feat: When using streaming_generator return final pipeline result as a final streaming chunk

[sjrl]

Related Issues

• fixes Extend streaming_generator to also return the Pipeline result #146

Changes

• Adds a on_pipeline_end callback to streaming_generator and async_streaming_generator. This callback is called on the final result returned to the pipeline allowing us to forward the final result of the pipeline to OpenWebUI via a StreamingChunk
• Adds the function default_on_pipeline_end to serve as a default callback users can provide to streaming_generator and async_streaming_generator

Example

I added the function

    def on_pipeline_end(self, result: dict) -> str:
        documents = result.get("documents", [])
        references_str = f"\n\n### All Sources:\n"
        if documents:
            for idx, doc in enumerate(documents):
                references_str += f"- [{idx + 1}] {doc.meta['url']}\n"
        return references_str

to add a references section after the chat with website agent was finished

Screen.Recording.2025-10-10.at.10.44.59.mov

[mpangrazzi]

@sjrl I like the idea of the on_pipeline_end callback!

I've left some comments.

About tests: since now the on_pipeline_end callback is optional (which is good IMHO), why changing all the existing tests? Maybe we could revert this and add some specific tests with specific behaviours of that callback. WDYT?

[sjrl]

@sjrl I like the idea of the on_pipeline_end callback!

I've left some comments.

About tests: since now the on_pipeline_end callback is optional (which is good IMHO), why changing all the existing tests? Maybe we could revert this and add some specific tests with specific behaviours of that callback. WDYT?

Sure happy to revert!

[mpangrazzi]

Nice! 🚀

Would also ask if you can update the docs page about Open WebUI integration adding also info about this new callback. Would be great if you can also add the video (in gif) format into assets folder, showing it just after an example.

You can check out the docs contributing guide to run docs website locally (for development) and then deploy it!

[mpangrazzi]

🙌