'use strict';

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

const pubsub = new PubSub();
const logging = new Logging();

exports.publish = (req, res) => {
  
  const random = Math.random();
  
  // Uncomment for custom logging
  const log = logging.log("my-log");
  const entry = log.entry({resource: {
    type: 'global',
    labels: {
      project_id: process.env.GCLOUD_PROJECT,
    }
  }}, 'Hello World');
  log.write(entry);
  console.log(`Wrote a log`);

  const message = JSON.stringify({
    message: random.toString(36).substring(2, 15),
  });
  
  console.log('Publishing message "'+message+'" to topic');

  return pubsub
    .topic('projects/toto-228009/topics/example')
    .publisher()
    .publish(Buffer.from(message))
    .then(() => res.status(200).send('Message published.'))
    .catch(err => {
      console.error(err);
      res.status(500).send(err);
      return Promise.reject(err);
    });
};