feature/actions: WIP

.github/workflows/tracing.yml

@@ -0,0 +1,24 @@
+name: Enable Tracing for PR
+
+on:
+  pull_request:
+    types: [opened, synchronize, labeled, unlabeled, closed]
+
+jobs:
+  tracing:
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v2
+
+    - name: Check for "enable tracing" label
+      id: check-label
+      run: |
+        label=$(jq -r '.pull_request.labels[].name' "$GITHUB_EVENT_PATH")
+        if [[ "$label" == "enable tracing" ]]; then
+          echo "Enable tracing label found."
+          echo "::set-output name=trace::true"
+        else
+          echo "Enable tracing label not found."
+          echo "::set-output name=trace::false"
+        fi

internal/examples/example-grpc-client-server/server/server_main.go

@@ -38,7 +38,7 @@ func main() {
 	telemetryTarget := os.Getenv("TELEMETRY_TARGET")
 
 	opts := make([]server.ServerOption, 0, 1)
-	if enableTelemetry == "true" {
+	if enableTelemetry == "true" && telemetryTarget != "" {
 		opts = append(opts, server.WithOpenTelemetry(telemetryTarget))
 	}
 

internal/examples/example-otlp-agent-tempo-grafana/docker-compose.yaml

@@ -1,6 +1,7 @@
 version: "3"
 services:
 
+  # Instrumented application configured to export traces to ...
   example-grpc-server:
     build: 
       context: ../../../
@@ -13,7 +14,7 @@ services:
       - ENABLE_TELEMETRY=true
       - TELEMETRY_TARGET=otel-collector:4317
 
-  # Put traces in a Grafana Agent pipeline...
+  # ... the OpenTelemetry Collector configured to receive traces and export to Tempo ...
   otel-collector:
     image: otel/opentelemetry-collector:0.61.0
     command: [ "--config=/etc/otel-collector.yaml" ]
@@ -24,7 +25,7 @@ services:
     depends_on:
       - tempo
 
-  # To eventually offload to Tempo...
+  # .. Which accepts requests from grafana ...
   tempo:
     image: grafana/tempo:latest
     command: [ "-config.file=/etc/tempo.yaml" ]

server/server.go

@@ -121,8 +121,9 @@ func (s *Server) Serve() {
 	s.grpcServer = grpc.NewServer(
 		grpc.UnaryInterceptor(
 			grpc_middleware.ChainUnaryServer(
-				otelgrpc.UnaryServerInterceptor(),
 				loggingUnaryServerInterceptor,
+				otelgrpc.UnaryServerInterceptor(),
+
 			),
 		),
 	)