PHP实现知识问答网站的通知和消息推送

<?php

function generateNotification($user_id, $content) {
    $sql = "INSERT INTO notifications (user_id, content, created_at) VALUES (?, ?, NOW())";
    // 使用预处理语句减少 SQL 注入风险
    $stmt = $pdo->prepare($sql);
    $stmt->execute([$user_id, $content]);
}

// 生成通知示例
$user_id = 1;
$content = "您的问题有新回答";
generateNotification($user_id, $content);
?>

<?php

function getNotifications($user_id) {
    $sql = "SELECT * FROM notifications WHERE user_id = ? ORDER BY created_at DESC";
    $stmt = $pdo->prepare($sql);
    $stmt->execute([$user_id]);
    return $stmt->fetchAll(PDO::FETCH_ASSOC);
}

function markAsRead($notification_id) {
    $sql = "UPDATE notifications SET is_read = 1 WHERE id = ?";
    $stmt = $pdo->prepare($sql);
    $stmt->execute([$notification_id]);
}

// 获取用户通知示例
$user_id = 1;
$notifications = getNotifications($user_id);
foreach ($notifications as $notification) {
    echo $notification['content'];
    markAsRead($notification['id']);
}
?>

<?php

$server = new SwooleWebsocketServer("127.0.0.1", 9502);

$server->on('open', function (SwooleWebsocketServer $server, $request) {
    echo "用户 {$request->fd} 连接成功
";
});

$server->on('message', function (SwooleWebsocketServer $server, $frame) {
    echo "收到来自用户 {$frame->fd} 的消息: {$frame->data}
";
});

$server->on('close', function ($ser, $fd) {
    echo "连接关闭：{$fd}
";
});

$server->start();
?>

<?php

$user_id = 1; // 发送消息的用户ID

function pushNotification($user_id, $content) {
    // 向用户发送消息
    // 这里省略具体的代码，可使用 $server->push 方法实现。
}

// 用户操作的代码示例
// ...

// 用户操作后发送消息示例
$content = "您关注的问题有新回答";
pushNotification($user_id, $content);
?>