apt_dht_Khashmir/DHT.py

   1
   2 import os, sha, random
   3
   4 from twisted.internet import defer, reactor
   5 from twisted.internet.abstract import isIPAddress
   6 from twisted.trial import unittest
   7 from zope.interface import implements
   8
   9 from apt_dht.interfaces import IDHT
  10 from khashmir import Khashmir
  11
  12 class DHTError(Exception):
  13     """Represents errors that occur in the DHT."""
  14
  15 class DHT:
  16
  17     implements(IDHT)
  18
  19     def __init__(self):
  20         self.config = None
  21         self.cache_dir = ''
  22         self.bootstrap = []
  23         self.bootstrap_node = False
  24         self.joining = None
  25         self.joined = False
  26         self.storing = {}
  27         self.retrieving = {}
  28         self.retrieved = {}
  29
  30     def loadConfig(self, config, section):
  31         """See L{apt_dht.interfaces.IDHT}."""
  32         self.config_parser = config
  33         self.section = section
  34         self.config = {}
  35         self.cache_dir = self.config_parser.get(section, 'cache_dir')
  36         self.bootstrap = self.config_parser.getstringlist(section, 'BOOTSTRAP')
  37         self.bootstrap_node = self.config_parser.getboolean(section, 'BOOTSTRAP_NODE')
  38         for k in self.config_parser.options(section):
  39             if k in ['K', 'HASH_LENGTH', 'CONCURRENT_REQS', 'STORE_REDUNDANCY',
  40                      'MAX_FAILURES', 'PORT']:
  41                 self.config[k] = self.config_parser.getint(section, k)
  42             elif k in ['CHECKPOINT_INTERVAL', 'MIN_PING_INTERVAL',
  43                        'BUCKET_STALENESS', 'KEINITIAL_DELAY', 'KE_DELAY', 'KE_AGE']:
  44                 self.config[k] = self.config_parser.gettime(section, k)
  45             else:
  46                 self.config[k] = self.config_parser.get(section, k)
  47
  48     def join(self):
  49         """See L{apt_dht.interfaces.IDHT}."""
  50         if self.config is None:
  51             raise DHTError, "configuration not loaded"
  52         if self.joining:
  53             raise DHTError, "a join is already in progress"
  54
  55         self.khashmir = Khashmir(self.config, self.cache_dir)
  56
  57         self.joining = defer.Deferred()
  58         for node in self.bootstrap:
  59             host, port = node.rsplit(':', 1)
  60             port = int(port)
  61             if isIPAddress(host):
  62                 self._join_gotIP(host, port)
  63             else:
  64                 reactor.resolve(host).addCallback(self._join_gotIP, port)
  65
  66         return self.joining
  67
  68     def _join_gotIP(self, ip, port):
  69         """Called after an IP address has been found for a single bootstrap node."""
  70         self.khashmir.addContact(ip, port, self._join_single)
  71
  72     def _join_single(self):
  73         """Called when a single bootstrap node has been added."""
  74         self.khashmir.findCloseNodes(self._join_complete)
  75
  76     def _join_complete(self, result):
  77         """Called when the tables have been initialized with nodes."""
  78         if not self.joined:
  79             self.joined = True
  80             if len(result) > 0 or self.bootstrap_node:
  81                 df = self.joining
  82                 self.joining = None
  83                 df.callback(result)
  84             else:
  85                 df = self.joining
  86                 self.joining = None
  87                 df.errback(DHTError('could not find any nodes to bootstrap to'))
  88
  89     def leave(self):
  90         """See L{apt_dht.interfaces.IDHT}."""
  91         if self.config is None:
  92             raise DHTError, "configuration not loaded"
  93
  94         if self.joined or self.joining:
  95             if self.joining:
  96                 self.joining.errback(DHTError('still joining when leave was called'))
  97                 self.joining = None
  98             self.joined = False
  99             self.khashmir.shutdown()
 100
 101     def getValue(self, key):
 102         """See L{apt_dht.interfaces.IDHT}."""
 103         if self.config is None:
 104             raise DHTError, "configuration not loaded"
 105         if not self.joined:
 106             raise DHTError, "have not joined a network yet"
 107
 108         d = defer.Deferred()
 109         if key not in self.retrieving:
 110             self.khashmir.valueForKey(key, self._getValue)
 111         self.retrieving.setdefault(key, []).append(d)
 112         return d
 113
 114     def _getValue(self, key, result):
 115         if result:
 116             self.retrieved.setdefault(key, []).extend(result)
 117         else:
 118             final_result = []
 119             if key in self.retrieved:
 120                 final_result = self.retrieved[key]
 121                 del self.retrieved[key]
 122             for i in range(len(self.retrieving[key])):
 123                 d = self.retrieving[key].pop(0)
 124                 d.callback(final_result)
 125             del self.retrieving[key]
 126
 127     def storeValue(self, key, value):
 128         """See L{apt_dht.interfaces.IDHT}."""
 129         if self.config is None:
 130             raise DHTError, "configuration not loaded"
 131         if not self.joined:
 132             raise DHTError, "have not joined a network yet"
 133
 134         if key in self.storing and value in self.storing[key]:
 135             raise DHTError, "already storing that key with the same value"
 136
 137         d = defer.Deferred()
 138         self.khashmir.storeValueForKey(key, value, self._storeValue)
 139         self.storing.setdefault(key, {})[value] = d
 140         return d
 141
 142     def _storeValue(self, key, value, result):
 143         if key in self.storing and value in self.storing[key]:
 144             if len(result) > 0:
 145                 self.storing[key][value].callback(result)
 146             else:
 147                 self.storing[key][value].errback(DHTError('could not store value %s in key %s' % (value, key)))
 148             del self.storing[key][value]
 149             if len(self.storing[key].keys()) == 0:
 150                 del self.storing[key]
 151
 152 class TestSimpleDHT(unittest.TestCase):
 153     """Unit tests for the DHT."""
 154
 155     timeout = 2
 156     DHT_DEFAULTS = {'PORT': 9977, 'K': 8, 'HASH_LENGTH': 160,
 157                     'CHECKPOINT_INTERVAL': 900, 'CONCURRENT_REQS': 4,
 158                     'STORE_REDUNDANCY': 3, 'MAX_FAILURES': 3,
 159                     'MIN_PING_INTERVAL': 900,'BUCKET_STALENESS': 3600,
 160                     'KEINITIAL_DELAY': 15, 'KE_DELAY': 1200,
 161                     'KE_AGE': 3600, }
 162
 163     def setUp(self):
 164         self.a = DHT()
 165         self.b = DHT()
 166         self.a.config = self.DHT_DEFAULTS.copy()
 167         self.a.config['PORT'] = 4044
 168         self.a.bootstrap = ["127.0.0.1:4044"]
 169         self.a.bootstrap_node = True
 170         self.a.cache_dir = '/tmp'
 171         self.b.config = self.DHT_DEFAULTS.copy()
 172         self.b.config['PORT'] = 4045
 173         self.b.bootstrap = ["127.0.0.1:4044"]
 174         self.b.cache_dir = '/tmp'
 175
 176     def test_bootstrap_join(self):
 177         d = self.a.join()
 178         return d
 179
 180     def node_join(self, result):
 181         d = self.b.join()
 182         return d
 183
 184     def test_join(self):
 185         self.lastDefer = defer.Deferred()
 186         d = self.a.join()
 187         d.addCallback(self.node_join)
 188         d.addCallback(self.lastDefer.callback)
 189         return self.lastDefer
 190
 191     def value_stored(self, result, value):
 192         self.stored -= 1
 193         if self.stored == 0:
 194             self.get_values()
 195
 196     def store_values(self, result):
 197         self.stored = 3
 198         d = self.a.storeValue(sha.new('4045').digest(), str(4045*3))
 199         d.addCallback(self.value_stored, 4045)
 200         d = self.a.storeValue(sha.new('4044').digest(), str(4044*2))
 201         d.addCallback(self.value_stored, 4044)
 202         d = self.b.storeValue(sha.new('4045').digest(), str(4045*2))
 203         d.addCallback(self.value_stored, 4045)
 204
 205     def check_values(self, result, values):
 206         self.checked -= 1
 207         self.failUnless(len(result) == len(values))
 208         for v in result:
 209             self.failUnless(v in values)
 210         if self.checked == 0:
 211             self.lastDefer.callback(1)
 212
 213     def get_values(self):
 214         self.checked = 4
 215         d = self.a.getValue(sha.new('4044').digest())
 216         d.addCallback(self.check_values, [str(4044*2)])
 217         d = self.b.getValue(sha.new('4044').digest())
 218         d.addCallback(self.check_values, [str(4044*2)])
 219         d = self.a.getValue(sha.new('4045').digest())
 220         d.addCallback(self.check_values, [str(4045*2), str(4045*3)])
 221         d = self.b.getValue(sha.new('4045').digest())
 222         d.addCallback(self.check_values, [str(4045*2), str(4045*3)])
 223
 224     def test_store(self):
 225         from twisted.internet.base import DelayedCall
 226         DelayedCall.debug = True
 227         self.lastDefer = defer.Deferred()
 228         d = self.a.join()
 229         d.addCallback(self.node_join)
 230         d.addCallback(self.store_values)
 231         return self.lastDefer
 232
 233     def tearDown(self):
 234         self.a.leave()
 235         try:
 236             os.unlink(self.a.khashmir.store.db)
 237         except:
 238             pass
 239         self.b.leave()
 240         try:
 241             os.unlink(self.b.khashmir.store.db)
 242         except:
 243             pass
 244
 245 class TestMultiDHT(unittest.TestCase):
 246
 247     timeout = 60
 248     num = 20
 249     DHT_DEFAULTS = {'PORT': 9977, 'K': 8, 'HASH_LENGTH': 160,
 250                     'CHECKPOINT_INTERVAL': 900, 'CONCURRENT_REQS': 4,
 251                     'STORE_REDUNDANCY': 3, 'MAX_FAILURES': 3,
 252                     'MIN_PING_INTERVAL': 900,'BUCKET_STALENESS': 3600,
 253                     'KEINITIAL_DELAY': 15, 'KE_DELAY': 1200,
 254                     'KE_AGE': 3600, }
 255
 256     def setUp(self):
 257         self.l = []
 258         self.startport = 4081
 259         for i in range(self.num):
 260             self.l.append(DHT())
 261             self.l[i].config = self.DHT_DEFAULTS.copy()
 262             self.l[i].config['PORT'] = self.startport + i
 263             self.l[i].bootstrap = ["127.0.0.1:" + str(self.startport)]
 264             self.l[i].cache_dir = '/tmp'
 265         self.l[0].bootstrap_node = True
 266
 267     def node_join(self, result, next_node):
 268         d = self.l[next_node].join()
 269         if next_node + 1 < len(self.l):
 270             d.addCallback(self.node_join, next_node + 1)
 271         else:
 272             d.addCallback(self.lastDefer.callback)
 273
 274     def test_join(self):
 275         self.timeout = 2
 276         self.lastDefer = defer.Deferred()
 277         d = self.l[0].join()
 278         d.addCallback(self.node_join, 1)
 279         return self.lastDefer
 280
 281     def store_values(self, result, i = 0, j = 0):
 282         if j > i:
 283             j -= i+1
 284             i += 1
 285         if i == len(self.l):
 286             self.get_values()
 287         else:
 288             d = self.l[j].storeValue(sha.new(str(self.startport+i)).digest(), str((self.startport+i)*(j+1)))
 289             d.addCallback(self.store_values, i, j+1)
 290
 291     def get_values(self, result = None, check = None, i = 0, j = 0):
 292         if result is not None:
 293             self.failUnless(len(result) == len(check))
 294             for v in result:
 295                 self.failUnless(v in check)
 296         if j >= len(self.l):
 297             j -= len(self.l)
 298             i += 1
 299         if i == len(self.l):
 300             self.lastDefer.callback(1)
 301         else:
 302             d = self.l[i].getValue(sha.new(str(self.startport+j)).digest())
 303             check = []
 304             for k in range(self.startport+j, (self.startport+j)*(j+1)+1, self.startport+j):
 305                 check.append(str(k))
 306             d.addCallback(self.get_values, check, i, j + random.randrange(1, min(len(self.l), 10)))
 307
 308     def store_join(self, result, next_node):
 309         d = self.l[next_node].join()
 310         if next_node + 1 < len(self.l):
 311             d.addCallback(self.store_join, next_node + 1)
 312         else:
 313             d.addCallback(self.store_values)
 314
 315     def test_store(self):
 316         from twisted.internet.base import DelayedCall
 317         DelayedCall.debug = True
 318         self.lastDefer = defer.Deferred()
 319         d = self.l[0].join()
 320         d.addCallback(self.store_join, 1)
 321         return self.lastDefer
 322
 323     def tearDown(self):
 324         for i in self.l:
 325             try:
 326                 i.leave()
 327                 os.unlink(i.khashmir.store.db)
 328             except:
 329                 pass