Feat: How to use Langfuse to trace Ragflow python-api

[KevinHuSh]

Discussed in https://github.com/orgs/infiniflow/discussions/6148

^{Originally posted by Sos-Zachary March 17, 2025} Hello, the maintainers, contributors and deep users of the project. I hope to use Langfuse to monitor and track the openai python api provided by Ragflow. I would like to trace the Q/A pairs and the retrieved documents of internal users, also the evaluations of users on the front end. I have implemented these functions through Langfuse when using a simple RAG-demo. I would like to ask how I can better track the above key points when using the Ragflow api? Especially, how can I record the retrieved documents based on the questions raised by users? Looking forward to your guide!