Add cache for queries with ID

models/article.ts

@@ -9,6 +9,8 @@ declare var syzoj: any;
 
 @TypeORM.Entity()
 export default class Article extends Model {
+  static cache = true;
+
   @TypeORM.PrimaryGeneratedColumn()
   id: number;
 

models/common.ts

@@ -1,4 +1,6 @@
 import * as TypeORM from "typeorm";
+import * as LRUCache from "lru-cache";
+import * as ObjectAssignDeep from "object-assign-deep";
 
 interface Paginater {
   pageCnt: number;
@@ -6,13 +8,74 @@ interface Paginater {
   currPage: number;
 }
 
+const caches: Map<string, LRUCache<number, Model>> = new Map();
+
+function ensureCache(modelName) {
+  if (!caches.has(modelName)) {
+    caches.set(modelName, new LRUCache({
+      max: 500
+    }));
+  }
+
+  return caches.get(modelName);
+}
+
+function cacheGet(modelName, id) {
+  return ensureCache(modelName).get(parseInt(id));
+}
+
+function cacheSet(modelName, id, data) {
+  if (data == null) {
+    ensureCache(modelName).del(id);
+  } else {
+    ensureCache(modelName).set(parseInt(id), data);
+  }
+}
+
 export default class Model extends TypeORM.BaseEntity {
+  static cache = false;
+
   static async findById<T extends TypeORM.BaseEntity>(this: TypeORM.ObjectType<T>, id?: number): Promise<T | undefined> {
-    return await (this as any).findOne(parseInt(id as any) || 0);
+    const doQuery = async () => await (this as any).findOne(parseInt(id as any) || 0);
+
+    if ((this as typeof Model).cache) {
+      let result;
+      if (result = cacheGet(this.name, id)) {
+        // Got cached result.
+        // Return a copy of it to avoid issue of adding or assigning properties.
+        const object = {};
+        Object.keys(result).forEach(key => {
+          object[key] = result[key] && typeof result[key] === 'object'
+                      ? ObjectAssignDeep({}, result[key])
+                      : result[key];
+        });
+        return (this as typeof Model).create<T>(object);
+      }
+
+      result = await doQuery();
+      if (result) {
+        cacheSet(this.name, id, result);
+      }
+      return result;
+    } else {
+      return await doQuery();
+    }
   }
 
   async destroy() {
+    const id = (this as any).id;
     await TypeORM.getManager().remove(this);
+    if ((this.constructor as typeof Model).cache) {
+      cacheSet(this.constructor.name, id, null);
+    }
+  }
+
+  async save(): Promise<this> {
+    await super.save();
+    if ((this.constructor as typeof Model).cache) {
+      cacheSet(this.constructor.name, (this as any).id, this);
+    }
+    return this;
   }
 
   static async countQuery<T extends TypeORM.BaseEntity>(this: TypeORM.ObjectType<T>, query: TypeORM.SelectQueryBuilder<T> | string) {

models/contest.ts

@@ -16,6 +16,8 @@ enum ContestType {
 
 @TypeORM.Entity()
 export default class Contest extends Model {
+  static cache = true;
+
   @TypeORM.PrimaryGeneratedColumn()
   id: number;
 

models/problem.ts

@@ -200,6 +200,8 @@ enum ProblemType {
 
 @TypeORM.Entity()
 export default class Problem extends Model {
+  static cache = true;
+
   @TypeORM.PrimaryGeneratedColumn()
   id: number;
 

models/problem_tag.ts

@@ -3,6 +3,8 @@ import Model from "./common";
 
 @TypeORM.Entity()
 export default class ProblemTag extends Model {
+  static cache = true;
+
   @TypeORM.PrimaryGeneratedColumn()
   id: number;
 

models/user.ts

@@ -9,6 +9,8 @@ import Article from "./article";
 
 @TypeORM.Entity()
 export default class User extends Model {
+  static cache = true;
+
   @TypeORM.PrimaryGeneratedColumn()
   id: number;
 

package.json

@@ -25,6 +25,7 @@
   "homepage": "https://github.com/syzoj/syzoj#readme",
   "dependencies": {
     "@types/fs-extra": "^5.0.5",
+    "@types/lru-cache": "^5.1.0",
     "ansi-to-html": "^0.6.10",
     "async-lock": "^1.2.0",
     "bluebird": "^3.5.4",
@@ -45,6 +46,7 @@
     "jsdom": "^14.0.0",
     "jsondiffpatch": "0.2.5",
     "jsonwebtoken": "^8.5.1",
+    "lru-cache": "^5.1.1",
     "mariadb": "^2.0.3",
     "moment": "^2.24.0",
     "msgpack-lite": "^0.1.26",

yarn.lock

@@ -14,6 +14,11 @@
   dependencies:
     "@types/node" "*"
 
+"@types/lru-cache@^5.1.0":
+  version "5.1.0"
+  resolved "https://registry.yarnpkg.com/@types/lru-cache/-/lru-cache-5.1.0.tgz#57f228f2b80c046b4a1bd5cac031f81f207f4f03"
+  integrity sha512-RaE0B+14ToE4l6UqdarKPnXwVDuigfFv+5j9Dze/Nqr23yyuqdNvzcZi3xB+3Agvi5R4EOgAksfv3lXX4vBt9w==
+
 "@types/node@*":
   version "11.11.4"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-11.11.4.tgz#8808bd5a82bbf6f5d412eff1c228d178e7c24bb3"
@@ -2135,6 +2140,13 @@ lru-cache@^4.0.1, lru-cache@^4.1.3:
     pseudomap "^1.0.2"
     yallist "^2.1.2"
 
+lru-cache@^5.1.1:
+  version "5.1.1"
+  resolved "https://registry.yarnpkg.com/lru-cache/-/lru-cache-5.1.1.tgz#1da27e6710271947695daf6848e847f01d84b920"
+  integrity sha512-KpNARQA3Iwv+jTA0utUVVbrh+Jlrr1Fv0e56GGzAFOXN7dk/FviaDW8LHmK52DlcH4WP2n6gI8vN1aesBFgo9w==
+  dependencies:
+    yallist "^3.0.2"
+
 mailcomposer@^3.12.0:
   version "3.12.0"
   resolved "https://registry.yarnpkg.com/mailcomposer/-/mailcomposer-3.12.0.tgz#9c5e1188aa8e1c62ec8b86bd43468102b639e8f9"
@@ -3842,6 +3854,11 @@ yallist@^2.1.2:
   resolved "https://registry.yarnpkg.com/yallist/-/yallist-2.1.2.tgz#1c11f9218f076089a47dd512f93c6699a6a81d52"
   integrity sha1-HBH5IY8HYImkfdUS+TxmmaaoHVI=
 
+yallist@^3.0.2:
+  version "3.0.3"
+  resolved "https://registry.yarnpkg.com/yallist/-/yallist-3.0.3.tgz#b4b049e314be545e3ce802236d6cd22cd91c3de9"
+  integrity sha512-S+Zk8DEWE6oKpV+vI3qWkaK+jSbIK86pCwe2IF/xwIpQ8jEuxpw9NyaGjmp9+BoJv5FV2piqCDcoCtStppiq2A==
+
 yargonaut@^1.1.2:
   version "1.1.4"
   resolved "https://registry.yarnpkg.com/yargonaut/-/yargonaut-1.1.4.tgz#c64f56432c7465271221f53f5cc517890c3d6e0c"