Question

数据模型

var mongoose = require('mongoose');
var Casenote = mongoose.model('Casenote');

var InvoiceSchema = new mongoose.Schema({
  start_date: {type: Date},
  end_date: {type: Date},
  created_on: {type: Date, default: Date.now},
  invoice_num: String,
  month: String,
  type: String,
  provider_num: String,
  rate_280: Number,
  rate_285: Number,
  rate_286: Number,
  rate_287: Number,
  rate_288: Number,
  rate_290: Number,
  qty_280: String,
  qty_285: String,
  qty_286: String,
  qty_287: String,
  qty_288: String,
  qty_290: String,
  total_280: Number,
  total_285: Number,
  total_286: Number,
  total_287: Number,
  total_288: Number,
  total_290: Number
});

InvoiceSchema.pre('save', function(next) {

Casenote.aggregate([
    {
      $match: {
      "created_on": {"$gte": new Date(this.start_date)},
      "created_on": {"$lte": new Date(this.end_date)}
      }
    },
    {
      $group: {
        _id: "$pov",
        count: {$sum: 1}
      }
    }
  ], function(err, data) {
    console.log(data);
  });

  next();
});

mongoose.model('Invoice', InvoiceSchema);

console.log(data)会返回正确的信息。

我想要做的是在save文档上运行InvoiceSchema之前访问数据以配置预配置数据。

在聚合回调中，this引用全局节点对象，而不是InvoiceSchema实例。

如何访问聚合返回的信息并将其设置在引用this实例的InvoiceSchema上？

我想在回调中做什么的例子：

data.map(function(doc) {
    if(doc._id === 280) {
       this.qty_280 = doc.count;
       this.total_280 = doc.count * this.rate_280;
    }
}

Answer 1

我希望聚合回调中的上下文发生变化，试试这个[更新]。

InvoiceSchema.pre('save', function(next) {
    var self = this;
    Casenote.aggregate([
    {
      $match: {
      "created_on": {"$gte": new Date(this.start_date)},
      "created_on": {"$lte": new Date(this.end_date)}
      }
    },
    {
      $group: {
        _id: "$pov",
        count: {$sum: 1}
      }
    }
     ], function(err, data) {
      console.log(data, 'self has the invoice schema', self);
      data.map(function(doc) {
        if(doc._id === 280) {
          self.qty_280 = doc.count;
          self.total_280 = doc.count * self.rate_280;
        }
      });
        next();
    });
});

Mongoose中间件预先聚合数据，然后使用该数据来保存文档

1 个答案: