PiwikTracker::sendRequest PHP Method

    protected function sendRequest($url, $method = 'GET', $data = null, $force = false)
    {
        self::$DEBUG_LAST_REQUESTED_URL = $url;
        // if doing a bulk request, store the url
        if ($this->doBulkRequests && !$force) {
            $this->storedTrackingActions[] = $url . (!empty($this->userAgent) ? '&ua=' . urlencode($this->userAgent) : '') . (!empty($this->acceptLanguage) ? '&lang=' . urlencode($this->acceptLanguage) : '');
            // Clear custom variables so they don't get copied over to other users in the bulk request
            $this->clearCustomVariables();
            $this->clearCustomTrackingParameters();
            $this->userAgent = false;
            $this->acceptLanguage = false;
            return true;
        }
        $proxy = $this->getProxy();
        if (function_exists('curl_init') && function_exists('curl_exec')) {
            $options = array(CURLOPT_URL => $url, CURLOPT_USERAGENT => $this->userAgent, CURLOPT_HEADER => true, CURLOPT_TIMEOUT => $this->requestTimeout, CURLOPT_RETURNTRANSFER => true, CURLOPT_HTTPHEADER => array('Accept-Language: ' . $this->acceptLanguage));
            if (defined('PATH_TO_CERTIFICATES_FILE')) {
                $options[CURLOPT_CAINFO] = PATH_TO_CERTIFICATES_FILE;
            }
            if (isset($proxy)) {
                $options[CURLOPT_PROXY] = $proxy;
            }
            switch ($method) {
                case 'POST':
                    $options[CURLOPT_POST] = true;
                    break;
                default:
                    break;
            }
            // only supports JSON data
            if (!empty($data)) {
                $options[CURLOPT_HTTPHEADER][] = 'Content-Type: application/json';
                $options[CURLOPT_HTTPHEADER][] = 'Expect:';
                $options[CURLOPT_POSTFIELDS] = $data;
            }
            $ch = curl_init();
            curl_setopt_array($ch, $options);
            ob_start();
            $response = @curl_exec($ch);
            ob_end_clean();
            $content = '';
            if (!empty($response)) {
                list($header, $content) = explode("\r\n\r\n", $response, $limitCount = 2);
            }
        } elseif (function_exists('stream_context_create')) {
            $stream_options = array('http' => array('method' => $method, 'user_agent' => $this->userAgent, 'header' => "Accept-Language: " . $this->acceptLanguage . "\r\n", 'timeout' => $this->requestTimeout));
            if (isset($proxy)) {
                $stream_options['http']['proxy'] = $proxy;
            }
            // only supports JSON data
            if (!empty($data)) {
                $stream_options['http']['header'] .= "Content-Type: application/json \r\n";
                $stream_options['http']['content'] = $data;
            }
            $ctx = stream_context_create($stream_options);
            $response = file_get_contents($url, 0, $ctx);
            $content = $response;
        }
        return $content;
    }