getContents() returns weird characters
Hi, 

I’m on Ubuntu, i have PHP 7.0.18 and I installed "cboden/ratchet":"0.4.x-dev". 

When I send this from client side : 

 var data = { "message" : "Hello" };

I get this on server side: 

b"ü\x13{"message":"Hello"}"

(i'm using getContents() method of MessageInterface) 

Is there any explication? How can I fix it?

Thanks