如何在 MS Azure 中调试 PHP

Locally I use OS X running Apache and everything works ok. When I deploy the project to Azure, I get an error. After some debugging I isolated the error to this snippet of code:

private function getToken(){
    $ch = curl_init($this->host . $this->clientId . "&client_secret=" . $this->clientSecret);
    curl_setopt($ch,  CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HTTPHEADER, array('accept: application/json',));
    $response = json_decode(curl_exec($ch));
    curl_close($ch);
    $token = $response->access_token;
    dvm($response, $name = NULL);
    return $token;
}

dvm() 是一个 Drupal Devel 函数，但足以说它有点像 Drupal 的 print_r.