You need to figure out the content type from a file name or path.  The typical use case is you are getting files from Google Cloud Storage and you don't know the content type and you need to specify a content type for video viewers.
For example you have messy  file names and file paths and you want to get the content type in your Server Side action so you can store the content type as meta data in Bubble.

file.htm  text/html
folder/file.js  application/javascript
screenshot.png image/png
recording.mov  video/mov