import hash
import const
-from const import K, HASH_LENGTH
+from const import K, HASH_LENGTH, NULL_ID
from node import Node
class KTable:
- """local routing table for a kademlia like distributed hash table"""
- def __init__(self, node):
- # this is the root node, a.k.a. US!
- self.node = node
- self.buckets = [KBucket([], 0L, 2L**HASH_LENGTH)]
- self.insertNode(node)
-
- def _bucketIndexForInt(self, num):
- """the index of the bucket that should hold int"""
- return bisect_left(self.buckets, num)
-
- def findNodes(self, id):
- """
- return K nodes in our own local table closest to the ID.
- """
-
- if isinstance(id, str):
- num = hash.intify(id)
- elif isinstance(id, Node):
- num = id.num
- elif isinstance(id, int) or isinstance(id, long):
- num = id
- else:
- raise TypeError, "findNodes requires an int, string, or Node"
-
- nodes = []
- i = self._bucketIndexForInt(num)
-
- # if this node is already in our table then return it
- try:
- index = self.buckets[i].l.index(num)
- except ValueError:
- pass
- else:
- return [self.buckets[i].l[index]]
-
- # don't have the node, get the K closest nodes
- nodes = nodes + self.buckets[i].l
- if len(nodes) < K:
- # need more nodes
- min = i - 1
- max = i + 1
- while len(nodes) < K and (min >= 0 or max < len(self.buckets)):
- #ASw: note that this requires K be even
- if min >= 0:
- nodes = nodes + self.buckets[min].l
- if max < len(self.buckets):
- nodes = nodes + self.buckets[max].l
- min = min - 1
- max = max + 1
-
- nodes.sort(lambda a, b, num=num: cmp(num ^ a.num, num ^ b.num))
- return nodes[:K]
-
- def _splitBucket(self, a):
- diff = (a.max - a.min) / 2
- b = KBucket([], a.max - diff, a.max)
- self.buckets.insert(self.buckets.index(a.min) + 1, b)
- a.max = a.max - diff
- # transfer nodes to new bucket
- for anode in a.l[:]:
- if anode.num >= a.max:
- a.l.remove(anode)
- b.l.append(anode)
-
- def replaceStaleNode(self, stale, new):
- """this is used by clients to replace a node returned by insertNode after
- it fails to respond to a Pong message"""
- i = self._bucketIndexForInt(stale.num)
- try:
- it = self.buckets[i].l.index(stale.num)
- except ValueError:
- return
-
- del(self.buckets[i].l[it])
- if new:
- self.buckets[i].l.append(new)
-
- def insertNode(self, node, contacted=1):
- """
- this insert the node, returning None if successful, returns the oldest node in the bucket if it's full
- the caller responsible for pinging the returned node and calling replaceStaleNode if it is found to be stale!!
- contacted means that yes, we contacted THEM and we know the node is reachable
- """
- assert node.id != " "*20
- if node.id == self.node.id: return
- # get the bucket for this node
- i = self. _bucketIndexForInt(node.num)
- # check to see if node is in the bucket already
- try:
- it = self.buckets[i].l.index(node.num)
- except ValueError:
- # no
- pass
- else:
- if contacted:
- node.updateLastSeen()
- # move node to end of bucket
- xnode = self.buckets[i].l[it]
- del(self.buckets[i].l[it])
- # note that we removed the original and replaced it with the new one
- # utilizing this nodes new contact info
- self.buckets[i].l.append(xnode)
- self.buckets[i].touch()
- return
-
- # we don't have this node, check to see if the bucket is full
- if len(self.buckets[i].l) < K:
- # no, append this node and return
- if contacted:
- node.updateLastSeen()
- self.buckets[i].l.append(node)
- self.buckets[i].touch()
- return
-
- # bucket is full, check to see if self.node is in the bucket
- if not (self.buckets[i].min <= self.node < self.buckets[i].max):
- return self.buckets[i].l[0]
-
- # this bucket is full and contains our node, split the bucket
- if len(self.buckets) >= HASH_LENGTH:
- # our table is FULL, this is really unlikely
- print "Hash Table is FULL! Increase K!"
- return
-
- self._splitBucket(self.buckets[i])
-
- # now that the bucket is split and balanced, try to insert the node again
- return self.insertNode(node)
-
- def justSeenNode(self, node):
- """call this any time you get a message from a node
- it will update it in the table if it's there """
- try:
- n = self.findNodes(node.num)[0]
- except IndexError:
- return None
- else:
- tstamp = n.lastSeen
- n.updateLastSeen()
- return tstamp
-
- def invalidateNode(self, n):
- """
- forget about node n - use when you know that node is invalid
- """
- self.replaceStaleNode(n, None)
-
- def nodeFailed(self, node):
- """ call this when a node fails to respond to a message, to invalidate that node """
- try:
- n = self.findNodes(node.num)[0]
- except IndexError:
- return None
- else:
- if n.msgFailed() >= const.MAX_FAILURES:
- self.invalidateNode(n)
-
+ """local routing table for a kademlia like distributed hash table"""
+ def __init__(self, node):
+ # this is the root node, a.k.a. US!
+ self.node = node
+ self.buckets = [KBucket([], 0L, 2L**HASH_LENGTH)]
+ self.insertNode(node)
+
+ def _bucketIndexForInt(self, num):
+ """the index of the bucket that should hold int"""
+ return bisect_left(self.buckets, num)
+
+ def findNodes(self, id):
+ """
+ return K nodes in our own local table closest to the ID.
+ """
+
+ if isinstance(id, str):
+ num = hash.intify(id)
+ elif isinstance(id, Node):
+ num = id.num
+ elif isinstance(id, int) or isinstance(id, long):
+ num = id
+ else:
+ raise TypeError, "findNodes requires an int, string, or Node"
+
+ nodes = []
+ i = self._bucketIndexForInt(num)
+
+ # if this node is already in our table then return it
+ try:
+ index = self.buckets[i].l.index(num)
+ except ValueError:
+ pass
+ else:
+ return [self.buckets[i].l[index]]
+
+ # don't have the node, get the K closest nodes
+ nodes = nodes + self.buckets[i].l
+ if len(nodes) < K:
+ # need more nodes
+ min = i - 1
+ max = i + 1
+ while len(nodes) < K and (min >= 0 or max < len(self.buckets)):
+ #ASw: note that this requires K be even
+ if min >= 0:
+ nodes = nodes + self.buckets[min].l
+ if max < len(self.buckets):
+ nodes = nodes + self.buckets[max].l
+ min = min - 1
+ max = max + 1
+
+ nodes.sort(lambda a, b, num=num: cmp(num ^ a.num, num ^ b.num))
+ return nodes[:K]
+
+ def _splitBucket(self, a):
+ diff = (a.max - a.min) / 2
+ b = KBucket([], a.max - diff, a.max)
+ self.buckets.insert(self.buckets.index(a.min) + 1, b)
+ a.max = a.max - diff
+ # transfer nodes to new bucket
+ for anode in a.l[:]:
+ if anode.num >= a.max:
+ a.l.remove(anode)
+ b.l.append(anode)
+
+ def replaceStaleNode(self, stale, new):
+ """this is used by clients to replace a node returned by insertNode after
+ it fails to respond to a Pong message"""
+ i = self._bucketIndexForInt(stale.num)
+ try:
+ it = self.buckets[i].l.index(stale.num)
+ except ValueError:
+ return
+
+ del(self.buckets[i].l[it])
+ if new:
+ self.buckets[i].l.append(new)
+
+ def insertNode(self, node, contacted=1):
+ """
+ this insert the node, returning None if successful, returns the oldest node in the bucket if it's full
+ the caller responsible for pinging the returned node and calling replaceStaleNode if it is found to be stale!!
+ contacted means that yes, we contacted THEM and we know the node is reachable
+ """
+ assert node.id != NULL_ID
+ if node.id == self.node.id: return
+ # get the bucket for this node
+ i = self. _bucketIndexForInt(node.num)
+ # check to see if node is in the bucket already
+ try:
+ it = self.buckets[i].l.index(node.num)
+ except ValueError:
+ # no
+ pass
+ else:
+ if contacted:
+ node.updateLastSeen()
+ # move node to end of bucket
+ xnode = self.buckets[i].l[it]
+ del(self.buckets[i].l[it])
+ # note that we removed the original and replaced it with the new one
+ # utilizing this nodes new contact info
+ self.buckets[i].l.append(xnode)
+ self.buckets[i].touch()
+ return
+
+ # we don't have this node, check to see if the bucket is full
+ if len(self.buckets[i].l) < K:
+ # no, append this node and return
+ if contacted:
+ node.updateLastSeen()
+ self.buckets[i].l.append(node)
+ self.buckets[i].touch()
+ return
+
+ # bucket is full, check to see if self.node is in the bucket
+ if not (self.buckets[i].min <= self.node < self.buckets[i].max):
+ return self.buckets[i].l[0]
+
+ # this bucket is full and contains our node, split the bucket
+ if len(self.buckets) >= HASH_LENGTH:
+ # our table is FULL, this is really unlikely
+ print "Hash Table is FULL! Increase K!"
+ return
+
+ self._splitBucket(self.buckets[i])
+
+ # now that the bucket is split and balanced, try to insert the node again
+ return self.insertNode(node)
+
+ def justSeenNode(self, id):
+ """call this any time you get a message from a node
+ it will update it in the table if it's there """
+ try:
+ n = self.findNodes(id)[0]
+ except IndexError:
+ return None
+ else:
+ tstamp = n.lastSeen
+ n.updateLastSeen()
+ return tstamp
+
+ def invalidateNode(self, n):
+ """
+ forget about node n - use when you know that node is invalid
+ """
+ self.replaceStaleNode(n, None)
+
+ def nodeFailed(self, node):
+ """ call this when a node fails to respond to a message, to invalidate that node """
+ try:
+ n = self.findNodes(node.num)[0]
+ except IndexError:
+ return None
+ else:
+ if n.msgFailed() >= const.MAX_FAILURES:
+ self.invalidateNode(n)
+
class KBucket:
- __slots__ = ('min', 'max', 'lastAccessed')
- def __init__(self, contents, min, max):
- self.l = contents
- self.min = min
- self.max = max
- self.lastAccessed = time.time()
-
- def touch(self):
- self.lastAccessed = time.time()
-
- def getNodeWithInt(self, num):
- if num in self.l: return num
- else: raise ValueError
-
- def __repr__(self):
- return "<KBucket %d items (%d to %d)>" % (len(self.l), self.min, self.max)
-
- ## Comparators
- # necessary for bisecting list of buckets with a hash expressed as an integer or a distance
- # compares integer or node object with the bucket's range
- def __lt__(self, a):
- if isinstance(a, Node): a = a.num
- return self.max <= a
- def __le__(self, a):
- if isinstance(a, Node): a = a.num
- return self.min < a
- def __gt__(self, a):
- if isinstance(a, Node): a = a.num
- return self.min > a
- def __ge__(self, a):
- if isinstance(a, Node): a = a.num
- return self.max >= a
- def __eq__(self, a):
- if isinstance(a, Node): a = a.num
- return self.min <= a and self.max > a
- def __ne__(self, a):
- if isinstance(a, Node): a = a.num
- return self.min >= a or self.max < a
+ __slots__ = ('min', 'max', 'lastAccessed')
+ def __init__(self, contents, min, max):
+ self.l = contents
+ self.min = min
+ self.max = max
+ self.lastAccessed = time.time()
+
+ def touch(self):
+ self.lastAccessed = time.time()
+
+ def getNodeWithInt(self, num):
+ if num in self.l: return num
+ else: raise ValueError
+
+ def __repr__(self):
+ return "<KBucket %d items (%d to %d)>" % (len(self.l), self.min, self.max)
+
+ ## Comparators
+ # necessary for bisecting list of buckets with a hash expressed as an integer or a distance
+ # compares integer or node object with the bucket's range
+ def __lt__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.max <= a
+ def __le__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.min < a
+ def __gt__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.min > a
+ def __ge__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.max >= a
+ def __eq__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.min <= a and self.max > a
+ def __ne__(self, a):
+ if isinstance(a, Node): a = a.num
+ return self.min >= a or self.max < a
### UNIT TESTS ###
def setUp(self):
self.a = Node().init(hash.newID(), 'localhost', 2002)
self.t = KTable(self.a)
- print self.t.buckets[0].l
- def test_replace_stale_node(self):
+ def testAddNode(self):
self.b = Node().init(hash.newID(), 'localhost', 2003)
- self.t.replaceStaleNode(self.a, self.b)
- assert len(self.t.buckets[0].l) == 1
- assert self.t.buckets[0].l[0].id == self.b.id
+ self.t.insertNode(self.b)
+ self.assertEqual(len(self.t.buckets[0].l), 1)
+ self.assertEqual(self.t.buckets[0].l[0], self.b)
+
+ def testRemove(self):
+ self.testAddNode()
+ self.t.invalidateNode(self.b)
+ self.assertEqual(len(self.t.buckets[0].l), 0)
+
+ def testFail(self):
+ self.testAddNode()
+ for i in range(const.MAX_FAILURES - 1):
+ self.t.nodeFailed(self.b)
+ self.assertEqual(len(self.t.buckets[0].l), 1)
+ self.assertEqual(self.t.buckets[0].l[0], self.b)
+
+ self.t.nodeFailed(self.b)
+ self.assertEqual(len(self.t.buckets[0].l), 0)
+
if __name__ == "__main__":
unittest.main()
projects / quix0rs-apt-p2p.git / blobdiff