NestJS mongose schema with array of schema doesn't populate virtual id - node.js

Question

I have the following schema
export type MapDocument = Map & Document
#Schema({
timestamps: true,
versionKey: false,
id: true
})
export class Map {
constructor(partial?: Partial<Map>) {
if (partial)
Object.assign(this, partial)
}
#IsOptional()
#IsUUID()
#Prop({ type: Object, default: uuidv4, required: false})
#Exclude({ toPlainOnly: true })
_id?: Object
#ApiPropertyOptional({ type: String, format: 'uuid' })
#IsOptional()
#IsUUID()
id?: string
#ApiProperty()
#IsAscii()
#MaxLength(10)
#Prop()
building: string
#ApiProperty()
#IsInt()
#Prop()
#Transform(({ value }) => +value, { toClassOnly: true })
floor: number
#ApiPropertyOptional({ type: Image, format: 'uuid'})
#IsOptional()
#IsUUID()
#Prop({ type: String, ref: 'Image' })
#Transform(({ value }) => new Image(value).id, { toClassOnly: true })
image?: string
#ApiProperty({ type: [Marker] })
#IsArray()
#Type(() => Marker)
#Prop({ type: [MarkerSchema] })
markers?: Marker[]
}
const MapSchema = SchemaFactory.createForClass(Map)
MapSchema.index({ building: 1, floor: 1 }, { unique: true });
const mongooseLeanVirtuals = require('mongoose-lean-virtuals')
MapSchema.plugin(mongooseLeanVirtuals);
export { MapSchema }
export class UpdateMap extends PartialType(Map) {}
Marker is declared as follows
export type MarkerDocument = Marker & Document
#Schema({
timestamps: true,
versionKey: false,
id: true
})
export class Marker {
constructor(partial?: Partial<Marker>) {
if (partial)
Object.assign(this, partial)
}
#IsOptional()
#IsUUID()
#Prop({ type: Object, default: uuidv4, required: false})
#Exclude({ toPlainOnly: true })
_id?: Object
#ApiPropertyOptional({ type: String, format: 'uuid' })
#IsOptional()
#IsUUID()
id?: string
#ApiPropertyOptional({ type: Desk, format: 'uuid'})
#IsOptional()
#IsUUID()
#Prop({ type: String, required: false, ref: 'Desk' })
#Transform(({ value }) => new Desk(value).id, { toClassOnly: true })
desk?: string
#ApiProperty()
#IsNumberString()
#Prop()
xPercent: string
#ApiProperty()
#IsNumberString()
#Prop()
yPercent: string
}
const MarkerSchema = SchemaFactory.createForClass(Marker)
const mongooseLeanVirtuals = require('mongoose-lean-virtuals')
MarkerSchema.plugin(mongooseLeanVirtuals);
export { MarkerSchema }
export class UpdateMarker extends PartialType(Marker) {}
Important to note that has a field (desk) referencing another collection but I don't want these items to be stored in their own collection but as a subdocument of the 'maps' collection directly
The 'desk' schema is declared as follows
export type DeskDocument = Desk & Document
#Schema({
timestamps: true,
versionKey: false,
id: true
})
#ApiExtraModels(Image)
export class Desk {
constructor(partial?: Partial<Desk>) {
if (partial)
Object.assign(this, partial)
}
#IsOptional()
#IsUUID()
#Prop({ type: Object, default: uuidv4, required: false})
#Exclude({ toPlainOnly: true })
_id?: Object
#ApiPropertyOptional({ type: String, format: 'uuid' })
#IsOptional()
#IsUUID()
id?: string
#ApiProperty({ type: Board, format: 'uuid'})
#IsUUID('all')
#Prop({ type: String, required: true, ref: 'Board' })
#Transform(({ value }) => value.id, { toClassOnly: true })
board: string
#ApiProperty({ type: [Number] })
#IsArray()
#Prop({ type: () => [Number], required: true })
relays?: number[]
#ApiProperty()
#IsAscii()
#MaxLength(250)
#Prop()
name: string
#ApiProperty()
#IsAscii()
#MaxLength(250)
#Prop()
description: string
#ApiProperty()
#IsAscii()
#MaxLength(10)
#Prop()
building: string
#ApiProperty()
#IsInt()
#Prop()
#Transform(({ value }) => +value, { toClassOnly: true })
floor: number
#ApiProperty()
#IsAscii()
#MaxLength(10)
#Prop()
code: string
#ApiPropertyOptional({ type: [Image], format: 'uuid'})
#IsOptional()
#IsUUID('all', { each: true })
#Prop({ type: [String], required: false, ref: 'Image' })
#Transform(({ value }) => value.id, { toClassOnly: true })
images?: String[]
}
const DeskSchema = SchemaFactory.createForClass(Desk)
DeskSchema.index({ board: 1, relays: 1 }, { unique: true });
const mongooseLeanVirtuals = require('mongoose-lean-virtuals')
DeskSchema.plugin(mongooseLeanVirtuals)
export { DeskSchema }
export class UpdateDesk extends PartialType(Desk) {}
The find methods tried to populate everything down to desk (no need for me to populate deeper than that)
async findAll(): Promise<Map[]> {
return (await this.mapModel.find().populate({
path: 'image',
model: Image,
transform: (doc: Image) => new Image(doc),
}).populate({
path: 'markers',
model: Marker,
transform: (doc: Marker) => new Marker(doc),
populate: {
path: 'desk',
model: Desk,
transform: (doc: Desk) => new Desk(doc),
options: { lean: true, virtuals: true },
}
}).lean({ virtuals: true }).exec())
.map(map => new Map(map))
}
Two issues
Minor: If I don't specify lean: true as an option for the desk populate I get the full mongo document. This is not the case for the 'markers' array which relies on the 'lean' settings
Main: the desk object gets populated but the virtual 'id' field doesn't
This is the output I get:
{
"building": "A",
"floor": 1,
"image": {
"name": "OfficePlan12",
"url": "https://drive.google.com/uc?id=1H2nnIRjR2e7Z7yoVnHxLCTaYs8s5iHrT",
"updatedAt": "2022-06-24T09:03:03.786Z",
"id": "2b31f419-e069-4058-813e-54ce0a941440"
},
"updatedAt": "2022-06-26T10:19:22.650Z",
"markers": [
{
"yPercent": "15.853658536585366",
"xPercent": "18.083462132921174",
"desk": {
"images": [
"b85eefee-eeca-4193-87ae-9329fad8256a",
"692743d0-a860-4451-b313-b21a144ef387"
],
"description": "Work like a boss",
"name": "Management desk",
"createdAt": "2022-02-19T21:12:18.832Z",
"updatedAt": "2022-06-07T14:02:13.556Z",
"building": "A",
"code": "01",
"floor": 1,
"relays": [
"1"
],
"board": "932c3e9b-85bd-42c8-9bc0-a318eea7b036"
},
"updatedAt": "2022-06-26T10:19:22.650Z",
"createdAt": "2022-06-26T10:19:22.650Z",
"id": "a8149e84-2f62-46c3-990f-531eff82f6d5"
}
],
"id": "37dc791f-724b-44e2-baaf-bfc606385996"
}
As you can see the 'desk' object doesn't have 'id' field.
Any help would be much appreciated, thanks!

Answer 1

I finally found a workaround.
It looks pretty bad to be fair but it does the trick.
Basically I modified the transform function for the 'desk' document which is the first 'outer' document of my 'inner' document 'image'.
The function looks as follows:
transform: (doc: Desk) => new Desk((new this.deskModel(doc)).toObject({ virtuals: true })),
options: { lean: true },
populate: {
path: 'images',
model: Image,
transform: (doc: Image) => new Image(doc)
}
Basically I needed to inject the corresponding model in the service constructor to be able to call the 'toObject' function with 'options' and 'populate'. Finally I need to use the obtained object to build a new instance of 'Desk' to make sure that class validation functions are applied correctly to my endpoints.
Hope this will help someone and that maybe someone can suggest a more elegant solution.