bundle-config(1) -- Set bundler configuration options
=====================================================

## SYNOPSIS

`bundle config` [<name> [<value>]]

## DESCRIPTION

This command allows you to interact with bundler's configuration system.
Bundler retrieves its configuration from the local application (`app/.bundle/config`),
environment variables, and the user's home directory (`~/.bundle/config`),
in that order of priority.

Executing `bundle config` with no parameters will print a list of all
bundler configuration for the current bundle, and where that configuration
was set.

Executing `bundle config <name>` will print the value of that configuration
setting, and where it was set.

Executing `bundle config <name> <value>` will set that configuration to the
value specified for all bundles executed as the current user. The configuration
will be stored in `~/.bundle/config`. If <name> already is set, <name> will be
overridden and user will be warned.

Executing `bundle config --global <name> <value>` works the same as above.

Executing `bundle config --local <name> <value>` will set that configuration to
the local application. The configuration will be stored in `app/.bundle/config`.

Executing `bundle config --delete <name>` will delete the configuration in both
local and global sources. Not compatible with --global or --local flag.

Executing bundle with the `BUNDLE_IGNORE_CONFIG` environment variable set will
cause it to ignore all configuration.

## BUILD OPTIONS

You can use `bundle config` to give bundler the flags to pass to the gem
installer every time bundler tries to install a particular gem.

A very common example, the `mysql` gem, requires Snow Leopard users to
pass configuration flags to `gem install` to specify where to find the
`mysql_config` executable.

    gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config

Since the specific location of that executable can change from machine
to machine, you can specify these flags on a per-machine basis.

    bundle config build.mysql --with-mysql-config=/usr/local/mysql/bin/mysql_config

After running this command, every time bundler needs to install the
`mysql` gem, it will pass along the flags you specified.

## CONFIGURATION KEYS

Configuration keys in bundler have two forms: the canonical form and the
environment variable form.

For instance, passing the `--without` flag to [bundle install(1)][bundle-install]
prevents Bundler from installing certain groups specified in the Gemfile(5). Bundler
persists this value in `app/.bundle/config` so that calls to `Bundler.setup`
do not try to find gems from the `Gemfile` that you didn't install. Additionally,
subsequent calls to [bundle install(1)][bundle-install] remember this setting and skip those
groups.

The canonical form of this configuration is `"without"`. To convert the canonical
form to the environment variable form, capitalize it, and prepend `BUNDLE_`. The
environment variable form of `"without"` is `BUNDLE_WITHOUT`.

## LIST OF AVAILABLE KEYS

The following is a list of all configuration keys and their purpose. You can
learn more about their operation in [bundle install(1)][bundle-install].

* `path` (`BUNDLE_PATH`):
  The location on disk to install gems. Defaults to `$GEM_HOME` in development
  and `vendor/bundler` when `--deployment` is used
* `frozen` (`BUNDLE_FROZEN`):
  Disallow changes to the `Gemfile`. Defaults to `true` when `--deployment`
  is used.
* `without` (`BUNDLE_WITHOUT`):
  A `:`-separated list of groups whose gems bundler should not install
* `bin` (`BUNDLE_BIN`):
  Install executables from gems in the bundle to the specified directory.
  Defaults to `false`.
* `gemfile` (`BUNDLE_GEMFILE`):
  The name of the file that bundler should use as the `Gemfile`. This location
  of this file also sets the root of the project, which is used to resolve
  relative paths in the `Gemfile`, among other things. By default, bundler
  will search up from the current working directory until it finds a
  `Gemfile`.

In general, you should set these settings per-application by using the applicable
flag to the [bundle install(1)][bundle-install] command.

You can set them globally either via environment variables or `bundle config`,
whichever is preferable for your setup. If you use both, environment variables
will take preference over global settings.

## LOCAL GIT REPOS

Bundler also allows you to work against a git repository locally
instead of using the remote version. This can be achieved by setting
up a local override:

    bundle config local.GEM_NAME /path/to/local/git/repository

For example, in order to use a local Rack repository, a developer could call:

    bundle config local.rack ~/Work/git/rack

Now instead of checking out the remote git repository, the local
override will be used. Similar to a path source, every time the local
git repository change, changes will be automatically picked up by
Bundler. This means a commit in the local git repo will update the
revision in the `Gemfile.lock` to the local git repo revision. This
requires the same attention as git submodules. Before pushing to
the remote, you need to ensure the local override was pushed, otherwise
you may point to a commit that only exists in your local machine.

Bundler does many checks to ensure a developer won't work with
invalid references. Particularly, we force a developer to specify
a branch in the `Gemfile` in order to use this feature. If the branch
specified in the `Gemfile` and the current branch in the local git
repository do not match, Bundler will abort. This ensures that
a developer is always working against the correct branches, and prevents
accidental locking to a different branch.

Finally, Bundler also ensures that the current revision in the
`Gemfile.lock` exists in the local git repository. By doing this, Bundler
forces you to fetch the latest changes in the remotes.
