Observability

Every call goes through, from the outermost:

1. the otelgrpc instrumentation,
2. the call log,
3. the panic recovery,
4. the registered interceptors and the service.

Traces

Each call gets a server span:

• named after the full method: users.v1.Users/GetUser,
• with the RPC semantic conventions attributes: rpc.system.name, rpc.method and rpc.response.status_code,
• with an error status for server errors: Unknown, DeadlineExceeded, Unimplemented, Internal, Unavailable and DataLoss.

The incoming trace context is extracted from the call metadata with the application propagator, so the span continues the trace of the caller. Spans created in services with the call context are children of the call span.

Metrics

Metric	Description
rpc.server.call.duration	Duration of the calls, with the rpc.method and rpc.response.status_code attributes

Logs

Each call is logged as grpc request, at error level for server errors (see above) and info level otherwise, with:

Attribute	Example
rpc	/users.v1.Users/GetUser
service	users.v1.Users
method	GetUser
code	NotFound
error	user not found, the error message, if any
duration	1.2ms

The log is correlated with the call span. Disable call logs with grpcserver.log.enabled: false.

Panics

A panic in a service or an interceptor is logged as grpc handler panic at error level, with the rpc, panic and stack attributes, and answered with an Internal error. The span and the call log record the Internal code.

Exclude methods

The health checks and the server reflection are excluded from spans, metrics and call logs by default. To exclude other methods, list their full methods; the list replaces the default one:

grpcserver:
  observability:
    exclude:
      - /grpc.health.v1.Health/Check
      - /grpc.health.v1.Health/Watch
      - /grpc.health.v1.Health/List
      - /grpc.reflection.v1.ServerReflection/ServerReflectionInfo
      - /grpc.reflection.v1alpha.ServerReflection/ServerReflectionInfo
      - /users.v1.Users/Ping