hsribei / goalie

Custom error pages for Rails

Goalie

Goalie is a flexible dynamic error response renderer for Rails built on Rack and Rails Engines. It provides the same default error pages as Rails, but allows you to easily customize them with dynamic content. This means you can use your application layout, have different error pages for different subdomains, and do all sorts nice things.

Installation

gem install goalie

After you install it and add it to your Gemfile, you have to require it together with Rails' frameworks at the top of your config/application.rb file:

require 'goalie/rails'

This will remove Rails' default exception renderer middleware (ShowExceptions) and use Goalie's instead. Unless you have custom static pages in your public directory (which we plan to support later), this will be a drop-in replacement.

Customization

Controllers

The public (production) rescuing of errors is done by the PublicErrorsController found in Goalie's app/controllers directory. If you create a controller with the same name, it will automatically be used instead of Goalie's. All it needs to do is support the following actions:

• internal_server_error
• not_found
• unprocessable_entity
• conflict
• method_not_allowed
• not_implemented

If you don't actually need a separate action for each of these errors, you can redirect them to others, for example, with:

def unprocessable_entity
  render :action => 'internal_server_error'
end

Views

You can also customize only the views and use Goalie's default controller. All you need is to have inside app/views/public_errors views with the same names as the actions listed above.

Besides the standard stuff that Rails makes available to views, you will also have access to the following instance variables if you include the Goalie::ErrorDetails module:

• @request
• @exception
• @application_trace
• @framework_trace
• @full_trace

Be VERY careful when using this in production, as you could expose sensitive information inside the request and exception. Generally, you probably shouldn't use these variables at all. The only place it makes sense is to have a more detailed error screen for admins or other high-level users. By default these details are not available to the public errors views but can be made available if you override the PublicErrorsController and include the Goalie::ErrorDetails module.

Credit

Goalie copies a lot of code and ideas from:

• Rails' ShowExceptions middleware
• Rails' default error views
• Rails' exception_notification plugin

Which are mostly the work of Joshua Peek, with help from various contributors. We're highly indebted to them and thank them a lot for their work.

Contributions

Any form of feedback, patches, issues, and documentation are highly appreciated.

License

MIT license. Copyright 2010 Helder Ribeiro.

goalie's Issues

Can't access current_user (devise) in dynamic error pages

Hi,

I tried out your gem this morning and it looks like a very promising solution to (what I see) as a problem in Rails 3. After trying differing solutions all morning yours is the only solid one. I'm very close to getting it working fully but have two issues off getting it perfect.

The first is that my current_user (via devise) is throwing an error

  Error during failsafe response: ActionView::Template::Error

/Users/jack/.rvm/gems/ruby-1.9.2-p0/gems/activemodel-3.0.3/lib/active_model/attribute_methods.rb:364:in method_missing' /Users/jack/.rvm/gems/ruby-1.9.2-p0/gems/activerecord-3.0.3/lib/active_record/attribute_methods.rb:46:inmethod_missing'
/Users/jack/Code/oxnotes3/app/helpers/application_helper.rb:3:in current_seller' /Users/jack/Code/oxnotes3/site/app/views/shared/_nav_bar.html.erb:2:in_site_app_views_shared__nav_bar_html_erb___737376405_689060__547631846'
/Users/jack/.rvm/gems/ruby-1.9.2-p0/gems/actionpack-3.0.3/lib/action_view/template.rb:135:in `block in render'

The second (related) is that some of my preferences (e.g. image to be displayed on layout) is determined at db level and this isn't working either.

I'm thinking this might mean that Goalie is having issues db issues? Any ideas? Roads I should explore?

Jack

Missing template error

Using Rails 3.0.5, Ubuntu 10, goalie 0.0.4
Followed the instructions but for certain actions I get the following error in the logfile

Error during failsafe response: Missing template public_errors/internal_server_error ....

The directory public_errors exist, and the file internal_server_error.html and internal_server_error.html.erb exists.

The web browser displays the standard Rails error 500 (?)

500 Internal Server Error
If you are the administrator of this website, then please read this web application's log file and/or the web server's log file to find out what went wrong.

The controller is per your example, but using a layout

class PublicErrorsController < ApplicationController
  layout "fatal_errors"
  #403
  def forbidden
  end

  #404
  def not_found
  end

  #405
  def method_not_allowed
    render :action => 'internal_server_error'
  end

  #409
  def conflict
    render :action => 'internal_server_error'
  end

  #422
  def unprocessable_entity
  end

  #500
  def internal_server_error
  end

  #501
  def not_implemented
    render :action => 'internal_server_error'
  end
end

Doesn't use application layout by default

Using Goalie's PublicErrorsController (i.e. not overriding it) will render your public_errors views, but without the application layout.

If you override the controller with your own, the application layout is used.

Is this intentional?