Where is gemfile in rails

When you specify a gem without version on the Gemfile, Bundler will try to install the gems with the latest version based on its dependencies. RubyGems suggests a versioning convention for the Gems as follows:. Patch — 0.

X — Includes bug fixes, All the features worked on v0. Minor — 0. Major — X. Bundler will increment the last digit of the specified version to identify the range of versions applicable for installation. We need to require a dependency in another file in order to use the code inside it. Ruby provides a commonly used method called require which allows us to execute the code from another file. The require method allows the file to be executed only once. When you launch irb and require the above file, ruby will execute the code inside it and returns true.

If you require the same file again, code inside the file will never get executed and require method will return false. When you require a file with an absolute path, it will look for the file on the given path, execute the code inside it. Bundler uses the same process for requiring the gems. During the initialisation process of Rails app bundler loads boot. Credentials in the source URL will take precedence over credentials set using config. Declare the gems that you need, including version numbers.

Specify versions using the same syntax that RubyGems supports for dependencies. If a gem's main file is different than the gem name, specify how to require it. In order to require gems in your Gemfile , you will need to call Bundler. If some of your gems need to be fetched from a private gem server, this default source can be overridden for those gems. For a gem server that contains a single gem, it is easiest to use the :source option on that gem. If several gems come from the same server, you can use a source block to group them together.

Credentials for gem servers can be specified either in the URL or using bundle config , as described above. Git repositories are also valid gem sources, as long as the repo contains one or more valid gems. Specify what to check out with :tag , :branch , or :ref. For instance, in a Rails application, place the Gemfile in the same directory as the Rakefile.

A Gemfile is evaluated as Ruby code, in a context which makes available a number of methods used to describe the gem requirements. At the top of the Gemfile , add a line for the Rubygems source that contains the gems listed in the Gemfile. It is possible, but not recommended as of Bundler 1.

If a gem is found in more than one global source, Bundler will print a warning after installing the gem indicating which source was used, and listing the other sources where the gem is available. A specific source can be selected for gems that need to use a non-standard repository, suppressing this warning, by using the :source option or a source block.

Some gem sources require a username and password. Use bundle config 1 to set the username and password for any of the sources that need it. The command must be run once on each computer that will install the Gemfile, but this keeps the credentials from being stored in plain text in version control.

For some sources, like a company Gemfury account, it may be easier to include the credentials in the Gemfile as part of the source URL. Credentials in the source URL will take precedence over credentials set using config. If your application requires a specific Ruby version or engine, specify your requirements using the ruby method, with the following arguments.

The version of Ruby that your application requires. If your application requires an alternate Ruby engine, such as JRuby, Rubinius or TruffleRuby, this should be the Ruby version that the engine is compatible with. Each application may specify a Ruby engine. If an engine is specified, an engine version must also be specified. For background: the reference or original implementation of the Ruby programming language is called Matz's Ruby Interpreter , or MRI for short.

This is named after Ruby creator Yukihiro Matsumoto, also known as Matz. MRI is the most widely used Ruby engine. Other implementations of Ruby exist.

Some of the more well-known implementations include Rubinius , and JRuby. Rubinius is an alternative implementation of Ruby written in Ruby. 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.

Specify gem requirements using the gem method, with the following arguments. Each gem MAY specify files that should be used when autorequiring via Bundler. You may pass an array with multiple files or true if the file you want required has the same name as gem or false to prevent any file from being autorequired. 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. The Bundler runtime allows its two main methods, Bundler.

The Bundler CLI allows you to specify a list of groups whose gems bundle install should not install with the without configuration. Also, calling Bundler. 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.

If a gem should only be used in a particular platform or set of platforms, you can specify them.