@google-cloud/pubsub

@google-cloud/pubsub (Alpha)

Cloud Pub/Sub Client Library for Node.js

Looking for more Google APIs than just Pub/Sub? You might want to check out google-cloud.

• API Documentation
• Official Documentation

$ npm install --save @google-cloud/pubsub

var pubsub = require('@google-cloud/pubsub')({
  projectId: 'grape-spaceship-123',
  keyFilename: '/path/to/keyfile.json'
});

// Reference a topic that has been previously created.
var topic = pubsub.topic('my-topic');

// Publish a message to the topic.
topic.publish('New message!', function(err) {});

// Subscribe to the topic.
topic.subscribe('subscription-name', function(err, subscription) {
  // Register listeners to start pulling for messages.
  function onError(err) {}
  function onMessage(message) {}
  subscription.on('error', onError);
  subscription.on('message', onMessage);

  // Remove listeners to stop pulling for messages.
  subscription.removeListener('message', onMessage);
  subscription.removeListener('error', onError);
});

// Promises are also supported by omitting callbacks.
topic.publish('New message!').then(function(data) {
  var messageIds = data[0];
});

// It's also possible to integrate with third-party Promise libraries.
var pubsub = require('@google-cloud/pubsub')({
  promise: require('bluebird')
});

Authentication

It's incredibly easy to get authenticated and start using Google's APIs. You can set your credentials on a global basis as well as on a per-API basis. See each individual API section below to see how you can auth on a per-API-basis. This is useful if you want to use different accounts for different Cloud services.

On Google Cloud Platform

If you are running this client on Google Cloud Platform, we handle authentication for you with no configuration. You just need to make sure that when you set up the GCE instance, you add the correct scopes for the APIs you want to access.

var pubsub = require('@google-cloud/pubsub')();
// ...you're good to go!

Elsewhere

If you are not running this client on Google Cloud Platform, you need a Google Developers service account. To create a service account:

1. Visit the Google Developers Console.
2. Create a new project or click on an existing project.
3. Navigate to APIs & auth > APIs section and turn on the following APIs (you may need to enable billing in order to use these services):

• Google Cloud Pub/Sub API

1. Navigate to APIs & auth > Credentials and then:

• If you want to use a new service account key, click on Create credentials and select Service account key. After the account key is created, you will be prompted to download the JSON key file that the library uses to authenticate your requests.
• If you want to generate a new service account key for an existing service account, click on Generate new JSON key and download the JSON key file.

var projectId = process.env.GCLOUD_PROJECT; // E.g. 'grape-spaceship-123'

var pubsub = require('@google-cloud/pubsub')({
  projectId: projectId,

  // The path to your key file:
  keyFilename: '/path/to/keyfile.json'

  // Or the contents of the key file:
  credentials: require('./path/to/keyfile.json')
});

// ...you're good to go!