In Python, the framework Flask has a method on its AcceptHeaders equivalent called best_match which basically compares the Accept header with your list of available content-types and returns the best match.

I found myself implementing this manually in an abstract controller class:

foreach ($request->getAcceptableContentTypes() as $type) {
	if ($type == 'application/json') { return $type; }
	if ($type == 'text/plain') { return $type; }
	if ($type == 'text/html') { return $type; }
}
return 'text/plain';

Is this something that could be added to the AcceptHeaders class?

PS: I wasn't able to find any info on what RFC yes/no entails so I might have put the wrong thing there.

(edit by @lyrixx: Yes, it's a RFC, I fixed the PR description. Thanks)