[AIRFLOW-5710] Optionally raise exception on unused operator arguments.

[jmcarp]

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Jira

• My PR addresses the following Airflow Jira issues and references them in the PR title. For example, "[AIRFLOW-XXX] My Airflow PR"
  • https://issues.apache.org/jira/browse/AIRFLOW-5710
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Description

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My team doesn't always notice warnings for unused operator arguments, and the behavior in airflow 2.0 (raising an exception) would be useful to us. This patch adds an ALLOW_ILLEGAL_ARGUMENTS configuration option that defaults to True, and if False raises an exception on unused arguments.

Tests

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  4. Subject uses the imperative mood ("add", not "adding")
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  6. Body explains "what" and "why", not "how"

Documentation

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[codecov-io]

Codecov Report

Merging #6332 into master will decrease coverage by 0.19%.
The diff coverage is n/a.

@@            Coverage Diff            @@
##           master    #6332     +/-   ##
=========================================
- Coverage   80.31%   80.12%   -0.2%     
=========================================
  Files         616      616             
  Lines       35812    35814      +2     
=========================================
- Hits        28763    28696     -67     
- Misses       7049     7118     +69

Impacted Files	Coverage Δ
airflow/models/baseoperator.py	95.65% <ø> (+0.02%)	⬆️
airflow/kubernetes/volume_mount.py	44.44% <0%> (-55.56%)	⬇️
airflow/kubernetes/volume.py	52.94% <0%> (-47.06%)	⬇️
airflow/kubernetes/pod_launcher.py	45.25% <0%> (-46.72%)	⬇️
airflow/kubernetes/kube_client.py	33.33% <0%> (-41.67%)	⬇️
...rflow/contrib/operators/kubernetes_pod_operator.py	70.14% <0%> (-28.36%)	⬇️
airflow/jobs/scheduler_job.py	74.43% <0%> (+1.2%)	⬆️
airflow/utils/dag_processing.py	58.56% <0%> (+1.99%)	⬆️
airflow/executors/__init__.py	67.34% <0%> (+4.08%)	⬆️
... and 3 more

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[mik-laj]

Can you create a ticket and add a short note in the documentation? The ticket will allow us to easier manage relaase, and the documentation will allow other people to use this feature.

[OmerJog]

Shouldn't be here a short note explaining what this setting does?
Something like
# When set to False raise exception on unused operator arguments

[mik-laj]

I added in the separate PR.
#6435

[jeesim2]

@OmerJog I am new to airflow and confused with allow_illegal_arguments option.
With airflow version 1.10.0 I can't not pass arguments to DAGS by conf.
The default airflow.cfg event don't have allow_illegal_arguments property.

At master branch, there allow_illegal_arguments option exists again.
My understanding is trigger a dag with custom conf is completely impossible from 1.10.0.

So, How can I trigger a DAG with some arguments?
Giving job parameters when trigger a job is very common when using Jenkins.
Is there any alternatives?