Yes, I read it all. And I still have questions.
Unforchantly, this guide does not cover hooking in .rb files.
For example users like to upload PUPs sometimes (potentially unwanted program), so I want to protect my main domain from being banned by Google and Antiviruses.
For Example, I need to replace cooked download links in my plugin:
“https://discourse.example.com/uploads/short-url/...exe” => “https://download.proxy.com/uploads/short-url/....exe”.
What should I do? I think I need to find some method first? But which one? How to find which one I need? How to hook it in the plugin? Should I replace or extend the method? How to do both? And many more.