Rails 5保存多态关联父窗体

Question

This is driving me crazy!!! I want to save in Rails 5 a polymorphic object within the parent object form, and I can't find a way.

I have a model Contact and it can have multiple polymorphic addresses, but I can't find a way to save an address on the parent creation form.

These are my models:

class Contact < ApplicationRecord
  has_many :addresses, as: :addressable
  accepts_nested_attributes_for :addresses
end

class Address < ApplicationRecord
  belongs_to :addressable, polymorphic: true
end

I would like to let the user to create just one address when he creates a new contact. I am building addresses on ContactsController#new

class ContactsController < ApplicationController

  def new
    @contact = Contact.new
    @contact.addresses.build
  end

  def create
    @contact = Contact.new(contact_params)

    if @contact.save
      redirect_to contacts_path
    else
      render :action => 'new'
    end
  end

  private

  def contact_params
     params.require(:contact).permit(
       :name, :email, :mobile,
       addresses_attributes: [:country, :state, :city, :street, :code])
  end
end

And create a nested form:

<%= form_for @contact do |f| %>
  <%= f.text_field :name %>
  <%= f.text_field :mobile %>
  <%= f.text_field :email %>

  <%= f.fields_for :addresses do |a| %>
    <%= a.text_field :country %>
    <%= a.text_field :state %>
    <%= a.text_field :city %>
    <%= a.text_field :postal_code %>
    <%= a.text_field :street %>
  <% end %>

  <%= f.submit 'Create Contact' %>
<% end %>

It does not work. When I save the form I get an error:

#<ActiveModel::Errors:0x007faac415a768 @base=#<Contact id: nil, 
 name: "John Doe", email: "john@doe.com", mobile: "666666666", 
 created_at: nil, updated_at: nil>, 
@messages={:"addresses.addressable"=>["must exist"]}, 
@details={:"addresses.addressable"=>[{:error=>:blank}]}>

Anyone has an idea what I am doing wrong?

Answer 1

This "solves" the problem, but it is terrible to do it this way:

def create
  @contact = Contact.new(contact_params)
  @contact.addresses.last.addressable = @contact

  if @contact.save
    redirect_to contacts_path
  else
    render :action => 'new'
  end
end