javascript - 仅在满足条件时填充

Question

我有一个 mongodb 数据库，我将 mongoose 与 nodejs 结合使用。

仅当我有字段“temtussvinculado=true”时，我才需要从填充“tabela_tuss”的下一个查询返回数据。

这是我正在做的:

ConvProced.find({'convenioId':new ObjectId(req.params.id)})
        .populate('convenioId')
        .populate({
             path:'procedId',
             populate:{
                 path:'tabela_tuss',
                 match: { 'procedId.temtussvinculado': true}
            }
        })
        .exec( (err,data) => {
           callback(err,data,res)
        })

我的问题是我与“procedId.temtussvinculado:true”的匹配没有效果，并且“tabela_tuss”从未被填充。

我做错了什么？

这是我的模式:

////
var conveniosSchema = new mongoose.Schema({
  nome: {type: String, unique:true},
  ativo: {type: Boolean}
 });
module.exports = mongoose.model('Convenio', conveniosSchema,'convenios' );
////

////
const agProcedimentosSchema = new mongoose.Schema({
  ativo:{type:Boolean},
  temtussvinculado:{type:Boolean},
  tabela_tuss:{type:mongoose.Schema.Types.ObjectId, ref:'Tuss_22'}
});
module.exports = mongoose.model('Ag_procedimento', agProcedimentosSchema,'ag_procedimentos' );
///

////
const tuss_22Schema = new mongoose.Schema({
  codigo: {type: String, unique:true},
  descricao:{type: String},
  tabela:{type: String}
});
module.exports = mongoose.model('Tuss_22', tuss_22Schema,'tuss_22' );
////

//../models/convenioprocedimento
var conveniosProcedsSchema = new mongoose.Schema({
   convenioId:{type:mongoose.Schema.Types.ObjectId, ref:'Convenio'},
   procedId:{type:mongoose.Schema.Types.ObjectId, ref:'Ag_procedimento'},
   valor_particular:{type:Number},
   valor_convenio:{type:Number},
  });

module.exports = mongoose.model('ConvenioProcedimento', conveniosProcedsSchema,'conveniosprocedimentos' );

//my query:

const ConvProced = require('../models/convenioprocedimento');
ConvProced.find({'convenioId':new ObjectId(req.params.id)})
    .populate('convenioId')
    .populate({
         path:'procedId',
         populate:{
             path:'tabela_tuss',
             match: { 'procedId.temtussvinculado': true}
        }
    })
    .exec( (err,data) => {
       callback(err,data,res)
    })

Answer 1

您在这里实际要问的是“仅在数据中的条件要求这样做的地方填充”，这实际上并不是.populate() 的“直接”支持操作。或使用“嵌套填充”语法。

因此，如果您想对实际填充或不填充项目施加“条件”，那么您必须“手动”处理填充调用。

您的情况的基本前提是您需要检查需要从“初始”顶层获得的值 .populate()调用，但随后“仅”在给定条件实际允许时调用“内部”填充。

所以你的代码应该看起来像这样使用“Promises”使用 Promise.all()你基本上“循环”或.map()每个查询结果并测试 proceedid.temtussvinculado 以查看它是否为 true/false，而 true 我们实际发出一个 Model.populate()调用，否则只返回当前状态的数据:

ConvProced.find({'convenioId':new ObjectId(req.params.id)})
  .populate('convenioId procedId')
  .exec()
  .then(data =>
    Promise.all(
      data.map( d => 
        ( d.proceedid.temtussvinculado )
        ? mongoose.model('Tuss_22').populate(d,{ path: 'proceedId.tabela_tuss' })
        : d
      )
    )
  )
)
// Populated conditionally
.then( data =>
  // Do something with data
)
.catch(err => console.error(err)); // or something else with error

除了“Promises”之外还有其他可用选项，但它是无依赖选项。其他情况，例如 async.map做同样的事情，但如果你还没有它，那就是一个额外的依赖:

ConvProced.find({'convenioId':new ObjectId(req.params.id)})
  .populate('convenioId procedId')
  .exec((err,data) => {
    if (err) throw err;
    async.map(data,(d,callback) =>
      ( d.proceedid.temtussvinculado )
        ? mongoose.model('Tuss_22').populate(d,{ path: 'proceedId.tabela_tuss' },callback)
        : callback(null,d)
      (err,data) => {
        if (err) throw err; // or something
        // Conditionally populated
      }
    )
  })

还用一个完整的工作示例进行了演示，这实际上比您需要做的要复杂一点，因为在这个示例中“条件”嵌套在另一个数组中:

const async = require('async'),
      mongoose = require('mongoose'),
      Schema = mongoose.Schema;

mongoose.Promise = global.Promise;
mongoose.set('debug',true);

mongoose.connect('mongodb://localhost/test');


const subInnerSchema = new Schema({
  label: String
});

const innerSchema = new Schema({
  name: String,
  populate: Boolean,
  subs: [{ type: Schema.Types.ObjectId, ref: 'Sub' }]
});

const outerSchema = new Schema({
  title: String,
  inners: [{ type: Schema.Types.ObjectId, ref: 'Inner' }]
});

const Sub = mongoose.model('Sub', subInnerSchema);
const Inner = mongoose.model('Inner', innerSchema);
const Outer = mongoose.model('Outer', outerSchema);

function log(data) {
  console.log(JSON.stringify(data, undefined, 2))
}

async.series(
  [
    // Clean data
    (callback) =>
      async.each(mongoose.models,(model,callback) =>
        model.remove({},callback),callback),

    // Insert some data
    (callback) =>
      async.waterfall(
        [
          (callback) =>
            Sub.create([1,2,3,4].map( label => ({ label })),callback),

          (subs,callback) =>
            Inner.create(
              [0,2].map(x => subs.slice(x,x+2))
              .map((el,i) => ({
                name: i+i,
                populate: i == 1,
                subs: el
              })),
              callback
            ),

          (inners,callback) =>
            Outer.create(
              inners.map((inner,i) => ({
                title: i+1,
                inners: [inner]
              })),
              callback
            ),

        ],
        callback
      ),

    // Conditional populate async.map version
    (callback) =>
      Outer.find().populate('inners').exec((err,outers) => {
        if (err) callback(err);

        async.map(
          outers,
          (outer,callback) =>
            async.map(
              outer.inners,
              (inner,callback) =>
                (inner.populate)
                  ? Inner.populate(inner,{ path: 'subs' },callback)
                  : callback(null,inner),

              (err,inners) => {
                if (err) callback(err);
                outer.inners = inners
                callback(null,outer);
              }
            ),

          (err,outers) => {
            if (err) callback(err);
            log(outers);
            callback();
          }
        );
      }),

    // Conditional populate Promise
    (callback) =>
      Outer.find().populate('inners').exec()
        .then(outers =>
          Promise.all(
            outers.map( outer =>
              new Promise((resolve,reject) => {
                Promise.all(
                  outer.inners.map( inner =>
                    (inner.populate)
                      ? Inner.populate(inner,{ path: 'subs' })
                      : inner
                  )
                ).then(inners => {
                  outer.inners = inners;
                  resolve(outer)
                })
                .catch(reject)
              })
            )
          )
        )
        .then(outers => {
          log(outers);
          callback();
        })
        .catch(err => callback(err))


  ],
  (err) => {
    if (err) throw err;
    mongoose.disconnect();
  }
);

这会产生显示“条件”选择的输出，当然可以使用任何一种方法:

Mongoose: subs.remove({}, {})
Mongoose: inners.remove({}, {})
Mongoose: outers.remove({}, {})
Mongoose: subs.insert({ label: '1', _id: ObjectId("5961830256bf9e2d0fcf13b3"), __v: 0 })
Mongoose: subs.insert({ label: '2', _id: ObjectId("5961830256bf9e2d0fcf13b4"), __v: 0 })
Mongoose: subs.insert({ label: '3', _id: ObjectId("5961830256bf9e2d0fcf13b5"), __v: 0 })
Mongoose: subs.insert({ label: '4', _id: ObjectId("5961830256bf9e2d0fcf13b6"), __v: 0 })
Mongoose: inners.insert({ name: '0', populate: false, _id: ObjectId("5961830256bf9e2d0fcf13b7"), subs: [ ObjectId("5961830256bf9e2d0fcf13b3"), ObjectId("5961830256bf9e2d0fcf13b4") ], __v: 0 })
Mongoose: inners.insert({ name: '2', populate: true, _id: ObjectId("5961830256bf9e2d0fcf13b8"), subs: [ ObjectId("5961830256bf9e2d0fcf13b5"), ObjectId("5961830256bf9e2d0fcf13b6") ], __v: 0 })
Mongoose: outers.insert({ title: '1', _id: ObjectId("5961830256bf9e2d0fcf13b9"), inners: [ ObjectId("5961830256bf9e2d0fcf13b7") ], __v: 0 })
Mongoose: outers.insert({ title: '2', _id: ObjectId("5961830256bf9e2d0fcf13ba"), inners: [ ObjectId("5961830256bf9e2d0fcf13b8") ], __v: 0 })
Mongoose: outers.find({}, { fields: {} })
Mongoose: inners.find({ _id: { '$in': [ ObjectId("5961830256bf9e2d0fcf13b7"), ObjectId("5961830256bf9e2d0fcf13b8") ] } }, { fields: {} })
Mongoose: subs.find({ _id: { '$in': [ ObjectId("5961830256bf9e2d0fcf13b5"), ObjectId("5961830256bf9e2d0fcf13b6") ] } }, { fields: {} })
[
  {
    "_id": "5961830256bf9e2d0fcf13b9",
    "title": "1",
    "__v": 0,
    "inners": [
      {
        "_id": "5961830256bf9e2d0fcf13b7",
        "name": "0",
        "populate": false,
        "__v": 0,
        "subs": [
          "5961830256bf9e2d0fcf13b3",
          "5961830256bf9e2d0fcf13b4"
        ]
      }
    ]
  },
  {
    "_id": "5961830256bf9e2d0fcf13ba",
    "title": "2",
    "__v": 0,
    "inners": [
      {
        "_id": "5961830256bf9e2d0fcf13b8",
        "name": "2",
        "populate": true,
        "__v": 0,
        "subs": [
          {
            "_id": "5961830256bf9e2d0fcf13b5",
            "label": "3",
            "__v": 0
          },
          {
            "_id": "5961830256bf9e2d0fcf13b6",
            "label": "4",
            "__v": 0
          }
        ]
      }
    ]
  }
]
Mongoose: outers.find({}, { fields: {} })
Mongoose: inners.find({ _id: { '$in': [ ObjectId("5961830256bf9e2d0fcf13b7"), ObjectId("5961830256bf9e2d0fcf13b8") ] } }, { fields: {} })
Mongoose: subs.find({ _id: { '$in': [ ObjectId("5961830256bf9e2d0fcf13b5"), ObjectId("5961830256bf9e2d0fcf13b6") ] } }, { fields: {} })
[
  {
    "_id": "5961830256bf9e2d0fcf13b9",
    "title": "1",
    "__v": 0,
    "inners": [
      {
        "_id": "5961830256bf9e2d0fcf13b7",
        "name": "0",
        "populate": false,
        "__v": 0,
        "subs": [
          "5961830256bf9e2d0fcf13b3",
          "5961830256bf9e2d0fcf13b4"
        ]
      }
    ]
  },
  {
    "_id": "5961830256bf9e2d0fcf13ba",
    "title": "2",
    "__v": 0,
    "inners": [
      {
        "_id": "5961830256bf9e2d0fcf13b8",
        "name": "2",
        "populate": true,
        "__v": 0,
        "subs": [
          {
            "_id": "5961830256bf9e2d0fcf13b5",
            "label": "3",
            "__v": 0
          },
          {
            "_id": "5961830256bf9e2d0fcf13b6",
            "label": "4",
            "__v": 0
          }
        ]
      }
    ]
  }
]

因此您可以看到，以几乎相同的方式有一个“ bool ”字段正在被测试以确定是执行 .populate() 还是只返回纯数据。