Node.js 使用MongoDB/NodeJS，如何增加更新查询中修改的文档数量？

我在MongoDB/NodeJS中编写了一个更新查询，根据我定义的参数从文档数组中删除对象。拉取这些对象后，我想根据更新查询修改的文档数量，增加文档中的另一个变量

以下是我的活动文档之一的示例：

{
        "_id" : ObjectId("575ed7fca7b89bb4027dded9"),
        "dateCreated" : "6/13/2016",
        "latitude" : "56.294786195890076",
        "longitude" : "-43.59161567687988",
        "instructorName" : "Test User",
        "instructorEmail" : "test@user.com",
        "instructorRating" : 5,
        "eventName" : "We gon exercise",
        "eventDescription" : "We gon exercise",
        "spacesAvailable" : 15,
        "streetAddress" : "123 wer",
        "city" : "rty",
        "state" : "NY",
        "zip" : "12332",
        "date" : "06/21/2016",
        "startTime" : "12:00",
        "endTime" : "02:10",
        "tags" : [
                "Cardio",
                "Crossfit"
        ],
        "price" : 5,
        "attendies" : [
                {
                        "_id" : ObjectId("5759cfcdb71d80fb2d1203ef"),
                        "name" : "Buddy Loester",
                        "email" : "Bud18@gmail.com",
                        "timeStamp" : 1467048318510,
                        "payed" : true
                },
                {
                        "_id" : ObjectId("574f257b05086e2c7f7940ca"),
                        "name" : "Trainer Trainer",
                        "email" : "trainer@user.com",
                        "timeStamp" : 1467055627894,
                        "payed" : true
                }
        ],
        "unpayed" : 0
}

以下是我的代码，以提供更好的可视化效果：

var eventCollection = req.db.get('events');

// get current time since epoch in milliseconds
var milliSinceEpoch = new Date().getTime();

eventCollection.update(
{"attendies.payed" : {$eq : false}},
{
  $pull:
    {
      "attendies" : {"timeStamp": {$lt: milliSinceEpoch /*- 600000*/}}
    }, 
  $inc:
    {
      spacesAvailable: numberAffected
    }
}, 
{
  multi: true
}, function(err, numberAffected) {

    console.log(numberAffected);

    return res.end();

   }
);

如果我在查询部分中将'numberraffected'指定为'1'，那么它将按预期工作并递增1。不过，我想增加受影响的人数

我知道这段代码不能与查询中的'numberraffected'一起使用。在回调中使用'numberraffected'实际上返回了我的查询修改的文档数

---

MongoDB中是否存在一种方法来完成我试图完成的任务？

我通过重写查询解决了我的问题。详情如下:

    var ObjectID = require("mongodb").ObjectID;
    var eventCollection = req.db.get('events');
    var milliSinceEpoch = new Date().getTime(); 

    // find and return all the documents in the events DB where there is a user who has not payed for an event
    // they RSVP'd for
    eventCollection.find({"attendies.payed" : {$eq : false}}, function(err, documentsWithUnpayedUsers) {

        // if error finding, print it and return 
        if(err) {
          console.log(err); 
          return res.sendStatus(400, "Error cancelling");
        }

        // if everyone has payed for all RSVP'd events
        if(!documentsWithUnpayedUsers) return res.sendStatus(404, "Everyone has payed!");

        // loop through every document which has people who have not yet payed for RSVP'd events
        for(var i = 0; i < documentsWithUnpayedUsers.length; i++) {

          // for each of these documents: 
          eventCollection.update(
            {_id: ObjectID(documentsWithUnpayedUsers[i]._id)},
            {
              // remove the user from the attendie list if they have not payed, 
              // and it has been 10 minutes since they RSVP'd
              $pull:
                {
                  "attendies" : {"timeStamp": {$lt: milliSinceEpoch - 600000}, "payed" : {$eq : false}}
                },
              // then modify the number of spaces available for the event by the number of people who were 
              // removed from the attendie list
              // then modify the amount of people who have not payed for the event yet (will now be 0)
              $inc:
                {
                  spacesAvailable: documentsWithUnpayedUsers[i].unpayed,
                  unpayed: -documentsWithUnpayedUsers[i].unpayed
                }
            }, function(err) {
                 // error checking for the update query
                 if(err){
                   console.log(err); 
                   return res.sendStatus(400, "There was an error removing an attendie fom the event: " 
                    + documentsWithUnpayedUsers[i].eventName);
                 }
               }
          ); // end of update query
        } // end of for loop

        return res.end();

       }
    ); // end of find()
  }); // end of checkPayed

var ObjectID=require（“mongodb”）.ObjectID；
var eventCollection=req.db.get（'events'）；
var milliSinceEpoch=new Date（）.getTime（）；
//查找并返回事件数据库中的所有文档，其中有一个用户尚未为事件付款
//他们拒绝了
eventCollection.find（{“attendies.payed”）{$eq:false}，函数（err，documentsWithUnpayedUsers）{
//如果发现错误，请打印并返回
如果（错误）{
控制台日志（err）；
返回res.sendStatus（400，“错误取消”）；
}
//如果每个人都为所有RSVP的活动付费
如果（！documentsWithUnpayedUsers）返回res.sendStatus（404，“每个人都已付款！”）；
//循环浏览每个文档，其中包含尚未为RSVP事件付款的人员
对于（var i=0；i

我通过重写查询解决了问题。详情如下:

    var ObjectID = require("mongodb").ObjectID;
    var eventCollection = req.db.get('events');
    var milliSinceEpoch = new Date().getTime(); 

    // find and return all the documents in the events DB where there is a user who has not payed for an event
    // they RSVP'd for
    eventCollection.find({"attendies.payed" : {$eq : false}}, function(err, documentsWithUnpayedUsers) {

        // if error finding, print it and return 
        if(err) {
          console.log(err); 
          return res.sendStatus(400, "Error cancelling");
        }

        // if everyone has payed for all RSVP'd events
        if(!documentsWithUnpayedUsers) return res.sendStatus(404, "Everyone has payed!");

        // loop through every document which has people who have not yet payed for RSVP'd events
        for(var i = 0; i < documentsWithUnpayedUsers.length; i++) {

          // for each of these documents: 
          eventCollection.update(
            {_id: ObjectID(documentsWithUnpayedUsers[i]._id)},
            {
              // remove the user from the attendie list if they have not payed, 
              // and it has been 10 minutes since they RSVP'd
              $pull:
                {
                  "attendies" : {"timeStamp": {$lt: milliSinceEpoch - 600000}, "payed" : {$eq : false}}
                },
              // then modify the number of spaces available for the event by the number of people who were 
              // removed from the attendie list
              // then modify the amount of people who have not payed for the event yet (will now be 0)
              $inc:
                {
                  spacesAvailable: documentsWithUnpayedUsers[i].unpayed,
                  unpayed: -documentsWithUnpayedUsers[i].unpayed
                }
            }, function(err) {
                 // error checking for the update query
                 if(err){
                   console.log(err); 
                   return res.sendStatus(400, "There was an error removing an attendie fom the event: " 
                    + documentsWithUnpayedUsers[i].eventName);
                 }
               }
          ); // end of update query
        } // end of for loop

        return res.end();

       }
    ); // end of find()
  }); // end of checkPayed

var ObjectID=require（“mongodb”）.ObjectID；
var eventCollection=req.db.get（'events'）；
var milliSinceEpoch=new Date（）.getTime（）；
//查找并返回事件数据库中的所有文档，其中有一个用户尚未为事件付款
//他们拒绝了
eventCollection.find（{“attendies.payed”）{$eq:false}，函数（err，documentsWithUnpayedUsers）{
//如果发现错误，请打印并返回
如果（错误）{
控制台日志（err）；
返回res.sendStatus（400，“错误取消”）；
}
//如果每个人都为所有RSVP的活动付费
如果（！documentsWithUnpayedUsers）返回res.sendStatus（404，“每个人都已付款！”）；
//循环浏览每个文档，其中包含尚未为RSVP事件付款的人员
对于（var i=0；i