move add peer logic to routing table

This commit is contained in:
Victor Shyba 2022-07-11 02:38:55 -03:00
parent 0d343ecb2f
commit 972db80246
2 changed files with 74 additions and 82 deletions

View file

@ -356,72 +356,10 @@ class KademliaProtocol(DatagramProtocol):
return args, {} return args, {}
async def _add_peer(self, peer: 'KademliaPeer'): async def _add_peer(self, peer: 'KademliaPeer'):
if not peer.node_id: async def probe(some_peer: 'KademliaPeer'):
log.warning("Tried adding a peer with no node id!") rpc_peer = self.get_rpc_peer(some_peer)
return False await rpc_peer.ping()
for my_peer in self.routing_table.get_peers(): return await self.routing_table.add_peer(peer, probe)
if (my_peer.address, my_peer.udp_port) == (peer.address, peer.udp_port) and my_peer.node_id != peer.node_id:
self.routing_table.remove_peer(my_peer)
self.routing_table.join_buckets()
bucket_index = self.routing_table.kbucket_index(peer.node_id)
if self.routing_table.buckets[bucket_index].add_peer(peer):
return True
# The bucket is full; see if it can be split (by checking if its range includes the host node's node_id)
if self.routing_table.should_split(bucket_index, peer.node_id):
self.routing_table.split_bucket(bucket_index)
# Retry the insertion attempt
result = await self._add_peer(peer)
self.routing_table.join_buckets()
return result
else:
# We can't split the k-bucket
#
# The 13 page kademlia paper specifies that the least recently contacted node in the bucket
# shall be pinged. If it fails to reply it is replaced with the new contact. If the ping is successful
# the new contact is ignored and not added to the bucket (sections 2.2 and 2.4).
#
# A reasonable extension to this is BEP 0005, which extends the above:
#
# Not all nodes that we learn about are equal. Some are "good" and some are not.
# Many nodes using the DHT are able to send queries and receive responses,
# but are not able to respond to queries from other nodes. It is important that
# each node's routing table must contain only known good nodes. A good node is
# a node has responded to one of our queries within the last 15 minutes. A node
# is also good if it has ever responded to one of our queries and has sent us a
# query within the last 15 minutes. After 15 minutes of inactivity, a node becomes
# questionable. Nodes become bad when they fail to respond to multiple queries
# in a row. Nodes that we know are good are given priority over nodes with unknown status.
#
# When there are bad or questionable nodes in the bucket, the least recent is selected for
# potential replacement (BEP 0005). When all nodes in the bucket are fresh, the head (least recent)
# contact is selected as described in section 2.2 of the kademlia paper. In both cases the new contact
# is ignored if the pinged node replies.
not_good_contacts = self.routing_table.buckets[bucket_index].get_bad_or_unknown_peers()
not_recently_replied = []
for my_peer in not_good_contacts:
last_replied = self.peer_manager.get_last_replied(my_peer.address, my_peer.udp_port)
if not last_replied or last_replied + 60 < self.loop.time():
not_recently_replied.append(my_peer)
if not_recently_replied:
to_replace = not_recently_replied[0]
else:
to_replace = self.routing_table.buckets[bucket_index].peers[0]
last_replied = self.peer_manager.get_last_replied(to_replace.address, to_replace.udp_port)
if last_replied and last_replied + 60 > self.loop.time():
return False
log.debug("pinging %s:%s", to_replace.address, to_replace.udp_port)
try:
to_replace_rpc = self.get_rpc_peer(to_replace)
await to_replace_rpc.ping()
return False
except asyncio.TimeoutError:
log.debug("Replacing dead contact in bucket %i: %s:%i with %s:%i ", bucket_index,
to_replace.address, to_replace.udp_port, peer.address, peer.udp_port)
if to_replace in self.routing_table.buckets[bucket_index]:
self.routing_table.buckets[bucket_index].remove_peer(to_replace)
return await self._add_peer(peer)
def add_peer(self, peer: 'KademliaPeer'): def add_peer(self, peer: 'KademliaPeer'):
if peer.node_id == self.node_id: if peer.node_id == self.node_id:
@ -439,7 +377,6 @@ class KademliaProtocol(DatagramProtocol):
async with self._split_lock: async with self._split_lock:
peer = self._to_remove.pop() peer = self._to_remove.pop()
self.routing_table.remove_peer(peer) self.routing_table.remove_peer(peer)
self.routing_table.join_buckets()
while self._to_add: while self._to_add:
async with self._split_lock: async with self._split_lock:
await self._add_peer(self._to_add.pop()) await self._add_peer(self._to_add.pop())

View file

@ -248,15 +248,10 @@ class TreeRoutingTable:
bucket_index = self.kbucket_index(peer.node_id) bucket_index = self.kbucket_index(peer.node_id)
try: try:
self.buckets[bucket_index].remove_peer(peer) self.buckets[bucket_index].remove_peer(peer)
self._join_buckets()
except ValueError: except ValueError:
return return
def touch_kbucket(self, key: bytes) -> None:
self.touch_kbucket_by_index(self.kbucket_index(key))
def touch_kbucket_by_index(self, bucket_index: int):
self.buckets[bucket_index].last_accessed = int(self._loop.time())
def kbucket_index(self, key: bytes) -> int: def kbucket_index(self, key: bytes) -> int:
i = 0 i = 0
for bucket in self.buckets: for bucket in self.buckets:
@ -303,7 +298,7 @@ class TreeRoutingTable:
old_bucket.remove_peer(contact) old_bucket.remove_peer(contact)
self.bucket_in_routing_table_metric.labels("global").set(len(self.buckets)) self.bucket_in_routing_table_metric.labels("global").set(len(self.buckets))
def join_buckets(self): def _join_buckets(self):
if len(self.buckets) == 1: if len(self.buckets) == 1:
return return
to_pop = [i for i, bucket in enumerate(self.buckets) if len(bucket) == 0] to_pop = [i for i, bucket in enumerate(self.buckets) if len(bucket) == 0]
@ -326,14 +321,7 @@ class TreeRoutingTable:
self.buckets[bucket_index_to_pop + 1].range_min = bucket.range_min self.buckets[bucket_index_to_pop + 1].range_min = bucket.range_min
self.buckets.remove(bucket) self.buckets.remove(bucket)
self.bucket_in_routing_table_metric.labels("global").set(len(self.buckets)) self.bucket_in_routing_table_metric.labels("global").set(len(self.buckets))
return self.join_buckets() return self._join_buckets()
def contact_in_routing_table(self, address_tuple: typing.Tuple[str, int]) -> bool:
for bucket in self.buckets:
for contact in bucket.get_peers(sort_distance_to=False):
if address_tuple[0] == contact.address and address_tuple[1] == contact.udp_port:
return True
return False
def buckets_with_contacts(self) -> int: def buckets_with_contacts(self) -> int:
count = 0 count = 0
@ -341,3 +329,70 @@ class TreeRoutingTable:
if len(bucket) > 0: if len(bucket) > 0:
count += 1 count += 1
return count return count
async def add_peer(self, peer: 'KademliaPeer', probe: typing.Callable[['KademliaPeer'], typing.Awaitable]):
if not peer.node_id:
log.warning("Tried adding a peer with no node id!")
return False
for my_peer in self.get_peers():
if (my_peer.address, my_peer.udp_port) == (peer.address, peer.udp_port) and my_peer.node_id != peer.node_id:
self.remove_peer(my_peer)
self._join_buckets()
bucket_index = self.kbucket_index(peer.node_id)
if self.buckets[bucket_index].add_peer(peer):
return True
# The bucket is full; see if it can be split (by checking if its range includes the host node's node_id)
if self.should_split(bucket_index, peer.node_id):
self.split_bucket(bucket_index)
# Retry the insertion attempt
result = await self.add_peer(peer, probe)
self._join_buckets()
return result
else:
# We can't split the k-bucket
#
# The 13 page kademlia paper specifies that the least recently contacted node in the bucket
# shall be pinged. If it fails to reply it is replaced with the new contact. If the ping is successful
# the new contact is ignored and not added to the bucket (sections 2.2 and 2.4).
#
# A reasonable extension to this is BEP 0005, which extends the above:
#
# Not all nodes that we learn about are equal. Some are "good" and some are not.
# Many nodes using the DHT are able to send queries and receive responses,
# but are not able to respond to queries from other nodes. It is important that
# each node's routing table must contain only known good nodes. A good node is
# a node has responded to one of our queries within the last 15 minutes. A node
# is also good if it has ever responded to one of our queries and has sent us a
# query within the last 15 minutes. After 15 minutes of inactivity, a node becomes
# questionable. Nodes become bad when they fail to respond to multiple queries
# in a row. Nodes that we know are good are given priority over nodes with unknown status.
#
# When there are bad or questionable nodes in the bucket, the least recent is selected for
# potential replacement (BEP 0005). When all nodes in the bucket are fresh, the head (least recent)
# contact is selected as described in section 2.2 of the kademlia paper. In both cases the new contact
# is ignored if the pinged node replies.
not_good_contacts = self.buckets[bucket_index].get_bad_or_unknown_peers()
not_recently_replied = []
for my_peer in not_good_contacts:
last_replied = self._peer_manager.get_last_replied(my_peer.address, my_peer.udp_port)
if not last_replied or last_replied + 60 < self._loop.time():
not_recently_replied.append(my_peer)
if not_recently_replied:
to_replace = not_recently_replied[0]
else:
to_replace = self.buckets[bucket_index].peers[0]
last_replied = self._peer_manager.get_last_replied(to_replace.address, to_replace.udp_port)
if last_replied and last_replied + 60 > self._loop.time():
return False
log.debug("pinging %s:%s", to_replace.address, to_replace.udp_port)
try:
await probe(to_replace)
return False
except asyncio.TimeoutError:
log.debug("Replacing dead contact in bucket %i: %s:%i with %s:%i ", bucket_index,
to_replace.address, to_replace.udp_port, peer.address, peer.udp_port)
if to_replace in self.buckets[bucket_index]:
self.buckets[bucket_index].remove_peer(to_replace)
return await self.add_peer(peer, probe)