Lucid models relationships

models.js

const Model = use('Model')

class User extends Model {
  posts () {
    return this.hasMany('App/Models/Post')
  }
}

class Post extends Model {
  author () {
    return this.belongsTo('App/Models/User')
  }

  categories () {
    return this.belongsToMany('App/Models/Category')
  }
}

class Category extends Model {
  posts () {
    return this.belongsToMany('App/Models/Post')
  }
}