Logging Client Libraries

This page shows how to get started with the Cloud Client Libraries for the Cloud Logging API. Read more about the client libraries for Cloud APIs, including the older Google APIs Client Libraries, in Client Libraries Explained.

Installing the client library

C#

For more information, see Setting Up a C# Development Environment.

Install-Package Google.Cloud.Logging.V2

Go

For more information, see Setting Up a Go Development Environment.

go get -u cloud.google.com/go/logging

Java

For more information, see Setting Up a Java Development Environment.

Si usas Maven con una BOM, agrega lo siguiente al archivo pom.xml:

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>com.google.cloud</groupId>
      <artifactId>libraries-bom</artifactId>
      <version>16.1.0</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>
  <dependency>
    <groupId>com.google.cloud</groupId>
    <artifactId>google-cloud-logging</artifactId>
  </dependency>
  <!-- ...
</dependencies>

Si usas Maven sin una BOM, agrega esto a las dependencias:

<dependency>
  <groupId>com.google.cloud</groupId>
  <artifactId>google-cloud-logging</artifactId>
  <version>2.1.0</version>
</dependency>

Si usas Gradle, agrega lo siguiente a las dependencias:

compile 'com.google.cloud:google-cloud-logging:2.0.1'

Si usas sbt, agrega lo siguiente a las dependencias:

libraryDependencies += "com.google.cloud" % "google-cloud-logging" % "2.0.1"

Si usas IntelliJ o Eclipse, puedes agregar bibliotecas cliente a tu proyecto mediante los siguientes complementos de IDE:

Los complementos brindan funcionalidades adicionales, como administración de claves para las cuentas de servicio. Consulta la documentación de cada complemento para obtener más detalles.

Node.js

For more information, see Setting Up a Node.js Development Environment.

npm install --save @google-cloud/logging

PHP

For more information, see Using PHP on Google Cloud.

composer require google/cloud-logging

Python

For more information, see Setting Up a Python Development Environment.

pip install --upgrade google-cloud-logging
Install the google-cloud-logging library, not an explicitly versioned library.

Ruby

For more information, see Setting Up a Ruby Development Environment.

gem install google-cloud-logging

Setting up authentication

To run the client library, you must first set up authentication by creating a service account and setting an environment variable. Complete the following steps to set up authentication. For other ways to authenticate, see the GCP authentication documentation.

Cloud Console

  1. En Cloud Console, ve a la página Crea una clave de cuenta de servicio.

    Ir a la página Crea una clave de la cuenta de servicio
  2. En la lista Cuenta de servicio, selecciona Cuenta de servicio nueva.
  3. Ingresa un nombre en el campo Nombre de cuenta de servicio.

  4. En la lista Función, selecciona Proyecto > Propietario.

  5. Haz clic en Crear. Se descargará un archivo JSON que contiene tus claves a tu computadora.

Línea de comandos

Puedes ejecutar los siguientes comandos con el SDK de Cloud en tu máquina local o en Cloud Shell.

  1. Crea la cuenta de servicio. Reemplaza NAME por un nombre para la cuenta de servicio. 

    gcloud iam service-accounts create NAME

  2. Otorga permisos a la cuenta de servicio. Reemplaza PROJECT_ID por el ID del proyecto. 

    gcloud projects add-iam-policy-binding PROJECT_ID --member="serviceAccount:NAME@PROJECT_ID.iam.gserviceaccount.com" --role="roles/owner"

  3. Genera el archivo de claves. Reemplaza FILE_NAME por un nombre para el archivo de claves. 

    gcloud iam service-accounts keys create FILE_NAME.json --iam-account=NAME@PROJECT_ID.iam.gserviceaccount.com

Configura la variable de entorno GOOGLE_APPLICATION_CREDENTIALS para proporcionar credenciales de autenticación al código de la aplicación. Reemplaza [PATH] por la ruta de acceso del archivo JSON que contiene la clave de tu cuenta de servicio. Esta variable solo se aplica a la sesión actual de shell. Por lo tanto, si abres una sesión nueva, deberás volver a configurar la variable.

Linux o macOS

export GOOGLE_APPLICATION_CREDENTIALS="[PATH]"

Por ejemplo:

export GOOGLE_APPLICATION_CREDENTIALS="/home/user/Downloads/my-key.json"

Windows

Con PowerShell:

$env:GOOGLE_APPLICATION_CREDENTIALS="[PATH]"

Por ejemplo:

$env:GOOGLE_APPLICATION_CREDENTIALS="C:\Users\username\Downloads\my-key.json"

Con el símbolo del sistema:

set GOOGLE_APPLICATION_CREDENTIALS=[PATH]

Using the client library

The following example shows how to use the client library.

C#

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 


using System;
// Imports the Google Cloud Logging client library
using Google.Cloud.Logging.V2;
using Google.Cloud.Logging.Type;
using System.Collections.Generic;
using Google.Api;

namespace GoogleCloudSamples
{
    public class QuickStart
    {
        public static void Main(string[] args)
        {
            // Your Google Cloud Platform project ID.
            string projectId = "YOUR-PROJECT-ID";

            // Instantiates a client.
            var client = LoggingServiceV2Client.Create();

            // Prepare new log entry.
            LogEntry logEntry = new LogEntry();
            string logId = "my-log";
            LogName logName = new LogName(projectId, logId);
            LogNameOneof logNameToWrite = LogNameOneof.From(logName);
            logEntry.LogName = logName.ToString();
            logEntry.Severity = LogSeverity.Info;

            // Create log entry message.
            string message = "Hello World!";
            string messageId = DateTime.Now.Millisecond.ToString();
            Type myType = typeof(QuickStart);
            string entrySeverity = logEntry.Severity.ToString().ToUpper();
            logEntry.TextPayload =
                $"{messageId} {entrySeverity} {myType.Namespace}.LoggingSample - {message}";

            // Set the resource type to control which GCP resource the log entry belongs to.
            // See the list of resource types at:
            // https://cloud.google.com/logging/docs/api/v2/resource-list
            // This sample uses resource type 'global' causing log entries to appear in the 
            // "Global" resource list of the Developers Console Logs Viewer:
            //  https://console.cloud.google.com/logs/viewer
            MonitoredResource resource = new MonitoredResource();
            resource.Type = "global";

            // Create dictionary object to add custom labels to the log entry.
            IDictionary<string, string> entryLabels = new Dictionary<string, string>();
            entryLabels.Add("size", "large");
            entryLabels.Add("color", "red");

            // Add log entry to collection for writing. Multiple log entries can be added.
            IEnumerable<LogEntry> logEntries = new LogEntry[] { logEntry };

            // Write new log entry.
            client.WriteLogEntries(logNameToWrite, resource, entryLabels, logEntries);

            Console.WriteLine("Log Entry created.");
        }
    }
}

Go

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 


// Sample logging-quickstart writes a log entry to Cloud Logging.
package main

import (
	"context"
	"fmt"
	"log"

	"cloud.google.com/go/logging"
)

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

	// Sets your Google Cloud Platform project ID.
	projectID := "YOUR_PROJECT_ID"

	// Creates a client.
	client, err := logging.NewClient(ctx, projectID)
	if err != nil {
		log.Fatalf("Failed to create client: %v", err)
	}

	// Sets the name of the log to write to.
	logName := "my-log"

	// Selects the log to write to.
	logger := client.Logger(logName)

	// Sets the data to log.
	text := "Hello, world!"

	// Adds an entry to the log buffer.
	logger.Log(logging.Entry{Payload: text})

	// Closes the client and flushes the buffer to the Cloud Logging
	// service.
	if err := client.Close(); err != nil {
		log.Fatalf("Failed to close client: %v", err)
	}

	fmt.Printf("Logged: %v\n", text)
}

Java

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 

import com.google.cloud.MonitoredResource;
import com.google.cloud.logging.LogEntry;
import com.google.cloud.logging.Logging;
import com.google.cloud.logging.LoggingOptions;
import com.google.cloud.logging.Payload.StringPayload;
import com.google.cloud.logging.Severity;
import java.util.Collections;

/**
 * This sample demonstrates writing logs using the Cloud Logging API. The library also offers
 * a java.util.logging Handler `com.google.cloud.logging.LoggingHandler` Logback integration is also
 * available :
 * https://github.com/googleapis/google-cloud-java/tree/master/google-cloud-clients/google-cloud-contrib/google-cloud-logging-logback
 * Using the java.util.logging handler / Logback appender should be preferred to using the API
 * directly.
 */
public class QuickstartSample {

  /** Expects a new or existing Cloud log name as the first argument. */
  public static void main(String... args) throws Exception {

    // Instantiates a client
    Logging logging = LoggingOptions.getDefaultInstance().getService();

    // The name of the log to write to
    String logName = args[0]; // "my-log";

    // The data to write to the log
    String text = "Hello, world!";

    LogEntry entry =
        LogEntry.newBuilder(StringPayload.of(text))
            .setSeverity(Severity.ERROR)
            .setLogName(logName)
            .setResource(MonitoredResource.newBuilder("global").build())
            .build();

    // Writes the log entry asynchronously
    logging.write(Collections.singleton(entry));

    System.out.printf("Logged: %s%n", text);
  }
}

Node.js

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 

// Imports the Google Cloud client library
const {Logging} = require('@google-cloud/logging');

async function quickstart(
  projectId = 'YOUR_PROJECT_ID', // Your Google Cloud Platform project ID
  logName = 'my-log' // The name of the log to write to
) {
  // Creates a client
  const logging = new Logging({projectId});

  // Selects the log to write to
  const log = logging.log(logName);

  // The data to write to the log
  const text = 'Hello, world!';

  // The metadata associated with the entry
  const metadata = {
    resource: {type: 'global'},
    // See: https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry#logseverity
    severity: 'INFO',
  };

  // Prepares a log entry
  const entry = log.entry(metadata, text);

  async function writeLog() {
    // Writes the log entry
    await log.write(entry);
    console.log(`Logged: ${text}`);
  }
  writeLog();
}

PHP

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 

# Includes the autoloader for libraries installed with composer
require __DIR__ . '/vendor/autoload.php';

# Imports the Google Cloud client library
use Google\Cloud\Logging\LoggingClient;

# Your Google Cloud Platform project ID
$projectId = 'YOUR_PROJECT_ID';

# Instantiates a client
$logging = new LoggingClient([
    'projectId' => $projectId
]);

# The name of the log to write to
$logName = 'my-log';

# Selects the log to write to
$logger = $logging->logger($logName);

# The data to log
$text = 'Hello, world!';

# Creates the log entry
$entry = $logger->entry($text);

# Writes the log entry
$logger->write($entry);

echo 'Logged ' . $text;

Python

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 

# Imports the Google Cloud client library
from google.cloud import logging

# Instantiates a client
logging_client = logging.Client()

# The name of the log to write to
log_name = "my-log"
# Selects the log to write to
logger = logging_client.logger(log_name)

# The data to log
text = "Hello, world!"

# Writes the log entry
logger.log_text(text)

print("Logged: {}".format(text))

Ruby

To learn how to install and use the client library for Logging, see the Logging Client Libraries. 

# Imports the Google Cloud client library
require "google/cloud/logging"

# Your Google Cloud Platform project ID
project_id = "YOUR_PROJECT_ID"

# Instantiates a client
logging = Google::Cloud::Logging.new project: project_id

# Prepares a log entry
entry = logging.entry
# The data to log
entry.payload = "Hello, world!"
# The name of the log to write to
entry.log_name = "my-log"
# The resource associated with the data
entry.resource.type = "global"

# Writes the log entry
logging.write_entries entry

puts "Logged #{entry.payload}"

Additional resources