Question

I am trying to create form that contains another model in rails. I have accomplished this with using accepts_nested_attibutes and it is working great. The problem is I have an additional field in that table that records the User Name for each comment and I am not sure on how to insert that information when a new comment is being created. The username is being supplied by the Application Controller using the “current_user” method.

Regards,
Kyle

Comment Model

    class Comment < ActiveRecord::Base
     belongs_to :post
     before_save :set_username

    private
     def set_username
      self.created_by = current_user
     end
    end

Application Controller (This is just a Sandbox app so I just put a string in the method)

class ApplicationController < ActionController::Base
  protect_from_forgery
  helper_method :current_user

  def current_user
    "FName LName"
  end

end

Show View

<p id="notice"><%= notice %></p>
<p>
  <b>Title:</b>
  <%= @post.title %>
</p>
<div id="show_comments"><%= render 'comments' %></div>
<div id="add_comments">
    Add Comment
    <%= form_for @post, :url => {:action => 'update', :id => @post.id}, :html => { :'data-type' => 'html', :id => 'create_comment_form' } do |f| %>
        <%= f.fields_for :comments, @new_comment do |comment_fields| %>
            <%= comment_fields.text_area :content %>
        <%end%>
      <div class="validation-error"></div>
      <%= f.submit %>
    <% end %>
</div>

Post Controller

  def update
    @post = Post.find(params[:id])
    respond_to do |format|
      if @post.update_attributes(params[:post])
        @comments = @post.comments.all
        format.html { redirect_to({:action => :show, :id => @post.id}, :notice => 'Post was successfully created.') }
        format.xml  { render :xml => @post, :status => :created, :location => @post }
      else
        format.html { render :action => "new" }
        format.xml  { render :xml => @post.errors, :status => :unprocessable_entity }
      end
    end
  end

Answer 1

I was originally thinking you could just set it as a default or a before_save in the model. But models don’t have access to current_user. So it’s probably best to just set the current user in the controller. It’s not as DRY as putting it in the model but it’s less hackey and potentially problematic this way.

def update
  @post = Post.find(params[:id])
  @post.attributes = params[:post]
  @post.comments.each do |comment|
    comment.created_by = current_user if comment.new_record?
  end
  respond_to do |format|
    if @post.save
      @comments = @post.comments.all
      format.html { redirect_to({:action => :show, :id => @post.id}, :notice => 'Post was successfully created.') }
      format.xml  { render :xml => @post, :status => :created, :location => @post }
    else
      format.html { render :action => "new" }
      format.xml  { render :xml => @post.errors, :status => :unprocessable_entity }
    end
  end
end