bundle-update - Update your gems to the latest available versions
bundle update *gems [--source=NAME]
Update the gems specified (all gems, if none are specified), ignoring
the previously installed gems specified in the Gemfile.lock. In
general, you should use bundle install(1) to install the same exact
gems and versions across machines.
You would use bundle update to explicitly update the version of a
gem.
--source=<name>:git or :path source used in the Gemfile(5). For
instance, with a :git source of http://github.com/rails/rails.git,
you would call bundle update --source railsIf you run bundle update with no parameters, bundler will ignore
any previously installed gems and resolve all dependencies again
based on the latest versions of all gems available in the sources.
Consider the following Gemfile(5):
source "http://rubygems.org"
gem "rails", "3.0.0.rc"
gem "nokogiri"
When you run bundle install(1) the first time, bundler will resolve all of the dependencies, all the way down, and install what you need:
Fetching source index for http://rubygems.org/
Installing rake (10.0.2)
Installing abstract (1.0.0)
Installing activesupport (3.0.0.rc)
Installing builder (2.1.2)
Installing i18n (0.4.1)
Installing activemodel (3.0.0.rc)
Installing erubis (2.6.6)
Installing rack (1.2.1)
Installing rack-mount (0.6.9)
Installing rack-test (0.5.4)
Installing tzinfo (0.3.22)
Installing actionpack (3.0.0.rc)
Installing mime-types (1.16)
Installing polyglot (0.3.1)
Installing treetop (1.4.8)
Installing mail (2.2.5)
Installing actionmailer (3.0.0.rc)
Installing arel (0.4.0)
Installing activerecord (3.0.0.rc)
Installing activeresource (3.0.0.rc)
Installing bundler (1.0.0.rc.3)
Installing nokogiri (1.4.3.1) with native extensions
Installing thor (0.14.0)
Installing railties (3.0.0.rc)
Installing rails (3.0.0.rc)
Your bundle is complete! Use `bundle show [gemname]` to see where a bundled gem is installed.
As you can see, even though you have just two gems in the Gemfile(5), your application
actually needs 25 different gems in order to run. Bundler remembers the exact versions
it installed in Gemfile.lock. The next time you run bundle install(1), bundler skips
the dependency resolution and installs the same gems as it installed last time.
After checking in the Gemfile.lock into version control and cloning it on another
machine, running bundle install(1) will still install the gems that you installed
last time. You don't need to worry that a new release of erubis or mail changes
the gems you use.
However, from time to time, you might want to update the gems you are using to the newest versions that still match the gems in your Gemfile(5).
To do this, run bundle update, which will ignore the Gemfile.lock, and resolve
all the dependencies again. Keep in mind that this process can result in a significantly
different set of the 25 gems, based on the requirements of new gems that the gem
authors released since the last time you ran bundle update.
Sometimes, you want to update a single gem in the Gemfile(5), and leave the rest of the
gems that you specified locked to the versions in the Gemfile.lock.
For instance, in the scenario above, imagine that nokogiri releases version 1.4.4, and
you want to update it without updating Rails and all of its dependencies. To do this,
run bundle update nokogiri.
Bundler will update nokogiri and any of its dependencies, but leave alone Rails and
its dependencies.
Sometimes, multiple gems declared in your Gemfile(5) are satisfied by the same
second-level dependency. For instance, consider the case of thin and
rack-perftools-profiler.
source "http://rubygems.org"
gem "thin"
gem "rack-perftools-profiler"
The thin gem depends on rack >= 1.0, while rack-perftools-profiler depends
on rack ~> 1.0. If you run bundle install, you get:
Fetching source index for http://rubygems.org/
Installing daemons (1.1.0)
Installing eventmachine (0.12.10) with native extensions
Installing open4 (1.0.1)
Installing perftools.rb (0.4.7) with native extensions
Installing rack (1.2.1)
Installing rack-perftools_profiler (0.0.2)
Installing thin (1.2.7) with native extensions
Using bundler (1.0.0.rc.3)
In this case, the two gems have their own set of dependencies, but they share
rack in common. If you run bundle update thin, bundler will update daemons,
eventmachine and rack, which are dependencies of thin, but not open4 or
perftools.rb, which are dependencies of rack-perftools_profiler. Note that
bundle update thin will update rack even though it's also a dependency of
rack-perftools_profiler.
In short, when you update a gem using bundle update, bundler will update all
dependencies of that gem, including those that are also dependencies of another gem.
In this scenario, updating the thin version manually in the Gemfile(5),
and then running bundle install(1) will only update daemons and eventmachine,
but not rack. For more information, see the CONSERVATIVE UPDATING section
of bundle install(1).
In general, when working with an application managed with bundler, you should use the following workflow:
After you create your Gemfile(5) for the first time, run
$ bundle install
Check the resulting Gemfile.lock into version control
$ git add Gemfile.lock
When checking out this repository on another development machine, run
$ bundle install
When checking out this repository on a deployment machine, run
$ bundle install --deployment
After changing the Gemfile(5) to reflect a new or update dependency, run
$ bundle install
Make sure to check the updated Gemfile.lock into version control
$ git add Gemfile.lock
If bundle install(1) reports a conflict, manually update the specific gems that you changed in the Gemfile(5)
$ bundle update rails thin
If you want to update all the gems to the latest possible versions that still match the gems listed in the Gemfile(5), run
$ bundle update