1GEMFILE(5) GEMFILE(5)
2
6 Gemfile - A format for describing gem dependencies for Ruby programs
7
9 A Gemfile describes the gem dependencies required to execute associated
10 Ruby code.
11 Place the Gemfile in the root of the directory containing the associ‐
13 ated code. For instance, in a Rails application, place the Gemfile in
14 the same directory as the Rakefile.
15
17 A Gemfile is evaluated as Ruby code, in a context which makes available
18 a number of methods used to describe the gem requirements.
19
21 At the top of the Gemfile, add a line for the Rubygems source that con‐
22 tains the gems listed in the Gemfile.
23 source "https://rubygems.org"
27 It is possible, but not recommended as of Bundler 1.7, to add multiple
31 global source lines. Each of these sources MUST be a valid Rubygems
32 repository.
33 Sources are checked for gems following the heuristics described in
35 SOURCE PRIORITY. If a gem is found in more than one global source,
36 Bundler will print a warning after installing the gem indicating which
37 source was used, and listing the other sources where the gem is avail‐
38 able. A specific source can be selected for gems that need to use a
39 non-standard repository, suppressing this warning, by using the :source
40 option or a source block.
41 CREDENTIALS
43 Some gem sources require a username and password. Use bundle config(1)
44 bundle-config.1.html to set the username and password for any of the
45 sources that need it. The command must be run once on each computer
46 that will install the Gemfile, but this keeps the credentials from be‐
47 ing stored in plain text in version control.
48 bundle config gems.example.com user:password
52 For some sources, like a company Gemfury account, it may be easier to
56 include the credentials in the Gemfile as part of the source URL.
57 source "https://user:password@gems.example.com"
61 Credentials in the source URL will take precedence over credentials set
65 using config.
66
68 If your application requires a specific Ruby version or engine, specify
69 your requirements using the ruby method, with the following arguments.
70 All parameters are OPTIONAL unless otherwise specified.
71 VERSION (required)
73 The version of Ruby that your application requires. If your application
74 requires an alternate Ruby engine, such as JRuby, Rubinius or Truf‐
75 fleRuby, this should be the Ruby version that the engine is compatible
76 with.
77 ruby "1.9.3"
81 ENGINE
85 Each application may specify a Ruby engine. If an engine is specified,
86 an engine version must also be specified.
87 What exactly is an Engine? - A Ruby engine is an implementation of the
89 Ruby language.
90 • For background: the reference or original implementation of the
92 Ruby programming language is called Matz´s Ruby Interpreter
93 https://en.wikipedia.org/wiki/Ruby_MRI, or MRI for short. This is
94 named after Ruby creator Yukihiro Matsumoto, also known as Matz.
95 MRI is also known as CRuby, because it is written in C. MRI is the
96 most widely used Ruby engine.
97 • Other implementations https://www.ruby-lang.org/en/about/ of Ruby
99 exist. Some of the more well-known implementations include Rubinius
100 https://rubinius.com/, and JRuby http://jruby.org/. Rubinius is an
101 alternative implementation of Ruby written in Ruby. JRuby is an im‐
102 plementation of Ruby on the JVM, short for Java Virtual Machine.
103 ENGINE VERSION
107 Each application may specify a Ruby engine version. If an engine ver‐
108 sion is specified, an engine must also be specified. If the engine is
109 "ruby" the engine version specified must match the Ruby version.
110 ruby "1.8.7", :engine => "jruby", :engine_version => "1.6.7"
114 PATCHLEVEL
118 Each application may specify a Ruby patchlevel.
119 ruby "2.0.0", :patchlevel => "247"
123
127 Specify gem requirements using the gem method, with the following argu‐
128 ments. All parameters are OPTIONAL unless otherwise specified.
129 NAME (required)
131 For each gem requirement, list a single gem line.
132 gem "nokogiri"
136 VERSION
140 Each gem MAY have one or more version specifiers.
141 gem "nokogiri", ">= 1.4.2"
145 gem "RedCloth", ">= 4.1.0", "< 4.2.0"
146 REQUIRE AS
150 Each gem MAY specify files that should be used when autorequiring via
151 Bundler.require. You may pass an array with multiple files or true if
152 the file you want required has the same name as gem or false to prevent
153 any file from being autorequired.
154 gem "redis", :require => ["redis/connection/hiredis", "redis"]
158 gem "webmock", :require => false
159 gem "byebug", :require => true
160 The argument defaults to the name of the gem. For example, these are
164 identical:
165 gem "nokogiri"
169 gem "nokogiri", :require => "nokogiri"
170 gem "nokogiri", :require => true
171 GROUPS
175 Each gem MAY specify membership in one or more groups. Any gem that
176 does not specify membership in any group is placed in the default
177 group.
178 gem "rspec", :group => :test
182 gem "wirble", :groups => [:development, :test]
183 The Bundler runtime allows its two main methods, Bundler.setup and
187 Bundler.require, to limit their impact to particular groups.
188 # setup adds gems to Ruby´s load path
192 Bundler.setup # defaults to all groups
193 require "bundler/setup" # same as Bundler.setup
194 Bundler.setup(:default) # only set up the _default_ group
195 Bundler.setup(:test) # only set up the _test_ group (but `not` _default_)
196 Bundler.setup(:default, :test) # set up the _default_ and _test_ groups, but no others
197 # require requires all of the gems in the specified groups
199 Bundler.require # defaults to the _default_ group
200 Bundler.require(:default) # identical
201 Bundler.require(:default, :test) # requires the _default_ and _test_ groups
202 Bundler.require(:test) # requires the _test_ group
203 The Bundler CLI allows you to specify a list of groups whose gems bun‐
207 dle install should not install with the without configuration.
208 To specify multiple groups to ignore, specify a list of groups sepa‐
210 rated by spaces.
211 bundle config set --local without test
215 bundle config set --local without development test
216 Also, calling Bundler.setup with no parameters, or calling require
220 "bundler/setup" will setup all groups except for the ones you excluded
221 via --without (since they are not available).
222 Note that on bundle install, bundler downloads and evaluates all gems,
224 in order to create a single canonical list of all of the required gems
225 and their dependencies. This means that you cannot list different ver‐
226 sions of the same gems in different groups. For more details, see Un‐
227 derstanding Bundler https://bundler.io/rationale.html.
228 PLATFORMS
230 If a gem should only be used in a particular platform or set of plat‐
231 forms, you can specify them. Platforms are essentially identical to
232 groups, except that you do not need to use the --without install-time
233 flag to exclude groups of gems for other platforms.
234 There are a number of Gemfile platforms:
236 ruby C Ruby (MRI), Rubinius or TruffleRuby, but NOT Windows
238 mri Same as ruby, but only C Ruby (MRI)
240 mingw Windows 32 bit ´mingw32´ platform (aka RubyInstaller)
242 x64_mingw
244 Windows 64 bit ´mingw32´ platform (aka RubyInstaller x64)
245 rbx Rubinius
247 jruby JRuby
249 truffleruby
251 TruffleRuby
252 mswin Windows
254 You can restrict further by platform and version for all platforms ex‐
256 cept for rbx, jruby, truffleruby and mswin.
257 To specify a version in addition to a platform, append the version num‐
259 ber without the delimiter to the platform. For example, to specify that
260 a gem should only be used on platforms with Ruby 2.3, use:
261 ruby_23
265 The full list of platforms and supported versions includes:
269 ruby 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
271 mri 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
273 mingw 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
275 x64_mingw
277 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6
278 As with groups, you can specify one or more platforms:
280 gem "weakling", :platforms => :jruby
284 gem "ruby-debug", :platforms => :mri_18
285 gem "nokogiri", :platforms => [:mri_18, :jruby]
286 All operations involving groups (bundle install bundle-install.1.html,
290 Bundler.setup, Bundler.require) behave exactly the same as if any
291 groups not matching the current platform were explicitly excluded.
292 SOURCE
294 You can select an alternate Rubygems repository for a gem using the
295 ´:source´ option.
296 gem "some_internal_gem", :source => "https://gems.example.com"
300 This forces the gem to be loaded from this source and ignores any
304 global sources declared at the top level of the file. If the gem does
305 not exist in this source, it will not be installed.
306 Bundler will search for child dependencies of this gem by first looking
308 in the source selected for the parent, but if they are not found there,
309 it will fall back on global sources using the ordering described in
310 SOURCE PRIORITY.
311 Selecting a specific source repository this way also suppresses the am‐
313 biguous gem warning described above in GLOBAL SOURCES (#source).
314 Using the :source option for an individual gem will also make that
316 source available as a possible global source for any other gems which
317 do not specify explicit sources. Thus, when adding gems with explicit
318 sources, it is recommended that you also ensure all other gems in the
319 Gemfile are using explicit sources.
320 GIT
322 If necessary, you can specify that a gem is located at a particular git
323 repository using the :git parameter. The repository can be accessed via
324 several protocols:
325 HTTP(S)
327 gem "rails", :git => "https://github.com/rails/rails.git"
328 SSH gem "rails", :git => "git@github.com:rails/rails.git"
330 git gem "rails", :git => "git://github.com/rails/rails.git"
332 If using SSH, the user that you use to run bundle install MUST have the
334 appropriate keys available in their $HOME/.ssh.
335 NOTE: http:// and git:// URLs should be avoided if at all possible.
337 These protocols are unauthenticated, so a man-in-the-middle attacker
338 can deliver malicious code and compromise your system. HTTPS and SSH
339 are strongly preferred.
340 The group, platforms, and require options are available and behave ex‐
342 actly the same as they would for a normal gem.
343 A git repository SHOULD have at least one file, at the root of the di‐
345 rectory containing the gem, with the extension .gemspec. This file MUST
346 contain a valid gem specification, as expected by the gem build com‐
347 mand.
348 If a git repository does not have a .gemspec, bundler will attempt to
350 create one, but it will not contain any dependencies, executables, or C
351 extension compilation instructions. As a result, it may fail to prop‐
352 erly integrate into your application.
353 If a git repository does have a .gemspec for the gem you attached it
355 to, a version specifier, if provided, means that the git repository is
356 only valid if the .gemspec specifies a version matching the version
357 specifier. If not, bundler will print a warning.
358 gem "rails", "2.3.8", :git => "https://github.com/rails/rails.git"
362 # bundle install will fail, because the .gemspec in the rails
363 # repository´s master branch specifies version 3.0.0
364 If a git repository does not have a .gemspec for the gem you attached
368 it to, a version specifier MUST be provided. Bundler will use this ver‐
369 sion in the simple .gemspec it creates.
370 Git repositories support a number of additional options.
372 branch, tag, and ref
374 You MUST only specify at most one of these options. The default
375 is :branch => "master". For example:
376 gem "rails", :git => "https://github.com/rails/rails.git",
378 :branch => "5-0-stable"
379 gem "rails", :git => "https://github.com/rails/rails.git", :tag
381 => "v5.0.0"
382 gem "rails", :git => "https://github.com/rails/rails.git", :ref
384 => "4aded"
385 submodules
387 For reference, a git submodule
388 https://git-scm.com/book/en/v2/Git-Tools-Submodules lets you
389 have another git repository within a subfolder of your reposi‐
390 tory. Specify :submodules => true to cause bundler to expand any
391 submodules included in the git repository
392 If a git repository contains multiple .gemspecs, each .gemspec repre‐
394 sents a gem located at the same place in the file system as the .gem‐
395 spec.
396 |~rails [git root]
400 | |-rails.gemspec [rails gem located here]
401 |~actionpack
402 | |-actionpack.gemspec [actionpack gem located here]
403 |~activesupport
404 | |-activesupport.gemspec [activesupport gem located here]
405 |...
406 To install a gem located in a git repository, bundler changes to the
410 directory containing the gemspec, runs gem build name.gemspec and then
411 installs the resulting gem. The gem build command, which comes standard
412 with Rubygems, evaluates the .gemspec in the context of the directory
413 in which it is located.
414 GIT SOURCE
416 A custom git source can be defined via the git_source method. Provide
417 the source´s name as an argument, and a block which receives a single
418 argument and interpolates it into a string to return the full repo ad‐
419 dress:
420 git_source(:stash){ |repo_name| "https://stash.corp.acme.pl/#{repo_name}.git" }
424 gem ´rails´, :stash => ´forks/rails´
425 In addition, if you wish to choose a specific branch:
429 gem "rails", :stash => "forks/rails", :branch => "branch_name"
433 GITHUB
437 NOTE: This shorthand should be avoided until Bundler 2.0, since it cur‐
438 rently expands to an insecure git:// URL. This allows a man-in-the-mid‐
439 dle attacker to compromise your system.
440 If the git repository you want to use is hosted on GitHub and is pub‐
442 lic, you can use the :github shorthand to specify the github username
443 and repository name (without the trailing ".git"), separated by a
444 slash. If both the username and repository name are the same, you can
445 omit one.
446 gem "rails", :github => "rails/rails"
450 gem "rails", :github => "rails"
451 Are both equivalent to
455 gem "rails", :git => "git://github.com/rails/rails.git"
459 Since the github method is a specialization of git_source, it accepts a
463 :branch named argument.
464 GIST
466 If the git repository you want to use is hosted as a Github Gist and is
467 public, you can use the :gist shorthand to specify the gist identifier
468 (without the trailing ".git").
469 gem "the_hatch", :gist => "4815162342"
473 Is equivalent to:
477 gem "the_hatch", :git => "https://gist.github.com/4815162342.git"
481 Since the gist method is a specialization of git_source, it accepts a
485 :branch named argument.
486 BITBUCKET
488 If the git repository you want to use is hosted on Bitbucket and is
489 public, you can use the :bitbucket shorthand to specify the bitbucket
490 username and repository name (without the trailing ".git"), separated
491 by a slash. If both the username and repository name are the same, you
492 can omit one.
493 gem "rails", :bitbucket => "rails/rails"
497 gem "rails", :bitbucket => "rails"
498 Are both equivalent to
502 gem "rails", :git => "https://rails@bitbucket.org/rails/rails.git"
506 Since the bitbucket method is a specialization of git_source, it ac‐
510 cepts a :branch named argument.
511 PATH
513 You can specify that a gem is located in a particular location on the
514 file system. Relative paths are resolved relative to the directory con‐
515 taining the Gemfile.
516 Similar to the semantics of the :git option, the :path option requires
518 that the directory in question either contains a .gemspec for the gem,
519 or that you specify an explicit version that bundler should use.
520 Unlike :git, bundler does not compile C extensions for gems specified
522 as paths.
523 gem "rails", :path => "vendor/rails"
527 If you would like to use multiple local gems directly from the filesys‐
531 tem, you can set a global path option to the path containing the gem´s
532 files. This will automatically load gemspec files from subdirectories.
533 path ´components´ do
537 gem ´admin_ui´
538 gem ´public_ui´
539 end
540
544 The :source, :git, :path, :group, and :platforms options may be applied
545 to a group of gems by using block form.
546 source "https://gems.example.com" do
550 gem "some_internal_gem"
551 gem "another_internal_gem"
552 end
553 git "https://github.com/rails/rails.git" do
555 gem "activesupport"
556 gem "actionpack"
557 end
558 platforms :ruby do
560 gem "ruby-debug"
561 gem "sqlite3"
562 end
563 group :development, :optional => true do
565 gem "wirble"
566 gem "faker"
567 end
568 In the case of the group block form the :optional option can be given
572 to prevent a group from being installed unless listed in the --with op‐
573 tion given to the bundle install command.
574 In the case of the git block form, the :ref, :branch, :tag, and :sub‐
576 modules options may be passed to the git method, and all gems in the
577 block will inherit those options.
578 The presence of a source block in a Gemfile also makes that source
580 available as a possible global source for any other gems which do not
581 specify explicit sources. Thus, when defining source blocks, it is rec‐
582 ommended that you also ensure all other gems in the Gemfile are using
583 explicit sources, either via source blocks or :source directives on in‐
584 dividual gems.
585
587 The install_if method allows gems to be installed based on a proc or
588 lambda. This is especially useful for optional gems that can only be
589 used if certain software is installed or some other conditions are met.
590 install_if -> { RUBY_PLATFORM =~ /darwin/ } do
594 gem "pasteboard"
595 end
596
600 The .gemspec http://guides.rubygems.org/specification-reference/ file
601 is where you provide metadata about your gem to Rubygems. Some required
602 Gemspec attributes include the name, description, and homepage of your
603 gem. This is also where you specify the dependencies your gem needs to
604 run.
605 If you wish to use Bundler to help install dependencies for a gem while
607 it is being developed, use the gemspec method to pull in the dependen‐
608 cies listed in the .gemspec file.
609 The gemspec method adds any runtime dependencies as gem requirements in
611 the default group. It also adds development dependencies as gem re‐
612 quirements in the development group. Finally, it adds a gem requirement
613 on your project (:path => ´.´). In conjunction with Bundler.setup, this
614 allows you to require project files in your test code as you would if
615 the project were installed as a gem; you need not manipulate the load
616 path manually or require project files via relative paths.
617 The gemspec method supports optional :path, :glob, :name, and :develop‐
619 ment_group options, which control where bundler looks for the .gemspec,
620 the glob it uses to look for the gemspec (defaults to: "{,,/*}.gem‐
621 spec"), what named .gemspec it uses (if more than one is present), and
622 which group development dependencies are included in.
623 When a gemspec dependency encounters version conflicts during resolu‐
625 tion, the local version under development will always be selected --
626 even if there are remote versions that better match other requirements
627 for the gemspec gem.
628
630 When attempting to locate a gem to satisfy a gem requirement, bundler
631 uses the following priority order:
632 1. The source explicitly attached to the gem (using :source, :path, or
634 :git)
635 2. For implicit gems (dependencies of explicit gems), any source, git,
637 or path repository declared on the parent. This results in bundler
638 prioritizing the ActiveSupport gem from the Rails git repository
639 over ones from rubygems.org
640 3. The sources specified via global source lines, searching each
642 source in your Gemfile from last added to first added.
643 June 2021 GEMFILE(5)