index.js

20260401_Google Skills Lab_Set Up an App Dev Environment on Google Cloud: Challenge Lab_index.js

const functions = require('@google-cloud/functions-framework');
const { Storage } = require('@google-cloud/storage');
const { PubSub } = require('@google-cloud/pubsub');
const sharp = require('sharp');
// Read FUNCTION_NAME from env variable
const FUNCTION_NAME = process.env.FUNCTION_NAME;

// functions.cloudEvent('memories-thumbnail-creator', async cloudEvent => {
functions.cloudEvent(FUNCTION_NAME, async cloudEvent => {
  const event = cloudEvent.data;

  console.log(`Event: ${JSON.stringify(event)}`);
  console.log(`Hello ${event.bucket}`);

  const fileName = event.name;
  const bucketName = event.bucket;
  const size = "64x64";
  const bucket = new Storage().bucket(bucketName);
//   const topicName = "topic-memories-993";
  const topicName = process.env.TOPIC_NAME;
  const pubsub = new PubSub();

  if (fileName.search("64x64_thumbnail") === -1) {
    // doesn't have a thumbnail, get the filename extension
    const filename_split = fileName.split('.');
    const filename_ext = filename_split[filename_split.length - 1].toLowerCase();
    const filename_without_ext = fileName.substring(0, fileName.length - filename_ext.length - 1); // fix sub string to remove the dot

    if (filename_ext === 'png' || filename_ext === 'jpg' || filename_ext === 'jpeg') {
      // only support png and jpg at this point
      console.log(`Processing Original: gs://${bucketName}/${fileName}`);
      const gcsObject = bucket.file(fileName);
      const newFilename = `${filename_without_ext}_64x64_thumbnail.${filename_ext}`;
      const gcsNewObject = bucket.file(newFilename);

      try {
        const [buffer] = await gcsObject.download();
        const resizedBuffer = await sharp(buffer)
          .resize(64, 64, {
            fit: 'inside',
            withoutEnlargement: true,
          })
          .toFormat(filename_ext)
          .toBuffer();

        await gcsNewObject.save(resizedBuffer, {
          metadata: {
            contentType: `image/${filename_ext}`,
          },
        });

        console.log(`Success: ${fileName} → ${newFilename}`);

        await pubsub
          .topic(topicName)
          .publishMessage({ data: Buffer.from(newFilename) });

        console.log(`Message published to ${topicName}`);
      } catch (err) {
        console.error(`Error: ${err}`);
      }
    } else {
      console.log(`gs://${bucketName}/${fileName} is not an image I can handle`);
    }
  } else {
    console.log(`gs://${bucketName}/${fileName} already has a thumbnail`);
  }
});