Relationships

Model support relationships to other models using One To One or One To Many. Relationships will be automatically mapped as well when creating model or updating its values.

The relationships can de defined using a decorator, see examples below.

One To One

A one-to-one relationship is a very basic type of relationship. For example, a User model might be associated with one Role model.

import { Model, hasOne } from '@outloud/model'

class Role {
  declare id: string
  declare name: string
  declare isAdmin: boolean
}

class User {
  declare id: string
  declare email: string

  @hasOne(() => Role)
  declare role: Role
}

Nullable or optional types are supported as well.

class User {
  declare id: string
  declare email: string

  @hasOne(() => Role)
  declare role?: Role | null
}

When you create model, it will automatically create relationships as well.

// create model
const user = User.create({
  id: '1',
  email: 'test@test.com',
  role: {
    id: '2'
  }
})

user.role // instanceof Role

One To Many

A one-to-many relationship is used to define relationships where a single model is the parent to one or more child models. For example, a blog post may have an infinite number of comments.

import { Model, hasMany } from '@outloud/model'

class Comment {
  declare id: string
  declare text: string
  declare userId: string
}

class Post {
  declare id: string
  declare title: string
  declare userId: string

  @hasMany(() => Comment)
  declare comments: Comment[]
}

When creating array of models the Array's constructor is preserved.

class CustomArray extends Array {
  get first() {
    return this.at(0)
  }
}

class Post {
  declare id: string
  declare title: string

  @hasMany(() => Comment)
  declare comments = new CustomArray<Comment>()
}