Utilizzare gli SDK per inviare metriche dalle applicazioni

Questo documento illustra come inviare le metriche direttamente dalle applicazioni all'endpoint OTLP utilizzando un SDK e l'esportatore gRPC, che è l'esportatore consigliato per l'utilizzo con gli SDK. L'endpoint OTLP supporta tutti i protocolli OTLP, inclusi http/proto, http/json e grpc. Per ulteriori informazioni, vedi Supporto dei protocolli.

Quando invii le metriche dell'applicazione direttamente all'endpoint OTLP, OpenTelemetry Collector non gestisce l'autenticazione e l'arricchimento per te. Quando utilizzi gli SDK per inviare metriche dalle applicazioni, devi:

Prima di iniziare

Per eseguire gli esempi, devi abilitare le API necessarie e acquisire le credenziali di autenticazione.

Abilita API

Abilita l'API Cloud Monitoring e l'API Telemetry nel tuo progettoGoogle Cloud eseguendo il seguente comando:

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

Recupera le credenziali di autenticazione

Configura le credenziali per l'esportatore gRPC OTLP in modo che utilizzi le credenziali predefinite dell'applicazione di Google eseguendo il seguente comando:

gcloud auth application-default login

Esempi specifici per lingua

Questa sezione fornisce una selezione di esempi specifici per lingua che creano e scrivono una metrica di conteggio. Seleziona una scheda per informazioni sull'esecuzione dell'esempio e per visualizzare il codice.

Go

Per informazioni sulla configurazione e l'esecuzione di questo esempio, consulta il file README per l'esempio 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

Per informazioni sulla configurazione e l'esecuzione di questo esempio, consulta il file README per l'esempio 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

Per informazioni sulla configurazione e l'esecuzione di questo esempio, consulta il file README per l'esempio 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

Per informazioni sull'esecuzione di questo esempio, consulta il file README per il file README per l'esempio 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()

Utilizzare l'API Downward per le applicazioni in esecuzione come pod

Se esegui l'applicazione come pod in Kubernetes e non invii tramite OpenTelemetry Collector, assicurati di utilizzare l'API Downward per impostare gli attributi delle risorse 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)

Passaggi successivi