Question

I have a author model

class Author
  include Mongoid::Document
  field :name

end

In My article form i want to bring all authors

 <div class="field">
    <%= f.label :author_tokens, "Authors" %><br />
    <%= f.text_field :author_tokens, "data-pre"=> @article.authors.map(&:attributes).to_json %>
  </div>

It is working. all authors name are seen. now i want to submit all author name i click inside Authors. what should be my article model for this? I am confuse. Here when i publish

{"utf8"=>"✓",
 "authenticity_token"=>"bE0PpLx+qBUJqIavfvpDOjzrhIHFku+IrgjnU0OLOC8=",
 "article"=>{"name"=>"ram",
 "published_on(1i)"=>"2012",
 "published_on(2i)"=>"8",
 "published_on(3i)"=>"20",
 "author_tokens"=>"",
 "content"=>"fdsfds"},
 "commit"=>"Create Article"}

author_tokens field is empty.
I have my article model

class Article

  include Mongoid::Document
  include Mongoid::Timestamps
  include Mongoid::MultiParameterAttributes
  field :name
  field :content
  field :author_tokens
  field :token_inputs
 field :published_on, :type => Date 
 validates_presence_of :name,:content

has_many :authors
 attr_reader :author_tokens

 def author_tokens=(ids)
 self.author_ids =ids.split
 end

end

What should be my article model so that i can save all input author tokens name in my article collection?

Answer 1

On the Article model, try removing:

field :author_tokens

and adding:

attr_accessible :author_tokens

Also, not sure where the token_inputs field is getting used. Maybe unnecessary?

EDIT:

I overlooked this earlier, but you need has_and_belongs_to_many on both sides of the relation for this to even work the way you want, so:

Class Author
  has_and_belongs_to_many :articles
  ...
end

and:

Class Article
  has_and_belongs_to_many :authors
  # has_many :authors <- Remove this
  ...
end

To clarify my original explanation:

1) The setter method you wrote for author_tokens and the attr_reader : author_tokens are both fine, but if you’re using mass assignment in the controller (likely), you need to make the author_tokens attribute mass assignable with attr_accessible :author_tokens. Mongoid might do this automatically if you haven’t explicitly set anything else as attr_accessible yet, depending on what version you’re using.

2) You shouldn’t need the field :author_tokens line since it’s a virtual attribute accessed via the setter you wrote, and the attr_reader call. You don’t actually want to store the value the user passes into author_tokens in the DB, you want the setter to put those values into the author_ids field for you.

3) The has_and_belongs_to_many :authors call will have created the author_ids field in the document for you.

4) Assuming you’re using the pattern shown here, the front-end implementation should be no different when using Mongoid instead of ActiveRecord.