How can I get request raw data in PHP?

I am designing a server which works as a proxy server in PHP. It just forwards the request from the client to server and replies the response from the server back to the开发者_JAVA技巧 client.

I want to read the raw request data of the client. It may include POST, GET, or multipart/form-data with files to be uploaded. How can I do it?

file_get_contents("php://input");

You can see more options in php:// ("Options").