Observability

Every call goes through, from the outermost:

1. the otelgrpc instrumentation,
2. the call log,
3. the registered interceptors.

Traces

Each call gets a client 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 span is a child of the span of the call context. The trace context is injected in the call metadata with the application propagator, so the server span, of a grpcserver application for example, continues the trace.

Metrics

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

Logs

Each call is logged as grpc client 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
target	users:50051, the connection target
code	NotFound
error	user not found, the error message, if any
duration	1.2ms

Streaming calls are logged once the stream is created, with the code of its creation. The log is correlated with the call span. Disable call logs with grpcclient.log.enabled: false.

Exclude methods

To exclude methods from spans, metrics and call logs, list their full methods:

grpcclient:
  observability:
    exclude:
      - /grpc.health.v1.Health/Check
      - /users.v1.Users/Ping