DolphinScheduler/dolphinscheduler-python/pydolphinscheduler/docs/source/resources_plugin/resource-plugin.rst

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ResourcePlugin
==============

`ResourcePlugin` is an abstract class of resource plug-in parameters of task subclass and workflow.
All resource plugins need to inherit and override its abstract methods.

Code
----
.. literalinclude:: ../../../src/pydolphinscheduler/core/resource_plugin.py
   :start-after: [start resource_plugin_definition]
   :end-before: [end resource_plugin_definition]

Dive Into
---------
It has the following key functions.

- Method `__init__`: The `__init__` function has STR type parameter `prefix`, which means the prefix of the resource.

You can rewrite this function if necessary.

.. literalinclude:: ../../../src/pydolphinscheduler/core/resource_plugin.py
    :start-after: [start init_method]
    :end-before: [end init_method]

- Method `read_file`: Get content from the given URI, The function parameter is the suffix of the file path.

The file prefix has been initialized in init of the resource plug-in.

The prefix plus suffix is the absolute path of the file in this resource.

It is an abstract function. You must rewrite it

.. literalinclude:: ../../../src/pydolphinscheduler/core/resource_plugin.py
    :start-after: [start abstractmethod read_file]
    :end-before: [end abstractmethod read_file]

.. automodule:: pydolphinscheduler.core.resource_plugin

How to use
----------
Resource plugin can be used in task subclasses and workflows. You can use the resource plugin by adding the `resource_plugin` parameter when they are initialized.
For example, local resource plugin, add `resource_plugin = Local("/tmp")`.

The resource plugin we currently support are `local`, `github`.

Here is an example.

.. literalinclude:: ../../../src/pydolphinscheduler/examples/tutorial_resource_plugin.py
   :start-after: [start workflow_declare]
   :end-before: [end task_declare]

When the resource_plugin parameter is defined in both the task subclass and the workflow, the resource_plugin defined in the task subclass is used first.

If the task subclass does not define resource_plugin, but the resource_plugin is defined in the workflow, the resource_plugin in the workflow is used.

Of course, if neither the task subclass nor the workflow specifies resource_plugin, the command at this time will be executed as a script,

in other words, we are forward compatible.