Feature: Handle Bedrock redactedContent

[afarntrog]

Description

This pull request introduces support for handling redactedContent in the event streaming pipeline, ensuring that redacted reasoning content is properly processed and tested throughout the codebase. The changes include updates to event handling logic, the addition of a new event type, and comprehensive unit and integration tests to verify correct behavior.

Event streaming enhancements:

• Added a new RedactedContentStreamEvent class to represent streaming events containing redacted reasoning content in src/strands/types/_events.py.
• Updated the handle_content_block_delta and handle_content_block_stop functions in src/strands/event_loop/streaming.py

Testing improvements:

• Added and extended unit tests in tests/strands/event_loop/test_streaming.py to cover scenarios involving redactedContent, including state updates and event emission for both new and existing redacted content.
• Enhanced async test coverage for process_stream, including cases with redacted content

Integration test updates:

• Added an integration test in tests_integ/models/test_model_bedrock.py to verify correct handling of redacted reasoning content when using the Bedrock model with thinking mode enabled.

Related Issues

#99
Source pr: #229

Documentation PR

strands-agents/docs#90

Type of Change

New feature

Testing

How have you tested the change? Verify that the changes do not break functionality or introduce warnings in consuming repositories: agents-docs, agents-tools, agents-cli

• I ran hatch run prepare

Checklist

• I have read the CONTRIBUTING document
• I have added any necessary tests that prove my fix is effective or my feature works
• I have updated the documentation accordingly
• I have added an appropriate example to the documentation to outline the feature, or no new docs are needed
• My changes generate no new warnings
• Any dependent changes have been merged and published

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[dbschmigelski]

OK OK OK OK

Now I understand why this is safe and before it was not for signature.

So, for signature we are checking if "signature" in state: so even when signature was empty it was getting added to the content block

Now we are seeing if redacted_content is truthy, meaning setting it to b"" is fine.

I think we can use this to rethink our signature fix but I'm fine with keeping as is.

Unrelated, do you know if the Bedrock docs are wrong? It seems the redactedContent is coming back as bytes but the docs state it is Base64-encoded? Are we decoding somewhere or is a client doing it under the good?

[dbschmigelski]

Approved in spirit, pretty sure you need to rebase

[afarntrog]

....
Unrelated, do you know if the Bedrock docs are wrong? It seems the redactedContent is coming back as bytes but the docs state it is Base64-encoded? Are we decoding somewhere or is a client doing it under the good?

So I confirmed it's coming in as bytes in the actual response; the encoding is coming from the client. The docs state:

Type: Base64-encoded binary data object

which can possibly cause confusion but seems to imply it's coming in as bytes 👍

[dbschmigelski]

One nit comment

other than that just one minor nit that when you merge can you just remember to follow https://www.conventionalcommits.org/en/v1.0.0/