def _get_kbucket_index(self, guid):
"""
Return the index of the KBucket which is responsible for the
given guid.
Agrs:
guid: The guid for which to find the appropriate KBucket index,
as a string or unicode, in hexadecimal
Returns:
The index of the KBucket responsible for the given guid.
Raises:
BadGUIDError: The guid was no KBucket's responsibility; an
invariant has been violated, or the guid is bad.
"""
# Since the KBuckets have consecutive ID spaces,
# we do a binary search.
low, high = 0, len(self._buckets)
num_guid = util.guid_to_num(guid)
while low < high:
mid = low + (high - low) // 2
bucket = self._buckets[mid]
if bucket.range_min > num_guid:
high = mid
elif bucket.range_max <= num_guid:
low = mid + 1
else:
return mid
raise util.BadGUIDError(
"No KBucket responsible for guid {0}.".format(guid))
def _get_kbucket_index(self, guid):
"""
Return the index of the KBucket which is responsible for the
given guid.
Agrs:
guid: The guid for which to find the appropriate KBucket index,
as a string or unicode, in hexadecimal
Returns:
The index of the KBucket responsible for the given guid.
Raises:
BadGUIDError: The guid was no KBucket's responsibility; an
invariant has been violated, or the guid is bad.
"""
# Since the KBuckets have consecutive ID spaces,
# we do a binary search.
low, high = 0, len(self._buckets)
num_guid = util.guid_to_num(guid)
while low < high:
mid = low + (high - low) // 2
bucket = self._buckets[mid]
if bucket.range_min > num_guid:
high = mid
elif bucket.range_max <= num_guid:
low = mid + 1
else:
return mid
raise util.BadGUIDError("No KBucket responsible for guid {0}.".format(guid))
def test_guid_to_num(self):
test_tuples = ((0, '0000000000000000000000000000000000000000'),
(42, '000000000000000000000000000000000000002a'),
(2**constants.BIT_NODE_ID_LEN - 1,
'ffffffffffffffffffffffffffffffffffffffff'),
(2**constants.BIT_NODE_ID_LEN - 1,
'ffffffffffffffffffffffffffffffffffffffffL'),
(2**constants.BIT_NODE_ID_LEN - 1,
'0xffffffffffffffffffffffffffffffffffffffffL'))
for num, guid in test_tuples:
self.assertEqual(util.guid_to_num(guid), num)
def test_add_contact_max_recursion(self):
# Add K + 1 contacts that are so close together and to
# own_guid, that they force recursive bucket splits.
base = util.guid_to_num(self.own_guid) + 1
for i in range(constants.K + 1):
self.rt.add_contact(
self._make_contact_from_num(base + i)
)
# The actual number of KBuckets created is dependend upon K,
# so this test will probably break if K changes. In such a case,
# please update the test.
self.assertEqual(len(self.rt), 157)
def guid_in_range(self, guid):
"""
Test whether the given guid is in the range of the ID space
covered by this KBucket.
Args:
guid: The guid to test, as a string or unicode, in
hexadecimal.
Returns:
True if `guid` is in this KBucket's range, False otherwise.
"""
return self.range_min <= util.guid_to_num(guid) < self.range_max
def test_guid_to_num(self):
test_tuples = (
(0, '0000000000000000000000000000000000000000'),
(42, '000000000000000000000000000000000000002a'),
(
2**constants.BIT_NODE_ID_LEN - 1,
'ffffffffffffffffffffffffffffffffffffffff'
),
(
2**constants.BIT_NODE_ID_LEN - 1,
'ffffffffffffffffffffffffffffffffffffffffL'
),
(
2**constants.BIT_NODE_ID_LEN - 1,
'0xffffffffffffffffffffffffffffffffffffffffL'
)
)
for num, guid in test_tuples:
self.assertEqual(util.guid_to_num(guid), num)
def test_add_new_contact_and_cache(self):
# Add K + 1 contacts to initial KBucket, to force a split.
base = util.guid_to_num(self.own_guid) + 1
for i in range(constants.K):
self.rt.add_contact(
self._make_contact_from_num(base + i)
)
self.rt.add_contact(self._make_contact_from_num(self.range_max - 1))
# Create a guid that is at maximal distance from own_guid,
# thus must be at a different bucket.
self.assertEqual(len(self.rt), 2)
max_base = (2**constants.BIT_NODE_ID_LEN - 1) ^ self.own_num_guid
self.assertTrue(self.rt[0].guid_in_range(self.own_guid))
self.assertTrue(self.rt[1].guid_in_range(util.num_to_guid(max_base)))
# Add contacts to the other KBucket, until it is full.
for i in range(constants.K):
if len(self.rt[1]) == constants.K:
break
self.rt.add_contact(
self._make_contact_from_num(max_base - i)
)
# Create and add a contact that is in the range of the other
# KBucket.
new_contact = self._make_contact_from_num(max_base - constants.K)
self.rt.add_contact(new_contact)
self.assertEqual(
len(self.rt),
2,
'A KBucket not containing own_guid was split.'
)
# Assert the new contact was cached properly.
self.assertNotIn(new_contact, self.rt[0])
self.assertNotIn(new_contact, self.rt[1])
self.assertEqual([], self.rt[0].get_cached_contacts())
self.assertEqual([new_contact], self.rt[1].get_cached_contacts())
