// Copyright 2017-2023 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.

// This is a generated sample, using the typeless sample bot. Please

// look for the source TypeScript sample (.ts) for modifications.

'use strict';

/* eslint-disable n/no-process-exit */

// sample-metadata:

// title: Quickstart

// description: A quick introduction to using the Pub/Sub client library.

// usage: node quickstart.js <project-id> <topic-name-or-id> <subscription-name-or-id>

// [START pubsub_quickstart_create_topic]

// Imports the Google Cloud client library

const {PubSub} = require('@google-cloud/pubsub');

async function quickstart(

projectId = 'your-project-id', // Your Google Cloud Platform project ID

topicNameOrId = 'my-topic', // Name for the new topic to create

subscriptionName = 'my-sub', // Name for the new subscription to create

) {

// Instantiates a client

const pubsub = new PubSub({projectId});

// Creates a new topic

const [topic] = await pubsub.createTopic(topicNameOrId);

console.log(`Topic ${topic.name} created.`);

// Creates a subscription on that new topic

const [subscription] = await topic.createSubscription(subscriptionName);

// Receive callbacks for new messages on the subscription

subscription.on('message', message => {

console.log('Received message:', message.data.toString());

process.exit(0);

});

// Receive callbacks for errors on the subscription

subscription.on('error', error => {

console.error('Received error:', error);

process.exit(1);

});

// Send a message to the topic

await topic.publishMessage({data: Buffer.from('Test message!')});

}

// [END pubsub_quickstart_create_topic]

quickstart(...process.argv.slice(2)).catch(err => {

console.error(err.message);

process.exitCode = 1;

});