1 files changed, 164 insertions, 0 deletions
diff --git a/lib/rubygems/remote_fetcher.rb b/lib/rubygems/remote_fetcher.rb
new file mode 100644
index 0000000000..eac4ccaf01
--- /dev/null
+++ b/lib/rubygems/remote_fetcher.rb
@@ -0,0 +1,164 @@
+require 'net/http'
+require 'uri'
+
+require 'rubygems'
+require 'rubygems/gem_open_uri'
+
+##
+# RemoteFetcher handles the details of fetching gems and gem information from
+# a remote source.
+
+class Gem::RemoteFetcher
+
+  class FetchError < Gem::Exception; end
+
+  @fetcher = nil
+
+  # Cached RemoteFetcher instance.
+  def self.fetcher
+    @fetcher ||= new Gem.configuration[:http_proxy]
+  end
+
+  # Initialize a remote fetcher using the source URI and possible proxy
+  # information.
+  #
+  # +proxy+
+  # * [String]: explicit specification of proxy; overrides any environment
+  #             variable setting
+  # * nil: respect environment variables (HTTP_PROXY, HTTP_PROXY_USER,
+  #        HTTP_PROXY_PASS)
+  # * <tt>:no_proxy</tt>: ignore environment variables and _don't_ use a proxy
+  def initialize(proxy)
+    @proxy_uri =
+      case proxy
+      when :no_proxy then nil
+      when nil then get_proxy_from_env
+      when URI::HTTP then proxy
+      else URI.parse(proxy)
+      end
+  end
+
+  # Downloads +uri+.
+  def fetch_path(uri)
+    open_uri_or_path(uri) do |input|
+      input.read
+    end
+  rescue Timeout::Error
+    raise FetchError, "timed out fetching #{uri}"
+  rescue OpenURI::HTTPError, IOError, SocketError, SystemCallError => e
+    raise FetchError, "#{e.class}: #{e} reading #{uri}"
+  end
+
+  # Returns the size of +uri+ in bytes.
+  def fetch_size(uri)
+    return File.size(get_file_uri_path(uri)) if file_uri? uri
+
+    uri = URI.parse uri unless URI::Generic === uri
+
+    raise ArgumentError, 'uri is not an HTTP URI' unless URI::HTTP === uri
+
+    http = connect_to uri.host, uri.port
+
+    request = Net::HTTP::Head.new uri.request_uri
+
+    request.basic_auth unescape(uri.user), unescape(uri.password) unless
+      uri.user.nil? or uri.user.empty?
+
+    resp = http.request request
+
+    if resp.code !~ /^2/ then
+      raise Gem::RemoteSourceException,
+            "HTTP Response #{resp.code} fetching #{uri}"
+    end
+
+    if resp['content-length'] then
+      return resp['content-length'].to_i
+    else
+      resp = http.get uri.request_uri
+      return resp.body.size
+    end
+
+  rescue SocketError, SystemCallError, Timeout::Error => e
+    raise FetchError, "#{e.message} (#{e.class})"
+  end
+
+  private
+
+  def escape(str)
+    return unless str
+    URI.escape(str)
+  end
+
+  def unescape(str)
+    return unless str
+    URI.unescape(str)
+  end
+
+  # Returns an HTTP proxy URI if one is set in the environment variables.
+  def get_proxy_from_env
+    env_proxy = ENV['http_proxy'] || ENV['HTTP_PROXY']
+
+    return nil if env_proxy.nil? or env_proxy.empty?
+
+    uri = URI.parse env_proxy
+
+    if uri and uri.user.nil? and uri.password.nil? then
+      # Probably we have http_proxy_* variables?
+      uri.user = escape(ENV['http_proxy_user'] || ENV['HTTP_PROXY_USER'])
+      uri.password = escape(ENV['http_proxy_pass'] || ENV['HTTP_PROXY_PASS'])
+    end
+
+    uri
+  end
+
+  # Normalize the URI by adding "http://" if it is missing.
+  def normalize_uri(uri)
+    (uri =~ /^(https?|ftp|file):/) ? uri : "http://#{uri}"
+  end
+
+  # Connect to the source host/port, using a proxy if needed.
+  def connect_to(host, port)
+    if @proxy_uri
+      Net::HTTP::Proxy(@proxy_uri.host, @proxy_uri.port, unescape(@proxy_uri.user), unescape(@proxy_uri.password)).new(host, port)
+    else
+      Net::HTTP.new(host, port)
+    end
+  end
+
+  # Read the data from the (source based) URI, but if it is a file:// URI,
+  # read from the filesystem instead.
+  def open_uri_or_path(uri, &block)
+    if file_uri?(uri)
+      open(get_file_uri_path(uri), &block)
+    else
+      connection_options = {
+        "User-Agent" => "RubyGems/#{Gem::RubyGemsVersion} #{Gem::Platform.local}"
+      }
+
+      if @proxy_uri
+        http_proxy_url = "#{@proxy_uri.scheme}://#{@proxy_uri.host}:#{@proxy_uri.port}"  
+        connection_options[:proxy_http_basic_authentication] = [http_proxy_url, unescape(@proxy_uri.user)||'', unescape(@proxy_uri.password)||'']
+      end
+
+      uri = URI.parse uri unless URI::Generic === uri
+      unless uri.nil? || uri.user.nil? || uri.user.empty? then
+        connection_options[:http_basic_authentication] =
+          [unescape(uri.user), unescape(uri.password)]
+      end
+
+      open(uri, connection_options, &block)
+    end
+  end
+
+  # Checks if the provided string is a file:// URI.
+  def file_uri?(uri)
+    uri =~ %r{\Afile://}
+  end
+
+  # Given a file:// URI, returns its local path.
+  def get_file_uri_path(uri)
+    uri.sub(%r{\Afile://}, '')
+  end
+
+end
+