Question

On my server, I have two models:

Broadcast

class Broadcast < ActiveRecord::Base

  validates_presence_of :content

  belongs_to :user

  has_and_belongs_to_many :feeds

  attr_accessible :content, :feeds, :feeds_attributes

end

Feed

class Feed < ActiveRecord::Base
  has_and_belongs_to_many :broadcasts
  attr_accessible :name
end

On my client, I have basic ActiveResource classes for those models.

When I try to create new Broadcast with given Feeds (from client):

feed = Feed.find(3) <-succesful

broadcast = Broadcast.new
broadcast.attributes['feed'] ||= [] 
broadcast.feed << feed
broadcast.save

In BroadcastController on the server, I simply do

@broadcast = Broadcast.new(params[:broadcast])

it gives following error:

ActiveRecord::AssociationTypeMismatch (Feed(#45931224) expected, got
ActiveSupport::HashWithIndifferentAccess(#25685616)):

I tried changing

broadcast.attributes['feed'] ||= [] 

to

broadcast.attributes['feed_attributes'] ||= [] 

But it gave me “Unknown attribute error”

Answer 1

nevermind, I was missing:

accepts_nested_attributes_for :feeds

in my Broadcast method.

Anyway, should anyone encounter this question, please note that:

broadcast.attributes['feed_attributes'] ||= [] 

is correct, without ‘_attributes’ suffix the HashWithIndifferentAccess error still occurs.