Javascript 使用Node_redis调用Node.js

我仍在尝试进入node.js，可能有些地方不太对劲。我要做的是首先查询一个包含房间列表的hmap。此列表将通过迭代获得每个房间的详细信息，如房间名称等

以下是查询应返回的内容：

redis 127.0.0.1:6379> lrange rooms 0 -1
1) "room:5000"

及

这是routes.index中的函数

exports.index = function(req, res){

    var render_rooms = new Array();

    req.app.settings.redis.lrange('rooms',0,-1, function(error, rooms) {

        if (error) {
            console.log('Error: '+ error);
            }
        else {

            rooms.forEach(function(room){
                console.log("room: " + room);

                req.app.settings.redis.hgetall(room, function(error, roomdetails){
                    if (error) {
                        console.log('Error: '+ error);
                        }
                    else {
                        console.log("roomdetails: " + roomdetails.public);

                        if(roomdetails.public == "true"){
                            render_rooms.push(roomdetails.name);

                        }

                    }
                });

            });




        //  console.log('Name: ' + result);
      //    res.render('account', { title: 'account title', user: req.user.username, votes: result });
        }

    });


    console.log("length: " + render_rooms.length);
    res.render('index', { title: 'Index', username: req.user.username, rooms: render_rooms });

};

---

我不确定是否正确使用node_redis来实现这一点。此外，我还提出了将所有房间细节存储在一个数组中的想法，我期待着将其发送到视图中。显然，列表总是不显示任何元素，因为我想在填充列表之前会调用这些元素，因为我缺少一些基本的回调功能。但是我不能把它摆弄进去。有人能更详细地解释一下它“应该”是如何工作的吗？

您的基本问题是需要等待渲染

渲染房间

阵列，直到所有异步处理完成。按照现在编写的方式，

res.render

在任何异步Redis查询完成之前被调用

大概是这样的：

exports.index = function(req, res){

    var render_rooms = new Array();

    req.app.settings.redis.lrange('rooms',0,-1, function(error, rooms) {

        // Keep track of the number of rooms we have left to process.
        var roomcount = rooms.length;

        if (error) {
            console.log('Error: '+ error);
            }
        else {

            rooms.forEach(function(room){
                console.log("room: " + room);

                req.app.settings.redis.hgetall(room, function(error, roomdetails){
                    if (error) {
                        console.log('Error: '+ error);
                        }
                    else {
                        console.log("roomdetails: " + roomdetails.public);

                        if(roomdetails.public == "true"){
                            render_rooms.push(roomdetails.name);
                        }

                        // Render code moves to here and is only run after all rooms
                        // have been processed.
                        if (--roomcount === 0) {
                            console.log("length: " + render_rooms.length);
                            res.render('index', { 
                                title: 'Index', 
                                username: req.user.username, 
                                rooms: render_rooms 
                            });
                        }
                    }
                });
            });
        }
    });
};

---

一旦你对这项工作感到满意，就看看如何使用或哪种更干净地支持这种类型的流来清理它。

thx，我希望一些避免计数的方法能够奏效。我还将了解异步。

exports.index = function(req, res){

    var render_rooms = new Array();

    req.app.settings.redis.lrange('rooms',0,-1, function(error, rooms) {

        // Keep track of the number of rooms we have left to process.
        var roomcount = rooms.length;

        if (error) {
            console.log('Error: '+ error);
            }
        else {

            rooms.forEach(function(room){
                console.log("room: " + room);

                req.app.settings.redis.hgetall(room, function(error, roomdetails){
                    if (error) {
                        console.log('Error: '+ error);
                        }
                    else {
                        console.log("roomdetails: " + roomdetails.public);

                        if(roomdetails.public == "true"){
                            render_rooms.push(roomdetails.name);
                        }

                        // Render code moves to here and is only run after all rooms
                        // have been processed.
                        if (--roomcount === 0) {
                            console.log("length: " + render_rooms.length);
                            res.render('index', { 
                                title: 'Index', 
                                username: req.user.username, 
                                rooms: render_rooms 
                            });
                        }
                    }
                });
            });
        }
    });
};