File uploading Mailboxer Gem

I'm trying to send a message with an attachment in Mailboxer Gem.

My stack is : Rails 4 and Ruby 2.1.1

However, I can see that attachment using CarrierWave is already supported as the link in the code below.

https://github.com/ging/mailboxer/blob/4b2681c1790b823f7b493fb00b41e9899bb90ebe/app/models/message.rb#L13

However, I did my setup exactly like that. Normal message without an attachment is going fine.

This is my code :

Controller :

def create_message
    if params[:user].present? & params[:message].present? & params[:subject].present?
      current_user.send_message(User.find(params[:user]), params[:message], params[:subject])
      redirect_to inbox_path
    end
  end

This is my view code :

<%= form_tag do %>
    <%= select_tag 'user', options_from_collection_for_select(User.all, :id, :fullname) %><br/>
    <%= text_field_tag 'subject' %><br/>
    <%= text_area_tag 'message' %><br/>
    <%= submit_tag 'Send' %>
<% end %>

The above code is working fine and the messages are getting sent, however, when I try to add the file field to it like so and try changing the controller code, the attachment is not getting uploaded :

def create_message
    if params[:user].present? & params[:message].present? & params[:subject].present?
      current_user.send_message(User.find(params[:user]), params[:message], params[:subject], true , params[:attachment])
      redirect_to inbox_path
    end
  end

View :

<%= form_tag do %>
    <%= select_tag 'user', options_from_collection_for_select(User.all, :id, :fullname) %><br/>
    <%= text_field_tag 'subject' %><br/>
    <%= text_area_tag 'message' %><br/>
    <%= file_field_tag 'attachment' %>
    <%= submit_tag 'Send' %>
<% end %>

I think this is a problem with the strong params. In Rails 3 I could have used attr_accessible. However how do I ensure that the attachment field is not being blocked and allowed?

P.S - I have the carrierwave gem installed and I have even restarted my server multiple times.

Thanks.

I am changing my previous answer, because in fact it wasn't correct.

Basically, if your problem is like mine, it could easily be solved by adding :multipart => true to your form. At least in my case, that's why carrierwave was not picking up the attachments.

I tried to solve the problem by extending the mailboxer Message class and setting up and mounting a completely new carrierwave object with a different attribute name. Basically, this allowed me to avoid working with the attachment attribute defined in mailboxer and to customize the attachments.

But this got very messy with the extension of the mailboxer message.rb Class. So I finally abandoned that course. Still, having your own uploader instead of relying on the mailboxer attachment is very convenient, especially if you want or need to upload your files to a different directory or to the cloud.

So finally, I have created a new model for my attachments and mounted a new carrierwave uploader on it. In that way, I can customize it as I want without having to tweak mailboxer, which has very little in terms of documentation or support.

Probably this is not useful to you anymore, but might help others!