AWS Lambda to download youtube videos to S3

aws-lambda-youtube-dl.js

// To use this, put it in a folder, install ytdl-core with `npm i ytdl-core`, then create a ZIP with the content of the folder and deploy it.
// https://docs.aws.amazon.com/lambda/latest/dg/nodejs-package.html#nodejs-package-dependencies

var AWS = require('aws-sdk');
const ytdl = require('ytdl-core');
const stream = require('stream');
var s3 = new AWS.S3();

exports.handler = async (event, context, cb) => {
  const { videoUrl, key, bucket } = event;
  const bucketName = bucket || process.env.BUCKET;
  const keyName = `${key}-${context.awsRequestId}.mp4`;

  const uploadStream = ({ Bucket, Key }) => {
  const pass = new stream.PassThrough();
  return {
    writeStream: pass,
    promise: s3.upload({Bucket, Key, Body: pass}).promise(),
  };
}

const { writeStream, promise } = uploadStream({Bucket: bucketName , Key: keyName});
const pipeline = ytdl(videoUrl).pipe(writeStream);
 
return promise
  .then(() => `Upload completed successfully. Find it at ${bucketName}/${keyName}`))
  .catch((err) => {
    return ('Upload failed.', err.message);
  });
};