name : remote_fetcher.rb # frozen_string_literal: true require 'rubygems' require 'rubygems/request' require 'rubygems/request/connection_pools' require 'rubygems/s3_uri_signer' require 'rubygems/uri_formatter' require 'rubygems/uri_parsing' require 'rubygems/user_interaction' require 'resolv' require 'rubygems/deprecate' ## # RemoteFetcher handles the details of fetching gems and gem information from # a remote source. class Gem::RemoteFetcher include Gem::UserInteraction extend Gem::Deprecate include Gem::UriParsing ## # A FetchError exception wraps up the various possible IO and HTTP failures # that could happen while downloading from the internet. class FetchError < Gem::Exception include Gem::UriParsing ## # The URI which was being accessed when the exception happened. attr_accessor :uri def initialize(message, uri) super message uri = parse_uri(uri) uri.password = 'REDACTED' if uri.respond_to?(:password) && uri.password @uri = uri.to_s end def to_s # :nodoc: "#{super} (#{uri})" end end ## # A FetchError that indicates that the reason for not being # able to fetch data was that the host could not be contacted class UnknownHostError < FetchError end @fetcher = nil ## # Cached RemoteFetcher instance. def self.fetcher @fetcher ||= self.new Gem.configuration[:http_proxy] end attr_accessor :headers ## # 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 # # +headers+: A set of additional HTTP headers to be sent to the server when # fetching the gem. def initialize(proxy=nil, dns=nil, headers={}) require 'net/http' require 'stringio' require 'time' require 'uri' Socket.do_not_reverse_lookup = true @proxy = proxy @pools = {} @pool_lock = Mutex.new @cert_files = Gem::Request.get_cert_files @headers = headers end ## # Given a name and requirement, downloads this gem into cache and returns the # filename. Returns nil if the gem cannot be located. #-- # Should probably be integrated with #download below, but that will be a # larger, more encompassing effort. -erikh def download_to_cache(dependency) found, _ = Gem::SpecFetcher.fetcher.spec_for_dependency dependency return if found.empty? spec, source = found.max_by { |(s,_)| s.version } download spec, source.uri end ## # Moves the gem +spec+ from +source_uri+ to the cache dir unless it is # already there. If the source_uri is local the gem cache dir copy is # always replaced. def download(spec, source_uri, install_dir = Gem.dir) cache_dir = if Dir.pwd == install_dir # see fetch_command install_dir elsif File.writable? install_dir File.join install_dir, "cache" else File.join Gem.user_dir, "cache" end gem_file_name = File.basename spec.cache_file local_gem_path = File.join cache_dir, gem_file_name FileUtils.mkdir_p cache_dir rescue nil unless File.exist? cache_dir source_uri = parse_uri(source_uri) scheme = source_uri.scheme # URI.parse gets confused by MS Windows paths with forward slashes. scheme = nil if scheme =~ /^[a-z]$/i # REFACTOR: split this up and dispatch on scheme (eg download_http) # REFACTOR: be sure to clean up fake fetcher when you do this... cleaner case scheme when 'http', 'https', 's3' then unless File.exist? local_gem_path begin verbose "Downloading gem #{gem_file_name}" remote_gem_path = source_uri + "gems/#{gem_file_name}" self.cache_update_path remote_gem_path, local_gem_path rescue FetchError raise if spec.original_platform == spec.platform alternate_name = "#{spec.original_name}.gem" verbose "Failed, downloading gem #{alternate_name}" remote_gem_path = source_uri + "gems/#{alternate_name}" self.cache_update_path remote_gem_path, local_gem_path end end when 'file' then begin path = source_uri.path path = File.dirname(path) if File.extname(path) == '.gem' remote_gem_path = Gem::Util.correct_for_windows_path(File.join(path, 'gems', gem_file_name)) FileUtils.cp(remote_gem_path, local_gem_path) rescue Errno::EACCES local_gem_path = source_uri.to_s end verbose "Using local gem #{local_gem_path}" when nil then # TODO test for local overriding cache source_path = if Gem.win_platform? && source_uri.scheme && !source_uri.path.include?(':') "#{source_uri.scheme}:#{source_uri.path}" else source_uri.path end source_path = Gem::UriFormatter.new(source_path).unescape begin FileUtils.cp source_path, local_gem_path unless File.identical?(source_path, local_gem_path) rescue Errno::EACCES local_gem_path = source_uri.to_s end verbose "Using local gem #{local_gem_path}" else raise ArgumentError, "unsupported URI scheme #{source_uri.scheme}" end local_gem_path end ## # File Fetcher. Dispatched by +fetch_path+. Use it instead. def fetch_file(uri, *_) Gem.read_binary Gem::Util.correct_for_windows_path uri.path end ## # HTTP Fetcher. Dispatched by +fetch_path+. Use it instead. def fetch_http(uri, last_modified = nil, head = false, depth = 0) fetch_type = head ? Net::HTTP::Head : Net::HTTP::Get response = request uri, fetch_type, last_modified do |req| headers.each { |k,v| req.add_field(k,v) } end case response when Net::HTTPOK, Net::HTTPNotModified then response.uri = uri if response.respond_to? :uri head ? response : response.body when Net::HTTPMovedPermanently, Net::HTTPFound, Net::HTTPSeeOther, Net::HTTPTemporaryRedirect then raise FetchError.new('too many redirects', uri) if depth > 10 unless location = response['Location'] raise FetchError.new("redirecting but no redirect location was given", uri) end location = parse_uri location if https?(uri) && !https?(location) raise FetchError.new("redirecting to non-https resource: #{location}", uri) end fetch_http(location, last_modified, head, depth + 1) else raise FetchError.new("bad response #{response.message} #{response.code}", uri) end end alias :fetch_https :fetch_http ## # Downloads +uri+ and returns it as a String. def fetch_path(uri, mtime = nil, head = false) uri = parse_uri uri unless uri.scheme raise ArgumentError, "uri scheme is invalid: #{uri.scheme.inspect}" end data = send "fetch_#{uri.scheme}", uri, mtime, head if data and !head and uri.to_s =~ /\.gz$/ begin data = Gem::Util.gunzip data rescue Zlib::GzipFile::Error raise FetchError.new("server did not return a valid file", uri) end end data rescue Timeout::Error raise UnknownHostError.new('timed out', uri) rescue IOError, SocketError, SystemCallError, *(OpenSSL::SSL::SSLError if defined?(OpenSSL)) => e if e.message =~ /getaddrinfo/ raise UnknownHostError.new('no such name', uri) else raise FetchError.new("#{e.class}: #{e}", uri) end end def fetch_s3(uri, mtime = nil, head = false) begin public_uri = s3_uri_signer(uri).sign rescue Gem::S3URISigner::ConfigurationError, Gem::S3URISigner::InstanceProfileError => e raise FetchError.new(e.message, "s3://#{uri.host}") end fetch_https public_uri, mtime, head end # we have our own signing code here to avoid a dependency on the aws-sdk gem def s3_uri_signer(uri) Gem::S3URISigner.new(uri) end ## # Downloads +uri+ to +path+ if necessary. If no path is given, it just # passes the data. def cache_update_path(uri, path = nil, update = true) mtime = path && File.stat(path).mtime rescue nil data = fetch_path(uri, mtime) if data == nil # indicates the server returned 304 Not Modified return Gem.read_binary(path) end if update and path Gem.write_binary(path, data) end data end ## # Returns the size of +uri+ in bytes. def fetch_size(uri) response = fetch_path(uri, nil, true) response['content-length'].to_i end deprecate :fetch_size, :none, 2019, 12 ## # Performs a Net::HTTP request of type +request_class+ on +uri+ returning # a Net::HTTP response object. request maintains a table of persistent # connections to reduce connect overhead. def request(uri, request_class, last_modified = nil) proxy = proxy_for @proxy, uri pool = pools_for(proxy).pool_for uri request = Gem::Request.new uri, request_class, last_modified, pool request.fetch do |req| yield req if block_given? end end def https?(uri) uri.scheme.downcase == 'https' end def close_all @pools.each_value {|pool| pool.close_all} end private def proxy_for(proxy, uri) Gem::Request.proxy_uri(proxy || Gem::Request.get_proxy_from_env(uri.scheme)) end def pools_for(proxy) @pool_lock.synchronize do @pools[proxy] ||= Gem::Request::ConnectionPools.new proxy, @cert_files end end end