static class NoOp extends Exception { |
||||
private static final long serialVersionUID = 1L; |
||||
} |
||||
} |
||||
@ -0,0 +1,316 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.internal.ketch.KetchReplica.CommitMethod.ALL_REFS; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.LOCK_FAILURE; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.NOT_ATTEMPTED; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.OK; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.REJECTED_NODELETE; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.REJECTED_NONFASTFORWARD; |
||||
import static org.eclipse.jgit.transport.ReceiveCommand.Result.REJECTED_OTHER_REASON; |
||||
import static org.eclipse.jgit.lib.Ref.Storage.NETWORK; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.ArrayList; |
||||
import java.util.Collection; |
||||
import java.util.Collections; |
||||
import java.util.LinkedHashMap; |
||||
import java.util.List; |
||||
import java.util.Map; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.errors.NotSupportedException; |
||||
import org.eclipse.jgit.errors.TransportException; |
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.lib.NullProgressMonitor; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.ObjectIdRef; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.transport.FetchConnection; |
||||
import org.eclipse.jgit.transport.PushConnection; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
import org.eclipse.jgit.transport.RemoteConfig; |
||||
import org.eclipse.jgit.transport.RemoteRefUpdate; |
||||
import org.eclipse.jgit.transport.Transport; |
||||
import org.eclipse.jgit.transport.URIish; |
||||
|
||||
/** |
||||
* Representation of a Git repository on a remote replica system. |
||||
* <p> |
||||
* {@link KetchLeader} will contact the replica using the Git wire protocol. |
||||
* <p> |
||||
* The remote replica may be fully Ketch-aware, or a standard Git server. |
||||
*/ |
||||
public class RemoteGitReplica extends KetchReplica { |
||||
private final URIish uri; |
||||
private final RemoteConfig remoteConfig; |
||||
|
||||
/** |
||||
* Configure a new remote. |
||||
* |
||||
* @param leader |
||||
* instance this replica follows. |
||||
* @param name |
||||
* unique-ish name identifying this remote for debugging. |
||||
* @param uri |
||||
* URI to connect to the follower's repository. |
||||
* @param cfg |
||||
* how Ketch should treat the remote system. |
||||
* @param rc |
||||
* optional remote configuration describing how to contact the |
||||
* peer repository. |
||||
*/ |
||||
public RemoteGitReplica(KetchLeader leader, String name, URIish uri, |
||||
ReplicaConfig cfg, @Nullable RemoteConfig rc) { |
||||
super(leader, name, cfg); |
||||
this.uri = uri; |
||||
this.remoteConfig = rc; |
||||
} |
||||
|
||||
/** @return URI to contact the remote peer repository. */ |
||||
public URIish getURI() { |
||||
return uri; |
||||
} |
||||
|
||||
/** @return optional configuration describing how to contact the peer. */ |
||||
@Nullable |
||||
protected RemoteConfig getRemoteConfig() { |
||||
return remoteConfig; |
||||
} |
||||
|
||||
@Override |
||||
protected String describeForLog() { |
||||
return String.format("%s @ %s", getName(), getURI()); //$NON-NLS-1$
|
||||
} |
||||
|
||||
@Override |
||||
protected void startPush(final ReplicaPushRequest req) { |
||||
getSystem().getExecutor().execute(new Runnable() { |
||||
@Override |
||||
public void run() { |
||||
try (Repository git = getLeader().openRepository()) { |
||||
try { |
||||
push(git, req); |
||||
req.done(git); |
||||
} catch (Throwable err) { |
||||
req.setException(git, err); |
||||
} |
||||
} catch (IOException err) { |
||||
req.setException(null, err); |
||||
} |
||||
} |
||||
}); |
||||
} |
||||
|
||||
private void push(Repository repo, ReplicaPushRequest req) |
||||
throws NotSupportedException, TransportException, IOException { |
||||
Map<String, Ref> adv; |
||||
List<RemoteCommand> cmds = asUpdateList(req.getCommands()); |
||||
try (Transport transport = Transport.open(repo, uri)) { |
||||
RemoteConfig rc = getRemoteConfig(); |
||||
if (rc != null) { |
||||
transport.applyConfig(rc); |
||||
} |
||||
transport.setPushAtomic(true); |
||||
adv = push(repo, transport, cmds); |
||||
} |
||||
for (RemoteCommand c : cmds) { |
||||
c.copyStatusToResult(); |
||||
} |
||||
req.setRefs(adv); |
||||
} |
||||
|
||||
private Map<String, Ref> push(Repository git, Transport transport, |
||||
List<RemoteCommand> cmds) throws IOException { |
||||
Map<String, RemoteRefUpdate> updates = asUpdateMap(cmds); |
||||
try (PushConnection connection = transport.openPush()) { |
||||
Map<String, Ref> adv = connection.getRefsMap(); |
||||
RemoteRefUpdate accepted = updates.get(getSystem().getTxnAccepted()); |
||||
if (accepted != null && !isExpectedValue(adv, accepted)) { |
||||
abort(cmds); |
||||
return adv; |
||||
} |
||||
|
||||
RemoteRefUpdate committed = updates.get(getSystem().getTxnCommitted()); |
||||
if (committed != null && !isExpectedValue(adv, committed)) { |
||||
abort(cmds); |
||||
return adv; |
||||
} |
||||
if (committed != null && getCommitMethod() == ALL_REFS) { |
||||
prepareCommit(git, cmds, updates, adv, |
||||
committed.getNewObjectId()); |
||||
} |
||||
|
||||
connection.push(NullProgressMonitor.INSTANCE, updates); |
||||
return adv; |
||||
} |
||||
} |
||||
|
||||
private static boolean isExpectedValue(Map<String, Ref> adv, |
||||
RemoteRefUpdate u) { |
||||
Ref r = adv.get(u.getRemoteName()); |
||||
if (!AnyObjectId.equals(getId(r), u.getExpectedOldObjectId())) { |
||||
((RemoteCommand) u).cmd.setResult(LOCK_FAILURE); |
||||
return false; |
||||
} |
||||
return true; |
||||
} |
||||
|
||||
private void prepareCommit(Repository git, List<RemoteCommand> cmds, |
||||
Map<String, RemoteRefUpdate> updates, Map<String, Ref> adv, |
||||
ObjectId committed) throws IOException { |
||||
for (ReceiveCommand cmd : prepareCommit(git, adv, committed)) { |
||||
RemoteCommand c = new RemoteCommand(cmd); |
||||
cmds.add(c); |
||||
updates.put(c.getRemoteName(), c); |
||||
} |
||||
} |
||||
|
||||
private static List<RemoteCommand> asUpdateList( |
||||
Collection<ReceiveCommand> cmds) { |
||||
try { |
||||
List<RemoteCommand> toPush = new ArrayList<>(cmds.size()); |
||||
for (ReceiveCommand cmd : cmds) { |
||||
toPush.add(new RemoteCommand(cmd)); |
||||
} |
||||
return toPush; |
||||
} catch (IOException e) { |
||||
// Cannot occur as no IO was required to build the command.
|
||||
throw new IllegalStateException(e); |
||||
} |
||||
} |
||||
|
||||
private static Map<String, RemoteRefUpdate> asUpdateMap( |
||||
List<RemoteCommand> cmds) { |
||||
Map<String, RemoteRefUpdate> m = new LinkedHashMap<>(); |
||||
for (RemoteCommand cmd : cmds) { |
||||
m.put(cmd.getRemoteName(), cmd); |
||||
} |
||||
return m; |
||||
} |
||||
|
||||
private static void abort(List<RemoteCommand> cmds) { |
||||
List<ReceiveCommand> tmp = new ArrayList<>(cmds.size()); |
||||
for (RemoteCommand cmd : cmds) { |
||||
tmp.add(cmd.cmd); |
||||
} |
||||
ReceiveCommand.abort(tmp); |
||||
} |
||||
|
||||
protected void blockingFetch(Repository repo, ReplicaFetchRequest req) |
||||
throws NotSupportedException, TransportException { |
||||
try (Transport transport = Transport.open(repo, uri)) { |
||||
RemoteConfig rc = getRemoteConfig(); |
||||
if (rc != null) { |
||||
transport.applyConfig(rc); |
||||
} |
||||
fetch(transport, req); |
||||
} |
||||
} |
||||
|
||||
private void fetch(Transport transport, ReplicaFetchRequest req) |
||||
throws NotSupportedException, TransportException { |
||||
try (FetchConnection conn = transport.openFetch()) { |
||||
Map<String, Ref> remoteRefs = conn.getRefsMap(); |
||||
req.setRefs(remoteRefs); |
||||
|
||||
List<Ref> want = new ArrayList<>(); |
||||
for (String name : req.getWantRefs()) { |
||||
Ref ref = remoteRefs.get(name); |
||||
if (ref != null && ref.getObjectId() != null) { |
||||
want.add(ref); |
||||
} |
||||
} |
||||
for (ObjectId id : req.getWantObjects()) { |
||||
want.add(new ObjectIdRef.Unpeeled(NETWORK, id.name(), id)); |
||||
} |
||||
|
||||
conn.fetch(NullProgressMonitor.INSTANCE, want, |
||||
Collections.<ObjectId> emptySet()); |
||||
} |
||||
} |
||||
|
||||
static class RemoteCommand extends RemoteRefUpdate { |
||||
final ReceiveCommand cmd; |
||||
|
||||
RemoteCommand(ReceiveCommand cmd) throws IOException { |
||||
super(null, null, |
||||
cmd.getNewId(), cmd.getRefName(), |
||||
true /* force update */, |
||||
null /* no local tracking ref */, |
||||
cmd.getOldId()); |
||||
this.cmd = cmd; |
||||
} |
||||
|
||||
void copyStatusToResult() { |
||||
if (cmd.getResult() == NOT_ATTEMPTED) { |
||||
switch (getStatus()) { |
||||
case OK: |
||||
case UP_TO_DATE: |
||||
case NON_EXISTING: |
||||
cmd.setResult(OK); |
||||
break; |
||||
|
||||
case REJECTED_NODELETE: |
||||
cmd.setResult(REJECTED_NODELETE); |
||||
break; |
||||
|
||||
case REJECTED_NONFASTFORWARD: |
||||
cmd.setResult(REJECTED_NONFASTFORWARD); |
||||
break; |
||||
|
||||
case REJECTED_OTHER_REASON: |
||||
cmd.setResult(REJECTED_OTHER_REASON, getMessage()); |
||||
break; |
||||
|
||||
default: |
||||
cmd.setResult(REJECTED_OTHER_REASON, getStatus().name()); |
||||
break; |
||||
} |
||||
} |
||||
} |
||||
} |
||||
} |
||||
@ -0,0 +1,233 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static java.util.concurrent.TimeUnit.DAYS; |
||||
import static java.util.concurrent.TimeUnit.HOURS; |
||||
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
||||
import static java.util.concurrent.TimeUnit.MINUTES; |
||||
import static java.util.concurrent.TimeUnit.SECONDS; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.CONFIG_KEY_COMMIT; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.CONFIG_KEY_SPEED; |
||||
import static org.eclipse.jgit.internal.ketch.KetchConstants.CONFIG_KEY_TYPE; |
||||
import static org.eclipse.jgit.lib.ConfigConstants.CONFIG_KEY_REMOTE; |
||||
|
||||
import java.util.Collections; |
||||
import java.util.HashMap; |
||||
import java.util.Map; |
||||
import java.util.concurrent.TimeUnit; |
||||
import java.util.regex.Matcher; |
||||
import java.util.regex.Pattern; |
||||
|
||||
import org.eclipse.jgit.internal.ketch.KetchReplica.CommitMethod; |
||||
import org.eclipse.jgit.internal.ketch.KetchReplica.CommitSpeed; |
||||
import org.eclipse.jgit.internal.ketch.KetchReplica.Participation; |
||||
import org.eclipse.jgit.lib.Config; |
||||
|
||||
/** Configures a {@link KetchReplica}. */ |
||||
public class ReplicaConfig { |
||||
/** |
||||
* Read a configuration from a config block. |
||||
* |
||||
* @param cfg |
||||
* configuration to read. |
||||
* @param name |
||||
* of the replica being configured. |
||||
* @return replica configuration for {@code name}. |
||||
*/ |
||||
public static ReplicaConfig newFromConfig(Config cfg, String name) { |
||||
return new ReplicaConfig().fromConfig(cfg, name); |
||||
} |
||||
|
||||
private Participation participation = Participation.FULL; |
||||
private CommitMethod commitMethod = CommitMethod.ALL_REFS; |
||||
private CommitSpeed commitSpeed = CommitSpeed.BATCHED; |
||||
private long minRetry = SECONDS.toMillis(5); |
||||
private long maxRetry = MINUTES.toMillis(1); |
||||
|
||||
/** @return participation of the replica in the system. */ |
||||
public Participation getParticipation() { |
||||
return participation; |
||||
} |
||||
|
||||
/** @return how Ketch should apply committed changes. */ |
||||
public CommitMethod getCommitMethod() { |
||||
return commitMethod; |
||||
} |
||||
|
||||
/** @return how quickly should Ketch commit. */ |
||||
public CommitSpeed getCommitSpeed() { |
||||
return commitSpeed; |
||||
} |
||||
|
||||
/** |
||||
* Returns the minimum wait delay before retrying a failure. |
||||
* |
||||
* @param unit |
||||
* to get retry delay in. |
||||
* @return minimum delay before retrying a failure. |
||||
*/ |
||||
public long getMinRetry(TimeUnit unit) { |
||||
return unit.convert(minRetry, MILLISECONDS); |
||||
} |
||||
|
||||
/** |
||||
* Returns the maximum wait delay before retrying a failure. |
||||
* |
||||
* @param unit |
||||
* to get retry delay in. |
||||
* @return maximum delay before retrying a failure. |
||||
*/ |
||||
public long getMaxRetry(TimeUnit unit) { |
||||
return unit.convert(maxRetry, MILLISECONDS); |
||||
} |
||||
|
||||
/** |
||||
* Update the configuration from a config block. |
||||
* |
||||
* @param cfg |
||||
* configuration to read. |
||||
* @param name |
||||
* of the replica being configured. |
||||
* @return {@code this} |
||||
*/ |
||||
public ReplicaConfig fromConfig(Config cfg, String name) { |
||||
participation = cfg.getEnum( |
||||
CONFIG_KEY_REMOTE, name, CONFIG_KEY_TYPE, |
||||
participation); |
||||
commitMethod = cfg.getEnum( |
||||
CONFIG_KEY_REMOTE, name, CONFIG_KEY_COMMIT, |
||||
commitMethod); |
||||
commitSpeed = cfg.getEnum( |
||||
CONFIG_KEY_REMOTE, name, CONFIG_KEY_SPEED, |
||||
commitSpeed); |
||||
minRetry = getMillis(cfg, name, "ketch-minRetry", minRetry); //$NON-NLS-1$
|
||||
maxRetry = getMillis(cfg, name, "ketch-maxRetry", maxRetry); //$NON-NLS-1$
|
||||
return this; |
||||
} |
||||
|
||||
private static long getMillis(Config cfg, String name, String key, |
||||
long defaultValue) { |
||||
String valStr = cfg.getString(CONFIG_KEY_REMOTE, name, key); |
||||
if (valStr == null) { |
||||
return defaultValue; |
||||
} |
||||
|
||||
valStr = valStr.trim(); |
||||
if (valStr.isEmpty()) { |
||||
return defaultValue; |
||||
} |
||||
|
||||
Matcher m = UnitMap.PATTERN.matcher(valStr); |
||||
if (!m.matches()) { |
||||
return defaultValue; |
||||
} |
||||
|
||||
String digits = m.group(1); |
||||
String unitName = m.group(2).trim(); |
||||
TimeUnit unit = UnitMap.UNITS.get(unitName); |
||||
if (unit == null) { |
||||
return defaultValue; |
||||
} |
||||
|
||||
try { |
||||
if (digits.indexOf('.') == -1) { |
||||
return unit.toMillis(Long.parseLong(digits)); |
||||
} |
||||
|
||||
double val = Double.parseDouble(digits); |
||||
return (long) (val * unit.toMillis(1)); |
||||
} catch (NumberFormatException nfe) { |
||||
return defaultValue; |
||||
} |
||||
} |
||||
|
||||
static class UnitMap { |
||||
static final Pattern PATTERN = Pattern |
||||
.compile("^([1-9][0-9]*(?:\\.[0-9]*)?)\\s*(.*)$"); //$NON-NLS-1$
|
||||
|
||||
static final Map<String, TimeUnit> UNITS; |
||||
|
||||
static { |
||||
Map<String, TimeUnit> m = new HashMap<>(); |
||||
TimeUnit u = MILLISECONDS; |
||||
m.put("", u); //$NON-NLS-1$
|
||||
m.put("ms", u); //$NON-NLS-1$
|
||||
m.put("millis", u); //$NON-NLS-1$
|
||||
m.put("millisecond", u); //$NON-NLS-1$
|
||||
m.put("milliseconds", u); //$NON-NLS-1$
|
||||
|
||||
u = SECONDS; |
||||
m.put("s", u); //$NON-NLS-1$
|
||||
m.put("sec", u); //$NON-NLS-1$
|
||||
m.put("secs", u); //$NON-NLS-1$
|
||||
m.put("second", u); //$NON-NLS-1$
|
||||
m.put("seconds", u); //$NON-NLS-1$
|
||||
|
||||
u = MINUTES; |
||||
m.put("m", u); //$NON-NLS-1$
|
||||
m.put("min", u); //$NON-NLS-1$
|
||||
m.put("mins", u); //$NON-NLS-1$
|
||||
m.put("minute", u); //$NON-NLS-1$
|
||||
m.put("minutes", u); //$NON-NLS-1$
|
||||
|
||||
u = HOURS; |
||||
m.put("h", u); //$NON-NLS-1$
|
||||
m.put("hr", u); //$NON-NLS-1$
|
||||
m.put("hrs", u); //$NON-NLS-1$
|
||||
m.put("hour", u); //$NON-NLS-1$
|
||||
m.put("hours", u); //$NON-NLS-1$
|
||||
|
||||
u = DAYS; |
||||
m.put("d", u); //$NON-NLS-1$
|
||||
m.put("day", u); //$NON-NLS-1$
|
||||
m.put("days", u); //$NON-NLS-1$
|
||||
|
||||
UNITS = Collections.unmodifiableMap(m); |
||||
} |
||||
|
||||
private UnitMap() { |
||||
} |
||||
} |
||||
} |
||||
@ -0,0 +1,96 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import java.util.Map; |
||||
import java.util.Set; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
|
||||
/** A fetch request to obtain objects from a replica, and its result. */ |
||||
public class ReplicaFetchRequest { |
||||
private final Set<String> wantRefs; |
||||
private final Set<ObjectId> wantObjects; |
||||
private Map<String, Ref> refs; |
||||
|
||||
/** |
||||
* Construct a new fetch request for a replica. |
||||
* |
||||
* @param wantRefs |
||||
* named references to be fetched. |
||||
* @param wantObjects |
||||
* specific objects to be fetched. |
||||
*/ |
||||
public ReplicaFetchRequest(Set<String> wantRefs, |
||||
Set<ObjectId> wantObjects) { |
||||
this.wantRefs = wantRefs; |
||||
this.wantObjects = wantObjects; |
||||
} |
||||
|
||||
/** @return references to be fetched. */ |
||||
public Set<String> getWantRefs() { |
||||
return wantRefs; |
||||
} |
||||
|
||||
/** @return objects to be fetched. */ |
||||
public Set<ObjectId> getWantObjects() { |
||||
return wantObjects; |
||||
} |
||||
|
||||
/** @return remote references, usually from the advertisement. */ |
||||
@Nullable |
||||
public Map<String, Ref> getRefs() { |
||||
return refs; |
||||
} |
||||
|
||||
/** |
||||
* @param refs |
||||
* references observed from the replica. |
||||
*/ |
||||
public void setRefs(Map<String, Ref> refs) { |
||||
this.refs = refs; |
||||
} |
||||
} |
||||
@ -0,0 +1,168 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import java.util.Collection; |
||||
import java.util.Map; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.Ref; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** |
||||
* A push request sending objects to a replica, and its result. |
||||
* <p> |
||||
* Implementors of {@link KetchReplica} must populate the command result fields, |
||||
* {@link #setRefs(Map)}, and call one of |
||||
* {@link #setException(Repository, Throwable)} or {@link #done(Repository)} to |
||||
* finish processing. |
||||
*/ |
||||
public class ReplicaPushRequest { |
||||
private final KetchReplica replica; |
||||
private final Collection<ReceiveCommand> commands; |
||||
private Map<String, Ref> refs; |
||||
private Throwable exception; |
||||
private boolean notified; |
||||
|
||||
/** |
||||
* Construct a new push request for a replica. |
||||
* |
||||
* @param replica |
||||
* the replica being pushed to. |
||||
* @param commands |
||||
* commands to be executed. |
||||
*/ |
||||
public ReplicaPushRequest(KetchReplica replica, |
||||
Collection<ReceiveCommand> commands) { |
||||
this.replica = replica; |
||||
this.commands = commands; |
||||
} |
||||
|
||||
/** @return commands to be executed, and their results. */ |
||||
public Collection<ReceiveCommand> getCommands() { |
||||
return commands; |
||||
} |
||||
|
||||
/** @return remote references, usually from the advertisement. */ |
||||
@Nullable |
||||
public Map<String, Ref> getRefs() { |
||||
return refs; |
||||
} |
||||
|
||||
/** |
||||
* @param refs |
||||
* references observed from the replica. |
||||
*/ |
||||
public void setRefs(Map<String, Ref> refs) { |
||||
this.refs = refs; |
||||
} |
||||
|
||||
/** @return exception thrown, if any. */ |
||||
@Nullable |
||||
public Throwable getException() { |
||||
return exception; |
||||
} |
||||
|
||||
/** |
||||
* Mark the request as crashing with a communication error. |
||||
* <p> |
||||
* This method may take significant time acquiring the leader lock and |
||||
* updating the Ketch state machine with the failure. |
||||
* |
||||
* @param repo |
||||
* local repository reference used by the push attempt. |
||||
* @param err |
||||
* exception thrown during communication. |
||||
*/ |
||||
public void setException(@Nullable Repository repo, Throwable err) { |
||||
if (KetchReplica.log.isErrorEnabled()) { |
||||
KetchReplica.log.error(describe("failed"), err); //$NON-NLS-1$
|
||||
} |
||||
if (!notified) { |
||||
notified = true; |
||||
exception = err; |
||||
replica.afterPush(repo, this); |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Mark the request as completed without exception. |
||||
* <p> |
||||
* This method may take significant time acquiring the leader lock and |
||||
* updating the Ketch state machine with results from this replica. |
||||
* |
||||
* @param repo |
||||
* local repository reference used by the push attempt. |
||||
*/ |
||||
public void done(Repository repo) { |
||||
if (KetchReplica.log.isDebugEnabled()) { |
||||
KetchReplica.log.debug(describe("completed")); //$NON-NLS-1$
|
||||
} |
||||
if (!notified) { |
||||
notified = true; |
||||
replica.afterPush(repo, this); |
||||
} |
||||
} |
||||
|
||||
private String describe(String heading) { |
||||
StringBuilder b = new StringBuilder(); |
||||
b.append("push to "); //$NON-NLS-1$
|
||||
b.append(replica.describeForLog()); |
||||
b.append(' ').append(heading).append(":\n"); //$NON-NLS-1$
|
||||
for (ReceiveCommand cmd : commands) { |
||||
b.append(String.format( |
||||
" %-12s %-12s %s %s", //$NON-NLS-1$
|
||||
LeaderSnapshot.str(cmd.getOldId()), |
||||
LeaderSnapshot.str(cmd.getNewId()), |
||||
cmd.getRefName(), |
||||
cmd.getResult())); |
||||
if (cmd.getMessage() != null) { |
||||
b.append(' ').append(cmd.getMessage()); |
||||
} |
||||
b.append('\n'); |
||||
} |
||||
return b.toString(); |
||||
} |
||||
} |
||||
@ -0,0 +1,109 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import java.util.Date; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
|
||||
/** |
||||
* A snapshot of a replica. |
||||
* |
||||
* @see LeaderSnapshot |
||||
*/ |
||||
public class ReplicaSnapshot { |
||||
final KetchReplica replica; |
||||
ObjectId accepted; |
||||
ObjectId committed; |
||||
KetchReplica.State state; |
||||
String error; |
||||
long retryAtMillis; |
||||
|
||||
ReplicaSnapshot(KetchReplica replica) { |
||||
this.replica = replica; |
||||
} |
||||
|
||||
/** @return the replica this snapshot describes the state of. */ |
||||
public KetchReplica getReplica() { |
||||
return replica; |
||||
} |
||||
|
||||
/** @return current state of the replica. */ |
||||
public KetchReplica.State getState() { |
||||
return state; |
||||
} |
||||
|
||||
/** @return last known Git commit at {@code refs/txn/accepted}. */ |
||||
@Nullable |
||||
public ObjectId getAccepted() { |
||||
return accepted; |
||||
} |
||||
|
||||
/** @return last known Git commit at {@code refs/txn/committed}. */ |
||||
@Nullable |
||||
public ObjectId getCommitted() { |
||||
return committed; |
||||
} |
||||
|
||||
/** |
||||
* @return if {@link #getState()} == {@link KetchReplica.State#OFFLINE} an |
||||
* optional human-readable message from the transport system |
||||
* explaining the failure. |
||||
*/ |
||||
@Nullable |
||||
public String getErrorMessage() { |
||||
return error; |
||||
} |
||||
|
||||
/** |
||||
* @return time (usually in the future) when the leader will retry |
||||
* communication with the offline or lagging replica; null if no |
||||
* retry is scheduled or necessary. |
||||
*/ |
||||
@Nullable |
||||
public Date getRetryAt() { |
||||
return retryAtMillis > 0 ? new Date(retryAtMillis) : null; |
||||
} |
||||
} |
||||
@ -0,0 +1,116 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.List; |
||||
|
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
|
||||
/** |
||||
* One round-trip to all replicas proposing a log entry. |
||||
* <p> |
||||
* In Raft a log entry represents a state transition at a specific index in the |
||||
* replicated log. The leader can only append log entries to the log. |
||||
* <p> |
||||
* In Ketch a log entry is recorded under the {@code refs/txn} namespace. This |
||||
* occurs when: |
||||
* <ul> |
||||
* <li>a replica wants to establish itself as a new leader by proposing a new |
||||
* term (see {@link ElectionRound}) |
||||
* <li>an established leader wants to gain consensus on new {@link Proposal}s |
||||
* (see {@link ProposalRound}) |
||||
* </ul> |
||||
*/ |
||||
abstract class Round { |
||||
final KetchLeader leader; |
||||
final LogIndex acceptedOldIndex; |
||||
LogIndex acceptedNewIndex; |
||||
List<ReceiveCommand> stageCommands; |
||||
|
||||
Round(KetchLeader leader, LogIndex head) { |
||||
this.leader = leader; |
||||
this.acceptedOldIndex = head; |
||||
} |
||||
|
||||
/** |
||||
* Creates a commit for {@code refs/txn/accepted} and calls |
||||
* {@link #runAsync(AnyObjectId)} to begin execution of the round across |
||||
* the system. |
||||
* <p> |
||||
* If references are being updated (such as in a {@link ProposalRound}) the |
||||
* RefTree may be modified. |
||||
* <p> |
||||
* Invoked without {@link KetchLeader#lock} to build objects. |
||||
* |
||||
* @throws IOException |
||||
* the round cannot build new objects within the leader's |
||||
* repository. The leader may be unable to execute. |
||||
*/ |
||||
abstract void start() throws IOException; |
||||
|
||||
/** |
||||
* Asynchronously distribute the round's new value for |
||||
* {@code refs/txn/accepted} to all replicas. |
||||
* <p> |
||||
* Invoked by {@link #start()} after new commits have been created for the |
||||
* log. The method passes {@code newId} to {@link KetchLeader} to be |
||||
* distributed to all known replicas. |
||||
* |
||||
* @param newId |
||||
* new value for {@code refs/txn/accepted}. |
||||
*/ |
||||
void runAsync(AnyObjectId newId) { |
||||
acceptedNewIndex = acceptedOldIndex.nextIndex(newId); |
||||
leader.runAsync(this); |
||||
} |
||||
|
||||
/** |
||||
* Notify the round it was accepted by a majority of the system. |
||||
* <p> |
||||
* Invoked by the leader with {@link KetchLeader#lock} held by the caller. |
||||
*/ |
||||
abstract void success(); |
||||
} |
||||
@ -0,0 +1,270 @@
|
||||
/* |
||||
* Copyright (C) 2016, Google Inc. |
||||
* and other copyright owners as documented in the project's IP log. |
||||
* |
||||
* This program and the accompanying materials are made available |
||||
* under the terms of the Eclipse Distribution License v1.0 which |
||||
* accompanies this distribution, is reproduced below, and is |
||||
* available at http://www.eclipse.org/org/documents/edl-v10.php
|
||||
* |
||||
* All rights reserved. |
||||
* |
||||
* Redistribution and use in source and binary forms, with or |
||||
* without modification, are permitted provided that the following |
||||
* conditions are met: |
||||
* |
||||
* - Redistributions of source code must retain the above copyright |
||||
* notice, this list of conditions and the following disclaimer. |
||||
* |
||||
* - Redistributions in binary form must reproduce the above |
||||
* copyright notice, this list of conditions and the following |
||||
* disclaimer in the documentation and/or other materials provided |
||||
* with the distribution. |
||||
* |
||||
* - Neither the name of the Eclipse Foundation, Inc. nor the |
||||
* names of its contributors may be used to endorse or promote |
||||
* products derived from this software without specific prior |
||||
* written permission. |
||||
* |
||||
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND |
||||
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, |
||||
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
||||
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
||||
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
||||
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
||||
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
||||
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
||||
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
||||
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
||||
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
||||
*/ |
||||
|
||||
package org.eclipse.jgit.internal.ketch; |
||||
|
||||
import static org.eclipse.jgit.lib.FileMode.TYPE_GITLINK; |
||||
|
||||
import java.io.IOException; |
||||
import java.util.ArrayList; |
||||
import java.util.HashSet; |
||||
import java.util.List; |
||||
import java.util.Set; |
||||
|
||||
import org.eclipse.jgit.annotations.Nullable; |
||||
import org.eclipse.jgit.lib.AnyObjectId; |
||||
import org.eclipse.jgit.lib.CommitBuilder; |
||||
import org.eclipse.jgit.lib.ObjectId; |
||||
import org.eclipse.jgit.lib.ObjectInserter; |
||||
import org.eclipse.jgit.lib.PersonIdent; |
||||
import org.eclipse.jgit.lib.Repository; |
||||
import org.eclipse.jgit.revwalk.RevCommit; |
||||
import org.eclipse.jgit.revwalk.RevObject; |
||||
import org.eclipse.jgit.revwalk.RevWalk; |
||||
import org.eclipse.jgit.transport.ReceiveCommand; |
||||
import org.eclipse.jgit.treewalk.EmptyTreeIterator; |
||||
import org.eclipse.jgit.treewalk.TreeWalk; |
||||
import org.eclipse.jgit.treewalk.filter.TreeFilter; |
||||
|
||||
/** Constructs a set of commands to stage content during a proposal. */ |
||||
public class StageBuilder { |
||||
/** |
||||
* Acceptable number of references to send in a single stage transaction. |
||||
* <p> |
||||
* If the number of unique objects exceeds this amount the builder will |
||||
* attempt to decrease the reference count by chaining commits.. |
||||
*/ |
||||
private static final int SMALL_BATCH_SIZE = 5; |
||||
|
||||
/** |
||||
* Acceptable number of commits to chain together using parent pointers. |
||||
* <p> |
||||
* When staging many unique commits the {@link StageBuilder} batches |
||||
* together unrelated commits as parents of a temporary commit. After the |
||||
* proposal completes the temporary commit is discarded and can be garbage |
||||
* collected by all replicas. |
||||
*/ |
||||
private static final int TEMP_PARENT_BATCH_SIZE = 128; |
||||
|
||||
private static final byte[] PEEL = { ' ', '^' }; |
||||
|
||||
private final String txnStage; |
||||
private final String txnId; |
||||
|
||||
/** |
||||
* Construct a stage builder for a transaction. |
||||
* |
||||
* @param txnStageNamespace |
||||
* namespace for transaction references to build |
||||
* {@code "txnStageNamespace/txnId.n"} style names. |
||||
* @param txnId |
||||
* identifier used to name temporary staging refs. |
||||
*/ |
||||
public StageBuilder(String txnStageNamespace, ObjectId txnId) { |
||||
this.txnStage = txnStageNamespace; |
||||
this.txnId = txnId.name(); |
||||
} |
||||
|
||||
/** |
||||
* Compare two RefTrees and return commands to stage new objects. |
||||
* <p> |
||||
* This method ignores the lineage between the two RefTrees and does a |
||||
* straight diff on the two trees. New objects will be staged. The diff |
||||
* strategy is useful to catch-up a lagging replica, without sending every |
||||
* intermediate step. This may mean the replica does not have the same |
||||
* object set as other replicas if there are rewinds or branch deletes. |
||||
* |
||||
* @param git |
||||
* source repository to read {@code oldTree} and {@code newTree} |
||||
* from. |
||||
* @param oldTree |
||||
* accepted RefTree on the replica ({@code refs/txn/accepted}). |
||||
* Use {@link ObjectId#zeroId()} if the remote does not have any |
||||
* ref tree, e.g. a new replica catching up. |
||||
* @param newTree |
||||
* RefTree being sent to the replica. The trees will be compared. |
||||
* @return list of commands to create {@code "refs/txn/stage/..."} |
||||
* references on replicas anchoring new objects into the repository |
||||
* while a transaction gains consensus. |
||||
* @throws IOException |
||||
* {@code git} cannot be accessed to compare {@code oldTree} and |
||||
* {@code newTree} to build the object set. |
||||
*/ |
||||
public List<ReceiveCommand> makeStageList(Repository git, ObjectId oldTree, |
||||
ObjectId newTree) throws IOException { |
||||
try (RevWalk rw = new RevWalk(git); |
||||
TreeWalk tw = new TreeWalk(rw.getObjectReader()); |
||||
ObjectInserter ins = git.newObjectInserter()) { |
||||
if (AnyObjectId.equals(oldTree, ObjectId.zeroId())) { |
||||
tw.addTree(new EmptyTreeIterator()); |
||||
} else { |
||||
tw.addTree(rw.parseTree(oldTree)); |
||||
} |
||||
tw.addTree(rw.parseTree(newTree)); |
||||
tw.setFilter(TreeFilter.ANY_DIFF); |
||||
tw.setRecursive(true); |
||||
|
||||
Set<ObjectId> newObjs = new HashSet<>(); |
||||
while (tw.next()) { |
||||
if (tw.getRawMode(1) == TYPE_GITLINK |
||||
&& !tw.isPathSuffix(PEEL, 2)) { |
||||
newObjs.add(tw.getObjectId(1)); |
||||
} |
||||
} |
||||
|
||||
List<ReceiveCommand> cmds = makeStageList(newObjs, git, ins); |
||||
ins.flush(); |
||||
return cmds; |
||||
} |
||||
} |
||||
|
||||
/** |
||||
* Construct a set of commands to stage objects on a replica. |
||||
* |
||||
* @param newObjs |
||||
* objects to send to a replica. |
||||
* @param git |
||||
* local repository to read source objects from. Required to |
||||
* perform minification of {@code newObjs}. |
||||
* @param inserter |
||||
* inserter to write temporary commit objects during minification |
||||
* if many new branches are created by {@code newObjs}. |
||||
* @return list of commands to create {@code "refs/txn/stage/..."} |
||||
* references on replicas anchoring {@code newObjs} into the |
||||
* repository while a transaction gains consensus. |
||||
* @throws IOException |
||||
* {@code git} cannot be accessed to perform minification of |
||||
* {@code newObjs}. |
||||
*/ |
||||
public List<ReceiveCommand> makeStageList(Set<ObjectId> newObjs, |
||||
@Nullable Repository git, @Nullable ObjectInserter inserter) |
||||
throws IOException { |
||||
if (git == null || newObjs.size() <= SMALL_BATCH_SIZE) { |
||||
// Without a source repository can only construct unique set.
|
||||
List<ReceiveCommand> cmds = new ArrayList<>(newObjs.size()); |
||||
for (ObjectId id : newObjs) { |
||||
stage(cmds, id); |
||||
} |
||||
return cmds; |
||||
} |
||||
|
||||
List<ReceiveCommand> cmds = new ArrayList<>(); |
||||
List<RevCommit> commits = new ArrayList<>(); |
||||
reduceObjects(cmds, commits, git, newObjs); |
||||
|
||||
if (inserter == null || commits.size() <= 1 |
||||
|| (cmds.size() + commits.size()) <= SMALL_BATCH_SIZE) { |
||||
// Without an inserter to aggregate commits, or for a small set of
|
||||
// commits just send one stage ref per commit.
|
||||
for (RevCommit c : commits) { |
||||
stage(cmds, c.copy()); |
||||
} |
||||
return cmds; |
||||
} |
||||
|
||||
// 'commits' is sorted most recent to least recent commit.
|
||||
// Group batches of commits and build a chain.
|
||||
// TODO(sop) Cluster by restricted graphs to support filtering.
|
||||
ObjectId tip = null; |
||||
for (int end = commits.size(); end > 0;) { |
||||
int start = Math.max(0, end - TEMP_PARENT_BATCH_SIZE); |
||||
List<RevCommit> batch = commits.subList(start, end); |
||||
List<ObjectId> parents = new ArrayList<>(1 + batch.size()); |
||||
if (tip != null) { |
||||
parents.add(tip); |
||||
} |
||||
parents.addAll(batch); |
||||
|
||||
CommitBuilder b = new CommitBuilder(); |
||||
b.setTreeId(batch.get(0).getTree()); |
||||
b.setParentIds(parents); |
||||
b.setAuthor(tmpAuthor(batch)); |
||||
b.setCommitter(b.getAuthor()); |
||||
tip = inserter.insert(b); |
||||
end = start; |
||||
} |
||||
stage(cmds, tip); |
||||
return cmds; |
||||
} |
||||
|
||||
private static PersonIdent tmpAuthor(List<RevCommit> commits) { |
||||
// Construct a predictable author using most recent commit time.
|
||||
int t = 0; |
||||
for (int i = 0; i < commits.size();) { |
||||
t = Math.max(t, commits.get(i).getCommitTime()); |
||||
} |
||||
String name = "Ketch Stage"; //$NON-NLS-1$
|
||||
String email = "tmp@tmp"; //$NON-NLS-1$
|
||||
return new PersonIdent(name, email, t * 1000L, 0); |
||||
} |
||||
|
||||
private void reduceObjects(List<ReceiveCommand> cmds, |
||||
List<RevCommit> commits, Repository git, |
||||
Set<ObjectId> newObjs) throws IOException { |
||||
try (RevWalk rw = new RevWalk(git)) { |
||||
rw.setRetainBody(false); |
||||
|
||||
for (ObjectId id : newObjs) { |
||||
RevObject obj = rw.parseAny(id); |
||||
if (obj instanceof RevCommit) { |
||||
rw.markStart((RevCommit) obj); |
||||
} else { |
||||
stage(cmds, id); |
||||
} |
||||
} |
||||
|
||||
for (RevCommit c; (c = rw.next()) != null;) { |
||||
commits.add(c); |
||||
rw.markUninteresting(c); |
||||
} |
||||
} |
||||
} |
||||
|
||||
private void stage(List<ReceiveCommand> cmds, ObjectId id) { |
||||
int estLen = txnStage.length() + txnId.length() + 5; |
||||
StringBuilder n = new StringBuilder(estLen); |
||||
n.append(txnStage).append(txnId).append('.'); |
||||
n.append(Integer.toHexString(cmds.size())); |
||||
cmds.add(new ReceiveCommand(ObjectId.zeroId(), id, n.toString())); |
||||
} |
||||
} |
||||
@ -0,0 +1,4 @@
|
||||
/** |
||||
* Distributed consensus system built on Git. |
||||
*/ |
||||
package org.eclipse.jgit.internal.ketch; |
||||
Loading…
Reference in new issue