capture.js

const puppeteer = require('puppeteer');
const { Storage } = require('@google-cloud/storage');

const url: string = '';

const bucketName = '';
const fileName = `hoge-${Date.now()}.png`;

(async () => {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  await page.setViewport({ width: 1600, height: 950 });
  const response = await page.goto(url);

  const element = await page.$('.hoge');
  if (element === null) {
    throw new Error('`elements` is null.');
  }
  await element.screenshot({ path: fileName });

  await uploadFile(bucketName, fileName);
  await makePublic(bucketName, fileName);

  await browser.close();
})().catch(e => console.error(e));

// https://github.com/googleapis/nodejs-storage/blob/859b3e03b6c5419c9d056f39c56dbf972df96c99/samples/files.js
async function uploadFileToGCS(bucketName: string, filename: string) {
  // Uploads a local file to the bucket
  try {
    await storage.bucket(bucketName).upload(filename, {
      // Support for HTTP requests made with `Accept-Encoding: gzip`
      gzip: true,
      // By setting the option `destination`, you can change the name of the
      // object you are uploading to a bucket.
      metadata: {
        // Enable long-lived HTTP caching headers
        // Use only if the contents of the file will never change
        // (If the contents will change, use cacheControl: 'no-cache')
        cacheControl: 'public, max-age=31536000',
      },
    });

    console.log(`${filename} uploaded to ${bucketName}.`);
    // [END storage_upload_file]
  } catch (e) {
    console.error(e);
  }
}

async function makePublic(bucketName: string, filename: string) {
  // Makes the file public
  try {
    await storage
      .bucket(bucketName)
      .file(filename)
      .makePublic();

    console.log(`gs://${bucketName}/${filename} is now public.`);
    // [END storage_make_public]
  } catch (e) {
    console.error(e);
  }
}