php实现推送消息

PHP 实现推送消息的方法

使用 WebSocket 实现实时推送

WebSocket 是一种在单个 TCP 连接上进行全双工通信的协议，适合实现实时消息推送。

安装 Ratchet 库（WebSocket 实现）：

composer require cboden/ratchet

创建 WebSocket 服务器：

use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;

class PushServer implements MessageComponentInterface {
    protected $clients;

    public function __construct() {
        $this->clients = new \SplObjectStorage;
    }

    public function onOpen(ConnectionInterface $conn) {
        $this->clients->attach($conn);
    }

    public function onMessage(ConnectionInterface $from, $msg) {
        foreach ($this->clients as $client) {
            $client->send($msg);
        }
    }

    public function onClose(ConnectionInterface $conn) {
        $this->clients->detach($conn);
    }

    public function onError(ConnectionInterface $conn, \Exception $e) {
        $conn->close();
    }
}

$server = new \Ratchet\App('localhost', 8080);
$server->route('/push', new PushServer);
$server->run();

客户端连接代码：

const socket = new WebSocket('ws://localhost:8080/push');
socket.onmessage = function(e) {
    console.log('收到消息:', e.data);
};

使用 Server-Sent Events (SSE)

SSE 允许服务器向客户端推送事件，适合单向消息推送场景。

服务器端实现：

header('Content-Type: text/event-stream');
header('Cache-Control: no-cache');
header('Connection: keep-alive');

function sendMessage($id, $message) {
    echo "id: $id\n";
    echo "data: $message\n\n";
    ob_flush();
    flush();
}

while(true) {
    $time = date('r');
    sendMessage(time(), "服务器时间: {$time}");
    sleep(1);
}

客户端实现：

const eventSource = new EventSource('sse.php');
eventSource.onmessage = function(e) {
    console.log('新消息:', e.data);
};

使用第三方推送服务

Firebase Cloud Messaging (FCM) 实现：

function sendFCM($token, $message) {
    $url = 'https://fcm.googleapis.com/fcm/send';
    $fields = [
        'to' => $token,
        'notification' => [
            'title' => '新消息',
            'body' => $message
        ]
    ];

    $headers = [
        'Authorization: key=YOUR_SERVER_KEY',
        'Content-Type: application/json'
    ];

    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($fields));
    $result = curl_exec($ch);
    curl_close($ch);

    return $result;
}

使用长轮询技术

实现简单的长轮询机制：

// 服务器端
$lastEventId = $_SERVER['HTTP_LAST_EVENT_ID'] ?? 0;
while(true) {
    $newData = checkForNewData($lastEventId);
    if($newData) {
        header('Content-Type: application/json');
        echo json_encode($newData);
        exit;
    }
    sleep(1);
}

// 客户端
function longPoll() {
    fetch('poll.php')
        .then(response => response.json())
        .then(data => {
            processData(data);
            longPoll();
        });
}

使用消息队列系统

结合 RabbitMQ 实现消息推送：

// 生产者
$connection = new AMQPConnection([
    'host' => 'localhost',
    'port' => 5672,
    'login' => 'guest',
    'password' => 'guest'
]);
$connection->connect();

$channel = new AMQPChannel($connection);
$exchange = new AMQPExchange($channel);
$exchange->publish('消息内容', 'routing_key');

// 消费者
$queue = new AMQPQueue($channel);
$queue->setName('queue_name');
$queue->consume(function(AMQPEnvelope $envelope) {
    echo $envelope->getBody();
    return false; // 返回false以ack消息
});

每种方法适用于不同场景：WebSocket 适合实时双向通信，SSE 适合服务器向客户端推送，第三方服务适合移动端推送，长轮询兼容性最好但效率较低，消息队列适合分布式系统。