Used createReadStream to read data from a Cloud Storage file

useCreateReadStreamWithExpress.js

app.get('/', async (req, res) => {
  const bucket = storage.bucket(bucketName);
  const file = bucket.file(fileName);
  const readStream = file.createReadStream();
  //Pipe data from the read-stream into the HTTP response body
  readStream.pipe(res); 
});