如何使用来自另一个子文档的数据填充 Mongoose 子文档

Question

我有一个 MongoDB 数据库，其中包含有关足球俱乐部的数据。俱乐部有球员和赛季。一个球员每个赛季可以有不同的球队号码。

考虑以下 Mongoose 架构：

const clubSchema = new mongoose.Schema({
    players: [playerSchema],
    seasons: [seasonSchema]
});

const personSchema = new mongoose.Schema({
    firstName: String,
    lastName: String
});

const playerSchema = new mongoose.Schema({
    person: personSchema,
    picture: String
});

const seasonSchema = new mongoose.Schema({
    name: String,
    seasonPlayers: [seasonPlayerSchema]
});

const seasonPlayerSchema = new mongoose.Schema({
    player: {
        type: mongoose.Schema.Types.ObjectId,
        ref: "Player"
    },
    squadNumber: Number
});

如何检索完全填充的Club 文档？所以不要得到这样的东西：

{
  players: [
    {
      _id: ObjectId("abc123"),
      person: {
        firstName: "John",
        lastName: "Doe"
      }
      picture: "john.jpg"
    }
  ],
  seasons: [
    name: "2015-2016",
    seasonPlayers: [
      {
        player: ObjectId("abc123"),
        squadNumber: 10
      }
    ]
  ]
}

我想要这样的东西：

{
  players: [
    {
      _id: ObjectId("abc123"),
      person: {
        firstName: "John",
        lastName: "Doe"
      }
      picture: "john.jpg"
    }
  ],
  seasons: [
    name: "2015-2016",
    seasonPlayers: [
      {
        player: {
          person: {
            firstName: "John",
            lastName: "Doe"
          }
          picture: "john.jpg"
        },
        squadNumber: 10
      }
    ]
  ]
}

Answer 1

您可以在 Mongoose 的 population 路径中使用点表示法来指定要填充的子文档层次结构中的路径：

Club.findOne().populate('seasons.seasonPlayers.player').exec(function(err, club) {...});