services/keep/keep.rb

   1 #!/usr/bin/env ruby
   2
   3 require 'sinatra/base'
   4 require 'digest/md5'
   5 require 'digest/sha1'
   6
   7 class Keep < Sinatra::Base
   8   configure do
   9     mime_type :binary, 'application/octet-stream'
  10     enable :logging
  11     set :port, (ENV['PORT'] || '25107').to_i
  12     set :bind, (ENV['IP'] || '0.0.0.0')
  13   end
  14
  15   def verify_hash(data, hash)
  16     if hash.length == 32
  17       Digest::MD5.hexdigest(data) == hash && hash
  18     elsif hash.length == 40
  19       Digest::SHA1.hexdigest(data) == hash && hash
  20     else
  21       false
  22     end
  23   end
  24
  25   def self.debuglevel
  26     if ENV['DEBUG'] and ENV['DEBUG'].match /^-?\d+/
  27       ENV['DEBUG'].to_i
  28     else
  29       0
  30     end
  31   end
  32
  33   def self.debuglog(loglevel, msg)
  34     if debuglevel >= loglevel
  35       $stderr.puts "[keepd/#{$$} #{Time.now}] #{msg}"
  36     end
  37   end
  38   def debuglog(*args)
  39     self.class.debuglog *args
  40   end
  41
  42   def keepdirs
  43     @@keepdirs
  44   end
  45
  46   def self.keepdirs
  47     return @@keepdirs if defined? @@keepdirs
  48     # Configure backing store directories
  49     keepdirs = []
  50     rootdir = (ENV['KEEP_ROOT'] || '/').sub /\/$/, ''
  51     `mount`.split("\n").each do |mountline|
  52       dev, on_txt, mountpoint, type_txt, fstype, opts = mountline.split
  53       if on_txt == 'on' and type_txt == 'type'
  54         debuglog 2, "dir #{mountpoint} is mounted"
  55         if mountpoint[0..(rootdir.length)] == rootdir + '/'
  56           debuglog 2, "dir #{mountpoint} is in #{rootdir}/"
  57           keepdir = "#{mountpoint.sub /\/$/, ''}/keep"
  58           if File.exists? "#{keepdir}/."
  59             keepdirs << { :root => "#{keepdir}", :readonly => false }
  60             if opts.gsub(/[\(\)]/, '').split(',').index('ro')
  61               keepdirs[-1][:readonly] = true
  62             end
  63             debuglog 0, "keepdir #{keepdirs[-1].inspect}"
  64           end
  65         end
  66       end
  67     end
  68     @@keepdirs = keepdirs
  69   end
  70   self.keepdirs
  71
  72   def find_backfile(hash, opts)
  73     subdir = hash[0..2]
  74     keepdirs.each do |keepdir|
  75       backfile = "#{keepdir[:root]}/#{subdir}/#{hash}"
  76       if File.exists? backfile
  77         data = nil
  78         File.open("#{keepdir[:root]}/lock", "a+") do |f|
  79           if f.flock File::LOCK_EX
  80             data = File.read backfile
  81           end
  82         end
  83         if data and (!opts[:verify_hash] or verify_hash data, hash)
  84           return [backfile, data]
  85         end
  86       end
  87     end
  88     nil
  89   end
  90
  91   get '/:locator' do |locator|
  92     regs = locator.match /^([0-9a-f]{32,})/
  93     if regs
  94       hash = regs[1]
  95       backfile, data = find_backfile hash, :verify_hash => false
  96       if data
  97         content_type :binary
  98         body data
  99       else
 100         status 404
 101         body 'not found'
 102       end
 103     else
 104       pass
 105     end
 106   end
 107
 108   put '/:locator' do |locator|
 109     data = request.body.read
 110     hash = verify_hash(data, locator)
 111     if not hash
 112       status 422
 113       body "Checksum mismatch"
 114       return
 115     end
 116     backfile, havedata = find_backfile hash, :verify_hash => true
 117     if havedata
 118       status 200
 119       body 'OK'
 120     else
 121       wrote = nil
 122       subdir = hash[0..2]
 123       keepdirs.each do |keepdir|
 124         next if keepdir[:readonly]
 125         backdir = "#{keepdir[:root]}/#{subdir}"
 126         if !File.exists? backdir
 127           begin
 128             Dir.mkdir backdir
 129           rescue
 130           end
 131         end
 132         backfile = "#{keepdir[:root]}/#{subdir}/#{hash}"
 133         File.open("#{keepdir[:root]}/lock", "a+") do |lf|
 134           if lf.flock File::LOCK_EX
 135             File.open(backfile + ".tmp", "a+") do |wf|
 136               if wf.flock File::LOCK_EX
 137                 wf.seek 0, File::SEEK_SET
 138                 wf.truncate 0
 139                 wrote = wf.write data
 140               end
 141               if wrote == data.length
 142                 File.rename backfile+".tmp", backfile
 143                 break
 144               else
 145                 File.unlink backfile+".tmp"
 146               end
 147             end
 148           end
 149         end
 150       end
 151       if wrote == data.length
 152         status 200
 153         body 'OK'
 154       else
 155         status 500
 156         body 'Fail'
 157       end
 158     end
 159   end
 160
 161   if app_file == $0
 162     run! do |server|
 163       if ENV['SSL_CERT'] and ENV['SSL_KEY']
 164         ssl_options = {
 165           :cert_chain_file => ENV['SSL_CERT'],
 166           :private_key_file => ENV['SSL_KEY'],
 167           :verify_peer => false
 168         }
 169         server.ssl = true
 170         server.ssl_options = ssl_options
 171       end
 172     end
 173   end
 174 end