PHP Leer el cuerpo de la solicitud JSON
//e.g your JSON Req is like this {"UserName":"Ranish","Password":"asdasdasd"}
$jsonReqUrl = "php://input";
$reqjson = file_get_contents($jsonReqUrl);
$reqjsonDecode = json_decode($reqjson, true);
echo $reqjsonDecode['UserName'];
Ranish