def _get_hashes(key, filters_params):
params_true, params_false = filters_params
index_size_true, number_of_hashes_true = params_true
index_size_false, number_of_hashes_false = params_false
hashes_true = get_hashes(key + "true", number_of_hashes_true,
index_size_true)
hashes_false = get_hashes(key + "false", number_of_hashes_false,
index_size_false)
return hashes_true, hashes_false
async def __set(*args: Any, **kwargs: Any):
if _set is None:
result = await func(*args, **kwargs)
else:
result = await _set(*args, **kwargs)
if not result:
return result
_bloom_key = get_cache_key(func, _name, args, kwargs)
hashes = get_hashes(_bloom_key, number_of_hashes, index_size)
await backend.incr_bits(_cache_key, *hashes)
return result
async def _wrap(*args, **kwargs):
_bloom_key = get_cache_key(func, _name, args, kwargs)
hashes = get_hashes(_bloom_key, number_of_hashes, index_size)
values = await backend.get_bits(_cache_key, *hashes)
if values is None:
return await func(*args, **kwargs)
if all_not_zeros(values): # if all bits is set
# false positive
if check_false_positive:
return await func(*args, **kwargs)
return True
else:
return False
async def _wrap(*args, **kwargs):
_bloom_key = get_cache_key(func, _name, args, kwargs)
hashes = get_hashes(_bloom_key, number_of_hashes, index_size)
values = await backend.get_bits(_cache_key, *hashes, size=2)
if at_least_one_zero(values):
return False
if all(values):
if not check_false_positive:
return True
result = await func(*args, **kwargs)
assert isinstance(result, bool)
if result:
await backend.incr_bits(_cache_key, *hashes, size=2, by=3)
else:
await backend.incr_bits(_cache_key, *hashes, size=2, by=1)
return result
def test_get_hashes():
assert get_hashes("test", 10, 1000) == get_hashes("test", 10, 1000)
assert get_hashes("test", 2, 2) == get_hashes("test", 2, 2)
assert get_hashes("test", 2, 5) != get_hashes("test", 2, 2)
assert get_hashes("test", 3, 100) != get_hashes("tset", 3, 100)
assert get_hashes("test", 3, 100) != get_hashes("t", 3, 100)
assert get_hashes("test", 3, 100) != get_hashes("tes", 3, 100)
assert get_hashes("test", 3, 100) != get_hashes("test2", 3, 100)
assert not get_hashes("test", 5, 100).intersection(get_hashes("a", 5, 100))
assert not get_hashes("test", 5, 100).intersection(get_hashes("test2", 5, 100))
assert get_hashes("test", 3, 3) == get_hashes("a", 3, 3) # it is ok to have collisions in this case
assert len(get_hashes("test", 20, 100)) == len(set(get_hashes("test", 20, 100)))
def test_get_hashes_params():
assert len(get_hashes("test", 3, 3)) == 3
assert len(get_hashes("test", 1, 100)) == 1
assert len(get_hashes("test", 77, 100)) == 77
assert len(get_hashes("long string hash", 77, 100)) == 77
assert get_hashes("test", 1, 100).pop() < 100
async def _set(*args: Any, **kwargs: Any) -> None:
_bloom_key = get_cache_key(func, _name, args, kwargs)
hashes = get_hashes(_bloom_key, number_of_hashes, index_size)
await backend.incr_bits(_cache_key, *hashes, size=2, by=1)