Mongoose.js虚拟填充

Question

我的项目中有一个圆形模型：

var circleSchema = new Schema({
//circleId: {type: String, unique: true, required: true},
patientID: {type: Schema.Types.ObjectId, ref: "patient"},
circleName: String,
caregivers: [{type: Schema.Types.ObjectId}],
accessLevel: Schema.Types.Mixed
});

circleSchema.virtual('caregiver_details',{
    ref: 'caregiver',
    localField: 'caregivers',
    foreignField: 'userId'
});

照顾者模式：

var cargiverSchema = new Schema({
    userId: {type: Schema.ObjectId, unique: true},  //objectId of user document
    detailId: {type: Schema.ObjectId, ref: "contactDetails"},
    facialId: {type: Schema.ObjectId, ref: "facialLibrary"}, //single image will be enough when using AWS rekognition
    circleId: [{type: Schema.Types.ObjectId, ref: "circle"}],           //multiple circles can be present array of object id
});

样本对象：

{ 
    "_id" : ObjectId("58cf4832a96e0e3d9cec6918"), 
    "patientID" : ObjectId("58fea8ce91f54540c4afa3b4"), 
    "circleName" : "circle1", 
    "caregivers" : [
        ObjectId("58fea81791f54540c4afa3b3"), 
        ObjectId("58fea7ca91f54540c4afa3b2")
    ], 
    "accessLevel" : {
        "location\"" : true, 
        "notes" : false, 
        "vitals" : true
    }
}

我已经尝试过为mongoosejs进行虚拟填充，但是无法使其正常工作。这似乎是完全相同的问题：https
:
//github.com/Automattic/mongoose/issues/4585

circle.find({"patientID": req.user._id}).populate('caregivers').exec(function(err, items){
        if(err){console.log(err); return next(err) }
        res.json(200,items);
    });

我只得到结果中的对象ID。它没有被填充。

Answer 1

找出问题所在。默认情况下，虚拟字段不包含在输出中。在圈子模式中添加以下内容之后：

circleSchema.virtual('caregiver_details',{
    ref: 'caregiver',
    localField: 'caregivers',
    foreignField: 'userId'
});

circleSchema.set('toObject', { virtuals: true });
circleSchema.set('toJSON', { virtuals: true });

现在，它可以完美运行。