Rambulance

Rambulance provides a simple and safe way to dynamically render error pages for Rails apps.

Features

Simple and Safe

Rambulance's exceptions app is simple, skinny and well-tested. It inherits ActionController::Base, so it works fine even if your ApplicationController has an issue.

Flexible

You have full control of what error page to display for a specific exception. It can also render json responses. It even provides a way to create a custom exceptions app.

Easy installation and development

You don't have to configure things that every single person has to do and Rambulance does everything for you.

Installation and Usage

Add this line to your application's Gemfile:

gem 'rambulance'

And then execute:

$ rails g rambulance:install

or specify the template engine by:

$ rails g rambulance:install -e slim

Rambulance now support erb, haml, slim template engines, if you don't specify the -e option, erb will be used as default.

Now you can start editing templates like app/views/errors/not_found.html.erb. Edit, run rails server and open localhost:3000/rambulance/not_found!

Setting Pairs of Exceptions and HTTP Statuses

Open config/initializers/rambulance.rb and to configure the list of pairs of exception/corresponding http status. For example, if you want to display:

422(unprocessable entity) for ActiveRecord::RecordNotUnique
403(forbidden) for CanCan::AccessDenied
404(not found) for YourCustomException

Then do the following:

# config/initializers/rambulance.rb
config.rescue_responses = {
  "ActiveRecord::RecordNotUnique" => :unprocessable_entity,
  "CanCan::AccessDenied"          => :forbidden,
  "YourCustomException"           => :not_found
}

Local Development

There are 2 ways of editing the templates.

Open `localhost:3000/rambulance/***` in Your Browser

Just go to one of the error pages via Rambulance:

This is useful when you want to edit templates without changing Rails configuration.

Set `consider_all_requests_local` to false

Change config.consider_all_requests_local to false in config/environments/development.rb.

config.consider_all_requests_local = false

This simulates how your production app displays error pages so you can actually raise an exception in your app and see how it works. Don't forget to change consider_all_requests_local back to true after you tried this strategy.

Custom Exceptions App

If you want to do some more things in a exceptions app, you can also write your own custom exceptions app:

$ rails g rambulance:exceptions_app

It'll generate your own custom exceptions app. You can use whatever techniques you use in controllers like before_filter and flash[:notice] = "message..." since it's a grandchild of ActionController::Base!

Keep in mind that you shouldn't do too many things because something already went wrong with your application!

Supported Versions

Ruby 1.9.3, 2.0.0, 2.1, 2.2, JRuby 1.7.19, JRuby head, Rubinius 2.4.1 and 2.5.3
Rails 3.2, 4.0, 4.1, 4.2 and edge

Rambulance doesn't work with Rails 3.1 and below since they don't provide any way to use a custom exceptions app.

Contributing

Fork it ( https://github.com/yuki24/rambulance/fork )
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create a new Pull Request