Repository: grpc/grpc-go
File: examples/features/opentelemetry/client/main.go (Go)

Code before:
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

// Binary client is a client for the OpenTelemetry example.
package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net/http"
	"time"

	"github.com/prometheus/client_golang/prometheus/promhttp"
	"go.opentelemetry.io/otel/exporters/prometheus"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/sdk/metric"
	"go.opentelemetry.io/otel/sdk/trace"
	"go.opentelemetry.io/otel/sdk/trace/tracetest"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
	"google.golang.org/grpc/examples/features/proto/echo"
	experimental "google.golang.org/grpc/experimental/opentelemetry"
	"google.golang.org/grpc/stats/opentelemetry"
)

var (
	addr               = flag.String("addr", ":50051", "the server address to connect to")
	prometheusEndpoint = flag.String("prometheus_endpoint", ":9465", "the Prometheus exporter endpoint")
)

func main() {
	exporter, err := prometheus.New()
	if err != nil {
		log.Fatalf("Failed to start prometheus exporter: %v", err)
	}
	provider := metric.NewMeterProvider(metric.WithReader(exporter))

	spanExporter := tracetest.NewInMemoryExporter()
	spanProcessor := trace.NewSimpleSpanProcessor(spanExporter)
	tracerProvider := trace.NewTracerProvider(trace.WithSpanProcessor(spanProcessor))
	textMapPropagator := propagation.NewCompositeTextMapPropagator(opentelemetry.GRPCTraceBinPropagator{})
	traceOptions := experimental.TraceOptions{
		TracerProvider:    tracerProvider,

Review comment (suggestion):
we shouldn't be using tracetest for example. Can you check other exporters that otel provides? For example, here in https://opentelemetry.io/docs/languages/go/getting-started/, they are using stdouttrace. We can use the same.

Code after:
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

// Binary client is a client for the OpenTelemetry example.
package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net/http"
	"time"

	"github.com/prometheus/client_golang/prometheus/promhttp"
	"go.opentelemetry.io/otel/exporters/prometheus"
	otelstdouttrace "go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
	otelpropagation "go.opentelemetry.io/otel/propagation"
	otelmetric "go.opentelemetry.io/otel/sdk/metric"
	otelresource "go.opentelemetry.io/otel/sdk/resource"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	semconv "go.opentelemetry.io/otel/semconv/v1.24.0"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
	"google.golang.org/grpc/examples/features/proto/echo"
	oteltracing "google.golang.org/grpc/experimental/opentelemetry"
	"google.golang.org/grpc/stats/opentelemetry"
)

var (
	addr               = flag.String("addr", ":50051", "the server address to connect to")
	prometheusEndpoint = flag.String("prometheus_endpoint", ":9465", "the Prometheus exporter endpoint for metrics")
)

func main() {
	exporter, err := prometheus.New()
	if err != nil {
		log.Fatalf("Failed to start prometheus exporter: %v", err)
	}
	// Configure meter provider for metrics
	meterProvider := otelmetric.NewMeterProvider(otelmetric.WithReader(exporter))
	// Configure exporter for traces
	traceExporter, err := otelstdouttrace.New(otelstdouttrace.WithPrettyPrint())
	if err != nil {
		log.Fatalf("Failed to create stdouttrace exporter: %v", err)