[AIRFLOW-3537] Add task_definition as templated parameter in AWS ECS Operator

[tomoyat]

Make sure you have checked all steps below.

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-3537
  • In case you are fixing a typo in the documentation you can prepend your commit with [AIRFLOW-XXX], code changes always need a Jira issue.

Description

• Here are some details about my PR, including screenshots of any UI changes:

When using the AWS ECS Operator, I'd like to pass the task_definition as a template. Because I decide the task_definition dynamically by another operator, and get the task_definition from XCom.

Tests

• My PR adds the following unit tests OR does not need testing for this extremely good reason:

Updated existing test case to check for new field.

Commits

• My commits all reference Jira issues in their subject lines, and I have squashed multiple commits if they address the same issue. In addition, my commits follow the guidelines from "How to write a good git commit message":
  1. Subject is separated from body by a blank line
  2. Subject is limited to 50 characters (not including Jira issue reference)
  3. Subject does not end with a period
  4. Subject uses the imperative mood ("add", not "adding")
  5. Body wraps at 72 characters
  6. Body explains "what" and "why", not "how"

Documentation

• In case of new functionality, my PR adds documentation that describes how to use it.
  • When adding new operators/hooks/sensors, the autoclass documentation generation needs to be added.
  • All the public functions and the classes in the PR contain docstrings that explain what it does

Code Quality

• Passes flake8

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[FridayPush]

Wish this had been merged. A pain point for us that's one field name added to a tuple.

[potiuk]

Wish this had been merged. A pain point for us that's one field name added to a tuple.

Feel free to contribute it as a PR. This is an open-source project with more than 2000 contributors - you are absolutely welcome to contribute such change @FridayPush

[FridayPush]

I appreciate the invitation @potiuk, generally this PR is what I would produce to make the change. I would likely have removed the template_fields test as it is a value check. Additionally the BaseOperator already has tests that validate the behavior of changes to the template_fields

Per the original PR review the only template rendering test I can find in other AWS Operators is the 'batch' operator.

If I was to submit a new PR with the changes to the template_fields how should tests be handled? Would you lean towards removing the test or adding the per field test referenced by mik-laj?

[potiuk]

Just add the field. It's enough.

[potiuk]

You take a look at other PRs people added with template fields. You will find a number of those If you search.