twisted/names/test/test_tap.py

   1 # Copyright (c) Twisted Matrix Laboratories.
   2 # See LICENSE for details.
   3
   4 """
   5 Tests for L{twisted.names.tap}.
   6 """
   7
   8 from twisted.trial.unittest import TestCase
   9 from twisted.python.usage import UsageError
  10 from twisted.names.tap import Options, _buildResolvers
  11 from twisted.names.dns import PORT
  12 from twisted.names.secondary import SecondaryAuthorityService
  13 from twisted.names.resolve import ResolverChain
  14 from twisted.names.client import Resolver
  15
  16 class OptionsTests(TestCase):
  17     """
  18     Tests for L{Options}, defining how command line arguments for the DNS server
  19     are parsed.
  20     """
  21     def test_malformedSecondary(self):
  22         """
  23         If the value supplied for an I{--secondary} option does not provide a
  24         server IP address, optional port number, and domain name,
  25         L{Options.parseOptions} raises L{UsageError}.
  26         """
  27         options = Options()
  28         self.assertRaises(
  29             UsageError, options.parseOptions, ['--secondary', ''])
  30         self.assertRaises(
  31             UsageError, options.parseOptions, ['--secondary', '1.2.3.4'])
  32         self.assertRaises(
  33             UsageError, options.parseOptions, ['--secondary', '1.2.3.4:hello'])
  34         self.assertRaises(
  35             UsageError, options.parseOptions,
  36             ['--secondary', '1.2.3.4:hello/example.com'])
  37
  38
  39     def test_secondary(self):
  40         """
  41         An argument of the form C{"ip/domain"} is parsed by L{Options} for the
  42         I{--secondary} option and added to its list of secondaries, using the
  43         default DNS port number.
  44         """
  45         options = Options()
  46         options.parseOptions(['--secondary', '1.2.3.4/example.com'])
  47         self.assertEqual(
  48             [(('1.2.3.4', PORT), ['example.com'])], options.secondaries)
  49
  50
  51     def test_secondaryExplicitPort(self):
  52         """
  53         An argument of the form C{"ip:port/domain"} can be used to specify an
  54         alternate port number for for which to act as a secondary.
  55         """
  56         options = Options()
  57         options.parseOptions(['--secondary', '1.2.3.4:5353/example.com'])
  58         self.assertEqual(
  59             [(('1.2.3.4', 5353), ['example.com'])], options.secondaries)
  60
  61
  62     def test_secondaryAuthorityServices(self):
  63         """
  64         After parsing I{--secondary} options, L{Options} constructs a
  65         L{SecondaryAuthorityService} instance for each configured secondary.
  66         """
  67         options = Options()
  68         options.parseOptions(['--secondary', '1.2.3.4:5353/example.com',
  69                               '--secondary', '1.2.3.5:5354/example.com'])
  70         self.assertEqual(len(options.svcs), 2)
  71         secondary = options.svcs[0]
  72         self.assertIsInstance(options.svcs[0], SecondaryAuthorityService)
  73         self.assertEqual(secondary.primary, '1.2.3.4')
  74         self.assertEqual(secondary._port, 5353)
  75         secondary = options.svcs[1]
  76         self.assertIsInstance(options.svcs[1], SecondaryAuthorityService)
  77         self.assertEqual(secondary.primary, '1.2.3.5')
  78         self.assertEqual(secondary._port, 5354)
  79
  80
  81     def test_recursiveConfiguration(self):
  82         """
  83         Recursive DNS lookups, if enabled, should be a last-resort option.
  84         Any other lookup method (cache, local lookup, etc.) should take
  85         precedence over recursive lookups
  86         """
  87         options = Options()
  88         options.parseOptions(['--hosts-file', 'hosts.txt', '--recursive'])
  89         ca, cl = _buildResolvers(options)
  90
  91         # Extra cleanup, necessary on POSIX because client.Resolver doesn't know
  92         # when to stop parsing resolv.conf.  See #NNN for improving this.
  93         for x in cl:
  94             if isinstance(x, ResolverChain):
  95                 recurser = x.resolvers[-1]
  96                 if isinstance(recurser, Resolver):
  97                     recurser._parseCall.cancel()
  98
  99         self.assertIsInstance(cl[-1], ResolverChain)