require 'open-uri' class Downloader class GNU < self def self.download(name, *rest) super("http://git.savannah.gnu.org/gitweb/?p=config.git;a=blob_plain;f=#{name};hb=HEAD", name, *rest) end end class RubyGems < self def self.download(name, *rest) super("https://rubygems.org/downloads/#{name}", name, *rest) end end Gems = RubyGems class Unicode < self def self.download(name, *rest) super("http://www.unicode.org/Public/UCD/latest/ucd/#{name}", name, *rest) end end def self.mode_for(data) /\A#!/ =~ data ? 0755 : 0644 end def self.http_options(file, since) options = {} if since case since when true since = (File.mtime(file).httpdate rescue nil) when Time since = since.httpdate end if since options['If-Modified-Since'] = since end end options end # Downloader.download(url, name, [dir, [ims]]) # # Update a file from url if newer version is available. # Creates the file if the file doesn't yet exist; however, the # directory where the file is being created has to exist already. # If +ims+ is false, always download url regardless of its last # modified time. # # Example usage: # download 'http://www.unicode.org/Public/UCD/latest/ucd/UnicodeData.txt', # 'UnicodeData.txt', 'enc/unicode/data' def self.download(url, name, dir = nil, ims = true) file = dir ? File.join(dir, name) : name return true if ims.nil? and File.exist?(file) url = URI(url) if $VERBOSE $stdout.print "downloading #{name} ... " $stdout.flush end begin data = url.read(http_options(file, ims)) rescue OpenURI::HTTPError => http_error if http_error.message =~ /^304 / # 304 Not Modified if $VERBOSE $stdout.puts "not modified" $stdout.flush end return true end raise end mtime = nil open(file, "wb", 0600) do |f| f.write(data) f.chmod(mode_for(data)) mtime = data.meta["last-modified"] end if mtime mtime = Time.httpdate(mtime) File.utime(mtime, mtime, file) end if $VERBOSE $stdout.puts "done" $stdout.flush end true rescue => e raise e.class, "failed to download #{name}\n#{e.message}: #{url}", e.backtrace end end if $0 == __FILE__ ims = true until ARGV.empty? case ARGV[0] when '-d' destdir = ARGV[1] ARGV.shift when '-e' ims = nil when /\A-/ abort "#{$0}: unknown option #{ARGV[0]}" else break end ARGV.shift end dl = Downloader.constants.find do |name| ARGV[0].casecmp(name.to_s) == 0 end $VERBOSE = true if dl dl = Downloader.const_get(dl) ARGV.shift ARGV.each do |name| dl.download(name, destdir, ims) end else abort "usage: #{$0} url name" unless ARGV.size == 2 Downloader.download(ARGV[0], ARGV[1], destdir, ims) end end