Zend_Http_Client::encodeAuthHeader PHP Method

    public static function encodeAuthHeader($user, $password, $type = self::AUTH_BASIC)
    {
        $authHeader = null;
        switch ($type) {
            case self::AUTH_BASIC:
                // In basic authentication, the user name cannot contain ":"
                if (strpos($user, ':') !== false) {
                    /** @see Zend_Http_Client_Exception */
                    require_once 'Zend/Http/Client/Exception.php';
                    throw new Zend_Http_Client_Exception("The user name cannot contain ':' in 'Basic' HTTP authentication");
                }
                $authHeader = 'Basic ' . base64_encode($user . ':' . $password);
                break;
                //case self::AUTH_DIGEST:
                /**
                 * @todo Implement digest authentication
                 */
                //    break;
            //case self::AUTH_DIGEST:
            /**
             * @todo Implement digest authentication
             */
            //    break;
            default:
                /** @see Zend_Http_Client_Exception */
                require_once 'Zend/Http/Client/Exception.php';
                throw new Zend_Http_Client_Exception("Not a supported HTTP authentication type: '{$type}'");
        }
        return $authHeader;
    }

 /**
  * Send request to the proxy server with streaming support
  *
  * @param string        $method
  * @param Zend_Uri_Http $uri
  * @param string        $http_ver
  * @param array         $headers
  * @param string        $body
  * @return string Request as string
  */
 public function write($method, $uri, $http_ver = '1.1', $headers = array(), $body = '')
 {
     // If no proxy is set, throw an error
     if (!$this->config['proxy_host']) {
         // require_once 'Zend/Http/Client/Adapter/Exception.php';
         throw new Zend_Http_Client_Adapter_Exception('No proxy host set!');
     }
     // Make sure we're properly connected
     if (!$this->socket) {
         // require_once 'Zend/Http/Client/Adapter/Exception.php';
         throw new Zend_Http_Client_Adapter_Exception('Trying to write but we are not connected');
     }
     $host = $this->config['proxy_host'];
     $port = $this->config['proxy_port'];
     if ($this->connected_to[0] != $host || $this->connected_to[1] != $port) {
         // require_once 'Zend/Http/Client/Adapter/Exception.php';
         throw new Zend_Http_Client_Adapter_Exception('Trying to write but we are connected to the wrong proxy ' . 'server');
     }
     // Add Proxy-Authorization header
     if ($this->config['proxy_user'] && !isset($headers['proxy-authorization'])) {
         $headers['proxy-authorization'] = Zend_Http_Client::encodeAuthHeader($this->config['proxy_user'], $this->config['proxy_pass'], $this->config['proxy_auth']);
     }
     // if we are proxying HTTPS, preform CONNECT handshake with the proxy
     if ($uri->getScheme() == 'https' && !$this->negotiated) {
         $this->connectHandshake($uri->getHost(), $uri->getPort(), $http_ver, $headers);
         $this->negotiated = true;
     }
     // Save request method for later
     $this->method = $method;
     // Build request headers
     $request = "{$method} {$uri->__toString()} HTTP/{$http_ver}\r\n";
     // Add all headers to the request string
     foreach ($headers as $k => $v) {
         if (is_string($k)) {
             $v = "{$k}: {$v}";
         }
         $request .= "{$v}\r\n";
     }
     $request .= "\r\n";
     // Send the request headers
     if (!@fwrite($this->socket, $request)) {
         // require_once 'Zend/Http/Client/Adapter/Exception.php';
         throw new Zend_Http_Client_Adapter_Exception('Error writing request to proxy server');
     }
     // Read from $body, write to socket
     $chunk = $body->read(self::CHUNK_SIZE);
     while ($chunk !== false) {
         if (!@fwrite($this->socket, $chunk)) {
             // require_once 'Zend/Http/Client/Adapter/Exception.php';
             throw new Zend_Http_Client_Adapter_Exception('Error writing request to server');
         }
         $chunk = $body->read(self::CHUNK_SIZE);
     }
     $body->closeFileHandle();
     return 'Large upload, request is not cached.';
 }