[AIRFLOW-4222] Add cli autocomplete for bash & zsh

[kaxil]

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  • https://issues.apache.org/jira/browse/AIRFLOW-4222

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Code Quality

• Passes flake8

[ashb]

Is it possible to have this as airflow autocompletions or something (which just tries to import that module etc.)

[kaxil]

Not sure as it would have to find out current Shell (bash/zsh - which might be easy) and then export that command to .bash_rc or .bash_profile or .zshrc etc by running some bash commands?

[ashb]

Just the register-python-argcomplete airflow bit - not the eval etc.

So this line would be

Suggested change

	eval "$(register-python-argcomplete airflow)"
	eval "$(airflow autocompletions)"

[kaxil]

Aah ok. That should be plausible. Let me give it a go

[kaxil]

Well this isn't as trivial as I thought it would because just running airflow prints out the following:

/Users/kaxilnaik/Documents/GitHub/incubator-airflow/airflow/models/dagbag.py:21: DeprecationWarning: the imp module is deprecated in favour of importlib; see the module's documentation for alternative uses
  import imp
[2019-08-13 22:30:04,803] {settings.py:173} INFO - settings.configure_orm(): Using pool settings. pool_size=5, max_overflow=10, pool_recycle=1800, pid=86597
/Users/kaxilnaik/.virtualenvs/airflow_cli_test/lib/python3.7/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
[2019-08-13 22:30:04,876] {__init__.py:51} INFO - Using executor LocalExecutor

Example implementation:

If we then run eval $(airflow autocomplete) it gives the following error:

/Users/kaxilnaik/Documents/GitHub/incubator-airflow/airflow/models/dagbag.py:21: DeprecationWarning: the imp module is deprecated in favour of importlib; see the module's documentation for alternative uses
  import imp
/Users/kaxilnaik/.virtualenvs/airflow_cli_test/lib/python3.7/site-packages/psycopg2/__init__.py:144: UserWarning: The psycopg2 wheel package will be renamed from release 2.8; in order to keep installing from binary please use "pip install psycopg2-binary" instead. For details see: <http://initd.org/psycopg/docs/install.html#binary-install-from-pypi>.
  """)
zsh: bad pattern: [2019-08-13

as it is trying to parse the log line [2019-08-13 22:29:39,045] {settings.py:173} INFO - settings.configure_orm(): Using pool settings. pool_size=5, max_overflow=10, pool_recycle=1800, pid=86465

Hence, not implementing this as part of this PR. Let's revisit this later.

[ashb]

Oh that damn logging whenever we import airflow :(

[mik-laj]

What do you think to add DAG/Task name suggestion? I think this library supports it.

[kaxil]

@mik-laj It would have to access the DB to get task name and Dag Name.

Let's merge this one so we get a basic auto-completer. And then we can add functionalities to it.

Some of the things I will add this week would be around filename completions

[mik-laj]

Docs errors:

/opt/airflow/docs/howto/cli-completion.rst:43: WARNING: image file not readable: howto/img/cli_completion.gif