dcav-http-upload-server/server.rb

require 'sinatra'

set :bind, '127.0.0.1'
set :port, '35257'

USERS = { 'christoffermadsen' => 'lolol' }
FILENAME_GENERATOR = lambda {rand(36**6).to_s(36)}

get '/' do
  split_log = Array.new
  File.open 'uploads.log', 'r' do |log|
    log.each_line { |l| split_log << l }
  end
  
  count = split_log.count
  latest = split_log[-1]
  
  body "<b>#{count}</b> image#{unless count == 1 then "s" end} uploaded<br>" +
       "Latest uploaded: <b>#{latest}</b>"
end

post '/upload' do
  user = params['user']
  pass = params['pass']
  device_id = params['device_id']

  puts "Receiving data from user #{user} on device #{device_id}"
  puts "Authenticating with passphrase \"#{pass}\" on device #{device_id}"

  unless pass == USERS[user]
    return 401
  end

  puts "Authentication successful for user #{user} on device #{device_id}"

  # Prefer filename sent with the request
  impure_filename = (request['filename'] || FILENAME_GENERATOR.call) << ".png"
  filename = sanitize_filename(impure_filename)
  
  puts ENV['HOME']
  File.open "#{ENV['HOME']}/public_html/screenshots/#{filename}", 'w+' do |f|
    f << request['imagedata'][:tempfile].read
  end

  File.open "uploads.log", 'a+' do |log|
    log << filename + "\n"
  end
  
  return [200, filename]
end

def sanitize_filename(filename)
  # https://stackoverflow.com/questions/1939333/how-to-make-a-ruby-string-safe-for-a-filesystem#
  fn = filename.split /(?<=.)\.(?=[^.])(?!.*\.[^.])/m
  fn.map! { |s| s.gsub /[^a-z0-9\-]+/i, '_' }
  return fn.join '.'
end