Not able to get form to submit when using nested_form with paperclip

[vmcilwain]

Hello,

I am trying to get the nested_form gem to work in rails 4.1 for adding attachments using paperclip. Everything renders as expected but when I submit the form nothing happens. No errors, no log output or anything.

I am not sure the best way to debug this problem since I basically don't have anything to go on. Has anyone else has run into this problem or can you give advice for the best way I can attack this?

What I currently have is as follows:

discussions_controller.rb:

def new
  @discussion = Discussion.new
  @discussion_group = DiscussionGroup.find(params[:discussion_group_id])
  @categories = DiscussionCategory.all.collect{|category| [category.name, category.id]}
   2.times{@discussion.discussion_attachments.build}
end

def discussion_params
  params.require(:discussion).permit(:discussion_group_id, :discussion_category_id, :subject, :body, discussion_attachments_attributes: [:id, :name, :_destroy])
end

discussion.rb

has_many :discussion_attachments, :dependent => :delete_all
accepts_nested_attributes_for :discussion_attachments, allow_destroy: true

discussion_attachment.rb

belongs_to :discussion
  has_attached_file :document
  validates_attachment :document, content_type: {content_type: ALLOWABLE_APPLICATIONS + ALLOWABLE_IMAGES}
 validates :discussion_id, :document_file_name, presence: :true

new.html.erb

<%= form_for @discussion, url: admin_discussions_path, method: :post do |f| %>
    <%= nested_form_for @discussion do |f| %>
        Upload Document
        <%= f.fields_for :discussion_attachments do |builder| %>
            <div class='field'>
                <%= builder.file_field :document %>
                <%= builder.link_to_remove "Remove this document" %>
            </div>
        <% end %>
        <%= f.link_to_add "Add a document", :discussion_attachments %>
    <% end %>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

UPDATE:
The form works as it is supposed to when I uncomment the nested_form_for block. But the moment I uncomment that block but leave the fields_for block on the inside of that commented out this issue shows. This same issue happens in rails 4.0.4.

[DavidBennettPIO]

Just a passer-by... but it looks like you forgot to add :document to your discussion_attachments_attributes array?

[Startouf]

Err, why do you have both form_for and nested_form_for ? Use one of them, but not both.

nested_form_for is gonna use the helpers provided by this gem (So you can use fields_for, link_to_add, etc..)

form_for is gonna use Rails default helpers.

<%= nested_form_for @discussion, url: admin_discussions_path, method: :post do |f| do |f| %>