Usar SDKs para enviar métricas de aplicativos

Este documento ilustra como enviar métricas diretamente de aplicativos para o endpoint OTLP usando um SDK e o exportador gRPC, que é o recomendado para uso com SDKs. O endpoint OTLP oferece suporte a todos os protocolos OTLP, incluindo http/proto, http/json e grpc. Para mais informações, consulte Suporte a protocolo.

Ao enviar métricas de aplicativos diretamente para o endpoint OTLP, o coletor do OpenTelemetry não processa a autenticação e o enriquecimento para você. Ao usar SDKs para enviar métricas de aplicativos, faça o seguinte:

Antes de começar

Para executar os exemplos, ative as APIs necessárias e adquira credenciais de autenticação.

Ativar APIs

Ative a API Cloud Monitoring e a API Telemetry no seu Google Cloud projeto executando o seguinte comando:

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

Receber credenciais de autenticação

Configure as credenciais do exportador gRPC OTLP para usar as credenciais padrão do aplicativo do Google Application Default Credentials executando o seguinte comando:

gcloud auth application-default login

Exemplos específicos da linguagem

Esta seção oferece uma seleção de exemplos específicos da linguagem que criam e gravam uma métrica de contador. Selecione uma guia para informações sobre como executar o exemplo e visualizar o código.

Go

Para informações sobre como configurar e executar esse exemplo, consulte o README arquivo do exemplo do 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

Para informações sobre como configurar e executar esse exemplo, consulte o README arquivo para o exemplo do 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

Para informações sobre como configurar e executar esse exemplo, consulte o README arquivo do exemplo do 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

Para informações sobre como executar esse exemplo, consulte o arquivo README para o README arquivo para o exemplo do 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()

Usar a API downward para aplicativos executados como pods

Se você estiver executando o aplicativo como um pod no Kubernetes e não estiver enviando pelo coletor do OpenTelemetry, use a API downward para definir atributos de recursos do 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)

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