Using AJAX to display error message Ruby on Rails

Question

I have built a blog using Ruby on Rails. New to both. I am implementing AJAX pretty effectively until I get to the error handling portion.

I allow for comments on posts and do this by rendering a comment partial and remote form in the /views/posts/show.html.erb page. Upon successful save of a comment the show page is updated using views/comments/create.js.rjs and displays a flash notice.

I am simply trying to flash a notice when it doesn't save. Searched around and worked this a bit on my own. Can't get it to fly. Here is my code:

/views/posts/show.html.erb

<div id="comments">

    <%= render :partial => @post.comments %>
    <div id="notice"><%= flash[:notice] %></div> 
</div>

<% remote_form_for [@post, Comment.new] do |f| %>

    <p>
        <%= f.label :body, "New Comment" %><br/>
        <%= f.text_area (:body, :class => "textarea") %>
    </p>
    <p>
        <%= f.label :name, "Name" %><br/>
        <%= f.text_field (:name, :class => "textfield") %>
    </p>
    <p>
        <%= f.label :email, "Email" %><br/>
        <%= f.text_field (:email, :class => "textfield") %>
    </p>
    <p><%= f.submit "Add Comment" %></p>
<% end %>

/views/comments/_comment.html.erb

<% div_for comment do %>
<div id="comment-wrapper">

        <%  if admin? %>
        <div id="comment-destroy"><%=link_to_remote "X", :url => [@post, comment], :method => :delete %></div>
        <% end %>
        <%= h(comment.body) %><br/><br/>
        <div class="small">Posted <%= time_ago_in_words(comment.created_at) %> ago by <%= h(comment.name) %> 
        <%  if admin? %>
         | <%= h(comment.email) %>

        <% end %></div>

    </div>
<% end %>

/views/comments/create.js.rjs

page.insert_html :bottom, :comments, :partial => @comment
page[@comment].visual_effect :highlight 
page[:new_comment].reset
page.replace_html :notice, flash[:notice]
flash.discard

CommentsController#create

 def create
   @post = Post.find(params[:post_id])
   @comment = @post.comments.create!(params[:comment])

   respond_to do |format|
     if @comment.save
       flash[:notice] = "Thanks for adding this comment" 
       format.html { redirect_to @post }
       format.js
     else
       flash[:notice] = "Make sure you include your name and a valid email address" 
       format.html { redirect_to @post }
       format.js

   end
 end
end 

Answer 1

The create! is a problem because create! raises an exception when the model is invalid, meaning the respond_to code below it will not execute.

Like Corey says, replace create! with build. Your strategy of displaying the flash notice via rjs may well work then.