bin/mailshears

   1 #!/usr/bin/ruby -wU
   2 #
   3 # mailshears, to mangle your mail garden
   4 #
   5
   6 # Load all of our lib/ code.
   7 require 'mailshears'
   8
   9 # Define a usage string using the program name.
  10 program_name = File.basename($PROGRAM_NAME)
  11
  12 # Defaults
  13 mode_name = 'prune'
  14 mode = :prune
  15
  16 # Before doing anything else, check for "-h" and "--help" in the args,
  17 # because those should cause us to dump usage info and bail out.
  18 if ARGV.include?('-h') or ARGV.include?('--help') then
  19   puts "Usage: #{UserInterface.usage(program_name)}"
  20   Kernel.exit(ExitCodes::SUCCESS)
  21 end
  22
  23
  24 # If a mode was supplied, it should be in ARGV[0].
  25 if ARGV.length() > 0
  26   mode_names = ['prune', 'rm', 'mv']
  27   if mode_names.include?(ARGV.first().downcase()) then
  28     # Peel the mode name off the head of the list.
  29     mode_name = ARGV.shift()
  30   end
  31 end
  32
  33 # Determine the mode from its name.
  34 if mode_name == 'rm' then
  35   mode = :rm
  36 elsif mode_name == 'mv' then
  37   mode = :mv
  38 end
  39
  40 # Since we removed the mode name (if it existed) from ARGV, what
  41 # remains should be the required arguments. Figure out if we have the
  42 # wrong number of arguments, and store the associated error message in
  43 # args_error_message if necessary.
  44 args_error_message = nil
  45
  46 if mode == :prune and ARGV.length() != 0 then
  47   args_error_message = "ERROR: prune mode takes no additional arguments."
  48 elsif mode == :rm and ARGV.length() < 1 then
  49   args_error_message = "ERROR: rm mode takes two or more user arguments."
  50 elsif mode == :mv and ARGV.length() != 2 then
  51   args_error_message = "ERROR: mv mode takes exactly two user arguments."
  52 end
  53
  54 # If we got the wrong number of arguments, we'll have an error message
  55 # here. Report it and exit with a failure code.
  56 if not args_error_message.nil? then
  57   STDERR.puts args_error_message
  58   puts "Usage: #{UserInterface.usage(program_name)}"
  59   Kernel.exit(ExitCodes::BAD_COMMAND_LINE)
  60 end
  61
  62
  63 # Load each of the plugins that we'll need.
  64 cfg = Configuration.new()
  65
  66 cfg.plugins.each do |plugin_file|
  67   require "#{mode_name}/plugins/#{plugin_file}"
  68 end
  69
  70 # And the runners.
  71 require "#{mode_name}/#{mode_name}_runner"
  72 require "#{mode_name}/#{mode_name}_dummy_runner"
  73
  74 # Now we figure out which plugin module to use based on our mode.
  75 plugin_module = nil
  76
  77 if mode == :rm then
  78   plugin_module = RmPlugin
  79 elsif mode == :mv then
  80   plugin_module = MvPlugin
  81 else
  82   # Safe, catch-all default
  83   plugin_module = PrunePlugin
  84 end
  85
  86 # Parse the remaining arguments as User/Domain objects. If we get some
  87 # other argument that isn't one of those, it's an error.
  88 parsed_args = []
  89
  90 ARGV.each do |arg|
  91   begin
  92     u = User.new(arg)
  93     parsed_args << u
  94   rescue InvalidUserError
  95     begin
  96       d = Domain.new(arg)
  97       parsed_args << d
  98     rescue InvalidDomainError
  99       STDERR.puts "ERROR: invalid user/domain argument #{arg}"
 100       Kernel.exit(ExitCodes::BAD_COMMAND_LINE)
 101     end
 102   end
 103 end
 104
 105
 106 # Buffer the output so that we can avoid printing the informational
 107 # header when no plugins produce output.
 108 require 'stringio'
 109 output_buffer = StringIO.new()
 110 $stdout = output_buffer
 111
 112 begin
 113   plugin_module.run(cfg, *parsed_args)
 114 ensure
 115   # Now restore stdout, and print the header plus whatever the plugins
 116   # produced (if they produced anything). If they didn't produce any
 117   # output, then we avoid printing the header.
 118   #
 119   # This gets wrapped in an "ensure" block because otherwise, if
 120   # plugin_module.run() crashes, the traceback will get stored in
 121   # output_buffer and never get printed.
 122   $stdout = STDOUT
 123
 124   if output_buffer.size > 0 then
 125     puts UserInterface.make_header(program_name, plugin_module.to_s())
 126     puts output_buffer.string()
 127   end
 128 end
 129
 130 # If we made it here without crashing, well that sounds pretty
 131 # successful to me.
 132 Kernel.exit(ExitCodes::SUCCESS)