Symfony 2.5服务器返回500状态

When I'm doing a request into API that I've written using Symfony 2.5. I'm sending form data using POST method and in the controller I'm doing

$params = json_decode($request->getContent(), true);

and if I do

var_dump($params);

I can see everything in console If I'm doing

console.log(data)

But If I try just do something like this:

array_keys($params)

Server returns me a 500 status code and error:

XMLHttpRequest cannot load http://host.loc/app_dev.php/posts. Invalid HTTP status code 500 

You will always get 500 Error if something went completely wrong.

e.g. even use dump() in twig - which is not allowed in production

1) try the same page in /app_dev.php/[page] - enable debug, this should give you alot of info about the error

2) look at the correct log file /app/logs/ as mentioned above

I guess you calling getContent() on a null Object ;-)