Questions about Tracing Sub-segments in Private API Using Lambda PowerTools

[jaeyoung0509]

Firstly, I've been effectively using Lambda PowerTools for my serverless development.
In my setup, I have a Lambda service that acts as an API Gateway Public API, and beyond that, there's a Private API Lambda which carries out the actual logic.
I aim to trace the request flow as:
request -> public API Lambda(*root segement)-> private API Lambda(*sub segment) -> aws service

I've perused the documentation and noted that using powertools.trace automatically generates a trace header. I can forward this header to the private API Lambda. However, I'm uncertain about how to register a sub-segment for this private API Lambda.

[leandrodamascena]

Hello @jaeyoung0509! Firstly, sorry for the late response, we normally respond in less than 1 day but this was an unusual week where we missed some responses on time.

Let me see if I understand your user case:
In the internet-facing API with Lambda you have the root segment with lambda_handler and then you invoke a Private API with Lambda and want to create only a subsegment and not a root segment? I'm sorry, but I don't think I'm understanding the whole picture here.

Do you think you can draw a flow diagram or send some snippets/screenshots? This would make my understanding easier.

Thank you so much and I will put this discussion in my priorities.