rails4 fail creating relation can't write unknown attribute

Question

I have the following code

db:

create_table :parties do |t|
    t.integer :host_id
    t.integer :guests
    t.string  :description
end

user:

class User < ActiveRecord::Base

  has_many :host_parties, class_name: 'Party'

end

party:

class Party < ActiveRecord::Base
    belongs_to :host, class_name: 'User', foreign_key: 'host_id'

    attr_accessor :user_id
end

parties_controller:

class PartiesController < ApplicationController

    def create
        @party = current_user.host_parties.create(party_params)
    end

    private
    def party_params
      params.require(:party).permit(:host_id, :guests, :description)
    end
 end

for some reason the create fails with:can't write unknown attribute `user_id'

how can I make rails treat the User.id as host_id?

Answer 1

In has_many relationship within your User model, you need to specify the foreign_key as the default value is user_id.

The following should work:

class User < ActiveRecord::Base
  has_many :host_parties, class_name: Party, foreign_key: :host_id
end