Cloud Trace gRPC demo

A simple gRPC server using the helloworld example to demonstrate instrumenting a grpc server with Open Telemetry and Google Cloud Trace.

The SayHello will automatically fail with an internal grpc error to demonstrate the status handling in Cloud Trace.

Prerequisites:

• A GCP project with tracing enabled
• A GCP user logged in, with the correct IAM permission to create/view traces

To run it:

1. PROJECT_ID=<gcp_project_id> go run *.go
2. See that the call errored with this log message could not greet: rpc error: code = Internal desc = force error
3. Go to the Cloud Trace dashboard and observe that span appears normal, it's not coloured red.