apt_dht_Khashmir/DHT.py

   1
   2 from datetime import datetime
   3 import os, sha, random
   4
   5 from twisted.internet import defer, reactor
   6 from twisted.internet.abstract import isIPAddress
   7 from twisted.python import log
   8 from twisted.trial import unittest
   9 from zope.interface import implements
  10
  11 from apt_dht.interfaces import IDHT
  12 from khashmir import Khashmir
  13
  14 class DHTError(Exception):
  15     """Represents errors that occur in the DHT."""
  16
  17 class DHT:
  18
  19     implements(IDHT)
  20
  21     def __init__(self):
  22         self.config = None
  23         self.cache_dir = ''
  24         self.bootstrap = []
  25         self.bootstrap_node = False
  26         self.joining = None
  27         self.joined = False
  28         self.outstandingJoins = 0
  29         self.foundAddrs = []
  30         self.storing = {}
  31         self.retrieving = {}
  32         self.retrieved = {}
  33
  34     def loadConfig(self, config, section):
  35         """See L{apt_dht.interfaces.IDHT}."""
  36         self.config_parser = config
  37         self.section = section
  38         self.config = {}
  39         self.cache_dir = self.config_parser.get(section, 'cache_dir')
  40         self.bootstrap = self.config_parser.getstringlist(section, 'BOOTSTRAP')
  41         self.bootstrap_node = self.config_parser.getboolean(section, 'BOOTSTRAP_NODE')
  42         for k in self.config_parser.options(section):
  43             if k in ['K', 'HASH_LENGTH', 'CONCURRENT_REQS', 'STORE_REDUNDANCY',
  44                      'MAX_FAILURES', 'PORT']:
  45                 self.config[k] = self.config_parser.getint(section, k)
  46             elif k in ['CHECKPOINT_INTERVAL', 'MIN_PING_INTERVAL',
  47                        'BUCKET_STALENESS', 'KEINITIAL_DELAY', 'KE_DELAY', 'KE_AGE']:
  48                 self.config[k] = self.config_parser.gettime(section, k)
  49             elif k in ['SPEW']:
  50                 self.config[k] = self.config_parser.getboolean(section, k)
  51             else:
  52                 self.config[k] = self.config_parser.get(section, k)
  53
  54     def join(self):
  55         """See L{apt_dht.interfaces.IDHT}."""
  56         if self.config is None:
  57             raise DHTError, "configuration not loaded"
  58         if self.joining:
  59             raise DHTError, "a join is already in progress"
  60
  61         self.khashmir = Khashmir(self.config, self.cache_dir)
  62
  63         self.joining = defer.Deferred()
  64         for node in self.bootstrap:
  65             host, port = node.rsplit(':', 1)
  66             port = int(port)
  67             if isIPAddress(host):
  68                 self._join_gotIP(host, port)
  69             else:
  70                 reactor.resolve(host).addCallback(self._join_gotIP, port)
  71
  72         return self.joining
  73
  74     def _join_gotIP(self, ip, port):
  75         """Called after an IP address has been found for a single bootstrap node."""
  76         self.outstandingJoins += 1
  77         self.khashmir.addContact(ip, port, self._join_single, self._join_error)
  78
  79     def _join_single(self, addr):
  80         """Called when a single bootstrap node has been added."""
  81         self.outstandingJoins -= 1
  82         if addr:
  83             self.foundAddrs.append(addr)
  84         if addr or self.outstandingJoins <= 0:
  85             self.khashmir.findCloseNodes(self._join_complete, self._join_complete)
  86         log.msg('Got back from bootstrap node: %r' % (addr,))
  87
  88     def _join_error(self, failure = None):
  89         """Called when a single bootstrap node has failed."""
  90         self.outstandingJoins -= 1
  91         log.msg("bootstrap node could not be reached")
  92         if self.outstandingJoins <= 0:
  93             self.khashmir.findCloseNodes(self._join_complete, self._join_complete)
  94
  95     def _join_complete(self, result):
  96         """Called when the tables have been initialized with nodes."""
  97         if not self.joined and len(result) > 0:
  98             self.joined = True
  99         if self.joining and self.outstandingJoins <= 0:
 100             df = self.joining
 101             self.joining = None
 102             if self.joined or self.bootstrap_node:
 103                 self.joined = True
 104                 df.callback(self.foundAddrs)
 105             else:
 106                 df.errback(DHTError('could not find any nodes to bootstrap to'))
 107
 108     def getAddrs(self):
 109         return self.foundAddrs
 110
 111     def leave(self):
 112         """See L{apt_dht.interfaces.IDHT}."""
 113         if self.config is None:
 114             raise DHTError, "configuration not loaded"
 115
 116         if self.joined or self.joining:
 117             if self.joining:
 118                 self.joining.errback(DHTError('still joining when leave was called'))
 119                 self.joining = None
 120             self.joined = False
 121             self.khashmir.shutdown()
 122
 123     def getValue(self, key):
 124         """See L{apt_dht.interfaces.IDHT}."""
 125         if self.config is None:
 126             raise DHTError, "configuration not loaded"
 127         if not self.joined:
 128             raise DHTError, "have not joined a network yet"
 129
 130         d = defer.Deferred()
 131         if key not in self.retrieving:
 132             self.khashmir.valueForKey(key, self._getValue)
 133         self.retrieving.setdefault(key, []).append(d)
 134         return d
 135
 136     def _getValue(self, key, result):
 137         if result:
 138             self.retrieved.setdefault(key, []).extend(result)
 139         else:
 140             final_result = []
 141             if key in self.retrieved:
 142                 final_result = self.retrieved[key]
 143                 del self.retrieved[key]
 144             for i in range(len(self.retrieving[key])):
 145                 d = self.retrieving[key].pop(0)
 146                 d.callback(final_result)
 147             del self.retrieving[key]
 148
 149     def storeValue(self, key, value, originated = None):
 150         """See L{apt_dht.interfaces.IDHT}."""
 151         if self.config is None:
 152             raise DHTError, "configuration not loaded"
 153         if not self.joined:
 154             raise DHTError, "have not joined a network yet"
 155
 156         if key in self.storing and value in self.storing[key]:
 157             raise DHTError, "already storing that key with the same value"
 158
 159         if originated is None:
 160             originated = datetime.utcnow()
 161         d = defer.Deferred()
 162         self.khashmir.storeValueForKey(key, value, originated, self._storeValue)
 163         self.storing.setdefault(key, {})[value] = d
 164         return d
 165
 166     def _storeValue(self, key, value, result):
 167         if key in self.storing and value in self.storing[key]:
 168             if len(result) > 0:
 169                 self.storing[key][value].callback(result)
 170             else:
 171                 self.storing[key][value].errback(DHTError('could not store value %s in key %s' % (value, key)))
 172             del self.storing[key][value]
 173             if len(self.storing[key].keys()) == 0:
 174                 del self.storing[key]
 175
 176 class TestSimpleDHT(unittest.TestCase):
 177     """Unit tests for the DHT."""
 178
 179     timeout = 2
 180     DHT_DEFAULTS = {'PORT': 9977, 'K': 8, 'HASH_LENGTH': 160,
 181                     'CHECKPOINT_INTERVAL': 900, 'CONCURRENT_REQS': 4,
 182                     'STORE_REDUNDANCY': 3, 'MAX_FAILURES': 3,
 183                     'MIN_PING_INTERVAL': 900,'BUCKET_STALENESS': 3600,
 184                     'KEINITIAL_DELAY': 15, 'KE_DELAY': 1200,
 185                     'KE_AGE': 3600, 'SPEW': True, }
 186
 187     def setUp(self):
 188         self.a = DHT()
 189         self.b = DHT()
 190         self.a.config = self.DHT_DEFAULTS.copy()
 191         self.a.config['PORT'] = 4044
 192         self.a.bootstrap = ["127.0.0.1:4044"]
 193         self.a.bootstrap_node = True
 194         self.a.cache_dir = '/tmp'
 195         self.b.config = self.DHT_DEFAULTS.copy()
 196         self.b.config['PORT'] = 4045
 197         self.b.bootstrap = ["127.0.0.1:4044"]
 198         self.b.cache_dir = '/tmp'
 199
 200     def test_bootstrap_join(self):
 201         d = self.a.join()
 202         return d
 203
 204     def node_join(self, result):
 205         d = self.b.join()
 206         return d
 207
 208     def test_join(self):
 209         self.lastDefer = defer.Deferred()
 210         d = self.a.join()
 211         d.addCallback(self.node_join)
 212         d.addCallback(self.lastDefer.callback)
 213         return self.lastDefer
 214
 215     def value_stored(self, result, value):
 216         self.stored -= 1
 217         if self.stored == 0:
 218             self.get_values()
 219
 220     def store_values(self, result):
 221         self.stored = 3
 222         d = self.a.storeValue(sha.new('4045').digest(), str(4045*3))
 223         d.addCallback(self.value_stored, 4045)
 224         d = self.a.storeValue(sha.new('4044').digest(), str(4044*2))
 225         d.addCallback(self.value_stored, 4044)
 226         d = self.b.storeValue(sha.new('4045').digest(), str(4045*2))
 227         d.addCallback(self.value_stored, 4045)
 228
 229     def check_values(self, result, values):
 230         self.checked -= 1
 231         self.failUnless(len(result) == len(values))
 232         for v in result:
 233             self.failUnless(v in values)
 234         if self.checked == 0:
 235             self.lastDefer.callback(1)
 236
 237     def get_values(self):
 238         self.checked = 4
 239         d = self.a.getValue(sha.new('4044').digest())
 240         d.addCallback(self.check_values, [str(4044*2)])
 241         d = self.b.getValue(sha.new('4044').digest())
 242         d.addCallback(self.check_values, [str(4044*2)])
 243         d = self.a.getValue(sha.new('4045').digest())
 244         d.addCallback(self.check_values, [str(4045*2), str(4045*3)])
 245         d = self.b.getValue(sha.new('4045').digest())
 246         d.addCallback(self.check_values, [str(4045*2), str(4045*3)])
 247
 248     def test_store(self):
 249         from twisted.internet.base import DelayedCall
 250         DelayedCall.debug = True
 251         self.lastDefer = defer.Deferred()
 252         d = self.a.join()
 253         d.addCallback(self.node_join)
 254         d.addCallback(self.store_values)
 255         return self.lastDefer
 256
 257     def tearDown(self):
 258         self.a.leave()
 259         try:
 260             os.unlink(self.a.khashmir.store.db)
 261         except:
 262             pass
 263         self.b.leave()
 264         try:
 265             os.unlink(self.b.khashmir.store.db)
 266         except:
 267             pass
 268
 269 class TestMultiDHT(unittest.TestCase):
 270
 271     timeout = 60
 272     num = 20
 273     DHT_DEFAULTS = {'PORT': 9977, 'K': 8, 'HASH_LENGTH': 160,
 274                     'CHECKPOINT_INTERVAL': 900, 'CONCURRENT_REQS': 4,
 275                     'STORE_REDUNDANCY': 3, 'MAX_FAILURES': 3,
 276                     'MIN_PING_INTERVAL': 900,'BUCKET_STALENESS': 3600,
 277                     'KEINITIAL_DELAY': 15, 'KE_DELAY': 1200,
 278                     'KE_AGE': 3600, 'SPEW': False, }
 279
 280     def setUp(self):
 281         self.l = []
 282         self.startport = 4081
 283         for i in range(self.num):
 284             self.l.append(DHT())
 285             self.l[i].config = self.DHT_DEFAULTS.copy()
 286             self.l[i].config['PORT'] = self.startport + i
 287             self.l[i].bootstrap = ["127.0.0.1:" + str(self.startport)]
 288             self.l[i].cache_dir = '/tmp'
 289         self.l[0].bootstrap_node = True
 290
 291     def node_join(self, result, next_node):
 292         d = self.l[next_node].join()
 293         if next_node + 1 < len(self.l):
 294             d.addCallback(self.node_join, next_node + 1)
 295         else:
 296             d.addCallback(self.lastDefer.callback)
 297
 298     def test_join(self):
 299         self.timeout = 2
 300         self.lastDefer = defer.Deferred()
 301         d = self.l[0].join()
 302         d.addCallback(self.node_join, 1)
 303         return self.lastDefer
 304
 305     def store_values(self, result, i = 0, j = 0):
 306         if j > i:
 307             j -= i+1
 308             i += 1
 309         if i == len(self.l):
 310             self.get_values()
 311         else:
 312             d = self.l[j].storeValue(sha.new(str(self.startport+i)).digest(), str((self.startport+i)*(j+1)))
 313             d.addCallback(self.store_values, i, j+1)
 314
 315     def get_values(self, result = None, check = None, i = 0, j = 0):
 316         if result is not None:
 317             self.failUnless(len(result) == len(check))
 318             for v in result:
 319                 self.failUnless(v in check)
 320         if j >= len(self.l):
 321             j -= len(self.l)
 322             i += 1
 323         if i == len(self.l):
 324             self.lastDefer.callback(1)
 325         else:
 326             d = self.l[i].getValue(sha.new(str(self.startport+j)).digest())
 327             check = []
 328             for k in range(self.startport+j, (self.startport+j)*(j+1)+1, self.startport+j):
 329                 check.append(str(k))
 330             d.addCallback(self.get_values, check, i, j + random.randrange(1, min(len(self.l), 10)))
 331
 332     def store_join(self, result, next_node):
 333         d = self.l[next_node].join()
 334         if next_node + 1 < len(self.l):
 335             d.addCallback(self.store_join, next_node + 1)
 336         else:
 337             d.addCallback(self.store_values)
 338
 339     def test_store(self):
 340         from twisted.internet.base import DelayedCall
 341         DelayedCall.debug = True
 342         self.lastDefer = defer.Deferred()
 343         d = self.l[0].join()
 344         d.addCallback(self.store_join, 1)
 345         return self.lastDefer
 346
 347     def tearDown(self):
 348         for i in self.l:
 349             try:
 350                 i.leave()
 351                 os.unlink(i.khashmir.store.db)
 352             except:
 353                 pass