I recently decided to send proper HTTP header from my PHP application.
Since I've never done that before, I have a couple of very basic questions.
Status codes 200 and 404 seem obvious.
But how about the other ones?
Is it allowed to/recommended/not recommended to use 403 for example, if the user has to log in via a HTML form in order to use the page?
How about 415 for file uploads? Would it be a good idea to set a 415 header if the user uploads an image with a non-supported extension, for example?