simple directory uploader

dir_upload_client.rb

require 'socket'
require 'json'

endpoint = ARGV[0]
src = ARGV[1]
dst = ARGV[2] || ''
unless endpoint =~ /\A.+:\d+\z/ && src
  puts "ARGV[0]: host:port"
  puts "ARGV[1]: src dir"
  puts "ARGV[2]: dst dir"
  exit
end
dst.gsub(/\A\/+|\/+\z/, '')

files = Dir.glob("#{src}/**/*")
host, port = endpoint.split(':')
socket = TCPSocket.new(host, port.to_i)
socket.puts JSON.dump({ type: 'stat', dir: dst })
server_files = JSON.parse socket.gets
server_file_sizes = server_files.map { |f| [f['path'], f['size']] }.to_h

files.each do |path|
  next unless File.file?(path)
  actual_size = File.size(path)
  server_size = server_file_sizes[path[src.size + 1..path.size]]
  if actual_size != server_size
    socket.puts JSON.dump({ type: 'upload', path: "#{dst}/#{path[src.size + 1..path.size]}", size: actual_size })
    socket.write File.read(path)
    puts "upload: #{path} (#{actual_size})"
    raise  unless socket.gets.chomp == '"ok"'
  end
end
socket.close

dir_upload_server.rb

require 'socket'
require 'json'
require 'fileutils'
port = ARGV[0]
unless /\A\d+\z/.match?(port)
  puts "ARGV[0]: port number"
  exit 1
end

FILE_DIR = File.absolute_path('files', __dir__)
Dir.mkdir(FILE_DIR) unless Dir.exist?(FILE_DIR)

def handle(socket)
  puts 'start'
  while (raw_req = socket.gets)
    req = JSON.parse raw_req.force_encoding('UTF-8')
    case req['type']
    when 'stat'
      dir = File.absolute_path(req['dir'], FILE_DIR)
      raise "invalid dir: #{dir}" unless dir.start_with?(FILE_DIR + '/') || dir == FILE_DIR
      files = []
      Dir.glob("#{dir}/**/*").each do |path|
        files << { path: path[dir.size + 1..], size: File.size(path) }
      end
      socket.puts JSON.dump(files)
    when 'upload'
      path = File.absolute_path(req['path'], FILE_DIR)
      raise "invalid path: #{path}" unless path.start_with?(FILE_DIR + '/')
      FileUtils.mkdir_p(File.dirname(path))
      bytesize = req['size']
      data = +''.b
      while data.bytesize < bytesize
        data << socket.readpartial([bytesize - data.bytesize, 65536].min)
      end
      File.write path, data
      puts "write: #{path} (#{bytesize})"
      socket.puts(JSON.dump('ok'))
    end
  end
rescue => e
  puts e
  puts e.backtrace
ensure
  puts 'close'
  socket.close
end

server = TCPServer.new(port.to_i)
p server.addr
loop do
  socket = server.accept
  Thread.new do
    handle(socket)
  end
end