Guard

![]()
Guard is a command line tool to easily handle events on file system modifications.
This document contains a lot of information, please take your time and read these instructions carefully. If you have
any questions about the Guard usage or want to share some information with the Guard community, please go to one of
the following places:
- Google+ community
- Google group
- StackOverflow
- IRC channel
#guard(irc.freenode.net) for chatting
Information on advanced topics like creating your own Guard plugin, programatic use of Guard, hooks and callbacks and
more can be found in the Guard wiki.
Before you file an issue, make sure you have read the known issues and file an issue sections that contains some important information.
Features
- File system changes handled by our awesome Listen gem.
- Support for visual system notifications.
- Huge eco-system with more than 220 Guard plugins.
- Tested against Ruby 1.9.3, 2.0.0, JRuby (1.9 mode) & Rubinius (1.9 mode).
Screencast
Two nice screencasts are available to help you get started:
- Guard on RailsCast.
- Guard is Your Best Friend on Net Tuts+.
Installation
The simplest way to install Guard is to use Bundler.
Add Guard (and any other dependencies) to a Gemfile in your project’s root:
group :development do gem 'guard' end
then install it by running Bundler:
$ bundle
Generate an empty Guardfile with:
$ bundle exec guard init
Run Guard through Bundler with:
$ bundle exec guard
It’s important that you always run Guard through Bundler to avoid errors. If you’re getting sick of typing
bundle exec all the time, try the Rubygems Bundler.
If you are on Mac OS X and have problems with either Guard not reacting to file changes or Pry behaving strange, then
you should add proper Readline support to Ruby on Mac OS X.
Add Guard plugins
Guard is now ready to use and you should add some Guard plugins for your specific use. Start exploring the many Guard
plugins available by browsing the Guard organization on GitHub or by searching for guard-
on RubyGems.
When you have found a Guard plugin of your interest, add it to your Gemfile:
group :development do gem '' end
See the init section of the Guard usage below to see how to install the supplied plugin template that you can install and
to suit your needs.
Usage
Guard is run from the command line. Please open your terminal and go to your project work directory.
Help
You can always get help on the available tasks with the help task:
$ bundle exec guard help
Requesting more detailed help on a specific task is simple: just append the task name to the help task.
For example, to get help for the start task, simply run:
$ bundle exec guard help start
Init
You can generate a Guardfile and have all installed plugins be automatically added into
it by running the init task without any option:
$ bundle exec guard init
You can also specify the name of an installed plugin to only get that plugin template
in the generated Guardfile:
$ bundle exec guard init
You can also specify the names of multiple plugins to only get those plugin templates
in the generated Guardfile:
$ bundle exec guard init
You can also define your own templates in ~/.guard/templates/ which can be appended in the same way to your existing
Guardfile:
$ bundle exec guard init
Note: If you already have a Guardfile in the current directory, the init task can be used
to append a supplied template from an installed plugin to your existing Guardfile.
-b/--bare option
You can generate an empty Guardfile by running the init task with the bare
option:
$ bundle exec guard init --bare $ bundle exec guard init -b # shortcut
Start
Just launch Guard inside your Ruby or Rails project with:
$ bundle exec guard
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.
-c/--clear option
The shell can be cleared after each change:
$ bundle exec guard --clear $ bundle exec guard -c # shortcut
You can add the following snippet to your ~/.guardrc to have the clear option always be enabled:
Guard.options[:clear] = true
-n/--notify option
System notifications can be disabled:
$ bundle exec guard --notify false $ bundle exec guard -n f # shortcut
Notifications can also be disabled globally by setting a GUARD_NOTIFY environment variable to false.
-g/--group option
Scope Guard to certain plugin groups on start:
$ bundle exec guard --group group_name another_group_name $ bundle exec guard -g group_name another_group_name # shortcut
See the Guardfile DSL below for creating groups.
-P/--plugins option
Scope Guard to certain plugins on start:
$ bundle exec guard --plugins plugin_name another_plugin_name $ bundle exec guard -P plugin_name another_plugin_name # shortcut
-d/--debug option
Guard can display debug information which can be very usefull for plugins
developers with:
$ bundle exec guard --debug $ bundle exec guard -d # shortcut
-w/--watchdir option
Guard can watch any number of directories instead of only the current directory:
$ bundle exec guard --watchdir ~/your/fancy/project $ bundle exec guard -w ~/your/fancy/project ~/your/fancier/project2 #multiple directories $ bundle exec guard -w ~/your/fancy/project # shortcut
-G/--guardfile option
Guard can use a Guardfile not located in the current directory:
$ bundle exec guard --guardfile ~/.your_global_guardfile $ bundle exec guard -G ~/.your_global_guardfile # shortcut
-i/--no-interactions option
Turn off completely any Guard terminal interactions with:
$ bundle exec guard start -i $ bundle exec guard start --no-interactions
-B/--no-bundler-warning option
Skip Bundler warning when a Gemfile exists in the project directory but Guard is not run with Bundler.
$ bundle exec guard start -B $ bundle exec guard start --no-bundler-warning
-l/--latency option
Overwrite Listen’s default latency, useful when your hard-drive / system is slow.
$ bundle exec guard start -l 1.5 $ bundle exec guard start --latency 1.5
-p/--force-polling option
Force Listen polling listener usage.
$ bundle exec guard start -p $ bundle exec guard start --force-polling
List
You can list the available plugins with the list task:
$ bundle exec guard list +----------+--------------+ | Plugin | In Guardfile | +----------+--------------+ | Compass | ✘ | | Cucumber | ✘ | | Jammit | ✘ | | Ronn | ✔ | | Rspec | ✔ | | Spork | ✘ | | Yard | ✘ | +----------+--------------+
Show
You can show the structure of the groups and their plugins with the show task:
$ bundle exec guard show
+---------+--------+-----------------+----------------------------+
| Group | Plugin | Option | Value |
+---------+--------+-----------------+----------------------------+
| Specs | Rspec | all_after_pass | true |
| | | all_on_start | true |
| | | cli | "--fail-fast --format doc" |
| | | focus_on_failed | false |
| | | keep_failed | true |
| | | run_all | {} |
| | | spec_paths | ["spec"] |
+---------+--------+-----------------+----------------------------+
| Docs | Ronn | | |
+---------+--------+-----------------+----------------------------+
This shows the internal structure of the evaluated Guardfile or .Guardfile, with the .guard.rb file. You can
read more about these files in the shared configuration section.
Notifiers
You can show the notifiers, their availablity and options with the notifier task:
$ bundle exec guard notifiers +-------------------+-----------+------+------------------------+-------------------+ | Name | Available | Used | Option | Value | +-------------------+-----------+------+------------------------+-------------------+ | gntp | ✔ | ✘ | sticky | false | +-------------------+-----------+------+------------------------+-------------------+ | growl | ✘ | ✘ | sticky | false | | | | | priority | 0 | +-------------------+-----------+------+------------------------+-------------------+
This shows if a notifier is available on the current system, it it’s being used and the
current options (which reflects your custom options merged into the default options).
Interactions
Guard shows a Pry console whenever it has nothing to do and comes with some Guard specific Pry
commands:
↩,a,all: Run all plugins.h,help: Show help for all interactor commands.c,change: Trigger a file change.n,notification: Toggles the notifications.p,pause: Toggles the file listener.r,reload: Reload all plugins.o,scope: Scope Guard actions to plugins or groups.s,show: Show all Guard plugins.e,exit: Stop all plugins and quit Guard
The all and reload commands supports an optional scope, so you limit the Guard action to either a Guard plugin or
a Guard group like:
[1] guard(main)> all rspec [2] guard(main)> all frontend
Remember, you can always use help on the Pry command line to see all available commands and help for
more detailed information. help guard will show all Guard related commands available
Pry supports the Ruby built-in Readline, rb-readline and
Coolline. Just install the readline implementation of your choice by adding it
to your `Gemfile.
You can also disable the interactions completely by running Guard with the --no-interactions option.
Customizations
Further Guard specific customizations can be made in ~/.guardrc that will be evaluated prior the Pry session is
started (~/.pryrc is ignored). This allows you to make use of the Pry plugin architecture to provide custom commands
and extend Guard for your own needs and distribute as a gem. Please have a look at the
Pry Wiki for more information.
Signals
You can also interact with Guard by sending POSIX signals to the Guard process (all but Windows and JRuby).
If the Pry interactor is used, then Ctrl-C is delegated to Pry to exit continuation and Ctrl-D to exit Guard.
Without interactor, Ctrl-C exits Guard and Ctrl-D is ignored.
Pause watching
$ kill -USR1
Continue watching
$ kill -USR2
Guardfile DSL
The Guardfile DSL is evaluated as plain Ruby, so you can use normal Ruby code in your Guardfile.
Guard itself provides the following DSL methods that can be used for configuration:
guard
The guard method allows you to add a Guard plugin to your toolchain and configure it by passing the
options after the name of the plugin:
guard :coffeescript, input: 'coffeescripts', output: 'javascripts'
You can define the same plugin more than once:
guard :coffeescript, input: 'coffeescripts', output: 'javascripts' guard :coffeescript, input: 'specs', output: 'specs'
watch
The watch method allows you to define which files are watched by a Guard:
guard :bundler do watch('Gemfile') end
String watch patterns are matched with String#==.
You can also pass a regular expression to the watch method:
guard :jessie do watch(%r{^spec/.+(_spec|Spec)\.(js|coffee)}) end
This instructs the jessie plugin to watch for file changes in the spec folder,
but only for file names that ends with _spec or Spec and have a file type of js or coffee.
You can easily test your watcher regular expressions with Rubular.
When you add a block to the watch expression, you can modify the file name that has been
detected before sending it to the plugin for processing:
guard :rspec do watch(%r{^lib/(.+)\.rb$}) { |m| "spec/lib/#{m[1]}_spec.rb" } end
In this example the regular expression capture group (.+) is used to transform a file change
in the lib folder to its test case in the spec folder. Regular expression watch patterns
are matched with Regexp#match.
You can also launch any arbitrary command in the supplied block:
guard :shell do watch('.*') { `git status` } end
group
The group method allows you to group several plugins together. This comes in handy especially when you
have a huge Guardfile and want to focus your development on a certain part.
group :specs do guard :rspec do watch(%r{^spec/.+_spec\.rb$}) end end group :docs do guard :ronn do watch(%r{^man/.+\.ronn?$}) end end
Groups to be run can be specified with the Guard DSL option --group (or -g):
$ bundle exec guard -g specs
Guard plugins that don’t belong to a group are considered global and are always run.
Another neat use of groups is to group dependant plugins and stop processing if one fails. In order
to make this work, the group needs to have the halt_on_fail option enabled and the Guard plugin
needs to throw :task_has_failed to indicate that the action was not successful.
group :specs, halt_on_fail: true do guard :rspec do watch(/.../) end guard :cucumber do watch(/.../) end end
scope
The scope method allows you to define the default plugin or group scope for Guard, if not
specified as command line option. Thus command line group and plugin scope takes precedence over
the DSL scope configuration.
You can define either a single plugin or group:
scope plugin: :rspec scope group: :docs
or specify multiple plugins or groups.
scope plugins: [:test, :jasmine] scope groups: [:docs, :frontend]
If you define both the plugin and group scope, the plugin scope has precedence. If you use both the
plural and the singular option, the plural has precedence.
Please be sure to call the scope method after you’ve declared your Guard plugins!
notification
If you don’t specify any notification configuration in your Guardfile, Guard goes through the list of available
notifiers and enables all that are available. If you specify your preferred library, auto detection will not take
place:
notification :growl
will select the growl gem for notifications. You can also set options for a notifier:
notification :growl, sticky: true
Each notifier has a slightly different set of supported options:
notification :growl, sticky: true, host: '192.168.1.5', password: 'secret' notification :gntp, sticky: true, host: '192.168.1.5', password: 'secret' notification :growl_notify, sticky: true, priority: 0 notification :libnotify, timeout: 5, transient: true, append: false, urgency: :critical notification :notifu, time: 5, nosound: true, xp: true notification :emacs
It’s possible to use more than one notifier. This allows you to configure different notifiers for different OS if your
project is developed cross-platform or if you like to have local and remote notifications.
Notifications can also be turned off in the Guardfile, in addition to setting the environment variable GUARD_NOTIFY
or using the cli switch -n:
notification :off
interactor
You can customize the Pry interactor history and RC file like:
interactor guard_rc: '~/.my_guard-rc', history_file: '~/.my_guard_history_file'
If you do not need the Pry interactions with Guard at all, you can turn it off:
interactor :off
callback
The callback method allows you to execute arbitrary code before or after any of the start, stop, reload,
run_all, run_on_changes, run_on_additions, run_on_modifications and run_on_removals Guard plugins method.
You can even insert more hooks inside these methods.
guard :rspec do watch(%r{^spec/.+_spec\.rb$}) callback(:start_begin) { `mate .` } end
Please see the hooks and callbacks page in the Guard wiki for
more details.
ignore
The ignore method can be used to exclude files and directories from the set of files being watched. Let’s say you have
used the watch method to monitor a directory, but you are not interested in changes happening to images, you could use
the ignore method to exclude them.
This comes in handy when you have large amounts of non-source data in you project. By default
.rbx, .bundle, .DS_Store, .git, .hg ,.svn, bundle, log, tmp, vendor/bundle
are ignored.
Please note that method only accept regexps. See Listen README.
To append to the default ignored files and directories, use the ignore method:
ignore %r{^ignored/path/}, /public/
To replace any existing ignored files and directories, use the ignore! method:
ignore! /data/
filter
Alias of the ignore method.
logger
The logger method allows you to customize the Lumberjack log output to your
needs by specifying one or more options like:
logger level: :warn, template: '[:severity - :time - :progname] :message', time_format: 'at %I:%M%p', only: [:rspec, :jasmine, 'coffeescript'], except: :jammit, device: 'guard.log'
Log :level option must be either :debug, :info, :warn or :error. If Guard is started in debug mode, the log
level will be automatically set to :debug.
The :template option is a string which can have one or more of the following placeholders: :time, :severity,
:progname, :pid, :unit_of_work_id and :message. A unit of work is assigned for each action Guard performs on
multiple Guard plugin.
The :time_format option directives are the same as Time#strftime or can be :milliseconds
The :only and :except are either a string or a symbol, or an array of strings or symbols that matches the name of
the Guard plugin name that sends the log message. They cannot be specified at the same time.
By default the logger uses $stderr as device, but you can override this by supplying the :device option and set
either an IO stream or a filename.
Issues
Please check guard’s GitHub issue tracker for known issues. Additionally you should check listen’s issue tracker for issues which affect guard’s behaviour; for example, there is currently a nasty bug preventing listen from watching files inside symlinked directories.
File an issue
You can report bugs and feature requests to GitHub Issues.
Please don’t ask question in the issue tracker, instead ask them at one of our other places:
- Google+ community
- Google group
- StackOverflow
- IRC channel
#guard(irc.freenode.net) for chatting
Try to figure out where the issue belongs to: Is it an issue with Guard itself or with a Guard plugin you’re
using?
When you file a bug, please try to follow these simple rules if applicable:
- Make sure you’ve read the README carefully.
- Make sure you run Guard with
bundle execfirst. - Add debug information to the issue by running Guard with the
--debugoption. - Add your
GuardfileandGemfileto the issue. - Provide information about your environment:
- Your current versions of your OS, Ruby, Rubygems and Bundler.
- Shared project folder with services like Dropbox, NFS, etc.
- Make sure that the issue is reproducible with your description.
It’s most likely that your bug gets resolved faster if you provide as much information as possible!
Development
Pull requests are very welcome! Please try to follow these simple rules if applicable:
- Please create a topic branch for every separate change you make.
- Make sure your patches are well tested. All specs must pass on Travis CI.
- Update the Yard documentation.
- Update the README.
- Please do not change the version number.
For questions please join us in our Google group or on
#guard (irc.freenode.net).
Open Commit Bit
Guard has an open commit bit policy: Anyone with an accepted pull request gets added as a repository collaborator.
Please try to follow these simple rules:
- Commit directly onto the master branch only for typos, improvements to the readme and documentation (please add
[ci skip]to the commit message). - Create a feature branch and open a pull-request early for any new features to get feedback.
- Make sure you adhere to the general pull request rules above.
Author
Thibaud Guillaume-Gentil (@thibaudgg)
Core Team
- Michael Kessler (@netzpirat, mksoft.ch)
- Rémy Coutable (@rymai, rym.ai)
- Thibaud Guillaume-Gentil (@thibaudgg, thibaud.me)