This second installment of the series will cover building an Express backend for the bookmarklet and the process of deploying it using AWS Lamda and AWS API Gateway. One of the more difficult aspects of making this work is transcoding the content to an MP3 format on Lambda, which we covered in the first part of this tutorial. Your browser does not support the video tag.
The basic interaction flow is that you click on the bookmarklet while on the page for a specific video, a new tab opens and displays a progress bar for the conversion, and then the download starts automatically as soon as it’s ready. The end result will be a browser bookmarklet which can be used to convert YouTube videos to MP3s and download them. Let’s focus on the easy part first: what we’ll be building in this tutorial.
