NoMethodError for Best In Place gem - ruby-on-rails

Question

I'm trying to implement the Best In Place gem and have followed along with the Railscast, but am having issues. I'm learning Rails and am building a sample blog app with two models, Article and Comment. I'm trying to use Best In Place to edit comments.
_list_comments.html.erb
<% #comments.each do |comment| %>
<hr />
<%= link_to article_comment_path(#article, comment), method: :delete, data: {confirm: 'Are you sure?'}, remote: true do %>
<span class="glyphicon glyphicon-remove"></span>
<% end %>
<%= content_tag :span, '', id: "#{comment.id}", class: "glyphicon glyphicon-edit edit_comment" %>
<!--<%= content_tag :p, content_tag(:small, "#{comment.author}"), id: "comment_author_#{comment.id}" %>-->
<%= best_in_place comment, :author %>
<%= content_tag :p, id: "comment_body_#{comment.id}" do %>
<%= comment.body %>
<% end %>
<% end %>
It is giving me this error: ActionView::Template::Error (undefined method comment_path for #<#<Class:0x007fdc38fb8288>:0x007fdc38fc36b0>):, which is referring to <%= best_in_place comment, :author %>. I'm pretty sure I installed everything correctly, so I don't know what the problem is.
When I change <%= best_in_place comment, :author %> to <%= best_in_place "#{comment}", :author %>, it gives me this error: undefined method 'author' for "#<Comment:0x007fdc3c841820>":String.
comments_controller.html.erb
class CommentsController < ApplicationController
def create
#comment = Comment.new(comment_params)
#comment.article_id = params[:article_id]
if #comment.save
respond_to do |f|
f.html { redirect_to article_path(params[:article_id]), notice: 'Comment created!' }
f.js {
#article = Article.find(params[:article_id])
#comment = #comment
#comments = Comment.where(article_id: params[:article_id])
}
end
else
redirect_to article_path(params[:article_id]), warning: 'Unable to create comment.'
end
end
def destroy
#comment = Comment.find(params[:id]).destroy
respond_to do |f|
f.html { redirect_to article_path(params[:article_id]) }
f.js {
#article = Article.find(params[:article_id])
#comments = Comment.where(article_id: params[:article_id])
}
end
end
def update
#comment = Comment.find(params[:id])
if #comment.update(comment_params)
respond_to do |f|
f.html { redirect_to article_path(#comment.article_id) }
f.json { render head :ok}
end
else
respond_to do |f|
f.html { redirect_to article_path(#comment.article_id) }
f.json { render json: #comment.errors.full_messages, status: :unprocessable_entity }
end
end
end
private
def comment_params
params.require(:comment).permit(:author, :body)
end
end

Answer 1

I was able to clone your project and figure out why you are getting this error:
undefined method comment_path for #<#<Class:0x007fdc38fb8288>:0x007fdc38fc36b0>
Here is what's happening. In this code <%= best_in_place comment, :author %>, you are passing comment object. best_in_place is trying to map it to a route helper named comment_path by appending path to comment (hint: undefined method comment_path).
Your routes are set up this way:
resources :articles do
resources :comments
end
if you do rake routes, you'll notice that you don't have a helper path named comment_path which corresponds to your comments#show. It is looking for comment_path and it can't find it. hence, the error message.
However, since you are using nesting resources the helper path that corresponds to the comments#show is called article_comment_path. here is the complete mapping:
article_comment_path GET /articles/:article_id/comments/:id(.:format) comments#show
To get best_in_place map to the correct helper path, there are two ways you can solve this:
1) create a route that maps to comment_path by simply adding this route to your routes.rb file:
resources :comments, only: [:show]
The full mapping for the above route is:
comment_path GET /comments/:id(.:format) comments#show
you now have comment_path. No more error message.
2) Tweak your code to map to article_comment_path
replace:
<%= best_in_place comment, :author %>
with:
<%= best_in_place [#article, comment], :author %>
The array, [#article, comment], will build the helper path article_comment_path by appending comment to #article