如何将 PHP 和 NodeJS 与 Redis 同步并按顺序获取数据


How to Sync PHP and NodeJS with Redis and get data in order

我有一个示例代码,用于进行实验,试图在一个简单的聊天示例中思考"如何"同步"nodejs 和 php。

这是我的 NodeJS 服务器:

var redis       = require('redis'),
    subscriber  = redis.createClient(),
    publisher   = redis.createClient();
//var sckio = require('socket.io').listen(8888);
var http = require('http');
var querystring = require('querystring');
var WebSocketServer = require('ws').Server
var ENCODING = 'utf8';
var tCounter = 0;
/* #################################### */
// Event on "subscribe" to any channel
subscriber.on("subscribe", function (channel, count) {
    // Publish to redis server Test Message
    publisher.publish("chat", "NODEJS MESSAGE");
});
// Suscrib to redis server
subscriber.on('message', function (channel, json) {
    console.log('SUB: ' + channel + ' | ' + json);
    console.log('PHP PUSH TO REDIS, AND NODE CAPTURE REDIS PUSH: ' + (getMicrotime(true) - tCounter));       
});
subscriber.subscribe('chat'); // Subs to "mysql" channel

/*
var clients = [];
sckio.sockets.on('connection', function (socket) {
  clients.push(socket);
  publisher.publish("chat", "User connected");
  socket.on('message', function (from, msg) {
    publisher.publish("chat", msg);
    clients.forEach(function (client) {
      if (client === socket) return;
      client.send(msg);
    });
  });
  socket.on('disconnect', function () {
    clients.splice(clients.indexOf(socket), 1);
    publisher.publish("chat", "User disconnected");
  });
});
*/
var wss = new WebSocketServer({port: 8888, timeout : 500});
var wsClients = [];
wss.on('connection', function(ws) {

    ws.AUTH_ID = Math.random();
    wsClients.push(ws);
    publisher.publish("chat", "User enter");
    ws.on('message', function(message) {
        wsClients.forEach(function (client) {
           client.send(ws.AUTH_ID + ' ' + message);
        });
        tCounter = getMicrotime(true);
        console.log('CALL TO PHP: ' + tCounter);
        PostCode('CODE TO PHP FROM NODE', function() {
            wsClients.forEach(function (client) {
               client.send('PHP SAVE DATA');
            });
        });
    });
    ws.on('close', function(message) {
      wsClients.splice(wsClients.indexOf(ws), 1);
      publisher.publish("chat", "User left");
    });
    ws.send('HELLO USER!');
});    
function getMicrotime(get_as_float) {
    var now = new Date().getTime() / 1000;
    var s = parseInt(now, 10);
    return (get_as_float) ? now : (Math.round((now - s) * 1000) / 1000) + ' ' + s;
}
function PostCode(codestring, callback) {
  // Build the post string from an object
  var post_data = querystring.stringify({
      'output_format': 'json',
        'js_code' : codestring
  });
  // An object of options to indicate where to post to
  var post_options = {
      host: '127.0.0.1',
      port: '80',
      path: '/NodeJS/chat_system/php_system.php',
      method: 'POST',
        headers: {
            'Content-Type': 'application/x-www-form-urlencoded',
            'Content-Length': post_data.length
        }
  };
  // Set up the request
  var post_req = http.request(post_options, function(res) {
      res.setEncoding(ENCODING);
      res.on('data', function (chunk) {
          console.log('Response FROM PHP: ' + chunk);
          if (typeof callback == 'function') {
            callback(chunk);
          }
      });
  });
  // post the data
  post_req.write(post_data);
  post_req.end();
}

这是我的PHP服务器

require 'Predis/Autoloader.php';
Predis'Autoloader::register();

function pushToRedis($data) {
    try {
        $redis = new Predis'Client(array(
            'scheme' => 'tcp',
            'host'   => '127.0.0.1',
            'port'   => 6379,
        ));       
    } catch (Exception $e) {
        echo "Couldn't connected to Redis";
        echo $e->getMessage();
        return false;
    }
    $json = json_encode($data);
    $redis->publish("chat", $json);
    return true;
}

pushToRedis('PHP PUSH TO REDIS!');
header('Content-Type: application/json');
echo json_encode(array('response' => print_r(array($_REQUEST, $_SERVER), true)));

而我的客户:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>WebSockets - Simple chat</title>
<style>
    .chat { width: 400px; height: 250px; overflow-y: scroll; }
</style>
</head>
<body>

<script src="http://code.jquery.com/jquery-1.10.1.min.js"></script>
<script>
    var connection = new WebSocket('ws://127.0.0.1:8888');
    $(document).ready(function() {
        /*
        var socket = io.connect('http://127.0.0.1:8888');
        socket.on('message', function (data) {
          alert(data);
        });
        socket.send('HELLO!');
        */

        connection.onopen = function () {
            console.log('connected!');
        };
        connection.onerror = function (error) {
        };  
        connection.onmessage = function (message) {
            $('.chat').append(message.data + '<br>');
            $('.chat').scrollTop($('.chat')[0].scrollHeight);
        };
        $('input[name="text"]').on('keydown', function(e) {
            if (e.keyCode === 13) {
                var msg = $(this).val();
                connection.send(msg);
                $(this).val('').focus();
            }
        });


    });

</script>

<div class="chat">
</div>
<input type="text" name="text">
</body>
</html>

问题是当网络繁忙时,PHP 通过 Redis 将响应返回给 NodeJS 的顺序。

例如:我从 de javascript 客户端发送更多的消息,然后,NodeJS 调用 PHP 每条消息,PHP 将数据保存在 MYSQL 中,并调用 Redis,NodeJS 检测 Redis 推送并更新客户端。但是,在某些情况下,如果我从 Javascript 客户端循环发送一些消息(for(0-10000)),我不会以相同的顺序回复其他客户端,在客户端中获得 200,201,300,202,320,203 这样的数字的情况下。

我认为这是针对 PHP 延迟响应。

我的问题是我如何管理响应以正确的顺序更新客户端? 因为这个问题可能会导致,客户端以错误的顺序接收聊天消息。

但是为什么你想使用php,你可以使用nodejs的mysql包直接将数据发送到mysql

您可以通过以下方式安装 mysql 软件包:npm install mysql

连接方式 :mysql = require('mysql'),

connection = mysql.createConnection({ 主机:"本地主机", 用户:"用户名", 密码:"密码", 数据库:"数据库名称", 端口:3306 }),

并使用以下方法抛出查询:

var q=connection.query('select * from table);