express.js controller demo , just for fun !

controller.js

var Controller = function(route){
    this.baseRoute = route;
};
Controller.prototype = {
    actions: {},
    filters: [],
    baseRoute: '',
    _beforeAction:function(){
        var self = this;
        return function(req, res, next){
            try{
                var pass = true;
                var action = self._actionName(req);
                if(!self.actions[action]) {
                    throw new Error('404: action not found');
                }
                for(var i=0;i<self.filters.length;i++){
                    var f = self.filters[i];
                    if(f.actions.indexOf(action) != -1){
                        if(f.check) pass = f.check.call(self, req, res);
                        if(!pass) {
                            throw new Error(f.message || "500: not allowed");
                        }
                    }
                }
                next();
            }catch(e){
                next(e)
            }
        };
    },
    run: function(app,path){
        var self = this;
        if(path) this.baseRoute = path;
        app.all(this.baseRoute +"/(:action)?/?",  self._beforeAction(), function(req, res, next){
            var exists_action = self._getAction(req);
            exists_action(req, res);
        });
    },
    _getAction: function(req){
        var action = this._actionName(req);
        return this.actions[action];
    },
    _actionName: function(req){
        var action = req.params.action;
        var method = req.method.toLowerCase();
        if(!action){ action = 'index'; }
        if(this.actions[action+'_'+method]){
            return action+'_'+method;
        }
        return action;
    }
    
};

// *用法* //

//实例一个controller，默认路由到actions.index
var handle = new Controller('/page');
//向实例里添加动作
handle.actions.index = function(req, res){
    res.send('index !!!')
};
//后缀是 _ + req.method.toLowerCase(), 覆盖普通的index
handle.actions.index_post= function(req, res){
    res.send('post to index !!!')
};
//简陋的过滤器
handle.filters.push({
    actions: ['index'],//要过滤的action列表
    //check为过滤函数，心脏病法，遇到false就不再继续
    //通过返回true，不通过返回false，也可以做redirect等其它动作
    check: function(req, res){ 
      return !!req.query.logged
    },
    //false时提供的错误信息
    message:'Not logged in!'
});

exports = module.exports = handle