multipart_upload.rb

#!/usr/bin/env ruby

require 'net/http'
require 'uri'

BLOCK_SIZE = 1048576 # bytes
URL = "http://localhost:8000/upload"

filename = ARGV[0]
f = File.open(filename, 'rb')
file_size = f.stat.size
session_id = (1..20).map { rand 10 }.join

last_block = file_size % BLOCK_SIZE
block_count = (file_size / BLOCK_SIZE)
block_count += 1 unless last_block.zero?

puts "Uploading \"#{filename}\" as #{block_count} pieces of #{(file_size.to_f/block_count).ceil} bytes each"

block_count.times do |i|
  body = f.read(BLOCK_SIZE)
  block_start = BLOCK_SIZE * i

  block_end = block_start + BLOCK_SIZE - 1
  block_end = file_size if block_end > file_size

  headers = {'Content-Type'         => 'application/octet-stream',
             'Content-Disposition'  => "attachment; filename=\"#{File.basename(filename)}\"",
             'X-Content-Range'      => "bytes #{block_start}-#{block_end}/#{file_size}",
             'X-Session-ID'         => session_id}

  puts "Uploading chunk #{i+1}: #{headers['X-Content-Range']}"

  uri = URI.parse(URL)
  http = Net::HTTP.new(uri.host, uri.port)
  response = http.post(uri.path, body, headers)
end