Add Dynamic Schema support to StorageWriteToBigQuery

[jrmccluskey]

Implements support for using dynamic schemas in StorageWriteToBigQuery invocations.

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[jrmccluskey]

/gemini review

[gemini-code-assist]

Code Review

This pull request adds support for dynamic schemas and schema side inputs when writing to BigQuery using the Storage Write API (StorageWriteToBigQuery). It includes updates to handle callable schemas, passes schema side inputs through the pipeline, adds validation to ensure dynamic schemas are only used with dynamic destinations, and provides comprehensive unit and integration tests. There are no review comments, and the implementation looks solid, so I have no additional feedback to provide.

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[gemini-code-assist]

Code Review

This pull request introduces support for dynamic schemas when writing to dynamic destinations using the BigQuery Storage Write API, including a new dynamic_schema helper function, updates to StorageWriteToBigQuery to handle dynamic schemas and side inputs, and comprehensive unit tests. The reviewer feedback highlights critical issues that need to be addressed: potential runtime NameError exceptions from referencing the bigquery module namespace within bigquery.py, unintended in-place mutation of user-provided schemas during merging, and potential serialization/encoding errors (CoderException) alongside performance overhead caused by dynamic beam.Row instantiation with None values.

Important

The consumer version of Gemini Code Assist on GitHub is being sunset. Starting June 18, 2026, new organization installations will be blocked, and all code review activity will officially cease on July 17, 2026.
For more details on the timeline and next steps, please review the Help Documentation.

[gemini-code-assist]

Caution

The consumer version of Gemini Code Assist on GitHub has been sunset. All code review activity has officially ceased.

[github-actions]

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R: @shunping for label python.

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