Add a new field to the Typegoose subdocument - mongodb

Question

How do I include an extra field in the User class subdocument?
class Car {
#prop()
public model?: string;
}
class User {
#prop()
public name?: string;
#prop({ required: true })
public age!: number;
#prop({ ref: () => Car })
public cars?: Ref<Car>[];
}
Populated Car Collection:
Car A
{
"_id": "1"
"model": "Ferrari"
}
Car B
{
"_id": "2"
"model": "Tesla"
}
User collection populated according to the default class:
User
{
"_id": "1",
"name": "Jonh Doe",
"age": 25,
"cars": [
{ "_id": "1" },
{ "_id": "2" }
]
}
I need to include a "status" field in the cars array of the User collection, as shown below:
status is to identify whether the car model is active for the user
User
{
"_id": "1",
"name": "Jonh Doe",
"age": 25,
"cars": [
{ "_id": "1", "status": false },
{ "_id": "2", "status": true }
]
}

Answer 1

Hasezoey helped me with the github issue.
Here's the link and his answer.
https://github.com/typegoose/typegoose/discussions/726
You have multiple options:
make the current reference array a subdocumentarray (see example 1)
include the status property on the car itself
have a separate class that has a unique compound index on the user-car references and has the properties you want and have such a reference field in the user (either through virtual populate or with a explicit ref array) (see example 2)
Example 1:
class Car {
#prop()
public model?: string;
}
class UserCarSub {
#prop({ ref: () => Car })
public car: Ref<Car>;
#prop()
public extra_properties: string;
}
class User {
#prop()
public name?: string;
#prop({ required: true })
public age!: number;
#prop()
public cars?: UserCarSub[];
}
Example 2:
// the first example does not use virtual populate
class Car {
#prop()
public model?: string;
}
class UserCarProperties {
#prop({ ref: () => Car })
public car: Ref<Car>;
#prop({ ref: () => User })
public user: Ref<User>;
#prop()
public extra_properties: string;
}
class User {
#prop()
public name?: string;
#prop({ required: true })
public age!: number;
#prop({ ref: () => Car })
public cars?: Ref<Car>[];
#prop({ ref: () => UserCarProperties })
public car_properties: Ref<UserCarProperties>[];
}
// the following uses virtual populate
class User {
#prop()
public name?: string;
#prop({ required: true })
public age!: number;
#prop({ ref: () => Car })
public cars?: Ref<Car>[];
#prop({ ref: () => UserCarProperties, foreignField: 'user', localField: '_id' })
public car_properties: Ref<UserCarProperties>[]; // this property does not exist in the database, but can still populate
}
Virtual Populate
Alternatively you could also in Example 2 merge the cars references into the UserCarProperties and use that to find cars, that is fully up to how you want it
Personally i would suggest Example 2 with virtual populate (merged) if the array is of unknown length or could grow to unknown length