The command manager registers and installs all the individual sub-commands supported by the gem command.
Extra commands can be provided by writing a rubygems_plugin.rb file in an installed gem. You should register your command against the Gem::CommandManager
instance, like this:
# file rubygems_plugin.rb require 'rubygems/command_manager' Gem::CommandManager.instance.register_command :edit
You should put the implementation of your command in rubygems/commands.
# file rubygems/commands/edit_command.rb class Gem::Commands::EditCommand < Gem::Command # ... end
See Gem::Command
for instructions on writing gem commands.
Raised when attempting to uninstall a gem that isn’t in GEM_HOME.
Potentially raised when a specification is validated.
Used to raise parsing and loading errors
Potentially raised when a specification is validated.
Raised when a gem dependencies file specifies a ruby version that does not match the current version.
Raised by Gem::Validator
when something is not right in a gem.
Raised to indicate that a system exit should occur with the specified exit_code
Raised by Resolver when a dependency requests a gem for which there is no spec.
Example using a Gem::Package
Builds a .gem file given a Gem::Specification
. A .gem file is a tarball which contains a data.tar.gz, metadata.gz, checksums.yaml.gz and possibly signatures.
require 'rubygems' require 'rubygems/package' spec = Gem::Specification.new do |s| s.summary = "Ruby based make-like utility." s.name = 'rake' s.version = PKG_VERSION s.requirements << 'none' s.files = PKG_FILES s.description = <<-EOF Rake is a Make-like program implemented in Ruby. Tasks and dependencies are specified in standard Ruby syntax. EOF end Gem::Package.build spec
Reads a .gem file.
require 'rubygems' require 'rubygems/package' the_gem = Gem::Package.new(path_to_dot_gem) the_gem.contents # get the files in the gem the_gem.extract_files destination_directory # extract the gem into a directory the_gem.spec # get the spec out of the gem the_gem.verify # check the gem is OK (contains valid gem specification, contains a not corrupt contents archive)
files
are the files in the .gem tar file, not the Ruby files in the gem extract_files
and contents
automatically call verify
Create a package based upon a Gem::Specification
. Gem packages, as well as zip files and tar/gzipped packages can be produced by this task.
In addition to the Rake targets generated by Rake::PackageTask, a Gem::PackageTask
will also generate the following tasks:
Create a RubyGems package with the given name and version.
Example using a Gem::Specification
:
require 'rubygems' require 'rubygems/package_task' spec = Gem::Specification.new do |s| s.summary = "Ruby based make-like utility." s.name = 'rake' s.version = PKG_VERSION s.requirements << 'none' s.files = PKG_FILES s.description = <<-EOF Rake is a Make-like program implemented in Ruby. Tasks and dependencies are specified in standard Ruby syntax. EOF end Gem::PackageTask.new(spec) do |pkg| pkg.need_zip = true pkg.need_tar = true end
A Requirement
is a set of one or more version restrictions. It supports a few (=, !=, >, <, >=, <=, ~>
) different restriction operators.
See Gem::Version
for a description on how versions and requirements work together in RubyGems.
The Specification
class contains the information for a gem. Typically defined in a .gemspec file or a Rakefile, and looks like this:
Gem::Specification.new do |s| s.name = 'example' s.version = '0.1.0' s.licenses = ['MIT'] s.summary = "This is an example!" s.description = "Much longer explanation of the example!" s.authors = ["Ruby Coder"] s.email = 'rubycoder@example.com' s.files = ["lib/example.rb"] s.homepage = 'https://rubygems.org/gems/example' s.metadata = { "source_code_uri" => "https://github.com/example/example" } end
Starting in RubyGems 2.0, a Specification
can hold arbitrary metadata. See metadata
for restrictions on the format and size of metadata items you may add to a specification.
Gem::StubSpecification
reads the stub: line from the gemspec. This prevents us having to eval the entire gemspec in order to find out certain information.
The UriFormatter
handles URIs from user-input and escaping.
uf = Gem::UriFormatter.new 'example.com' p uf.normalize #=> 'http://example.com'
Gem::StreamUI
implements a simple stream based user interface.
Validator
performs various gem file and gem database validation
This class is responsible for taking a code block that exists at a far indentaion and then iteratively increasing the block so that it captures everything within the same indentation block.
def dog puts "bow" puts "wow" end
block = BlockExpand.new
(code_lines: code_lines)
.call(CodeBlock.new(lines: code_lines[1]))
puts block.to_s # => puts “bow”
puts "wow"
Once a code block has captured everything at a given indentation level then it will expand to capture surrounding indentation.
block = BlockExpand.new
(code_lines: code_lines)
.call(block)
block.to_s # => def dog
puts "bow" puts "wow" end