[Feature Request] OpenTelemetry Metrics OLTP/HTTP support

[slingshotvfx]

Is your feature request related to a problem? Please describe.

Right now the Python SDK (and possibly other Core SDKs?) only support OLTP over gRPC, but some services (like Pydantic Logfire) require OLTP over HTTPS

When trying to export metrics to these services today, I receive the following error:

OpenTelemetry metrics error occurred. Metrics exporter otlp failed with the grpc server returns error (Internal error): , detailed error message: protocol error: received message with invalid compression flag: 60 (valid flags are 0 and 1) while receiving response with status: 403 Forbidden

Describe the solution you'd like

Support for exporting OTel Metrics to services via OLTP/HTTP.

Additional context

This would bring the Python SDK up to parity with the Go SDK and possibly others which do support HTTP.

[cretz]

That is unfortunate that such a platform doesn't support such a common OTLP approach. This is implemented in our Rust Core layer, so I have opened an issue over there to support HTTP: temporalio/sdk-core#820. Once updated there we will apply here (may just be an http=True type of option on the OTel config).

[samuelcolvin]

Sorry temporal, we'll try to get grpc added as soon as possible.