[productcatalogservice]add basic metric support

CHANGELOG.md

@@ -176,3 +176,5 @@ significant modifications will be credited to OpenTelemetry Authors.
 ([#663](https://github.com/open-telemetry/opentelemetry-demo/pull/663))
 * Add `OTEL_RESOURCE_ATTRIBUTES` to docker compose setup
 ([#664](https://github.com/open-telemetry/opentelemetry-demo/pull/664))
+* Add basic metric support to productcatalog service
+([#674](https://github.com/open-telemetry/opentelemetry-demo/pull/674))

docker-compose.yml

@@ -421,6 +421,8 @@ services:
       - PRODUCT_CATALOG_SERVICE_PORT
       - FEATURE_FLAG_GRPC_SERVICE_ADDR
       - OTEL_EXPORTER_OTLP_TRACES_ENDPOINT
+      - OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
+      - OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE
       - OTEL_RESOURCE_ATTRIBUTES
       - OTEL_SERVICE_NAME=productcatalogservice
     depends_on:

docs/metric_service_features.md

@@ -7,7 +7,7 @@ Emoji Legend
 - Not Present (Yet): :construction:
 
 | Service         | Language        | Auto Instrumentation | Manual Metric Creation | Collector Agent Metric Transformation | Push Metrics   | SLO Metrics    | Multiple Manual Metric Instruments |
-|-----------------|-----------------|----------------------|------------------------|---------------------------------------|----------------|----------------|------------------------------------|
+| --------------- | --------------- | -------------------- | ---------------------- | ------------------------------------- | -------------- | -------------- | ---------------------------------- |
 | Ad              | Java            | :100:                | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
 | Cart            | .NET            | :100:                | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
 | Checkout        | Go              | :100:                | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
@@ -16,6 +16,6 @@ Emoji Legend
 | Feature Flag    | Erlang / Elixir | :construction:       | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
 | Frontend        | JavaScript      | :construction:       | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
 | Payment         | JavaScript      | :construction:       | :100:                  | :construction:                        | :construction: | :construction: | :construction:                     |
-| Product Catalog | Go              | :construction:       | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
-| Recommendation  | Python          | :100:       | :100:                  | :construction:                        | :construction: | :construction: | :construction:                     |
+| Product Catalog | Go              | :100:                | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |
+| Recommendation  | Python          | :100:                | :100:                  | :construction:                        | :construction: | :construction: | :construction:                     |
 | Shipping        | Rust            | :construction:       | :construction:         | :construction:                        | :construction: | :construction: | :construction:                     |

docs/services/productcatalogservice.md

@@ -54,7 +54,7 @@ as part of the gRPC server creation.
 ```
 
 This service will issue outgoing gRPC calls, which are all instrumented by
-wrapping the gRPC client with instrumentation
+wrapping the gRPC client with instrumentation.
 
 ```go
 func createClient(ctx context.Context, svcAddr string) (*grpc.ClientConn, error) {
@@ -108,7 +108,49 @@ or when a product is successfully found.
 
 ## Metrics
 
-TBD
+### Initializing Metrics
+
+The OpenTelemetry SDK is initialized from `main` using the `initMeterProvider`
+function.
+
+```go
+func initMeterProvider() *sdkmetric.MeterProvider {
+    ctx := context.Background()
+
+    exporter, err := otlpmetricgrpc.New(ctx)
+    if err != nil {
+        log.Fatalf("new otlp metric grpc exporter failed: %v", err)
+    }
+
+    mp := sdkmetric.NewMeterProvider(sdkmetric.WithReader(sdkmetric.NewPeriodicReader(exporter)))
+    global.SetMeterProvider(mp)
+    return mp
+}
+```
+
+You should call `initMeterProvider.Shutdown()` when your service is shutdown to
+ensure all records are exported. This service makes that call as part of a
+deferred function in main.
+
+```go
+    mp := initMeterProvider()
+    defer func() {
+        if err := mp.Shutdown(context.Background()); err != nil {
+            log.Fatalf("Error shutting down meter provider: %v", err)
+        }
+    }()
+```
+
+### Adding golang runtime auto-instrumentation
+
+Golang runtime is instrumented in the main function
+
+```go
+    err := runtime.Start(runtime.WithMinimumReadMemStatsInterval(time.Second))
+    if err != nil {
+        log.Fatal(err)
+    }
+```
 
 ## Logs
 

src/productcatalogservice/go.mod

@@ -4,33 +4,37 @@ go 1.17
 
 require (
 	github.com/golang/protobuf v1.5.2 // indirect
-	github.com/google/go-cmp v0.5.7
 	github.com/sirupsen/logrus v1.8.1
-	golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd // indirect
-	google.golang.org/grpc v1.44.0
+	golang.org/x/net v0.0.0-20220722155237-a158d28d115b // indirect
+	google.golang.org/grpc v1.51.0
 )
 
 require (
-	go.opentelemetry.io/otel/sdk v1.4.1
-	google.golang.org/protobuf v1.27.1
+	go.opentelemetry.io/contrib/instrumentation/runtime v0.37.0
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v0.34.0
+	go.opentelemetry.io/otel/metric v0.34.0
+	go.opentelemetry.io/otel/sdk v1.11.2
+	go.opentelemetry.io/otel/sdk/metric v0.34.0
+	go.opentelemetry.io/otel/trace v1.11.2
+	google.golang.org/protobuf v1.28.1
 )
 
 require (
-	github.com/cenkalti/backoff/v4 v4.1.2 // indirect
-	github.com/go-logr/logr v1.2.2 // indirect
+	github.com/cenkalti/backoff/v4 v4.2.0 // indirect
+	github.com/go-logr/logr v1.2.3 // indirect
 	github.com/go-logr/stdr v1.2.2 // indirect
-	github.com/grpc-ecosystem/grpc-gateway v1.16.0 // indirect
-	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.4.1 // indirect
-	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.4.1 // indirect
-	go.opentelemetry.io/otel/trace v1.4.1 // indirect
-	go.opentelemetry.io/proto/otlp v0.12.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.7.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.11.2 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric v0.34.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.11.2 // indirect
+	go.opentelemetry.io/proto/otlp v0.19.0 // indirect
 )
 
 require (
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.29.0
-	go.opentelemetry.io/otel v1.4.1
+	go.opentelemetry.io/otel v1.11.2
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.4.1
-	golang.org/x/sys v0.0.0-20220114195835-da31bd327af9 // indirect
-	golang.org/x/text v0.3.7 // indirect
+	golang.org/x/sys v0.0.0-20220919091848-fb04ddd9f9c8 // indirect
+	golang.org/x/text v0.4.0 // indirect
 	google.golang.org/genproto v0.0.0-20220126215142-9970aeb2e350 // indirect
 )