Question

I have a rails app that uses partials and in development everything works great but in production I am getting the error

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I checked my production.log file and this is the error I am receiving

ActionView::Template::Error (undefined method `model_name’ for NilClass:Class):

Here is the lines that are causing the problems

<%= div_for blog do %>

and here is whats causing that file

<%= render :partial => 'blogs/blog', :locals => {:blog => @profile.blogs.last}%>

here’s the entire error

ActionView::Template::Error (undefined method `model_name' for NilClass:Class):
1: <%= div_for blog do %>
2: <p>
3:   <b>Title:</b>
4:   <%= blog.title %>
app/views/blogs/_blog.html.erb:1:in 
app/views/profiles/show.html.erb:22:in

any ideas on how I can resolve this error?

Answer 1

You are effectively calling nil.last which will throw this kind of error.

Use a conditional to render the partial only if @profile contains blogs:

<%= render(:partial => 'blogs/blog', :locals => {:blog => @profile.blogs.last}) if @profile.blogs.present? %>

Or, what I would do, use a partial. In your view:

<%= blogs_or_message %>

In a partial:

def blogs_or_message
  if @profile.blogs.present?
    render(:partial => 'blogs/blog', :locals => {:blog => @profile.blogs.last})
  else
    "No blogs found" # <= simple error message instead of nothing
  end
end