class Gem::Source

A Source knows how to list and fetch gems from a RubyGems marshal index.

There are other Source subclasses for installed gems, local gems, the bundler dependency API and so-forth.

Attributes

uri [R]

The URI this source will fetch gems from.

Public Class Methods

new (uri)

Creates a new Source which will use the index located at uri.

# File lib/rubygems/source.rb, line 28
def initialize(uri)
  require_relative "uri"
  @uri = Gem::Uri.parse!(uri)
  @update_cache = nil
end

Public Instance Methods

<=> (other)

Sources are ordered by installation preference.

# File lib/rubygems/source.rb, line 37
def <=>(other)
  case other
  when Gem::Source::Installed,
       Gem::Source::Local,
       Gem::Source::Lock,
       Gem::Source::SpecificFile,
       Gem::Source::Git,
       Gem::Source::Vendor then
    -1
  when Gem::Source then
    unless @uri
      return 0 unless other.uri
      return 1
    end

    return -1 unless other.uri

    # Returning 1 here ensures that when sorting a list of sources, the
    # original ordering of sources supplied by the user is preserved.
    return 1 unless @uri.to_s == other.uri.to_s

    0
  end
end

cache_dir (uri)

Returns the local directory to write uri to.

# File lib/rubygems/source.rb, line 101
def cache_dir(uri)
  # Correct for windows paths
  escaped_path = uri.path.sub(%r{^/([a-z]):/}i, '/\\1-/')

  File.join Gem.spec_cache_dir, "#{uri.host}%#{uri.port}", File.dirname(escaped_path)
end

download (spec, dir=Dir.pwd)

Downloads spec and writes it to dir. See also Gem::RemoteFetcher#download.

# File lib/rubygems/source.rb, line 210
def download(spec, dir=Dir.pwd)
  fetcher = Gem::RemoteFetcher.fetcher
  fetcher.download spec, uri.to_s, dir
end

fetch_spec (name_tuple)

Fetches a specification for the given name_tuple.

# File lib/rubygems/source.rb, line 124
def fetch_spec(name_tuple)
  fetcher = Gem::RemoteFetcher.fetcher

  spec_file_name = name_tuple.spec_name

  source_uri = enforce_trailing_slash(uri) + "#{Gem::MARSHAL_SPEC_DIR}#{spec_file_name}"

  cache_dir = cache_dir source_uri

  local_spec = File.join cache_dir, spec_file_name

  if File.exist? local_spec
    spec = Gem.read_binary local_spec
    Gem.load_safe_marshal
    spec = begin
             Gem::SafeMarshal.safe_load(spec)
           rescue StandardError
             nil
           end
    return spec if spec
  end

  source_uri.path << ".rz"

  spec = fetcher.fetch_path source_uri
  spec = Gem::Util.inflate spec

  if update_cache?
    require "fileutils"
    FileUtils.mkdir_p cache_dir

    File.open local_spec, "wb" do |io|
      io.write spec
    end
  end

  Gem.load_safe_marshal
  # TODO: Investigate setting Gem::Specification#loaded_from to a URI
  Gem::SafeMarshal.safe_load spec
end

load_specs (type)

Loads type kind of specs fetching from +@uri+ if the on-disk cache is out of date.

type is one of the following:

:released => Return the list of all released specs :latest => Return the list of only the highest version of each gem :prerelease => Return the list of all prerelease only specs

# File lib/rubygems/source.rb, line 176
def load_specs(type)
  file       = FILES[type]
  fetcher    = Gem::RemoteFetcher.fetcher
  file_name  = "#{file}.#{Gem.marshal_version}"
  spec_path  = enforce_trailing_slash(uri) + "#{file_name}.gz"
  cache_dir  = cache_dir spec_path
  local_file = File.join(cache_dir, file_name)
  retried    = false

  if update_cache?
    require "fileutils"
    FileUtils.mkdir_p cache_dir
  end

  spec_dump = fetcher.cache_update_path spec_path, local_file, update_cache?

  Gem.load_safe_marshal
  begin
    Gem::NameTuple.from_list Gem::SafeMarshal.safe_load(spec_dump)
  rescue ArgumentError
    if update_cache? && !retried
      FileUtils.rm local_file
      retried = true
      retry
    else
      raise Gem::Exception.new("Invalid spec cache file in #{local_file}")
    end
  end
end

typo_squatting? (host, distance_threshold=4)

# File lib/rubygems/source.rb, line 230
def typo_squatting?(host, distance_threshold=4)
  return if @uri.host.nil?
  levenshtein_distance(@uri.host, host).between? 1, distance_threshold
end

update_cache? ()

Returns true when it is possible and safe to update the cache directory.

# File lib/rubygems/source.rb, line 111
def update_cache?
  return @update_cache unless @update_cache.nil?
  @update_cache =
    begin
      File.stat(Gem.user_home).uid == Process.uid
    rescue Errno::ENOENT
      false
    end
end