class Serialization(unittest.TestCase):
SIZE = 12345
EXPECTED = set([random.randint(0, 10000100) for _ in range_fn(SIZE)])
def test_serialization(self):
for klass, args in [(BloomFilter, (self.SIZE, )),
(ScalableBloomFilter, ())]:
filter = klass(*args)
for item in self.EXPECTED:
filter.add(item)
f = tempfile.TemporaryFile()
filter.tofile(f)
stringio = StringIO()
filter.tofile(stringio)
streams_to_test = [f, stringio]
if not running_python_3:
cstringio = cStringIO.StringIO()
filter.tofile(cstringio)
streams_to_test.append(cstringio)
del filter
for stream in streams_to_test:
stream.seek(0)
filter = klass.fromfile(stream)
for item in self.EXPECTED:
self.assertTrue(item in filter)
del (filter)
stream.close()
def test_union(self):
bloom_one = BloomFilter(100, 0.001)
bloom_two = BloomFilter(100, 0.001)
chars = [chr(i) for i in range_fn(97, 123)]
for char in chars[int(len(chars)/2):]:
bloom_one.add(char)
for char in chars[:int(len(chars)/2)]:
bloom_two.add(char)
new_bloom = bloom_one.union(bloom_two)
for char in chars:
self.assertTrue(char in new_bloom)
def test_union(self):
bloom_one = BloomFilter(100, 0.001)
bloom_two = BloomFilter(100, 0.001)
chars = [chr(i) for i in range_fn(97, 123)]
for char in chars[int(len(chars) / 2):]:
bloom_one.add(char)
for char in chars[:int(len(chars) / 2)]:
bloom_two.add(char)
new_bloom = bloom_one.union(bloom_two)
for char in chars:
self.assertTrue(char in new_bloom)
def make_hashfuncs(num_slices, num_bits):
if num_bits >= (1 << 31):
fmt_code, chunk_size = 'Q', 8
elif num_bits >= (1 << 15):
fmt_code, chunk_size = 'I', 4
else:
fmt_code, chunk_size = 'H', 2
total_hash_bits = 8 * num_slices * chunk_size
if total_hash_bits > 384:
hashfn = hashlib.sha512
elif total_hash_bits > 256:
hashfn = hashlib.sha384
elif total_hash_bits > 160:
hashfn = hashlib.sha256
elif total_hash_bits > 128:
hashfn = hashlib.sha1
else:
hashfn = hashlib.md5
fmt = fmt_code * (hashfn().digest_size // chunk_size)
num_salts, extra = divmod(num_slices, len(fmt))
if extra:
num_salts += 1
salts = tuple(
hashfn(hashfn(pack('I', i)).digest()) for i in range_fn(num_salts))
def _make_hashfuncs(key):
if running_python_3:
if isinstance(key, str):
key = key.encode('utf-8')
else:
key = str(key).encode('utf-8')
else:
if isinstance(key, unicode):
key = key.encode('utf-8')
else:
key = str(key)
i = 0
for salt in salts:
h = salt.copy()
h.update(key)
for uint in unpack(fmt, h.digest()):
yield uint % num_bits
i += 1
if i >= num_slices:
return
return _make_hashfuncs
def make_hashfuncs(num_slices, num_bits):
if num_bits >= (1 << 31):
fmt_code, chunk_size = 'Q', 8
elif num_bits >= (1 << 15):
fmt_code, chunk_size = 'I', 4
else:
fmt_code, chunk_size = 'H', 2
total_hash_bits = 8 * num_slices * chunk_size
if total_hash_bits > 384:
hashfn = hashlib.sha512
elif total_hash_bits > 256:
hashfn = hashlib.sha384
elif total_hash_bits > 160:
hashfn = hashlib.sha256
elif total_hash_bits > 128:
hashfn = hashlib.sha1
else:
hashfn = hashlib.md5
fmt = fmt_code * (hashfn().digest_size // chunk_size)
num_salts, extra = divmod(num_slices, len(fmt))
if extra:
num_salts += 1
salts = tuple(hashfn(hashfn(pack('I', i)).digest()) for i in range_fn(num_salts))
def _make_hashfuncs(key):
if running_python_3:
if isinstance(key, str):
key = key.encode('utf-8')
else:
key = str(key).encode('utf-8')
else:
if isinstance(key, unicode):
key = key.encode('utf-8')
else:
key = str(key)
i = 0
for salt in salts:
h = salt.copy()
h.update(key)
for uint in unpack(fmt, h.digest()):
yield uint % num_bits
i += 1
if i >= num_slices:
return
return _make_hashfuncs
