Using paperclip gem to add an attachment - ruby-on-rails

Question

I've attempted to use the paperclip gem to add attachments to my contact model. It looks as though I can add an attachment - I can select the file without a problem. However when I then create the contact, the attachment is not saved. I know this because I can see in the rails console that the document_id is 'nil'.
In the _form.html.erb for creating a new contact, I have:
<%= simple_form_for(#contact, html: {class: "form-inline well", multipart: true}, role: "form") do |f| %>
<% if #contact.errors.any? %>
<div id="error_explanation">
<h2><%= pluralize(#contact.errors.count, "error") %> prohibited this contact from being saved:</h2>
<ul>
<% #contact.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="form-group">
<%= f.input :name %>
<%= f.input :category %>
<%= f.input :area %>
<%= f.input :phone %>
<%= f.input :website %>
<%= f.input :email %>
<%= f.fields_for :document do |document_fields| %>
<%= document_fields.input :attachment, as: :file %>
<% end %>
<%= f.button :submit, class: "btn-success" %>
</div>
<% end %>
my db migration for this was:
class CreateDocuments < ActiveRecord::Migration
def change
create_table :documents do |t|
t.integer :user_id
t.timestamps
end
add_index :documents, :user_id
add_attachment :documents, :add_attachment
add_column :contacts, :document_id, :integer
end
end
My model for document.rb is:
class Document < ActiveRecord::Base
has_attached_file :attachment, :styles => { :medium => "300x300>", :thumb => "100x100>" }, :default_url => "/images/:style/missing.png"
validates_attachment_content_type :attachment, :content_type => /\Aimage\/.*\Z/
end
and for contact.rb is:
class Contact < ActiveRecord::Base
belongs_to :user
belongs_to :document
accepts_nested_attributes_for :document
validates :name, presence: true,
length: { minimum: 2}
validates :user_id, presence: true
end
and my actions in the contacts_controller.rb are:
def create
#contact = current_user.contacts.new(contact_params)
respond_to do |format|
if #contact.save
format.html { redirect_to #contact, notice: 'Contact was successfully created.' }
format.json { render action: 'show', status: :created, location: #contact }
else
format.html { render action: 'new' }
format.json { render json: #contact.errors, status: :unprocessable_entity }
end
end
end
def contact_params
params.require(:contact).permit(:name, :email, :category, :area, :organisation, :website, :phone, :user_id, document_attributes: [:id, :attachment])
end
# PATCH/PUT /contacts/1
# PATCH/PUT /contacts/1.json
def update
#contact = current_user.contacts.find(params[:id])
if params[:contact] && params[:contact].has_key?(:user_id)
params[:contact].delete(:user_id)
end
respond_to do |format|
if #contact.update((contact_params))
format.html { redirect_to #contact, notice: 'Contact was successfully updated.' }
format.json { head :no_content }
else
format.html { render action: 'edit' }
format.json { render json: #contact.errors, status: :unprocessable_entity }
end
end
end
When I try to create a new contact with an attachment, here is my heroku log:
2014-03-10T23:41:49.594786+00:00 app[web.1]: Parameters:
{"utf8"=>"✓",
"authenticity_token"=>"FGitLGkHzfw15yksCusGDvwdb//CgMyOMFh4SS4l63Y=",
"contact"=>{"name"=>"Oliver OT", "category"=>"OT", "area"=>"Rockdale",
"phone"=>"", "website"=>"", "email"=>"",
"document_attributes"=>{"attachment"=>#,
#original_filename="Screen Shot 2014-03-03 at 9.24.40 pm.png",
#content_type="image/png", #headers="Content-Disposition: form-data;
name=\"contact[document_attributes][attachment]\"; filename=\"Screen
Shot 2014-03-03 at 9.24.40 pm.png\"\r\nContent-Type:
image/png\r\n">}}, "commit"=>"Create Contact"}
2014-03-10T23:41:49.594786+00:00 app[web.1]: Parameters:
{"utf8"=>"✓",
"authenticity_token"=>"FGitLGkHzfw15yksCusGDvwdb//CgMyOMFh4SS4l63Y=",
"contact"=>{"name"=>"Oliver OT", "category"=>"OT", "area"=>"Rockdale",
"phone"=>"", "website"=>"", "email"=>"",
"document_attributes"=>{"attachment"=>#,
#original_filename="Screen Shot 2014-03-03 at 9.24.40 pm.png",
#content_type="image/png", #headers="Content-Disposition: form-data;
name=\"contact[document_attributes][attachment]\"; filename=\"Screen
Shot 2014-03-03 at 9.24.40 pm.png\"\r\nContent-Type:
image/png\r\n">}}, "commit"=>"Create Contact"}
I'm not sure how get the attachment to save correctly?

Answer 1

Move the contact_params method outside of the update action so it can be accessed by the create action and change it to the following code.
def contact_params
params.require(:contact).permit(:name, :email, :category, :area, :organisation, :website, :phone, :user_id, document_attributes: [:id, :attachment])
end
The code above allows the id and attachment params for document_attributes.

Answer 2

Your migration has a problem:
add_attachment :documents, :add_attachment
This will mean your database table will have the attachment columns as add_attachment instead, thus causing Paperclip not to work
You'll need to change the columns in your db with a migration like this:
class Migration < ActiveRecord::Migration
def change
rename_column :documents, :add_attachment_file_name, :attachment_file_name
rename_column :documents, :add_attachment_content_type, :attachment_content_type
rename_column :documents, :add_attachment_file_size, :attachment_file_size
rename_column :documents, :add_attachment_updated_at, :attachment_updated_at
end
end