More friendly output of the airflow plugins command + add timetables

[mik-laj]

I suggest introducing a few improvements to this command, as this command does not always do the job:

• The flask blueprints field contains information about the name and the imported name to distinguish between different objects.
• Full import paths for classes are shown to easily identify the class. In particular, I want the executor field to show the full name so that it can be easily set in the configuration file.
• The method output is deterministic, so it's easier to use. Users don't care about object memory addresses.

Before:

$ AIRFLOW__CORE__PLUGINS_FOLDER=$PWD/tests/plugins airflow plugins --output=json | jq .
[
  {
    "name": "test_plugin",
    "appbuilder_views": [
      {
        "name": "Test View",
        "category": "Test Plugin",
        "view": "<test_plugin.PluginTestAppBuilderBaseView object at 0x7fe21ed57860>"
      }
    ],
    "flask_blueprints": [
      "<flask.blueprints.Blueprint object at 0x7fe21ed57898>"
    ],
    "appbuilder_menu_items": [
      {
        "name": "Google",
        "href": "https://www.google.com",
        "category": "Search"
      },
      {
        "name": "apache",
        "href": "https://www.apache.org/",
        "label": "The Apache Software Foundation"
      }
    ],
    "executors": [
      "PluginExecutor"
    ],
    "hooks": [
      "PluginHook"
    ],
    "macros": [
      "<function plugin_macro at 0x7fe248a88400>"
    ],
    "operator_extra_links": [
      "GoogleLink()",
      "AirflowLink2()",
      "CustomOpLink()",
      "CustomBaseIndexOpLink(index=1)"
    ],
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "global_operator_extra_links": [
      "AirflowLink()",
      "GithubLink()"
    ]
  },
  {
    "name": "plugin-a",
    "appbuilder_views": [],
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "executors": [],
    "hooks": [],
    "macros": [],
    "operator_extra_links": [],
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "global_operator_extra_links": []
  },
  {
    "name": "plugin-b",
    "appbuilder_views": [],
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "executors": [],
    "hooks": [],
    "macros": [],
    "operator_extra_links": [],
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "global_operator_extra_links": []
  },
  {
    "name": "plugin-c",
    "appbuilder_views": [],
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "executors": [],
    "hooks": [],
    "macros": [],
    "operator_extra_links": [],
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "global_operator_extra_links": []
  },
  {
    "name": "postload",
    "appbuilder_views": [],
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "executors": [],
    "hooks": [],
    "macros": [],
    "operator_extra_links": [],
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "global_operator_extra_links": []
  }
]

After:

$ AIRFLOW__CORE__PLUGINS_FOLDER=$PWD/tests/plugins airflow plugins --output=json | jq .
[
  {
    "name": "test_plugin",
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "flask_blueprints": [
      "<flask.blueprints.Blueprint: name='test_plugin' import_name='test_plugin'>"
    ],
    "appbuilder_menu_items": [
      {
        "name": "Google",
        "href": "https://www.google.com",
        "category": "Search"
      },
      {
        "name": "apache",
        "href": "https://www.apache.org/",
        "label": "The Apache Software Foundation"
      }
    ],
    "operator_extra_links": [
      "<tests.test_utils.mock_operators.GoogleLink>",
      "<tests.test_utils.mock_operators.AirflowLink2>",
      "<tests.test_utils.mock_operators.CustomOpLink>",
      "<tests.test_utils.mock_operators.CustomBaseIndexOpLink>"
    ],
    "macros": [
      "test_plugin.plugin_macro"
    ],
    "hooks": [
      "test_plugin.PluginHook"
    ],
    "global_operator_extra_links": [
      "<tests.test_utils.mock_operators.AirflowLink>",
      "<tests.test_utils.mock_operators.GithubLink>"
    ],
    "appbuilder_views": [
      {
        "name": "Test View",
        "category": "Test Plugin",
        "view": "test_plugin.PluginTestAppBuilderBaseView"
      }
    ],
    "executors": [
      "test_plugin.PluginExecutor"
    ],
    "timetables": [
      "test_plugin.CustomCronDataIntervalTimetable"
    ]
  },
  {
    "name": "plugin-a",
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "operator_extra_links": [],
    "macros": [],
    "hooks": [],
    "global_operator_extra_links": [],
    "appbuilder_views": [],
    "executors": [],
    "timetables": []
  },
  {
    "name": "plugin-b",
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "operator_extra_links": [],
    "macros": [],
    "hooks": [],
    "global_operator_extra_links": [],
    "appbuilder_views": [],
    "executors": [],
    "timetables": []
  },
  {
    "name": "plugin-c",
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "operator_extra_links": [],
    "macros": [],
    "hooks": [],
    "global_operator_extra_links": [],
    "appbuilder_views": [],
    "executors": [],
    "timetables": []
  },
  {
    "name": "postload",
    "source": "$PLUGINS_FOLDER/test_plugin.py",
    "flask_blueprints": [],
    "appbuilder_menu_items": [],
    "operator_extra_links": [],
    "macros": [],
    "hooks": [],
    "global_operator_extra_links": [],
    "appbuilder_views": [],
    "executors": [],
    "timetables": []
  }
]

---

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[uranusjr]

Very nice! What's significant about the angle brackets?

[mik-laj]

@uranusjr This is an object, not a class. I tried to follow the official Python convention: https://docs.python.org/3/reference/datamodel.html?highlight=__repr__#object.__repr__ .

[uranusjr]

Ah OK, thanks for the explaination. Maybe it'd be clearer to say something like

<tests.test_utils.mock_operators.GithubLink object>

instead? This would be closer to the built-in repr format as well

>>> class Foo:
...  pass
...
>>> Foo()
<__main__.Foo object at 0x7f2dc444efa0>

[mik-laj]

@uranusjr Done

[github-actions]

The PR most likely needs to run full matrix of tests because it modifies parts of the core of Airflow. However, committers might decide to merge it quickly and take the risk. If they don't merge it quickly - please rebase it to the latest main at your convenience, or amend the last commit of the PR, and push it with --force-with-lease.