$request_body = file_get_contents('php://input'); $data = json_decode($request_body, true); // Access data sent in the request body $username = $data['username']; $password = $data['password'];The package library for working with request body data in PHP depends on the specific use case. For example, if you are building a REST API, you might use a package like Slim or Laravel to handle request body data. If you are working with form data, you might use a package like Symfony's Form component.