Strong Parameters: ActiveModel::ForbiddenAttributesError

Question

Lets say I have a PostsController and I have a Post model and Comment model. I'm allowing comments to be made on a Post, so on my posts/show I put the following

 # routes.rb
 resource :post do 
   member do 
      post :add_comment
    end
 end

 # post.rb
 has_many :comments

 # comment.rb
 belongs_to :post

<%= form_with(model: @post, url: add_comments_post_path) do |form| %>
   <%= form.text_area :body %>
<% end %>

# posts_controller

def add_comment
  post = Post.find(params[:id])
  post.comments.create(params[:comment])
end

private 
params.require(:post).permit(:title, :body)

I tried adding :comment on permit but it raises ActiveModel::ForbiddenAttributesError

Answer 1

I got the Strong Parameters ActiveModel::ForbiddenAttributesError fixed like so:

params.require(:post).permit(:title, :body, comment_attributes: [:body])