models.ex

defmodule Shop.Order do
  use Shop.Web, :model
  
  schema "orders" do
    field :email, :string
    has_one :address, Shop.Address
    
    timestamps
  end
  
  @required_fields ~w(email)
  @optional_fields ~w(shipping_address)
  
  def changeset(model, params \\ :empty) do
    model |> cast(params, @required_fields, @optional_fields)
  end
end

defmodule Shop.Address do
  use Shop.Web, :model
  
  schema "addresses" do
    field :firstname, :string
    field :lastname, :string
    field :address1, :string
    field :address2, :string
    field :city, :string
    field :postal_code, :string
    field :state_name, :string
    field :phone, :string
    field :country, :string
    belongs_to :order, Shop.Order

    timestamps
  end

  @required_fields ~w(firstname lastname address1 city postal_code state_name country)
  @optional_fields ~w(phone address2)

  def changeset(model, params \\ :empty) do
    model |> cast(params, @required_fields, @optional_fields)
  end
end