It helps you to actually trigger download of any file available on any server, and avoiding opening of the file in browser.
There are 2 ways to use it
Just create anchor tag <a> and provide link in this format
https://triggerdownload.herokuapp.com/api/download?url=YOUR_URL&filename=FILE_NAME&format=FILE_FORMAT
url = Your download URL
filename = File Name for Downloaded file
format = format/extension of the file that you want to download
Simple Example
<a href="https://triggerdownload.herokuapp.com/api/download?url=https://ytdlpro.herokuapp.com/def_thumb.jpg&filename=logo&format=jpg">Click to Trigger Download!</a>Pro Example , incase you need to pass url that contains & , we will just encode the url and then pass it. Let's assume you have to download from this url https://avatars.githubusercontent.com/u/81325730?v=4 then we will first use encodeURIComponent to remove the & from URL and then pass it in anchor tag.
Simple HTML
<a href="https://triggerdownload.herokuapp.com/api/download?url="+url+"&filename=test&format=jpg">Click to Trigger Download!</a>
<script>
const url = encodeURIComponent(https://avatars.githubusercontent.com/u/81325730?v=4)
</script>React/NextJS
<a href="https://triggerdownload.herokuapp.com/api/download?url="+encodeURIComponent(https://avatars.githubusercontent.com/u/81325730?v=4)+"&filename=test&format=jpg">Click to Trigger Download!</a>Similary, you can also pass variable as filename and format !
You can copy download.js file from public/api folder of this repository and use it as your own API and you can also customise it as per your choice.
ENJOY!