Sara•10mo ago

Nested generations / spans in traces

Hi everyone! I'm trying to use the trace and observation IDs to create a nested set of observations instead of using the objects in the Python SDK. I was able to use langfuse.generation(CreateGeneration(traceId=trace.id)) instead of trace.generation(CreateGeneration()) to create a generation inside a trace but I'm having trouble creating observations under another observation. I tried the following which didn't work. I was expecting the following code to create, a span inside that trace, and a generation inside the span. But instead it creates a span and a generation inside the trace. Would appreciate some guidance on this.

langfuse = Langfuse(
  public_key=Config.fetch("langfuse-public-key"),
  secret_key=Config.fetch("langfuse-secret-key"),
  host=Config.fetch("langfuse-host")
)

trace = langfuse.trace(CreateTrace(
    user_id="test-user",
    metadata = {
        "env": "local",
    }
))
print("trace", trace.id)

span = langfuse.span(CreateSpan(
    traceId=trace.id,
    name="test-span",
    prompt="Hello world from span",
))
print("span", span.id)

generation = langfuse.generation(CreateGeneration(
    traceId=trace.id,
    parentObservationId=span.id,
    name="test-generation",
    prompt="Hello world from generation",
))
print("generation", generation.id)

langfuse = Langfuse(
  public_key=Config.fetch("langfuse-public-key"),
  secret_key=Config.fetch("langfuse-secret-key"),
  host=Config.fetch("langfuse-host")
)

trace = langfuse.trace(CreateTrace(
    user_id="test-user",
    metadata = {
        "env": "local",
    }
))
print("trace", trace.id)

span = langfuse.span(CreateSpan(
    traceId=trace.id,
    name="test-span",
    prompt="Hello world from span",
))
print("span", span.id)

generation = langfuse.generation(CreateGeneration(
    traceId=trace.id,
    parentObservationId=span.id,
    name="test-generation",
    prompt="Hello world from generation",
))
print("generation", generation.id)

2 Replies

Max•10mo ago

Hi Sara, great to have you here! Our pydantic interfaces are a bit confisung. You have to take InitialGeneration instead of CreateGeneration. We are working on this as we remove pydantic interfaces from the SDK (https://github.com/langfuse/langfuse-python/pull/215)

GitHub

feat(core): SDK Version 2 (#208) by maxdeichmann · Pull Request #21...

Sara•10mo ago

Oh I see! Thanks for the help Max! I'll give that a try