Mongodb Populate is not populating document in Node.js-CodePudding

I am using typegoose and my Query and QueryRule models are as below.

export class Query {
  @prop()
  queryRule: Ref<QueryRule>;
}

export class QueryRule {
  @prop()
  condition: Condition;

  @prop()
  rules: Ref<QueryRule | ChildRule>[];
}

I am using the following query to populate.

await QueryModel.findById(queryId).populate('queryRule');

My Query Document is as below.

{"_id":{"$oid":"6283d73baffa60c38af8c2f0"},"name":"test","queryRule":{"$oid":"6287c8f0e3ab4b5dd7238ef3"}}

My QueryRule Document is as below.

{"_id":{"$oid":"6287c8f0e3ab4b5dd7238ef3"},"condition":1,"rules":[],"__v":0}

But when I access condition and rules of QueryRule using populate query. I am getting undefined even though values exist in that document.

What am I doing wrong here?

CodePudding user response：

@prop({
  ref: () => QueryRule | ChildRule,
  required: true
})
rules: Ref<QueryRule | ChildRule>[];

CodePudding user response：

Your issue seems to be that you are missing the required option ref, see Reference other Classes from the Typegoose Documentation.

In your case your code should look more like:

export class Query {
  @prop({ ref: () => QueryRule })
  queryRule: Ref<QueryRule>;
}

export class QueryRule {
  @prop()
  condition: Condition;

  //@prop({ ref: () => QueryRule })
  //rules: Ref<QueryRule | ChildRule>[];
}

As for Ref<QueryRule | ChildRule>[], you will either have to limit it to one on the 2 possibilities or use discriminators, see Non-Nested Discriminators from the Typegoose Documentation.

Also as a small side-note, if your condition: Condition is not also a typegoose class, it will become Mixed, which is basically a any type at runtime in mongoose.