How to add timestamps fields and _id into nested schema by default - mongodb

Question

I have a correct schema User where fields _id, createdAt, updatedAt are written by default. But in schema Message it doesn't work.
export type UserDocument = HydratedDocument<User>;
#Schema({ timestamps: true, versionKey: false })
export class Message {
#Prop()
content: string;
}
#Schema({ timestamps: true, versionKey: false })
export class User implements UserInterface {
#Prop()
name: string;
#Prop()
email: string;
#Prop([{ type: mongoose.Schema.Types.ObjectId, ref: 'Message' }])
messages?: Message[];
}
export const UserSchema = SchemaFactory.createForClass(User);
Here is my function of message creating:
async createMessage() {
const user = await this.userModel.findById('63ee4fc044d93a4f6bebf934');
user.messages.push({ content: 'a' });
return await user.save();
}
And error is:
Cast to ObjectId failed for value "{ content: 'a' }" (type Object) at path "messages" because of "BSONTypeError"
But this snippet works fine:
async createUser(createUserDto: CreateUserDto): Promise<CreatedUserDto> {
return this.userModel.findOneAndUpdate(
{ name: createUserDto.name },
createUserDto,
{ upsert: true, new: true },
);
}
How to fix it?

Answer 1

Fixed id, correct implementation:
import { Prop, Schema, SchemaFactory } from '#nestjs/mongoose';
import { HydratedDocument } from 'mongoose';
import { UserInterface } from '../interface/user.interface';
export type UserDocument = HydratedDocument<User>;
#Schema({ timestamps: true, versionKey: false })
export class Message {
#Prop()
content: string;
}
export const MessageSchema = SchemaFactory.createForClass(Message);
#Schema({ timestamps: true, versionKey: false })
export class User implements UserInterface {
#Prop()
name: string;
#Prop()
email: string;
#Prop({ type: [MessageSchema], default: [] })
messages?: Message[];
}
export const UserSchema = SchemaFactory.createForClass(User);