使用mongoosejs缩小地图

Question

我想要使用Nodejs，mongoose和MongoDB来减少地图操作。 我有一个相当平坦的模式结构，我想获得每个'named'对象的值/日期对列表。地图缩小功能显然有些问题，但我看不到如何修复它以获取我之后的格式。

MongoDB的文档架构如下：

{ "name" : "object1", "value" : "123", "date" : "2013-01-02 01:00:00" } 
{ "name" : "object1", "value" : "456", "date" : "2013-01-02 02:00:00" } 
{ "name" : "object2", "value" : "123", "date" : "2013-01-02 02:00:00" } 

的地图上减少我用我的猫鼬架构功能如下：

var o = {}; 
o.map = function() { 
    emit(
    { 'name': this.name }, 
    {'data': [ { 'value': this.value, 'date': this.date} ] } 
) 
} 

o.reduce = function (k, vals) { 
    var reduced = {'data': []}; 
    for (var i in vals) { 
    reduced.data.push(vals[i]); 
    } 
    return reduced; 
} 

this.mapReduce(o, function(err, model) { 
    if(err) console.log(err); 
    model.find().exec(cb); 
}); 

我想看到的是一些JSON沿线

[ 
    { 
    "name": "object1", 
    "data": [ 
     { 
     "value": "123", 
     "date": "2013-01-02T01:00:00.123456" 
     }, 
     { 
     "value": "456", 
     "date": "2013-01-02T02:00:00.123456" 
     }, 
    ] 
    }, 
    { 
    "name": "object2", 
    "data": [ 
     { 
     "value": "123", 
     "date": "2013-04-22T13:10:03.893018" 
     }, 
     ... 
    ] 
    }, 
    ... 

但我最终得到了这个嵌套的混乱！有人能给我一个指针，指出我错过了什么！

[ 
    { 
    "_id": { 
     "name": "object1" 
    }, 
    "value": { 
     "data": [ 
     { 
      "data": [ 
      { 
       "data": [ 
       { 
        "data": [ 
        { 
         "value": "123", 
         "date": "2013-01-02T02:00:00.123456" 
        } 
        ] 
       }, 
       { 
        "data": [ 
        { 
         "value": "465", 
         "date": "2013-01-02T01:00:00.123456" 
        } 
        ] 
       }, 
       ... etc 

Answer 1

尝试类似的东西：（未经测试，但这个想法是在这里，我想:)）

var o = {}; 
o.map = function() { 
    emit(this.name, { 'value': this.value, 'date': this.date}) 
} 

o.reduce = function (k, vals) { 
    var reduced = {name: k, data : []}; 
    for (var i in vals) { 
    reduced.data.push(vals[i]); 
    } 
    return reduced; 

    // or just return vals? it's already the array you want. 
}