Guard

Guard is a command line tool that easily handle events on files modifications.

If you have any questions please join us on our Google group or on #guard (irc.freenode.net).

Features

• FSEvent support on Mac OS X 10.5+ (without RubyCocoa!, rb-fsevent gem, >= 0.3.5 required).
• Inotify support on Linux (rb-inotify gem, >= 0.5.1 required).
• Directory Change Notification support on Windows (rb-fchange, >= 0.0.2 required).
• Polling on the other operating systems (help us to support more OS).
• Automatic & Super fast (when polling is not used) files modifications detection (even new files are detected).
• Growl notifications (growl_notify gem or growlnotify & growl gem required).
• Libnotify notifications (libnotify gem required).
• Tested against Ruby 1.8.7, 1.9.2 and REE.

Screencast

Ryan Bates made a screencast on Guard, you can view it here: http://railscasts.com/episodes/264-guard

Install

Install the gem:

$ gem install guard

Add it to your Gemfile (inside the development group):

gem 'guard'

Generate an empty Guardfile with:

$ guard init

You may optionally place a .Guardfile in your home directory to use it across multiple projects.

Add the guards you need to your Guardfile (see the existing guards below).

On Mac OS X

Install the rb-fsevent gem for FSEvent support:

$ gem install rb-fsevent

Install either the growl_notify or the growl gem if you want notification support:

$ gem install growl_notify
$ # or
$ gem install growl

And add them to your Gemfile:

gem 'rb-fsevent'
gem 'growl'

The difference between growl and growl_notify is that growl_notify uses AppleScript to display a message, whereas growl uses the growlnotify command. In general the AppleScript approach is preferred, but this is currently known to not work in conjunction with Spork.

On Linux

Install the rb-inotify gem for inotify support:

$ gem install rb-inotify

Install the Libnotify gem if you want notification support:

$ gem install libnotify

And add them to your Gemfile:

gem 'rb-inotify'
gem 'libnotify'

On Windows

Install the rb-fchange gem for Directory Change Notification support:

$ gem install rb-fchange

Install the win32console gem if you want colors in your terminal:

$ gem install win32console

Install the Notifu gem if you want notification support:

$ gem install rb-notifu

And add them to your Gemfile:

gem 'rb-fchange'
gem 'rb-notifu'
gem 'win32console'

Usage

Just launch Guard inside your Ruby / Rails project with:

$ guard [start]

or if you use Bundler, to run the Guard executable specific to your bundle:

$ bundle exec guard [start]

Guard will look for a Guardfile in your current directory. If it does not find one, it will look in your $HOME directory for a .Guardfile.

Command line options

-c/--clear option

Shell can be cleared after each change:

$ guard --clear
$ guard -c # shortcut

-n/--notify option

Notifications (growl/libnotify) can be disabled:

$ guard --notify false
$ guard -n f # shortcut

Notifications can also be disabled globally by setting a GUARD_NOTIFY environment variable to false

-g/--group option

Only certain guards groups can be run (see the Guardfile DSL below for creating groups):

$ guard --group group_name another_group_name
$ guard -g group_name another_group_name # shortcut

-d/--debug option

Guard can be run in debug mode:

$ guard --debug
$ guard -d # shortcut

-w/--watchdir option

Guard can watch in any directory (instead of the current directory):

$ guard --watchdir ~/your/fancy/project
$ guard -w ~/your/fancy/project # shortcut

-G/--guardfile option

Guard can use a Guardfile not located in the current directory:

$ guard --guardfile ~/.your_global_guardfile
$ guard -G ~/.your_global_guardfile # shortcut

An exhaustive list of options is available with:

$ guard help [TASK]

Signal handlers

Signal handlers are used to interact with Guard:

• Ctrl-C - Calls each guard's #stop method, in the same order they are declared in the Guardfile, and then quits Guard itself.
• Ctrl-\ - Calls each guard's #run_all method, in the same order they are declared in the Guardfile.
• Ctrl-Z - Calls each guard's #reload method, in the same order they are declared in the Guardfile.

You can read more about configure the signal keyboard shortcuts in the wiki.

Available Guards

A list of the available guards is present in the wiki.

Add a guard to your Guardfile

Add it to your Gemfile (inside the development group):

gem '<guard-name>'

You can list all guards installed on your system with:

$ guard list

Insert default guard's definition to your Guardfile by running this command:

$ guard init <guard-name>

You are good to go, or you can modify your guards' definition to suit your needs.

Guardfile DSL

The Guardfile DSL consists of just three simple methods: #guard, #watch & #group.

Required:

• The #guard method allows you to add a guard with an optional hash of options.

Optional:

• The #watch method allows you to define which files are supervised by this guard. An optional block can be added to overwrite the paths sent to the guard's #run_on_change method or to launch any arbitrary command.
• The #group method allows you to group several guards together. Groups to be run can be specified with the Guard DSL option --group (or -g). This comes in handy especially when you have a huge Guardfile and want to focus your development on a certain part. Guards that don't belong to a group are considered global and are always run.

Example:

group 'backend' do
  guard 'bundler' do
    watch('Gemfile')
  end

  guard 'rspec', :cli => '--color --format doc' do
    # Regexp watch patterns are matched with Regexp#match
    watch(%r{^spec/.+_spec\.rb$})
    watch(%r{^lib/(.+)\.rb$})         { |m| "spec/lib/#{m[1]}_spec.rb" }
    watch(%r{^spec/models/.+\.rb$})   { ["spec/models", "spec/acceptance"] }
    watch(%r{^spec/.+\.rb$})          { `say hello` }

    # String watch patterns are matched with simple '=='
    watch('spec/spec_helper.rb') { "spec" }
  end
end

group 'frontend' do
  guard 'coffeescript', :output => 'public/javascripts/compiled' do
    watch(%r{^app/coffeescripts/.+\.coffee$})
  end

  guard 'livereload' do
    watch(%r{^app/.+\.(erb|haml)$})
  end
end

Using a Guardfile without the guard binary

The Guardfile DSL can also be used in a programmatic fashion by calling directly Guard::Dsl.evaluate_guardfile. Available options are as follow:

• :guardfile - The path to a valid Guardfile.
• :guardfile_contents - A string representing the content of a valid Guardfile

Remember, without any options given, Guard will look for a Guardfile in your current directory and if it does not find one, it will look for it in your $HOME directory.

For instance, you could use it as follow:

gem 'guard'
require 'guard'

Guard.setup

Guard::Dsl.evaluate_guardfile(:guardfile => '/your/custom/path/to/a/valid/Guardfile')
# or
Guard::Dsl.evaluate_guardfile(:guardfile_contents => "
  guard 'rspec' do
    watch(%r{^spec/.+_spec\.rb$})
  end
")

Listing defined guards/groups for the current project

You can list the defined groups and guards for the current Guardfile from the command line using guard show or guard -T:

# guard -T

(global):
  shell
Group backend:
  bundler
  rspec: cli => "--color --format doc"
Group frontend:
  coffeescript: output => "public/javascripts/compiled"
  livereload

Create a new guard

Creating a new guard is very easy, just create a new gem (bundle gem if you use Bundler) with this basic structure:

.travis.yml  # bonus point!
CHANGELOG.md # bonus point!
Gemfile
guard-name.gemspec
Guardfile
lib/
  guard/
    guard-name/
      templates/
        Guardfile # needed for `guard init <guard-name>`
      version.rb
    guard-name.rb
test/ # or spec/
README.md

Guard::GuardName (in lib/guard/guard-name.rb) must inherit from Guard::Guard and should overwrite at least one of the five basic Guard::Guard instance methods.

Here is an example scaffold for lib/guard/guard-name.rb:

require 'guard'
require 'guard/guard'

module Guard
  class GuardName < Guard

    def initialize(watchers=[], options={})
      super
      # init stuff here, thx!
    end

    # =================
    # = Guard methods =
    # =================

    # If one of those methods raise an exception, the Guard::GuardName instance
    # will be removed from the active guards.

    # Called once when Guard starts
    # Please override initialize method to init stuff
    def start
      true
    end

    # Called on Ctrl-C signal (when Guard quits)
    def stop
      true
    end

    # Called on Ctrl-Z signal
    # This method should be mainly used for "reload" (really!) actions like reloading passenger/spork/bundler/...
    def reload
      true
    end

    # Called on Ctrl-\ signal
    # This method should be principally used for long action like running all specs/tests/...
    def run_all
      true
    end

    # Called on file(s) modifications
    def run_on_change(paths)
      true
    end

  end
end

Please take a look at the existing guards' source code for more concrete example and inspiration.

Alternatively, a new guard can be added inline to a Guardfile with this basic structure:

require 'guard/guard'

module ::Guard
  class InlineGuard < ::Guard::Guard
    def run_all
      true
    end

    def run_on_change(paths)
      true
    end
  end
end

Here is a very cool example by @avdi : http://avdi.org/devblog/2011/06/15/a-guardfile-for-redis

Development

• Source hosted at GitHub.
• Report issues and feature requests to GitHub Issues.

Pull requests are very welcome! Make sure your patches are well tested. Please create a topic branch for every separate change you make. Please do not change the version in your pull-request.

For questions please join us on our Google group or on #guard (irc.freenode.net).

Author

Thibaud Guillaume-Gentil

Contributors

https://github.com/guard/guard/contributors