Has_many relationships

In my model I have two classes, a donation class and a good class. A
donation can have mulitple goods, so I set up a has_many relationship
between the two objects.

class Donation < ActiveRecord::Base
has_many :goods

class Good < ActiveRecord::Base
belongs_to :donation

In my view (donation/new.html.erb), I add goods to a donation the
following way;

This will create the following @params after submitting the form.

“description”=>“Children books”},
“description”=>“Leather Boots”},
“description”=>“wool blankets”},}}}

The donation controller:

class DonationsController < ApplicationController
def create
@donation = Donation.new(params[:donation])

So, I was hoping that ruby on rails automatically generates the goods
and adds them to the donation object, but when create is called, i get
the following error on the first line;

ActiveRecord::AssociationTypeMismatch in DonationsController#create

Good expected, got Array

Any help is appreciated.

Thanks. Is there some way to manipulate the @params info so that ruby
automates this process?

On Jan 29, 1:21 pm, Chris O. [email protected]

There is a lot of magic in rails, but not that much.

Based on the @params info that you showed you will have to extract the
donation info, create the object and manually make the relations to the

def create
@donation = Donation.new(params[:donation])
params[:donation][:goods].each do |g|

if @donation.save


Or something like that.

Franz Obenhauser wrote:

Thanks. Is there some way to manipulate the @params info so that ruby
automates this process?

On Jan 29, 1:21 pm, Chris O. [email protected]

I think I could explain this if I had to, but let me send you someplace
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