Stripe\HttpClient\CurlClient::request PHP Method

    public function request($method, $absUrl, $headers, $params, $hasFile)
    {
        $curl = curl_init();
        $method = strtolower($method);
        $opts = array();
        if (is_callable($this->defaultOptions)) {
            // call defaultOptions callback, set options to return value
            $opts = call_user_func_array($this->defaultOptions, func_get_args());
            if (!is_array($opts)) {
                throw new Error\Api("Non-array value returned by defaultOptions CurlClient callback");
            }
        } elseif (is_array($this->defaultOptions)) {
            // set default curlopts from array
            $opts = $this->defaultOptions;
        }
        if ($method == 'get') {
            if ($hasFile) {
                throw new Error\Api("Issuing a GET request with a file parameter");
            }
            $opts[CURLOPT_HTTPGET] = 1;
            if (count($params) > 0) {
                $encoded = self::encode($params);
                $absUrl = "{$absUrl}?{$encoded}";
            }
        } elseif ($method == 'post') {
            $opts[CURLOPT_POST] = 1;
            $opts[CURLOPT_POSTFIELDS] = $hasFile ? $params : self::encode($params);
        } elseif ($method == 'delete') {
            $opts[CURLOPT_CUSTOMREQUEST] = 'DELETE';
            if (count($params) > 0) {
                $encoded = self::encode($params);
                $absUrl = "{$absUrl}?{$encoded}";
            }
        } else {
            throw new Error\Api("Unrecognized method {$method}");
        }
        // Create a callback to capture HTTP headers for the response
        $rheaders = array();
        $headerCallback = function ($curl, $header_line) use(&$rheaders) {
            // Ignore the HTTP request line (HTTP/1.1 200 OK)
            if (strpos($header_line, ":") === false) {
                return strlen($header_line);
            }
            list($key, $value) = explode(":", trim($header_line), 2);
            $rheaders[trim($key)] = trim($value);
            return strlen($header_line);
        };
        // By default for large request body sizes (> 1024 bytes), cURL will
        // send a request without a body and with a `Expect: 100-continue`
        // header, which gives the server a chance to respond with an error
        // status code in cases where one can be determined right away (say
        // on an authentication problem for example), and saves the "large"
        // request body from being ever sent.
        //
        // Unfortunately, the bindings don't currently correctly handle the
        // success case (in which the server sends back a 100 CONTINUE), so
        // we'll error under that condition. To compensate for that problem
        // for the time being, override cURL's behavior by simply always
        // sending an empty `Expect:` header.
        array_push($headers, 'Expect: ');
        $absUrl = Util\Util::utf8($absUrl);
        $opts[CURLOPT_URL] = $absUrl;
        $opts[CURLOPT_RETURNTRANSFER] = true;
        $opts[CURLOPT_CONNECTTIMEOUT] = $this->connectTimeout;
        $opts[CURLOPT_TIMEOUT] = $this->timeout;
        $opts[CURLOPT_HEADERFUNCTION] = $headerCallback;
        $opts[CURLOPT_HTTPHEADER] = $headers;
        if (!Stripe::$verifySslCerts) {
            $opts[CURLOPT_SSL_VERIFYPEER] = false;
        }
        curl_setopt_array($curl, $opts);
        $rbody = curl_exec($curl);
        if (!defined('CURLE_SSL_CACERT_BADFILE')) {
            define('CURLE_SSL_CACERT_BADFILE', 77);
            // constant not defined in PHP
        }
        $errno = curl_errno($curl);
        if ($errno == CURLE_SSL_CACERT || $errno == CURLE_SSL_PEER_CERTIFICATE || $errno == CURLE_SSL_CACERT_BADFILE) {
            array_push($headers, 'X-Stripe-Client-Info: {"ca":"using Stripe-supplied CA bundle"}');
            $cert = self::caBundle();
            curl_setopt($curl, CURLOPT_HTTPHEADER, $headers);
            curl_setopt($curl, CURLOPT_CAINFO, $cert);
            $rbody = curl_exec($curl);
        }
        if ($rbody === false) {
            $errno = curl_errno($curl);
            $message = curl_error($curl);
            curl_close($curl);
            $this->handleCurlError($absUrl, $errno, $message);
        }
        $rcode = curl_getinfo($curl, CURLINFO_HTTP_CODE);
        curl_close($curl);
        return array($rbody, $rcode, $rheaders);
    }

 public function testDefaultOptions()
 {
     // make sure options array loads/saves properly
     $optionsArray = array(CURLOPT_PROXY => 'localhost:80');
     $withOptionsArray = new CurlClient($optionsArray);
     $this->assertSame($withOptionsArray->getDefaultOptions(), $optionsArray);
     // make sure closure-based options work properly, including argument passing
     $ref = null;
     $withClosure = new CurlClient(function ($method, $absUrl, $headers, $params, $hasFile) use(&$ref) {
         $ref = func_get_args();
         return array();
     });
     $withClosure->request('get', 'https://httpbin.org/status/200', array(), array(), false);
     $this->assertSame($ref, array('get', 'https://httpbin.org/status/200', array(), array(), false));
     // this is the last test case that will run, since it'll throw an exception at the end
     $withBadClosure = new CurlClient(function () {
         return 'thisShouldNotWork';
     });
     $this->setExpectedException('Stripe\\Error\\Api', "Non-array value returned by defaultOptions CurlClient callback");
     $withBadClosure->request('get', 'https://httpbin.org/status/200', array(), array(), false);
 }