v4.1.0 — OpenTelemetry integration

OpenTelemetry integration

Trace individual JSON-RPC calls instead of seeing only an HTTP POST request. The new optional OpenTelemetryMiddleware creates a span for each call, including each item in a batch, and works alongside FastAPI's HTTP instrumentation.

• See which method was called and which JSON-RPC error it returned, even when the HTTP response is 200.
• Track call duration with the rpc.server.call.duration histogram, grouped by method, request type and error code.
• Distinguish calls, notifications and invalid requests in traces and metrics.
• Add application-specific span attributes with request and response hooks.
• Choose whether to record unhandled exceptions, with an option to redact them first. Request params and results are never recorded automatically; exception messages and stack traces are not recorded by default.

Install with pip install 'fastapi-jsonrpc[opentelemetry]' and add the middleware first in your entrypoint's middleware list. Configure the OpenTelemetry SDK and exporters in your application.

For notifications, spans and duration measurements cover validation and dispatch to the background scheduler, not the full background execution.

See the OpenTelemetry integration guide for setup, options and tracing boundaries.

Fixes

• Queued scheduler jobs now preserve the context of the request that created them, so request-local context and trace parentage are retained when a job waits for a free slot.

Dependencies

• Updated locked dependencies with security fixes and added the dependency needed by Starlette's current test client.

Thanks

Thank you @akalex for contributing the OpenTelemetry integration in #118!

Full changelog: v4.0.1...v4.1.0