The endSpan closure accepted error by value, meaning deferred calls like
defer spanEnd(err) captured the error at defer-time (always nil), not at
function-return time. This meant errors were never recorded on spans.
- Changed endSpan to accept *error
- Updated all call sites in rpc/handler.go to pass error pointers, and
adjusted handleCall to avoid propagating child-span errors to the parent
- Added TestTracingHTTPErrorRecording to verify that errors from RPC
methods are properly recorded on the rpc.runMethod span
This PR adds support for the extraction of OpenTelemetry trace context
from incoming JSON-RPC request headers, allowing geth spans to be linked
to upstream traces when present.
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Co-authored-by: lightclient <lightclient@protonmail.com>
Add Open Telemetry tracing inside the RPC server to help attribute runtime costs within `handler.handleCall()`. In particular, it allows us to distinguish time spent decoding arguments, invoking methods via reflection, and actually executing the method and constructing/encoding JSON responses.
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Co-authored-by: lightclient <lightclient@protonmail.com>
