xxxxxxxxxx
/*json example:
{
"expires_in":5180976,
"access_token":"AQXzQgKTpTSjs-qiBh30aMgm3_Kb53oIf-VA733BpAogVE5jpz3jujU65WJ1XXSvVm1xr2LslGLLCWTNV5Kd_8J1YUx26axkt1E-vsOdvUAgMFH1VJwtclAXdaxRxk5UtmCWeISB6rx6NtvDt7yohnaarpBJjHWMsWYtpNn6nD87n0syud0"
}
*/
$json = file_get_contents('url_here');
$obj = json_decode($json);
echo $obj->access_token;
xxxxxxxxxx
$url = "http://urlToYourJsonFile.com";
$json = file_get_contents($url);
$json_data = json_decode($json, true);
echo "My token: ". $json_data["access_token"];