Utiliser des SDK pour envoyer des métriques depuis des applications

Ce document explique comment envoyer des métriques directement depuis des applications vers le point de terminaison OTLP à l'aide d'un SDK et de l'exportateur gRPC, qui est l'exportateur recommandé pour une utilisation avec les SDK. Le point de terminaison OTLP est compatible avec tous les protocoles OTLP, y compris http/proto, http/json et grpc. Pour en savoir plus, consultez la section Compatibilité avec le protocole.

Lorsque vous envoyez des métriques d'application directement au point de terminaison OTLP, le collecteur OpenTelemetry ne gère pas l'authentification ni l'enrichissement pour vous. Lorsque vous utilisez des SDK pour envoyer des métriques depuis des applications, vous devez procéder comme suit :

Avant de commencer

Pour exécuter les exemples, vous devez activer les API nécessaires et obtenir des identifiants d'authentification.

Activer les API

Activez les API Cloud Monitoring et Telemetry dans votre projetGoogle Cloud en exécutant la commande suivante :

gcloud services enable monitoring.googleapis.com telemetry.googleapis.com

Obtenir des identifiants d'authentification

Configurez les identifiants de l'exportateur gRPC OTLP pour qu'il utilise les identifiants par défaut de l'application Google en exécutant la commande suivante :

gcloud auth application-default login

Exemples spécifiques à une langue

Cette section propose une sélection d'exemples spécifiques à une langue qui créent et écrivent une métrique de compteur. Sélectionnez un onglet pour obtenir des informations sur l'exécution de l'exemple et pour afficher le code.

Go

Pour savoir comment configurer et exécuter cet exemple, consultez le fichier README de l'exemple Go.

// Copyright 2024 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// 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.

package main

import (
	"context"
	"errors"
	"log"

	"go.opentelemetry.io/contrib/detectors/gcp"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
	"go.opentelemetry.io/otel/metric"
	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
	"go.opentelemetry.io/otel/sdk/resource"
	semconv "go.opentelemetry.io/otel/semconv/v1.37.0"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/oauth"
)

func main() {
	ctx := context.Background()

	creds, err := oauth.NewApplicationDefault(ctx)
	if err != nil {
		panic(err)
	}

	res, err := resource.New(
		ctx,
		// Use the GCP resource detector to detect information about the GCP platform
		resource.WithDetectors(gcp.NewDetector()),
		// Keep the default detectors
		resource.WithTelemetrySDK(),
		// Add attributes from environment variables
		resource.WithFromEnv(),
		// Add your own custom attributes to identify your application
		resource.WithAttributes(
			semconv.ServiceNameKey.String("example-application"),
		),
	)
	if errors.Is(err, resource.ErrPartialResource) || errors.Is(err, resource.ErrSchemaURLConflict) {
		log.Println(err)
	} else if err != nil {
		panic(err)
	}

	// Set endpoint with OTEL_EXPORTER_OTLP_ENDPOINT or OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
	metricExporter, err := otlpmetricgrpc.New(ctx, otlpmetricgrpc.WithDialOption(grpc.WithPerRPCCredentials(creds)))
	if err != nil {
		panic(err)
	}

	meterProvider := sdkmetric.NewMeterProvider(
		sdkmetric.WithResource(res),
		sdkmetric.WithReader(sdkmetric.NewPeriodicReader(metricExporter)),
	)

	defer func() {
		if err = meterProvider.Shutdown(ctx); err != nil {
			log.Println(err)
		}
	}()

	meter := meterProvider.Meter("github.com/GoogleCloudPlatform/opentelemetry-operations-go/example/metric/otlpgrpc")

	// Register counter value
	counter, err := meter.Int64Counter("counter-a")
	if err != nil {
		log.Fatalf("Failed to create counter: %v", err)
	}
	clabels := []attribute.KeyValue{attribute.Key("key").String("value")}
	counter.Add(ctx, 100, metric.WithAttributes(clabels...))
}

Java

Pour savoir comment configurer et exécuter cet exemple, consultez le fichier README de l'exemple Java.

/*
 * Copyright 2025 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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.
 */
package com.google.cloud.opentelemetry.example.otlpmetric;

import com.google.auth.oauth2.GoogleCredentials;
import io.opentelemetry.api.metrics.LongCounter;
import io.opentelemetry.exporter.otlp.http.metrics.OtlpHttpMetricExporter;
import io.opentelemetry.exporter.otlp.metrics.OtlpGrpcMetricExporter;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.autoconfigure.AutoConfiguredOpenTelemetrySdk;
import io.opentelemetry.sdk.common.CompletableResultCode;
import io.opentelemetry.sdk.metrics.export.MetricExporter;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.concurrent.TimeUnit;

public class OTLPMetricExample {
  private static final String INSTRUMENTATION_SCOPE_NAME = OTLPMetricExample.class.getName();
  private static final Random RANDOM = new Random();

  private static OpenTelemetrySdk openTelemetrySdk;

  private static OpenTelemetrySdk setupMetricExporter() throws IOException {
    GoogleCredentials credentials = GoogleCredentials.getApplicationDefault();

    // Update the SDK configured using environment variables and system properties
    // TODO: Replace this with the use of gcp-auth-extension
    AutoConfiguredOpenTelemetrySdk autoConfOTelSdk =
        AutoConfiguredOpenTelemetrySdk.builder()
            .addMetricExporterCustomizer(
                (exporter, configProperties) -> addAuthorizationHeaders(exporter, credentials))
            .build();
    return autoConfOTelSdk.getOpenTelemetrySdk();
  }

  // Modifies the metric exporter initially auto-configured using environment variables
  // This will invoke the header supplier function to compute the headers, which takes care of the
  // refresh.
  private static MetricExporter addAuthorizationHeaders(
      MetricExporter exporter, GoogleCredentials credentials) {
    if (exporter instanceof OtlpHttpMetricExporter) {
      return ((OtlpHttpMetricExporter) exporter)
          .toBuilder().setHeaders(() -> getRequiredHeaderMap(credentials)).build();
    } else if (exporter instanceof OtlpGrpcMetricExporter) {
      return ((OtlpGrpcMetricExporter) exporter)
          .toBuilder().setHeaders(() -> getRequiredHeaderMap(credentials)).build();
    }
    return exporter;
  }

  private static Map<String, String> getRequiredHeaderMap(GoogleCredentials credentials) {
    Map<String, String> gcpHeaders = new HashMap<>();
    try {
      credentials.refreshIfExpired();
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
    gcpHeaders.put("Authorization", "Bearer " + credentials.getAccessToken().getTokenValue());
    String configuredQuotaProjectId = credentials.getQuotaProjectId();
    if (configuredQuotaProjectId != null && !configuredQuotaProjectId.isEmpty()) {
      gcpHeaders.put("x-goog-user-project", configuredQuotaProjectId);
    }
    return gcpHeaders;
  }

  private static void myUseCase() {
    LongCounter counter =
        openTelemetrySdk
            .getMeter(INSTRUMENTATION_SCOPE_NAME)
            .counterBuilder("example_counter")
            .setDescription("Processed jobs")
            .setUnit("1")
            .build();
    doWork(counter);
  }

  private static void doWork(LongCounter counter) {
    try {
      for (int i = 0; i < 10; i++) {
        counter.add(RANDOM.nextInt(100));
        Thread.sleep(RANDOM.nextInt(1000));
      }
    } catch (InterruptedException e) {
      throw new RuntimeException(e);
    }
  }

  public static void main(String[] args) throws IOException {
    // Configure the OpenTelemetry pipeline with CloudMetric exporter
    openTelemetrySdk = setupMetricExporter();

    // Application-specific logic
    myUseCase();

    // Flush all buffered metrics
    CompletableResultCode completableResultCode = openTelemetrySdk.getSdkMeterProvider().shutdown();
    // wait till export finishes
    completableResultCode.join(10000, TimeUnit.MILLISECONDS);
  }
}

NodeJS

Pour savoir comment configurer et exécuter cet exemple, consultez le fichier README de l'exemple NodeJS.

// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      https://www.apache.org/licenses/LICENSE-2.0
//
// 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.

import * as opentelemetry from '@opentelemetry/sdk-node';
import {AuthClient, GoogleAuth} from 'google-auth-library';
import {credentials} from '@grpc/grpc-js';
import {getResourceDetectors as getResourceDetectorsFromEnv} from '@opentelemetry/auto-instrumentations-node';
import {metrics, diag, DiagConsoleLogger} from '@opentelemetry/api';
import {OTLPMetricExporter} from '@opentelemetry/exporter-metrics-otlp-grpc';
import {PeriodicExportingMetricReader} from '@opentelemetry/sdk-metrics';

async function getAuthenticatedClient(): Promise<AuthClient> {
  const auth: GoogleAuth = new GoogleAuth({
    scopes: 'https://www.googleapis.com/auth/cloud-platform',
  });
  return await auth.getClient();
}

diag.setLogger(
  new DiagConsoleLogger(),
  opentelemetry.core.diagLogLevelFromString(
    opentelemetry.core.getStringFromEnv('OTEL_LOG_LEVEL'),
  ),
);

// App that exports metrics via gRPC with protobuf
async function main() {
  const authenticatedClient: AuthClient = await getAuthenticatedClient();

  const sdk = new opentelemetry.NodeSDK({
    metricReader: new PeriodicExportingMetricReader({
      // Export metrics every 10 seconds. 5 seconds is the smallest sample period allowed by
      // Cloud Monitoring.
      exportIntervalMillis: 10_000,
      exporter: new OTLPMetricExporter({
        credentials: credentials.combineChannelCredentials(
          credentials.createSsl(),
          credentials.createFromGoogleCredential(authenticatedClient),
        ),
      }),
    }),
    resourceDetectors: getResourceDetectorsFromEnv(),
  });
  sdk.start();

  // Create a meter
  const meter = metrics.getMeter('metrics-sample');

  // Create a counter instrument
  const counter = meter.createCounter('metric_name');
  // Record a measurement
  counter.add(10, {key: 'value'});

  // Wait for the metric to be exported
  await new Promise(resolve => {
    setTimeout(resolve, 11_000);
  });

  // Gracefully shut down the SDK to flush telemetry when the program exits
  process.on('SIGTERM', () => {
    sdk
      .shutdown()
      .then(() => diag.debug('OpenTelemetry SDK terminated'))
      .catch(error => diag.error('Error terminating OpenTelemetry SDK', error));
  });
}

main().catch(console.error);

Python

Pour savoir comment exécuter cet exemple, consultez le fichier README du fichier README de l'exemple Python.

#!/usr/bin/env python3
# Copyright 2025 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# 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.

import time

import google.auth
import google.auth.transport.grpc
import google.auth.transport.requests
import grpc
from google.auth.transport.grpc import AuthMetadataPlugin
from opentelemetry.exporter.otlp.proto.grpc.metric_exporter import (
    OTLPMetricExporter,
)
from opentelemetry.resourcedetector.gcp_resource_detector import GoogleCloudResourceDetector
from opentelemetry.sdk.resources import get_aggregated_resources
from opentelemetry.sdk.metrics import MeterProvider
from opentelemetry.sdk.metrics.export import PeriodicExportingMetricReader

"""
This is a sample script that exports OTLP metrics encoded as protobufs via gRPC. 
"""

credentials, project_id = google.auth.default()
request = google.auth.transport.requests.Request()
resource = get_aggregated_resources(
    [GoogleCloudResourceDetector(raise_on_error=True)]
)

auth_metadata_plugin = AuthMetadataPlugin(
    credentials=credentials, request=request
)
channel_creds = grpc.composite_channel_credentials(
    grpc.ssl_channel_credentials(),
    grpc.metadata_call_credentials(auth_metadata_plugin),
)

exporter = OTLPMetricExporter(credentials=channel_creds)
reader = PeriodicExportingMetricReader(exporter)
provider = MeterProvider(metric_readers=[reader],resource=resource)
meter = provider.get_meter("gcp.otlp.sample")
counter = meter.create_counter("sample.otlp.counter")


def do_work():
    counter.add(1)
    # do some work that the 'counter' will track
    print("doing some work...")


def do_work_repeatedly():
    try:
        while True:
            do_work()
            time.sleep(1)
    except KeyboardInterrupt:
        print("\nKeyboard Interrupt: Stopping work.")


do_work_repeatedly()

Utiliser l'API Downward pour les applications exécutées en tant que pods

Si vous exécutez l'application en tant que pod dans Kubernetes et que vous ne l'envoyez pas via l'OpenTelemetry Collector, veillez à utiliser l'API Downward pour définir les attributs de ressources Kubernetes :

env:
- name: POD_NAME
  valueFrom:
    fieldRef:
      fieldPath: metadata.name
- name: NAMESPACE_NAME
  valueFrom:
    fieldRef:
      fieldPath: metadata.namespace
- name: CONTAINER_NAME
  value: my-container-name
- name: OTEL_RESOURCE_ATTRIBUTES
  value: k8s.pod.name=$(POD_NAME),k8s.namespace.name=$(NAMESPACE_NAME),k8s.container.name=$(CONTAINER_NAME)

Étapes suivantes