Question

I have a system setup where users can post microposts (basically status updates) and upload a photo to go with the micropost.

I have:

Micropost model (has_one photo)
Photo_album model (has_many photos)
Photo model (belongs_to micropost, belongs_to photo_album)

User fills in text in text area and selects a photo. Upon submission the microposts table is updated with micropost related data such as content, created_at etc.

At the same time I want my photos table (Photo model) updated with the photo selection the user made but the correct photo album. If you look below you can see in my users_controller the instance variable @photo’s value. This insures that the photo uploaded is linked to the correct photo album which is named “microposts album”. It’s purpose is to link up to all micropost related photos.

I have a Users_controller:

  def new
     @user = User.new 
     @micropost = Micropost.new(:user_id => users_id)
     @photo = Photo.new(:photo_album_id => PhotoAlbum.where(:user_id => current_user.id, :album_title => "microposts album").first.id)
  end

From a previous question I asked it was established I needed to use accepts_nested_attributes_for, fields_for in order to be able to update more than one model with one form. This is how I’ve set things up.

Micropost model:

class Micropost < ActiveRecord::Base

  belongs_to :user
  has_one  :photo
  accepts_nested_attributes_for :photo
  attr_accessible :content, :user_id, :poster_id, :username, :image, :remote_image_url

end

Photo model:

class Photo < ActiveRecord::Base

  belongs_to :photo_album

    attr_accessible :photo_album_id, :photo_title, :image, :remote_image_url
    mount_uploader :image, ImageUploader

end

Finally here is the micropost form:

= form_for @micropost, :remote => true do |f|
    = f.fields_for @photo do |p|
        = p.file_field :image
    = f.hidden_field :user_id
    = f.text_area :content
    = f.submit "Post"

At first I got the error:

ActiveModel::MassAssignmentSecurity::Error (Can't mass-assign protected attributes: photo):

I was slightly confused because I thought the attributes were assigned automatically. At lesast thats what I read in the docs anyway. Anyway I went ahead and added :photo to the micropost model attr_accessible white list.

That first error went then I got this one:

ActiveRecord::AssociationTypeMismatch (Photo(#2169424320) expected, got ActiveSupport::HashWithIndifferentAccess(#2157396720)):

Maybe I’ve misunderstood how this feature works but I’ve read through this and also looked at the 3.2.3 api doc but not where I’m going wrong.

I would really appreciate some help with getting this to work.

Thanks in advance and I hope the long post was off putting. Just thought providing all this info would make people understand what I’m trying to do better.

Kind regards

Update:
Using :photo_attributes instead of photos gives me the following error:

Started POST "/microposts" for 127.0.0.1 at 2012-05-10 21:01:11 +0100
[02b23327ad83000f75c418d8739e7f49] [127.0.0.1] Processing by MicropostsController#create as JS
[02b23327ad83000f75c418d8739e7f49] [127.0.0.1]   Parameters: {"micropost"=>{"photo"=>{"image"=>#<ActionDispatch::Http::UploadedFile:0x00000102c293d8 @original_filename="7seriesbmw.jpeg", @content_type="image/jpeg", @headers="Content-Disposition: form-data; name=\"micropost[photo][image]\"; filename=\"7seriesbmw.jpeg\"\r\nContent-Type: image/jpeg\r\n", @tempfile=#<File:/var/folders/fh/fhADKPjGG8qSuCeoHCTNYE+++TI/-Tmp-/RackMultipart20120510-14787-1e1mrhh>>}, "user_id"=>"2", "content"=>"ioo"}, "commit"=>"Post", "utf8"=>"✓", "authenticity_token"=>"/y8Lr+e7xgabt60GWxnMGvCtIi7IjqrYDoA84vAqYcE=", "remotipart_submitted"=>"true", "X-Requested-With"=>"IFrame", "X-Http-Accept"=>"text/javascript, application/javascript, application/ecmascript, application/x-ecmascript, */*; q=0.01"}
[02b23327ad83000f75c418d8739e7f49] [127.0.0.1]   User Load (0.3ms)  SELECT `users`.* FROM `users` WHERE `users`.`id` = 2 LIMIT 1
[02b23327ad83000f75c418d8739e7f49] [127.0.0.1] Completed 500 Internal Server Error in 649ms
[02b23327ad83000f75c418d8739e7f49] [127.0.0.1] 
ActiveModel::MassAssignmentSecurity::Error (Can't mass-assign protected attributes: photo):
  app/controllers/microposts_controller.rb:9:in `create'

After changing the attr_accessor back to :photo instead of :photo_attributes:

Started POST "/microposts" for 127.0.0.1 at 2012-05-10 21:20:07 +0100
[985e0f204bf7ffac1f7c02fbec35ad9b] [127.0.0.1] Processing by MicropostsController#create as JS
[985e0f204bf7ffac1f7c02fbec35ad9b] [127.0.0.1]   Parameters: {"micropost"=>{"photo"=>{"image"=>#<ActionDispatch::Http::UploadedFile:0x00000102f8a3b0 @original_filename="7seriesbmw.png", @content_type="image/png", @headers="Content-Disposition: form-data; name=\"micropost[photo][image]\"; filename=\"7seriesbmw.png\"\r\nContent-Type: image/png\r\n", @tempfile=#<File:/var/folders/fh/fhADKPjGG8qSuCeoHCTNYE+++TI/-Tmp-/RackMultipart20120510-15197-9rt2xn>>}, "user_id"=>"2", "content"=>"pp"}, "commit"=>"Post", "utf8"=>"✓", "authenticity_token"=>"/y8Lr+e7xgabt60GWxnMGvCtIi7IjqrYDoA84vAqYcE=", "remotipart_submitted"=>"true", "X-Requested-With"=>"IFrame", "X-Http-Accept"=>"text/javascript, application/javascript, application/ecmascript, application/x-ecmascript, */*; q=0.01"}
[985e0f204bf7ffac1f7c02fbec35ad9b] [127.0.0.1]   User Load (0.4ms)  SELECT `users`.* FROM `users` WHERE `users`.`id` = 2 LIMIT 1
[985e0f204bf7ffac1f7c02fbec35ad9b] [127.0.0.1] Completed 500 Internal Server Error in 452ms
[985e0f204bf7ffac1f7c02fbec35ad9b] [127.0.0.1] 
ActiveRecord::AssociationTypeMismatch (Photo(#2180069640) expected, got ActiveSupport::HashWithIndifferentAccess(#2153916820)):
  app/controllers/microposts_controller.rb:9:in `create'

Microposts controller create action:

def create


    if params[:micropost][:user_id].to_i == current_user.id
     @micropost = current_user.microposts.build(params[:micropost])

     @comment = Comment.new(:user_id => current_user.id)
        respond_to do |format|
            if @micropost.save


            format.js   { render :post_on_springboard }

            end
        end
    else

    user = User.find_by_username(params[:micropost][:username])
    @micropost = user.microposts.build(params[:micropost])
    if @micropost.save

    UserMailer.new_wall_post_notification(user, current_user).deliver if user.email_notification == 1

    flash[:success] = "Micropost posted"
    redirect_to root_path+user.username
    else
    flash[:error] = "#{@micropost.errors.full_messages.first}"
    redirect_to root_path+user.username
    end

    end

end

Answer 1

changing

f.fields_for @photo 

to

f.fields_for :photo 

and adding

@micropost.build_photo(:photo_album_id => :photo_album_id => current_user.photo_albums.find_by_album_title("microposts album").id) 

to my microposts_controller fixed my issue