Paperclip in Rails 4 - Strong Parameters Forbidden Attributes Error

paperclip, paperclip-validation, ruby-on-rails-4, strong-parameters

Solution

I understand what happened here now - and will leave this up in the hope it helps someone else. I was porting code from a rails 3 project and missed the line that created the image:

@image = current_user.images.new(params[:image])

In rails 4 this is incorrect (I beleive). I updated to

@image = current_user.images.new(image_params)

and that solved my problem.

Problem

Having a problem with a Paperclip upload in Rails 4 - failing on ForbiddenAttributesError (strong parameters validation). Have the latest paperclip gem and latest rails 4 gems. I have a model "Image" with an attached file "upload" in the model: ``` has_attached_file :upload, :styles => { :review => ["1000x1200>", :png], :thumb => ["100x100>", :png]}, :default_url => "/images/:style/missing.png" ``` The image model was created with a scaffold, and I added paperclip migrations. The form partial was updated to use ``` f.file_field :upload ``` the form generates what appears to be a typical set of paperclip params, with the image param containing the upload. I am also passing a transaction_id in the image model, so it should be permitted. But that's it - the image and the transaction ID. I expected to be able to write the following in my controller to whitelist my post - but it failed: ``` def image_params params.require(:image).permit(:transaction_id, :upload) end ``` So I got more explicit - but that failed too: ``` def image_params params.require(:image).permit(:transaction_id, :upload => [:tempfile, :original_filename, :content_type, :headers]) end ``` I'm a bit frustrated that Rails 4 is not showing me what ForbiddenAttributesError is failing on in a development environment - it is supposed to be showing the error but it does not - would be a nice patch to ease development. Or perhaps everyone else is getting something that I am missing! Thanks much for the help.

Original source