OpenTelemetry backend specification

[dwoznicki]

Hi folks, I'm thinking of implementing a backend that can receive OpenTelemetry data, and I have a few questions.

• Is there any documentation on implementing a backend?
• Is there a standard set of tests for making sure the backend handles input properly? I'm mainly worried about getting the model wrong for incoming data.
• What is the difference between raw OTLP data and data that has been run through a collector? Would it be at all useful to have my backend support both?

Thanks!