Extract the latest versions of each Ruby gem on your system

gems.rb

# frozen_string_literal: true

require "rubygems/package"
require "net/http"
require "tmpdir"

queue = Queue.new
Gem::SpecFetcher.new.available_specs(:latest).first.each do |source, gems|
  gems.each do |tuple|
    gem_name = File.basename(tuple.spec_name, ".gemspec")
    gem_url = source.uri.merge("/gems/#{gem_name}.gem")
    queue << [gem_name, gem_url]
  end
end

workers =
  16.times.map do
    Thread.new do
      Net::HTTP.start("rubygems.org", 443, use_ssl: true) do |http|
        until queue.empty?
          (gem_name, gem_url) = queue.shift

          http.request(Net::HTTP::Get.new(gem_url)) do |response|
            result =
              case response
              when Net::HTTPSuccess
                Dir.mktmpdir do |directory|
                  filepath = File.join(directory, "#{gem_name}.gem")
                  File.write(filepath, response.body)

                  begin
                    Gem::Package.new(filepath).extract_files(directory, "[!~]*")
                    ["OK", ""]
                  rescue ArgumentError => error
                    if error.message == "invalid byte sequence in UTF-8"
                      ["FAIL", "Gem incorrectly encoded"]
                    else
                      ["ERROR", "#{error.class.name}: #{error.message}"]
                    end
                  rescue RangeError => error
                    if error.message == "integer 100644 too big to convert to `unsigned short'"
                      ["FAIL", "Gem incorrectly packaged"]
                    else
                      ["ERROR", "#{error.class.name}: #{error.message}"]
                    end
                  rescue Errno::EACCES
                    ["FAIL", "Permission denied when creating files"]
                  rescue Errno::EEXIST
                    ["FAIL", "File exists in a path that a directory needs to be created"]
                  rescue Errno::EILSEQ
                    ["FAIL", "File path contains invalid byte sequence"]
                  rescue Gem::InvalidSpecificationException
                    ["FAIL", "The gemspec contains some kind of invalid values"]
                  rescue Gem::Package::FormatError
                    ["FAIL", "The gem is missing some files in the package"]
                  rescue Gem::Package::SymlinkError
                    ["FAIL", "Attempting to create a symlink outside the destination directory"]
                  rescue Psych::DisallowedClass
                    ["FAIL", "The gemspec YAML metadata contains a disallowed Ruby class"]
                  rescue Psych::SyntaxError
                    ["FAIL", "The gemspec YAML metadata contains a syntax error"]
                  rescue => error
                    ["ERROR", "#{error.class.name}: #{error.message}"]
                  end
                end
              else
                ["UNEXPECTED", response]
              end

            puts "%-70s %-12s %s" % [gem_name, *result]
          end
        end
      end
    end
  end

workers.each(&:join)