I answered a very similar question to this one last week.
It was probably considered "polling" since you were asking for a
framework to do something, and the details about that framework
weren't clearly pointed out (many people don't think to read the tags
for important info about the question).
Most polling questions that simply ask for a framework or a library
end up as a big list of links pointing to everyone's favorite
framework/library, which is typically why those questions get closed
as "not constructive".
SE doesn't want to get turned into a link farm, so it tends to discourage questions that only ask for links.
A better way of phrasing your question would be to outline the problem you are trying to solve (Metadata pages for all registered formats, and support for additional specific end-point types), and ask how that can be accomplished in your technology of choice.
You may get an answer pointing to an existing framework, or you may get an answer explaining how you would do that yourself in your code. But the end result is an answer that anyone can use when they come across the same problem.
That said, I have seen a few questions asking for frameworks survive, however they are usually very specific about the exact features of the framework/library wanted, and are phrased to elicit the name of that one framework that matches the description, and doesn't result in a huge list of links going to many different frameworks that may or may not answer the question.