Add OpenLIT to Haystack Integrations

[patcher9]

How OpenLIT works with Haystack?

OpenLIT basically wraps around OpenAI, Anthropic etc functions and configures OpenTelemetry tracing and metrics for it. In the Haystack pipelines whenever the user runs a pipeline(Since Haystack also uses the same LLM functions), We are automatically able to wrap the pipeline (without needing to create any additional instrumentation for Haystack).

We did add instrumentation just for Document loaders as the rest of the pipeline can directly be tracked for reasons mentioned above.

[patcher9]

@TuanaCelik , Tagging you for sanity as not sure who to tag for review on this :)

[TuanaCelik]

Thanks for the contribution @patcher9 - Sorry we're slow at getting to PRs on this repository. I'm assigning this to myself now and will test it and make a review 🙏

[bilgeyucel]

Hi @patcher9, is this still up-to-date? If so, I can review it as soon as possible!

[patcher9]

Hey @bilgeyucel It is very much up to date!