本文共 8670 字，大约阅读时间需要 28 分钟。

欢迎访问我的博客，

最近的一个项目在开发一个iphone客户端，客户提出要做一个程序即使在后台也可以弹出的消息提示，这是目前大量ios应用的方式，找了点资料研究了一下，现在总结出来
1.什么是Apns?

2.Apns的原理及流程

3.Apns的几个接口
push是指通过自己的服务器给用户手机的固定应用发信息

feedback是指定期从苹果那里取到一些不再能接收此应用信息的手机id，例如当用户卸载应用后，就不会再发送成功，所以这时候不要再给此用户发送信息了

4.PHP Demo
我采用了Google code中的一个项目，代码写的比较严谨，但是第一次用，有许多不明白的地方，所以研究后做下说明，告诉大家，如下：

项目地址：http://code.google.com/p/apns-php/

这个项目通过socket用ssl去连接苹果服务器的时候，没有传入密码（一般都有的），我做了一些修改，修改后可以成功的给申请过应用的手机下发信息

sample_push.php：下发测试代码，我修改的地方如下：

$push = new ApnsPHP_Push(	ApnsPHP_Abstract::ENVIRONMENT_SANDBOX,	'my.pem',//我的证书	'abc@123'//我修改的，增加了密码);

   _nEnvironment = $nEnvironment;		if (!is_readable($sProviderCertificateFile)) {			throw new ApnsPHP_Exception(				"Unable to read certificate file '{$sProviderCertificateFile}'"			);		}		$this->_sProviderCertificateFile = $sProviderCertificateFile;		$this->_sProviderPass = $sProviderPass;		$this->_nConnectTimeout = ini_get("default_socket_timeout");		$this->_nConnectRetryInterval = self::CONNECT_RETRY_INTERVAL;		$this->_nSocketSelectTimeout = self::SOCKET_SELECT_TIMEOUT;	}	/**	 * Set the Logger instance to use for logging purpose.	 *	 * The default logger is ApnsPHP_Log_Embedded, an instance	 * of ApnsPHP_Log_Interface that simply print to standard	 * output log messages.	 *	 * To set a custom logger you have to implement ApnsPHP_Log_Interface	 * and use setLogger, otherwise standard logger will be used.	 *	 * @see ApnsPHP_Log_Interface	 * @see ApnsPHP_Log_Embedded	 *	 * @param  $logger @type ApnsPHP_Log_Interface Logger instance.	 * @throws ApnsPHP_Exception if Logger is not an instance	 *         of ApnsPHP_Log_Interface.	 */	public function setLogger(ApnsPHP_Log_Interface $logger)	{		if (!is_object($logger)) {			throw new ApnsPHP_Exception(				"The logger should be an instance of 'ApnsPHP_Log_Interface'"			);		}		if (!($logger instanceof ApnsPHP_Log_Interface)) {			throw new ApnsPHP_Exception(				"Unable to use an instance of '" . get_class($logger) . "' as logger: " .				"a logger must implements ApnsPHP_Log_Interface."			);		}		$this->_logger = $logger;	}	/**	 * Get the Logger instance.	 *	 * @return @type ApnsPHP_Log_Interface Current Logger instance.	 */	public function getLogger()	{		return $this->_logger;	}	/**	 * Set the Root Certification Authority file.	 *	 * Setting the Root Certification Authority file automatically set peer verification	 * on connect.	 *	 * @see http://tinyurl.com/GeneralProviderRequirements	 * @see http://www.entrust.net/	 * @see https://www.entrust.net/downloads/root_index.cfm	 *	 * @param  $sRootCertificationAuthorityFile @type string Root Certification	 *         Authority file.	 * @throws ApnsPHP_Exception if Root Certification Authority	 *         file is not readable.	 */	public function setRootCertificationAuthority($sRootCertificationAuthorityFile)	{		if (!is_readable($sRootCertificationAuthorityFile)) {			throw new ApnsPHP_Exception(				"Unable to read Certificate Authority file '{$sRootCertificationAuthorityFile}'"			);		}		$this->_sRootCertificationAuthorityFile = $sRootCertificationAuthorityFile;	}	/**	 * Get the Root Certification Authority file path.	 *	 * @return @type string Current Root Certification Authority file path.	 */	public function getCertificateAuthority()	{		return $this->_sRootCertificationAuthorityFile;	}	/**	 * Set the connection timeout.	 *	 * The default connection timeout is the PHP internal value "default_socket_timeout".	 * @see http://php.net/manual/en/filesystem.configuration.php	 *	 * @param  $nTimeout @type integer Connection timeout in seconds.	 */	public function setConnectTimeout($nTimeout)	{		$this->_nConnectTimeout = (int)$nTimeout;	}	/**	 * Get the connection timeout.	 *	 * @return @type integer Connection timeout in seconds.	 */	public function getConnectTimeout()	{		return $this->_nConnectTimeout;	}	/**	 * Set the connect retry times value.	 *	 * If the client is unable to connect to the server retries at least for this	 * value. The default connect retry times is 3.	 *	 * @param  $nRetryTimes @type integer Connect retry times.	 */	public function setConnectRetryTimes($nRetryTimes)	{		$this->_nConnectRetryTimes = (int)$nRetryTimes;	}	/**	 * Get the connect retry time value.	 *	 * @return @type integer Connect retry times.	 */	public function getConnectRetryTimes()	{		return $this->_nConnectRetryTimes;	}	/**	 * Set the connect retry interval.	 *	 * If the client is unable to connect to the server retries at least for ConnectRetryTimes	 * and waits for this value between each attempts.	 *	 * @see setConnectRetryTimes	 *	 * @param  $nRetryInterval @type integer Connect retry interval in micro seconds.	 */	public function setConnectRetryInterval($nRetryInterval)	{		$this->_nConnectRetryInterval = (int)$nRetryInterval;	}	/**	 * Get the connect retry interval.	 *	 * @return @type integer Connect retry interval in micro seconds.	 */	public function getConnectRetryInterval()	{		return $this->_nConnectRetryInterval;	}	/**	 * Set the TCP socket select timeout.	 *	 * After writing to socket waits for at least this value for read stream to	 * change status.	 *	 * In Apple Push Notification protocol there isn't a real-time	 * feedback about the correctness of notifications pushed to the server; so after	 * each write to server waits at least SocketSelectTimeout. If, during this	 * time, the read stream change its status and socket received an end-of-file	 * from the server the notification pushed to server was broken, the server	 * has closed the connection and the client needs to reconnect.	 *	 * @see http://php.net/stream_select	 *	 * @param  $nSelectTimeout @type integer Socket select timeout in micro seconds.	 */	public function setSocketSelectTimeout($nSelectTimeout)	{		$this->_nSocketSelectTimeout = (int)$nSelectTimeout;	}	/**	 * Get the TCP socket select timeout.	 *	 * @return @type integer Socket select timeout in micro seconds.	 */	public function getSocketSelectTimeout()	{		return $this->_nSocketSelectTimeout;	}	/**	 * Connects to Apple Push Notification service server.	 *	 * Retries ConnectRetryTimes if unable to connect and waits setConnectRetryInterval	 * between each attempts.	 *	 * @see setConnectRetryTimes	 * @see setConnectRetryInterval	 * @throws ApnsPHP_Exception if is unable to connect after	 *         ConnectRetryTimes.	 */	public function connect()	{		$bConnected = false;		$nRetry = 0;		while (!$bConnected) {			try {				$bConnected = $this->_connect();			} catch (ApnsPHP_Exception $e) {				$this->_log('ERROR: ' . $e->getMessage());				if ($nRetry >= $this->_nConnectRetryTimes) {					throw $e;				} else {					$this->_log(						"INFO: Retry to connect (" . ($nRetry+1) .						"/{$this->_nConnectRetryTimes})..."					);					usleep($this->_nConnectRetryInterval);				}			}			$nRetry++;		}	}	/**	 * Disconnects from Apple Push Notifications service server.	 *	 * @return @type boolean True if successful disconnected.	 */	public function disconnect()	{		if (is_resource($this->_hSocket)) {			$this->_log('INFO: Disconnected.');			return fclose($this->_hSocket);		}		return false;	}	/**	 * Connects to Apple Push Notification service server.	 *	 * @throws ApnsPHP_Exception if is unable to connect.	 * @return @type boolean True if successful connected.	 */	protected function _connect()	{		$sURL = $this->_aServiceURLs[$this->_nEnvironment];		unset($aURLs);		$this->_log("INFO: Trying {$sURL}...");		/**		 * @see http://php.net/manual/en/context.ssl.php		 */		$streamContext = stream_context_create(array('ssl' => array(			//'verify_peer' => isset($this->_sRootCertificationAuthorityFile),			//'cafile' => $this->_sRootCertificationAuthorityFile,			'local_cert' => $this->_sProviderCertificateFile,			'passphrase'=> $this->_sProviderPass//modify by paul		)));		$this->_hSocket = @stream_socket_client($sURL, $nError, $sError,			$this->_nConnectTimeout, STREAM_CLIENT_CONNECT, $streamContext);		if (!$this->_hSocket) {			throw new ApnsPHP_Exception(				"Unable to connect to '{$sURL}': {$sError} ({$nError})"			);		}		stream_set_blocking($this->_hSocket, 0);		stream_set_write_buffer($this->_hSocket, 0);		$this->_log("INFO: Connected to {$sURL}.");		return true;	}	/**	 * Logs a message through the Logger.	 *	 * @param  $sMessage @type string The message.	 */	protected function _log($sMessage)	{		if (!isset($this->_logger)) {			$this->_logger = new ApnsPHP_Log_Embedded();		}		$this->_logger->log($sMessage);	}}

5.Pythoh Demo

http://code.google.com/p/apns-python-wrapper/

注意事项：

无论你是在sandbox，还是正式环境下，都是需要申请证书才能连接apns服务的，所以不要心存侥幸，申请的流程自己去搜索一下，值得说明的证书分.p12和.pem格式2种，.net用p12，而下面的php项目用的是pem，这个pem是用苹果下载的2个pem合并的，方法别人也介绍过了，用这个证书，加上密码（如果有密码的话），就可以通过ssl(https)去连接服务器了，这些都正确，你才会连接成功，那才能给手机发信息哦

转载地址：http://uwwci.baihongyu.com/