Instrumenting server calls

Service-side instrumentation is similar. We can use the gRPC interceptor again and this time override the UnaryServerHandler method. Once the request is received, we should extract the context and start a new activity. It should have the server kind, a name that follows the same pattern as for the client span – {package.service}/{method} – and attributes very similar to those we saw on the client. Here’s the interceptor code:

server/GrpcTracingInterceptor.cs

var traceContext = _propagator.Extract(default,
  ctx.RequestHeaders,
  static (headers, k) => new[] { headers.GetValue(k) });
Baggage.Current = traceContext.Baggage;
using var activity = Source.StartActivity(ctx.Method,
  ActivityKind.Server, traceContext.ActivityContext);
if (activity?.IsAllDataRequested != true)
  return await continuation(request, ctx);
SetRpcAttributes(activity, ctx.Host, ctx.Method);
try
{
  var response...