Form with polymorphic images - ruby-on-rails

Question

I have problems with adding pictures for comments. Comments have a link has_many to the pictures as: :imageable. How I can add a pictures upload to a comment form?
# app/models/comment.rb
class Comment < ApplicationRecord
belongs_to :article
belongs_to :user
has_many :images, as: :imageable
accepts_nested_attributes_for :images, allow_destroy: true
end
# app/models/Image.rb
class Image < ApplicationRecord
has_attached_file :img
validates_attachment :img, content_type: { content_type:
["image/jpg",
"image/jpeg", "image/png", "image/gif"] }
belongs_to :imageable, polymorphic: true, required: false
end
# app/controllers/comments_controller.rb
class CommentsController < ApplicationController
def create
#article = Article.find(params[:article_id])
#comment = #article.comments.create(comment_params)
#comment.user_id = current_user.id
#comment.save
redirect_to article_path(#article)
end
def destroy
#article = Article.find(params[:article_id])
#comment = #article.comments.find(params[:id])
#comment.destroy
redirect_to article_path(#article)
end
private
def comment_params
params.require(:comment).permit(:commenter, :body)
end
end
# app/views/comments/_form.html.erb
<%= form_with(model: [ #article, #article.comments.build ],
local:true) do |form| %>
<p>
<%= form.label :commenter %><br>
<%= form.text_field :commenter %>
</p>
<p>
<%= form.label :body %><br>
<%= form.text_area :body %>
</p>
<p>
<%= form.submit %>
</p>
<% end %>
# app/views/articles/show.html.erb
<%= render 'comments/form'%>
I managed to add images in comments through ActiveAdmin, but I dont know how to do it with form.
So, what should I add to the form for images? Should I write a method create in images_controller?

Answer 1

User PaperClip Gem.
in your view add :
<%= file_field_tag "imageables[]", type: :file, multiple: true %>
in your create method inside controller:
if params[:imageables]
params[:imageables].each { |image|
#comment.imagables.create(image: image)
}
end
Another way which is better:
Use PaperClip & Cocoon gem for nested forms.

Answer 2

If I understand your question correctly, youre asking how to nest a child form inside your Comment form. This is typically achieved with the #fields_for helper.
For a one-to-many relationship, you can simply do something like the following:
<%= form_for(...) ... do |comment_form| %>
# beginning of form for Comment ...
<p class="imageables">
<ul>
<%= form.fields_for :imageables do |comment_image_form| %>
<li>
# Add Image fields here
</li>
<% end %>
</ul>
</p>
# rest of form / submit button
<% end %>
Adapt the above to your application's current form. This is only achievable through the accepts_nested_attributes_for call you've made in Comment.
You will also need to look into whitelisting the parameters for the Image associations via the strong parameters pattern. That is, the #comment_params method of your CommentsController will need the Image attributes added, or they will be disregarded with a warning.
I also recommend you load the fields_for fields from a partial view, like this:
<%= render 'comment_image_fields', parent_form: comment_form %>
Check out the guides for nested forms for more detailed info.