cURL request Spotify API Unexpected status: 415

Well, seems I found the answer based on this question :

    $url = 'https://accounts.spotify.com/api/token';    $method = 'POST';    $spot_api_redirect = 'myurl';    $credentials = "client:secret";    $headers = array(            "Accept: */*",            "Content-Type: application/x-www-form-urlencoded",            "User-Agent: runscope/0.1",            "Authorization: Basic " . base64_encode($credentials));    $data = 'grant_type=authorization_code&code='.$_GET['code'].'&redirect_uri='.urlencode($spot_api_redirect);    if(isset($_GET['state']) && isset($_COOKIE['stateKey']) && $_COOKIE['stateKey'] == $_GET['state']){        unset($_COOKIE['stateKey']);        $ch = curl_init();        curl_setopt($ch, CURLOPT_URL, $url);        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);        curl_setopt($ch, CURLOPT_POST, 1);        curl_setopt($ch, CURLOPT_POSTFIELDS, $data);        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);        $response = json_decode(curl_exec($ch), true);        curl_close($ch);        print_r($response);    }

Just in case of node.js / request use, point out "WTF" tag :)

request(    {        method : "POST",        url : "https://accounts.spotify.com/api/token",        json : true,        headers :         {            "Content-Type" : "application/x-www-form-urlencoded", // WTF!            "Authorization" : "Basic " + new Buffer(client_id+":"+client_secret).toString('base64')        },        body : "grant_type=client_credentials"    },    function (err, response, body)    {        if (err)        {            cb(err);        }        else        {            if (body.hasOwnProperty("access_token"))            {                access_token = body.access_token;                cb(null);            }            else            {                cb(body);            }        }    });