def testDifferenceBwOversizedIblts(self):
# Insert 50 elements into an IBLT of size 10. Then check that we can
# still list the difference even though we can't list the IBLT itself.
size = 10
ownIblt = InvertibleBloomLookupTable(size)
for i in range(50):
prefix = Name("/test/memphis" + str(i)).appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
ownIblt.insert(newHash)
receivedIblt = InvertibleBloomLookupTable(ownIblt)
prefix = Name("/test/ucla").appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
ownIblt.insert(newHash)
diff = ownIblt.difference(receivedIblt)
positive = set()
negative = set()
self.assertTrue(diff.listEntries(positive, negative))
self.assertEqual(1, len(positive))
self.assertEqual(newHash, min(positive))
self.assertEqual(0, len(negative))
self.assertTrue(not ownIblt.listEntries(positive, negative))
self.assertTrue(not receivedIblt.listEntries(positive, negative))
def testDifference(self):
size = 10
ownIblt = InvertibleBloomLookupTable(size)
receivedIblt = InvertibleBloomLookupTable(ownIblt)
diff = ownIblt.difference(receivedIblt)
# Non-empty positive means we have some elements that the other doesn't.
positive = set()
negative = set()
self.assertTrue(diff.listEntries(positive, negative))
self.assertEqual(0, len(positive))
self.assertEqual(0, len(negative))
prefix = Name("/test/memphis").appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
ownIblt.insert(newHash)
diff = ownIblt.difference(receivedIblt)
self.assertTrue(diff.listEntries(positive, negative))
self.assertEqual(1, len(positive))
self.assertEqual(0, len(negative))
prefix = Name("/test/csu").appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
receivedIblt.insert(newHash)
diff = ownIblt.difference(receivedIblt)
self.assertTrue(diff.listEntries(positive, negative))
self.assertEqual(1, len(positive))
self.assertEqual(1, len(negative))
def testHigherSequence(self):
# This is the case where we can't recognize if the received IBF has a
# higher sequence number. This is relevant to the full sync case.
size = 10
ownIblt = InvertibleBloomLookupTable(size)
receivedIblt = InvertibleBloomLookupTable(size)
prefix = Name("/test/memphis").appendNumber(3).toUri()
hash1 = Common.murmurHash3Blob(11, prefix)
ownIblt.insert(hash1)
prefix2 = Name("/test/memphis").appendNumber(4).toUri()
hash2 = Common.murmurHash3Blob(11, prefix2)
receivedIblt.insert(hash2)
diff = ownIblt.difference(receivedIblt)
positive = set()
negative = set()
self.assertTrue(diff.listEntries(positive, negative))
self.assertEqual(1, len(positive))
self.assertTrue(min(positive) == hash1)
self.assertEqual(1, len(negative))
self.assertTrue(min(negative) == hash2)
def testNameAppendAndExtract(self):
size = 10
iblt = InvertibleBloomLookupTable(size)
prefix = Name("/test/memphis").appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
iblt.insert(newHash)
expectedEncoding = [
0x78, 0xda, 0x63, 0x64, 0x60, 0x60, 0xd8, 0x55, 0xb5, 0xfc, 0x5b,
0xb2, 0xef, 0xe2, 0x6c, 0x06, 0x0a, 0x00, 0x23, 0x1d, 0xcd, 0x01,
0x00, 0x65, 0x29, 0x0d, 0xb1
]
ibltName = Name("sync")
encodedIblt = iblt.encode()
self.assertTrue(encodedIblt.equals(Blob(expectedEncoding)))
ibltName.append(encodedIblt)
received = InvertibleBloomLookupTable(size)
received.initialize(ibltName.get(-1).getValue())
self.assertTrue(iblt.equals(received))
receivedDifferentSize = InvertibleBloomLookupTable(20)
try:
receivedDifferentSize.initialize(ibltName.get(-1).getValue())
self.fail("Did not throw the expected exception")
except RuntimeError:
pass
else:
self.fail("Did not throw the expected exception")
def testCopyInsertErase(self):
size = 10
iblt1 = InvertibleBloomLookupTable(size)
prefix = Name("/test/memphis").appendNumber(1).toUri()
hash1 = Common.murmurHash3Blob(11, prefix)
iblt1.insert(hash1)
iblt2 = InvertibleBloomLookupTable(iblt1)
iblt2.erase(hash1)
prefix = Name("/test/memphis").appendNumber(2).toUri()
hash3 = Common.murmurHash3Blob(11, prefix)
iblt2.insert(hash3)
iblt1.erase(hash1)
prefix = Name("/test/memphis").appendNumber(5).toUri()
hash5 = Common.murmurHash3Blob(11, prefix)
iblt1.insert(hash5)
iblt2.erase(hash3)
iblt2.insert(hash5)
self.assertTrue(iblt1.equals(iblt2))
def testEqual(self):
size = 10
iblt1 = InvertibleBloomLookupTable(size)
iblt2 = InvertibleBloomLookupTable(size)
self.assertTrue(iblt1.equals(iblt2))
prefix = Name("/test/memphis").appendNumber(1).toUri()
newHash = Common.murmurHash3Blob(11, prefix)
iblt1.insert(newHash)
iblt2.insert(newHash)
self.assertTrue(iblt1.equals(iblt2))
ibfName1 = Name("/sync")
ibfName2 = Name("/sync")
ibfName1.append(iblt1.encode())
ibfName2.append(iblt2.encode())
self.assertTrue(ibfName1.equals(ibfName2))
def _isNotFutureHash(self, name, negative):
"""
Get the prefix from the name and check if hash(prefix + 1) is in the
negative set. (Sometimes the Interest from the other side gets to us
before the Data.)
:param Name name: The Name to check.
:param Set<int> negative: The negative set of hashes.
:return: True if hash(prefix + 1) is NOT in the negative set (meaning
that it is not a future hash), or False if it IS in the negative set.
:rtype: bool
"""
prefix = name.getPrefix(-1)
uri = Name(prefix).appendNumber(
self._prefixes._prefixes.get(prefix, 0) + 1).toUri()
nextHash = Common.murmurHash3Blob(
InvertibleBloomLookupTable.N_HASHCHECK, uri)
for negativeHash in negative:
if negativeHash == nextHash:
return False
return True
def _isNotFutureHash(self, name, negative):
"""
Get the prefix from the name and check if hash(prefix + 1) is in the
negative set. (Sometimes the Interest from the other side gets to us
before the Data.)
:param Name name: The Name to check.
:param Set<int> negative: The negative set of hashes.
:return: True if hash(prefix + 1) is NOT in the negative set (meaning
that it is not a future hash), or False if it IS in the negative set.
:rtype: bool
"""
prefix = name.getPrefix(-1)
uri = Name(prefix).appendNumber(
self._prefixes._prefixes.get(prefix, 0) + 1).toUri()
nextHash = Common.murmurHash3Blob(
InvertibleBloomLookupTable.N_HASHCHECK, uri)
for negativeHash in negative:
if negativeHash == nextHash:
return False
return True
