BUNDLE-INSTALL(1) BUNDLE-INSTALL(1)

NAME

bundle-install - Install the dependencies specified in your Gemfile

SYNOPSIS

bundle install [--gemfile=GEMFILE]

                 [--path PATH] [--system]
                 [--without=GROUP1[ GROUP2...]]
                 [--local] [--deployment]
                 [--binstubs[=DIRECTORY]]
                 [--standalone[=GROUP1[ GROUP2...]]]
                 [--quiet]
                 [--no-cache]

DESCRIPTION

Install  the  gems  specified  in your Gemfile(5). If this is the first
time you run bundle  install  (and  a  Gemfile.lock  does  not  exist),
bundler will fetch all remote sources, resolve dependencies and install
all needed gems.

If a Gemfile.lock does exist, and you have not updated your Gemfile(5),
bundler  will fetch all remote sources, but use the dependencies speci-
fied in the Gemfile.lock instead of resolving dependencies.

If a Gemfile.lock does exist, and you  have  updated  your  Gemfile(5),
bundler will use the dependencies in the Gemfile.lock for all gems that
you did not update, but will re-resolve the dependencies of  gems  that
you did update. You can find more information about this update process
below under CONSERVATIVE UPDATING.

OPTIONS

--gemfile=<gemfile>
       The location of the Gemfile(5) that  bundler  should  use.  This
       defaults  to a gemfile in the current working directory. In gen-
       eral, bundler will assume that the location of the Gemfile(5) is
       also  the  project  root, and will look for the Gemfile.lock and
       vendor/cache relative to it.

--path=<path>
       The location to install the gems in the bundle to. This defaults
       to the gem home, which is the location that gem install installs
       gems to. This means that, by default, gems installed  without  a
       --path  setting  will  show  up  in  gem list. This setting is a
       remembered option.

--system
       Installs the gems in the bundle to  the  system  location.  This
       overrides any previous remembered use of --path.

--without=<list>
       A  space-separated  list of groups to skip installing. This is a
       remembered option.

--local
       Do not attempt to connect to rubygems.org,  instead  using  just
       the  gems already present in Rubygems' cache or in vendor/cache.
       Note that if a more appropriate platform-specific gem exists  on
       rubygems.org, it will not be found.

--deployment
       Switches  bundler's  defaults  into  deployment mode. Do not use
       this flag on development machines.

--binstubs[=<directory>]
       Create a directory (defaults to bin)  containing  an  executable
       that  runs  in  the  context of the bundle. For instance, if the
       rails gem comes with a rails executable, this flag will create a
       bin/rails  executable  that  ensures  that all dependencies used
       come from the bundled gems.

--shebang ruby-install-name
       Uses the ruby executable (usually ruby) provided to execute  the
       scripts created with --binstubs. For instance, if you use --bin-
       stubs with --shebang jruby, all executables will be  created  to
       use jruby instead.

--standalone[=<list>]
       Make a bundle that can work without Ruby Gems or Bundler at run-
       time. It takes a space separated list of groups to  install.  It
       creates  a  bundle  directory  and installs the bundle there. It
       also  generates  a  bundle/bundler/setup.rb  file   to   replace
       Bundler's own setup.

--no-cache
       Do  not  update the cache in vendor/cache with the newly bundled
       gems. This does not remove any existing cached gems, only  stops
       the newly bundled gems from being cached during the install.

DEPLOYMENT MODE

Bundler's defaults are optimized for development. To switch to defaults
optimized for deployment, use the --deployment flag.  Do  not  activate
deployment  mode  on development machines, as it will cause in an error
when the Gemfile is modified.

1.  A Gemfile.lock is required.

    To ensure that the same versions of the gems you developed with and
    tested  with  are  also  used  in  deployments,  a  Gemfile.lock is
    required.

    This is mainly to ensure that  you  remember  to  check  your  Gem-
    file.lock into version control.

2.  The Gemfile.lock must be up to date

    In  development,  you  can modify your Gemfile(5) and re-run bundle
    install to conservatively update your Gemfile.lock snapshot.

    In deployment, your Gemfile.lock should be up-to-date with  changes
    made in your Gemfile(5).

3.  Gems  are  installed to vendor/bundle not your default system loca-
    tion

    In development, it's convenient to share  the  gems  used  in  your
    application  with  other  applications and other scripts run on the
    system.

    In deployment, isolation is a more important default. In  addition,
    the  user  deploying  the  application  may  not have permission to
    install gems to the system, or the web server may not have  permis-
    sion to read them.

    As  a result, bundle install --deployment installs gems to the ven-
    dor/bundle directory in the application.  This  may  be  overridden
    using the --path option.

SUDO USAGE

By default, bundler installs gems to the same location as gem install.

In  some cases, that location may not be writable by your Unix user. In
that case, bundler will stage everything in a temporary directory, then
ask  you  for  your  sudo password in order to copy the gems into their
system location.

From your perspective,  this  is  identical  to  installing  them  gems
directly into the system.

You should never use sudo bundle install. This is because several other
steps in bundle install must be performed as the current user:

o   Updating your Gemfile.lock

o   Updating your vendor/cache, if necessary

o   Checking out private git repositories using your user's SSH keys

Of these three, the first  two  could  theoretically  be  performed  by
chowning  the  resulting  files  to $SUDO_USER. The third, however, can
only be performed by actually invoking the git command as  the  current
user.  Therefore,  git gems are downloaded and installed into ~/.bundle
rather than $GEM_HOME or $BUNDLE_PATH.

As a result, you should run bundle install as  the  current  user,  and
bundler will ask for your password if it is needed to put the gems into
their final location.

INSTALLING GROUPS

By default, bundle install will install all gems in all groups in  your
Gemfile(5), except those declared for a different platform.

However,  you  can  explicitly  tell bundler to skip installing certain
groups with the --without option. This option takes  a  space-separated
list of groups.

While  the --without option will skip installing the gems in the speci-
fied groups, it will still download those gems and use them to  resolve
the dependencies of every gem in your Gemfile(5).

This is so that installing a different set of groups on another machine
(such as a production server) will not change  the  gems  and  versions
that you have already developed and tested against.

Bundler offers a rock-solid guarantee that the third-party code you are
running in development and testing is also the third-party code you are
running  in  production. You can choose to exclude some of that code in
different environments, but you will never  be  caught  flat-footed  by
different versions of third-party code being used in different environ-
ments.

For a simple illustration, consider the following Gemfile(5):

    source "http://rubygems.org"

    gem "sinatra"

    group :production do
      gem "rack-perftools-profiler"
    end

In this case, sinatra depends on any version of  Rack  (>=  1.0,  while
rack-perftools-profiler depends on 1.x (~> 1.0).

When  you  run  bundle  install --without production in development, we
look at the dependencies of rack-perftools-profiler as well. That  way,
you  do  not spend all your time developing against Rack 2.0, using new
APIs unavailable in Rack 1.x, only to have bundler switch to  Rack  1.2
when the production group is used.

This  should  not  cause  any  problems  in practice, because we do not
attempt to install the gems in the excluded groups, and  only  evaluate
as part of the dependency resolution process.

This  also means that you cannot include different versions of the same
gem in different groups, because doing so  would  result  in  different
sets of dependencies used in development and production. Because of the
vagaries of the dependency resolution  process,  this  usually  affects
more  than just the gems you list in your Gemfile(5), and can (surpris-
ingly) radically change the gems you are using.

REMEMBERED OPTIONS

Some options (marked above  in  the  OPTIONS  section)  are  remembered
between calls to bundle install, and by the Bundler runtime.

For  instance,  if  you run bundle install --without test, a subsequent
call to bundle install that does not  include  a  --without  flag  will
remember your previous choice.

In  addition, a call to Bundler.setup will not attempt to make the gems
in those groups available on the Ruby  load  path,  as  they  were  not
installed.

The settings that are remembered are:

--deployment
       At  runtime, this remembered setting will also result in Bundler
       raising an exception if the Gemfile.lock is out of date.

--path Subsequent calls to bundle install  will  install  gems  to  the
       directory  originally passed to --path. The Bundler runtime will
       look for gems in that location. You can revert  this  option  by
       running bundle install --system.

--binstubs
       Bundler  will  update  the  executables every subsequent call to
       bundle install.

--without
       As described above, Bundler will  skip  the  gems  specified  by
       --without  in  subsequent  calls  to bundle install. The Bundler
       runtime will also not try to make the gems in the skipped groups
       available.

THE GEMFILE.LOCK

When  you  run  bundle install, Bundler will persist the full names and
versions of all gems that you used (including dependencies of the  gems
specified in the Gemfile(5)) into a file called Gemfile.lock.

Bundler uses this file in all subsequent calls to bundle install, which
guarantees that you always use the same exact code, even as your appli-
cation moves across machines.

Because  of the way dependency resolution works, even a seemingly small
change (for instance, an update to a point-release of a dependency of a
gem  in  your  Gemfile(5)) can result in radically different gems being
needed to satisfy all dependencies.

As a result, you SHOULD check your Gemfile.lock into  version  control.
If you do not, every machine that checks out your repository (including
your production server) will resolve all dependencies again, which will
result  in  different versions of third-party code being used if any of
the gems in the Gemfile(5) or  any  of  their  dependencies  have  been
updated.

CONSERVATIVE UPDATING

When  you  make a change to the Gemfile(5) and then run bundle install,
Bundler will update only the gems that you modified.

In other words, if a gem that you did  not  modify  worked  before  you
called  bundle install, it will continue to use the exact same versions
of all dependencies as it used before the update.

Let's take a look at an example. Here's your original Gemfile(5):

    source "http://rubygems.org"

    gem "actionpack", "2.3.8"
    gem "activemerchant"

In this case, both actionpack and activemerchant depend  on  activesup-
port.  The  actionpack  gem  depends on activesupport 2.3.8 and rack ~>
1.1.0, while the activemerchant gem depends on activesupport >=  2.3.2,
braintree >= 2.0.0, and builder >= 2.0.0.

When   the   dependencies  are  first  resolved,  Bundler  will  select
activesupport 2.3.8, which satisfies the requirements of both  gems  in
your Gemfile(5).

Next, you modify your Gemfile(5) to:

    source "http://rubygems.org"

    gem "actionpack", "3.0.0.rc"
    gem "activemerchant"

The  actionpack  3.0.0.rc  gem  has  a  number of new dependencies, and
updates the activesupport dependency to = 3.0.0.rc and the rack  depen-
dency to ~> 1.2.1.

When  you  run  bundle  install,  Bundler  notices that you changed the
actionpack gem, but not the activemerchant gem. It evaluates  the  gems
currently being used to satisfy its requirements:

activesupport 2.3.8
       also  used  to  satisfy a dependency in activemerchant, which is
       not being updated

rack ~> 1.1.0
       not currently being used to satify another dependency

Because you did not explicitly ask to update activemerchant, you  would
not  expect it to suddenly stop working after updating actionpack. How-
ever, satisfying the new activesupport 3.0.0.rc dependency  of  action-
pack requires updating one of its dependencies.

Even  though activemerchant declares a very loose dependency that theo-
retically matches activesupport 3.0.0.rc, bundler treats gems  in  your
Gemfile(5)  that have not changed as an atomic unit together with their
dependencies. In this case, the activemerchant dependency is treated as
activemerchant  1.7.1  +  activesupport  2.3.8,  so bundle install will
report that it cannot update actionpack.

To explicitly update actionpack, including its dependencies which other
gems  in  the  Gemfile(5) still depend on, run bundle update actionpack
(see bundle update(1)).

Summary: In general, after making a change  to  the  Gemfile(5)  ,  you
should  first  try  to run bundle install, which will guarantee that no
other gems in the Gemfile(5) are impacted by the change. If  that  does
not work, run bundle update(1) bundle-update.1.html.

                         September 2012               BUNDLE-INSTALL(1)