如何根据参考/模型填充字段？

Question

我有两个用户模式：

UserSchema1 = new mongoose.Schema({
    firstName:{
        type: String
    }
})

UserSchema2 = new mongoose.Schema({
    email:{
        type: String
    }
})


ChatMessageSchema = new mongoose.Schema({
        senderId:{
            type: mongoose.Schema.Types.ObjectId,
            refPath: 'onModel',
            required: true
        },
        onModel:{
            type: String,
            required: true,
            enum: ['userSchema1', 'userSchema2']
        },
        message: {
            type: String,
            required: true
        }
})

现在，我需要填充所有聊天消息。我需要如下结果：

[
    {
        senderId:{
            firstName or email
        },
        onModel: userSchema1 / userSchema2,
        message: "message"
    },
    {

    }, ...
]

也就是说，如果发件人是 UserSchema1，那么它应该填充 firstName，如果它是 UserSchema2，它应该填充电子邮件。我无法填充所有字段，因为每个集合中有 20 多个字段。

简而言之，如果是 UserSchema1，它应该只填充 firstName，如果是 UserSchema2，它应该只填充电子邮件。

Answer 1

我猜您可以使用此架构进行聊天，它比您的架构更好 使用用户 ID 并通过 Id 获取用户数据

   MessageSchema = new mongoose.Schema({
      from: {
        type: string,
        required: true,
      },
      to: {
        type: string,
        required: true,
      },
      time: {
        type: Date,
        default: Date.now(),
      },
      message: {
        type: string,
        required: true,
      },
    });


ChatSchema = new mongoose.Schema({
        firstUserId:{
            type: mongoose.Schema.Types.ObjectId,
            required: true,
        },
        secondUserId:{
            type: mongoose.Schema.Types.ObjectId,
            required: true,
        },
        Chat: MessageSchema,
})

数据会这样

[
  {
    firstUserId: "hjakdsf323275lks",
    secondUserId: "asdfe2342232aas",
    Chat: [
      {
        from: "hjakdsf323275lks",
        to: "asdfe2342232aas",
        time: "18/7/2020 20:06:09",
        message: "Hi ",
      },
      {
        from: "asdfe2342232aas",
        to: "hjakdsf323275lks",
        time: "18/7/2020 21:07:09",
        message: "hello ",
      },....
    ],
  },
];