Skip to content


Subversion checkout URL

You can clone with
Download ZIP
Every Rails page has footnotes that gives information about your application and links back to your editor
Ruby Other

Fetching latest commit…

Cannot retrieve the latest commit at this time

Failed to load latest commit information.


Rails Footnotes
License: MIT
Version: 3.7.0

You can also read this README in pretty html at the GitHub project Wiki page


If you are developing in Rails you should know the plugin! It displays
footnotes in your application for easy debugging, such as sessions,
request parameters, cookies, filter chain, routes, queries, etc.

Even more, it contains links to open files directly in your editor including
your backtrace lines.


Since this branch aims Rails 3 support, if you want to use it with Rails 2.3 you should check this branch:

Install Rails Footnotes is very easy.

Rails 2.x

In RAILS_ROOT/config/environments/development.rb (yes, you want it only in development):

  gem "rails-footnotes", '< 3.7.0', :group => :development

Rails 3.x

   gem 'rails-footnotes', '>= 3.7', :group => :development


For version greater then 3.7.0

If you want to add alternate logic to enable or disable footnotes,
add something like this to config/initializers/footnotes.rb:

  if defined?(Footnotes) & Rails.env.development?! # first of all

    # ... other init code


    Footnotes.setup do |config|
      config.before {|controller, filter| filter.notes = =~ /Message/ && \
        controller.action_name == 'index' ? [:assigns] : []}
      config.before {|controller, filter| filter.notes |= [:params] if =~ /Profile/ && \
        controller.action_name == 'edit' }

If you are not using Textmate as text editor, in your environment.rb or
in an initializer do:

  Footnotes::Filter.prefix = 'mvim://open?url=file://%s&amp;line=%d&amp;column=%d'

for MacVim

Where you are going to choose a prefix compatible with your text editor. The %s is
replaced by the name of the file, the first %d is replaced by the line number and
the second %d is replaced by the column.

By default, footnotes are appended at the end of the page with default stylesheet. If you want
to change their position, you can define a div with id "footnotes_holder" or define your own stylesheet
by turning footnotes stylesheet off:

  Footnotes::Filter.no_style = true

Another option is to allow multiple notes to be opened at the same time:

  Footnotes::Filter.multiple_notes = true

If you have New Relic RPM installed, you may want to turn off query explains
(explains can slows things down)

  Footnotes::Notes::QueriesNote.sql_explain = false

Finally, you can control which notes you want to show. The default are:

  Footnotes::Filter.notes = [:session, :cookies, :params, :filters, :routes, :env, :queries, :log, :general]

Creating your own notes

Create your notes to integrate with Footnotes is easy.

1. Create a Footnotes::Notes::YourExampleNote class

2. Implement the necessary methods (check abstract_note.rb file in lib/notes)

3. Append your example note in Footnotes::Filter.notes array (usually at the end of your environment file or in an initializer):

For example, to create a note that shows info about the user logged in your application you just have to do:

  module Footnotes
    module Notes
      class CurrentUserNote < AbstractNote
        # This method always receives a controller
        def initialize(controller)
          @current_user = controller.instance_variable_get("@current_user")

        # Returns the title that represents this note.
        def title
          "Current user: #{}"

        # This Note is only valid if we actually found an user
        # If it's not valid, it won't be displayed
        def valid?

        # The fieldset content
        def content

Then put in your environment:

  Footnotes::Filter.notes += [:current_user]


* Leon Li       -
* Keenan Brock  -
* Ivan Storck   -
* Kris Chamber  -

Bugs and Feedback

If you discover any bugs, please send an e-mail to
If you just want to give some positive feedback or drop a line, that's fine too!

Version 3.x

This plugin was maintained until version 3.6 by José Valim

Copyright (c) 2009 José Valim (

Version 2.0

This plugin was created and maintained until version 2.0 by Duane Johnson:

Copyright (c) 2006 InquiryLabs, Inc.
Something went wrong with that request. Please try again.