GEMFILE(5)																GEMFILE(5)

NAME

       Gemfile - A format for describing gem dependencies for Ruby programs

SYNOPSIS

       A Gemfile describes the gem dependencies required to execute associated Ruby code.

       Place  the  Gemfile in the root of the directory containing the associated code. For instance, in a Rails application, place the Gemfile in
       the same directory as the Rakefile.

SYNTAX

       A Gemfile is evaluated as Ruby code, in a context which makes available a number of methods used to describe the gem requirements.

SOURCES (#source)
       At the top of the Gemfile, add one line for each Rubygems source that might contain the gems listed in the Gemfile.

	   source "https://rubygems.org"
	   source "http://gems.github.com"

       Each of these _source_s MUST be a valid Rubygems repository. Sources are checked for gems following the heuristics described in SOURCE PRI-
       ORITY.

RUBY (#ruby)
       If  your  application requires a specific Ruby version or engine, specify your requirements using the ruby method, with the following argu-
       ments. All parameters are OPTIONAL unless otherwise specified.

   VERSION (required)
       The version of Ruby that your application requires. If your application requires an alternate Ruby engine, such as JRuby or Rubinius,  this
       should be the Ruby version that the engine is compatible with.

	   ruby "1.9.3"

   ENGINE (:engine)
       Each application may specify a Ruby engine. If an engine is specified, an engine version must also be specified.

   ENGINE VERSION (:engine_version)
       Each  application  may specify a Ruby engine version. If an engine version is specified, an engine must also be specified. If the engine is
       "ruby" the engine version specified must match the Ruby version.

	   ruby "1.8.7", :engine => "jruby", :engine_version => "1.6.7"

GEMS (#gem)
       Specify gem requirements using the gem method, with the following arguments. All parameters are OPTIONAL unless otherwise specified.

   NAME (required)
       For each gem requirement, list a single gem line.

	   gem "nokogiri"

   VERSION
       Each gem MAY have one or more version specifiers.

	   gem "nokogiri", ">= 1.4.2"
	   gem "RedCloth", ">= 4.1.0", "< 4.2.0"

   REQUIRE AS (:require)
       Each gem MAY specify files that should be used when autorequiring via Bundler.require. You may pass an array with multiple files, or  false
       to prevent any file from being autorequired.

	   gem "redis", :require => ["redis/connection/hiredis", "redis"]
	   gem "webmock", :require => false

       The argument defaults to the name of the gem. For example, these are identical:

	   gem "nokogiri"
	   gem "nokogiri", :require => "nokogiri"

   GROUPS (:group or :groups)
       Each  gem  MAY  specify	membership  in	one or more groups. Any gem that does not specify membership in any group is placed in the default
       group.

	   gem "rspec", :group => :test
	   gem "wirble", :groups => [:development, :test]

       The Bundler runtime allows its two main methods, Bundler.setup and Bundler.require, to limit their impact to particular groups.

	   # setup adds gems to Ruby's load path
	   Bundler.setup		    # defaults to all groups
	   require "bundler/setup"	    # same as Bundler.setup
	   Bundler.setup(:default)	    # only set up the _default_ group
	   Bundler.setup(:test) 	    # only set up the _test_ group (but `not` _default_)
	   Bundler.setup(:default, :test)   # set up the _default_ and _test_ groups, but no others

	   # require requires all of the gems in the specified groups
	   Bundler.require		    # defaults to just the _default_ group
	   Bundler.require(:default)	    # identical
	   Bundler.require(:default, :test) # requires the _default_ and _test_ groups
	   Bundler.require(:test)	    # requires just the _test_ group

       The Bundler CLI allows you to specify a list of groups whose gems bundle install should not install with the --without option.  To  specify
       multiple groups to ignore, specify a list of groups separated by spaces.

	   bundle install --without test
	   bundle install --without development test

       After running bundle install --without test, bundler will remember that you excluded the test group in the last installation. The next time
       you run bundle install, without any --without option, bundler will recall it.

       Also, calling Bundler.setup with no parameters, or calling require "bundler/setup" will setup all groups except for the ones  you  excluded
       via --without (since they are obviously not available).

       Note  that  on  bundle install, bundler downloads and evaluates all gems, in order to create a single canonical list of all of the required
       gems and their dependencies. This means that you cannot list different versions of the same gems in different groups. For more details, see
       Understanding Bundler http://gembundler.com/rationale.html.

   PLATFORMS (:platforms)
       If  a  gem  should  only be used in a particular platform or set of platforms, you can specify them. Platforms are essentially identical to
       groups, except that you do not need to use the --without install-time flag to exclude groups of gems for other platforms.

       There are a number of Gemfile platforms:

       ruby   C Ruby (MRI) or Rubinius, but NOT Windows

       ruby_18
	      ruby AND version 1.8

       ruby_19
	      ruby AND version 1.9

       ruby_20
	      ruby AND version 2.0

       mri    Same as ruby, but not Rubinius

       mri_18 mri AND version 1.8

       mri_19 mri AND version 1.9

       mri_20 mri AND version 2.0

       rbx    Same as ruby, but only Rubinius (not MRI)

       jruby  JRuby

       mswin  Windows

       mingw  Windows 'mingw32' platform (aka RubyInstaller)

       mingw_18
	      mingw AND version 1.8

       mingw_19
	      mingw AND version 1.9

       mingw_20
	      mingw AND version 2.0

       As with groups, you can specify one or more platforms:

	   gem "weakling",   :platforms => :jruby
	   gem "ruby-debug", :platforms => :mri_18
	   gem "nokogiri",   :platforms => [:mri_18, :jruby]

       All operations involving groups (bundle install, Bundler.setup, Bundler.require) behave exactly the same as if any groups not matching  the
       current platform were explicitly excluded.

   GIT (:git)
       If   necessary,	 you   can   specify   that   a   gem	is  located  at  a  particular	git  repository.  The  repository  can	be  public
       (http://github.com/rails/rails.git) or private (git@github.com:rails/rails.git). If the repository is private, the user that you use to run
       bundle install MUST have the appropriate keys available in their $HOME/.ssh.

       Git  repositories  are  specified  using the :git parameter. The group, platforms, and require options are available and behave exactly the
       same as they would for a normal gem.

	   gem "rails", :git => "git://github.com/rails/rails.git"

       A git repository SHOULD have at least one file, at the root of the directory containing the gem, with the  extension  .gemspec.	This  file
       MUST contain a valid gem specification, as expected by the gem build command. It MUST NOT have any dependencies, other than on the files in
       the git repository itself and any built-in functionality of Ruby or Rubygems.

       If a git repository does not have a .gemspec, bundler will attempt to create one, but it will not contain any dependencies, executables, or
       C extension compilation instructions. As a result, it may fail to properly integrate into your application.

       If a git repository does have a .gemspec for the gem you attached it to, a version specifier, if provided, means that the git repository is
       only valid if the .gemspec specifies a version matching the version specifier. If not, bundler will print a warning.

	   gem "rails", "2.3.8", :git => "git://github.com/rails/rails.git"
	   # bundle install will fail, because the .gemspec in the rails
	   # repository's master branch specifies version 3.0.0

       If a git repository does not have a .gemspec for the gem you attached it to, a version specifier MUST be provided. Bundler  will  use  this
       version in the simple .gemspec it creates.

       Git repositories support a number of additional options.

       branch, tag, and ref
	      You MUST only specify at most one of these options. The default is :branch => "master"

       submodules
	      Specify :submodules => true to cause bundler to expand any submodules included in the git repository

       If  a  git repository contains multiple .gemspecs, each .gemspec represents a gem located at the same place in the file system as the .gem-
       spec.

	   |~rails		     [git root]
	   | |-rails.gemspec	     [rails gem located here]
	   |~actionpack
	   | |-actionpack.gemspec    [actionpack gem located here]
	   |~activesupport
	   | |-activesupport.gemspec [activesupport gem located here]
	   |...

       To install a gem located in a git repository, bundler changes to the directory containing the gemspec, runs gem build name.gemspec and then
       installs  the resulting gem. The gem build command, which comes standard with Rubygems, evaluates the .gemspec in the context of the direc-
       tory in which it is located.

   GITHUB (:github)
       If the git repository you want to use is hosted on GitHub and is public, you can use the :github shorthand to specify just the github user-
       name  and  repository  name (without the trailing ".git"), separated by a slash. If both the username and repository name are the same, you
       can omit one.

	   gem "rails", :github => "rails/rails"
	   gem "rails", :github => "rails"

       Are both equivalent to

	   gem "rails", :git => "git://github.com/rails/rails.git"

   PATH (:path)
       You can specify that a gem is located in a particular location on the file system. Relative paths are resolved relative	to  the  directory
       containing the Gemfile.

       Similar	to  the  semantics of the :git option, the :path option requires that the directory in question either contains a .gemspec for the
       gem, or that you specify an explicit version that bundler should use.

       Unlike :git, bundler does not compile C extensions for gems specified as paths.

	   gem "rails", :path => "vendor/rails"

BLOCK FORM OF GIT, PATH, GROUP and PLATFORMS
       The :git, :path, :group, and :platforms options may be applied to a group of gems by using block form.

	   git "git://github.com/rails/rails.git" do
	     gem "activesupport"
	     gem "actionpack"
	   end

	   platforms :ruby do
	     gem "ruby-debug"
	     gem "sqlite3"
	   end

	   group :development do
	     gem "wirble"
	     gem "faker"
	   end

       In the case of the git block form, the :ref, :branch, :tag, and :submodules options may be passed to the git method, and all  gems  in  the
       block will inherit those options.

GEMSPEC (#gemspec)
       If you wish to use Bundler to help install dependencies for a gem while it is being developed, use the gemspec method to pull in the depen-
       dencies listed in the .gemspec file.

       The gemspec method adds any runtime dependencies as gem requirements in the default group. It also adds	development  dependencies  as  gem
       requirements  in the development group. Finally, it adds a gem requirement on your project (:path => '.'). In conjunction with Bundler.set-
       up, this allows you to require project files in your test code as you would if the project were installed as a gem; you need not manipulate
       the load path manually or require project files via relative paths.

       The gemspec method supports optional :path, :name, and :development_group options, which control where bundler looks for the .gemspec, what
       named .gemspec it uses (if more than one is present), and which group development dependencies are included in.

SOURCE PRIORITY

       When attempting to locate a gem to satisfy a gem requirement, bundler uses the following priority order:

       1.  The source explicitly attached to the gem (using :path or :git)

       2.  For implicit gems (dependencies of explicit gems), any git or path repository otherwise declared. This results in bundler  prioritizing
	   the ActiveSupport gem from the Rails git repository over ones from rubygems.org

       3.  The sources specified via source, searching each source in your Gemfile from last added to first added.

								    March 2013								GEMFILE(5)