Why can’t you use the code I wrote yesterday? (maybe elaborate what you’re trying to do).
Anyway, you can combine the code I posted yesterday with an http-function if that what you need.
For example, I have code snippet that my partners implement on their non-Wix website, and the src points to my Wix http function url, once I get the request, I read the file content (with the code In posted yesterday) and return it as a javascript resource.