apt_dht_Khashmir/DHT.py

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