sdks/python: enrich data with CloudSQL

[mohamedawnallah]

Description

• Add CloudSQLEnrichmentHandler
• Unit Test
• Integration Test
• Update Enrichment Docs

Closes #30773.

---

Thank you for your contribution! Follow this checklist to help us incorporate your contribution quickly and easily:

• Mention the appropriate issue in your description (for example: addresses #123), if applicable. This will automatically add a link to the pull request in the issue. If you would like the issue to automatically close on merging the pull request, comment fixes #<ISSUE NUMBER> instead.
• Update CHANGES.md with noteworthy changes.
• If this contribution is large, please file an Apache Individual Contributor License Agreement.

See the Contributor Guide for more tips on how to make review process smoother.

To check the build health, please visit https://github.com/apache/beam/blob/master/.test-infra/BUILD_STATUS.md

GitHub Actions Tests Status (on master branch)

See CI.md for more information about GitHub Actions CI or the workflows README to see a list of phrases to trigger workflows.

[mohamedawnallah]

Hi @claudevdm,

I think the PR is now ready for review. I’ve run all test cases locally, including the integration tests, and they pass since I’m using a PostgreSQL Cloud SQL managed instance in my Google Cloud for testing.

However, the integration tests currently fail in the CI pipeline because there’s no Cloud SQL testing instance to connect to. It seems like this may require additional setup or administration.

How am I supposed to move this PR forward?

Thanks!

[github-actions]

Checks are failing. Will not request review until checks are succeeding. If you'd like to override that behavior, comment assign set of reviewers

[mohamedawnallah]

assign set of reviewers

[github-actions]

Assigning reviewers. If you would like to opt out of this review, comment assign to next reviewer:

R: @liferoad for label python.
R: @damccorm for label website.

Available commands:

• stop reviewer notifications - opt out of the automated review tooling
• remind me after tests pass - tag the comment author after tests pass
• waiting on author - shift the attention set back to the author (any comment or push by the author will return the attention set to the reviewers)

The PR bot will only process comments in the main thread (not review comments).

[claudevdm]

Thank you for your contribution to the Cloud SQL Enrichment Handler. I'd like to share some thoughts about potential improvements:

• Query Flexibility: We should consider expanding the interface to allow users to:

  1. Select specific columns rather than always returning all columns
  2. Apply multiple filtering conditions (e.g., filtering on both customer_id AND region)
  3. Support more complex query conditions beyond simple equality checks

• SQLAlchemy Integration: Given that we're supporting three different database types (MySQL, PostgreSQL, and SQL Server), leveraging SQLAlchemy would:

  1. Provide database-agnostic query building
  2. Handle dialect-specific syntax differences automatically
  3. Offer better protection against SQL injection vulnerabilities

• Batch Processing Support: For performance optimization, we should implement batched queries similar to the BigQuery handler

  beam/sdks/python/apache_beam/transforms/enrichment_handlers/bigquery.py

  Line 180 in 6426f72

  def __call__(self, request: Union[beam.Row, list[beam.Row]], *args, **kwargs):

Could @liferoad and @svetakvsundhar share their thoughts on the user interface design and SQLAlchemy integration?