Replace kad-dht with bmuller/kademlia
This commit is contained in:
Stuckinaboot
parent
99d37c8221
commit
63e0f0210c
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@ -1,4 +0,0 @@
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"""
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A Kademlia DHT implemention on py-libp2p
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"""
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__version__ = "0.0"
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5
kademlia/__init__.py
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5
kademlia/__init__.py
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"""
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Kademlia is a Python implementation of the Kademlia protocol which
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utilizes the asyncio library.
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"""
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__version__ = "1.1"
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181
kademlia/crawling.py
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181
kademlia/crawling.py
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from collections import Counter
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import logging
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from kademlia.node import Node, NodeHeap
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from kademlia.utils import gather_dict
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log = logging.getLogger(__name__)
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class SpiderCrawl(object):
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"""
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Crawl the network and look for given 160-bit keys.
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"""
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def __init__(self, protocol, node, peers, ksize, alpha):
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"""
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Create a new C{SpiderCrawl}er.
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Args:
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protocol: A :class:`~kademlia.protocol.KademliaProtocol` instance.
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node: A :class:`~kademlia.node.Node` representing the key we're
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looking for
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peers: A list of :class:`~kademlia.node.Node` instances that
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provide the entry point for the network
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ksize: The value for k based on the paper
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alpha: The value for alpha based on the paper
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"""
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self.protocol = protocol
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self.ksize = ksize
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self.alpha = alpha
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self.node = node
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self.nearest = NodeHeap(self.node, self.ksize)
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self.lastIDsCrawled = []
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log.info("creating spider with peers: %s", peers)
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self.nearest.push(peers)
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async def _find(self, rpcmethod):
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"""
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Get either a value or list of nodes.
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Args:
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rpcmethod: The protocol's callfindValue or callFindNode.
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The process:
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1. calls find_* to current ALPHA nearest not already queried nodes,
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adding results to current nearest list of k nodes.
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2. current nearest list needs to keep track of who has been queried
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already sort by nearest, keep KSIZE
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3. if list is same as last time, next call should be to everyone not
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yet queried
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4. repeat, unless nearest list has all been queried, then ur done
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"""
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log.info("crawling network with nearest: %s", str(tuple(self.nearest)))
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count = self.alpha
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if self.nearest.getIDs() == self.lastIDsCrawled:
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count = len(self.nearest)
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self.lastIDsCrawled = self.nearest.getIDs()
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ds = {}
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for peer in self.nearest.getUncontacted()[:count]:
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ds[peer.id] = rpcmethod(peer, self.node)
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self.nearest.markContacted(peer)
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found = await gather_dict(ds)
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return await self._nodesFound(found)
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async def _nodesFound(self, responses):
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raise NotImplementedError
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class ValueSpiderCrawl(SpiderCrawl):
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def __init__(self, protocol, node, peers, ksize, alpha):
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SpiderCrawl.__init__(self, protocol, node, peers, ksize, alpha)
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# keep track of the single nearest node without value - per
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# section 2.3 so we can set the key there if found
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self.nearestWithoutValue = NodeHeap(self.node, 1)
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async def find(self):
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"""
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Find either the closest nodes or the value requested.
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"""
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return await self._find(self.protocol.callFindValue)
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async def _nodesFound(self, responses):
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"""
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Handle the result of an iteration in _find.
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"""
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toremove = []
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foundValues = []
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for peerid, response in responses.items():
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response = RPCFindResponse(response)
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if not response.happened():
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toremove.append(peerid)
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elif response.hasValue():
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foundValues.append(response.getValue())
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else:
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peer = self.nearest.getNodeById(peerid)
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self.nearestWithoutValue.push(peer)
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self.nearest.push(response.getNodeList())
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self.nearest.remove(toremove)
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if len(foundValues) > 0:
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return await self._handleFoundValues(foundValues)
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if self.nearest.allBeenContacted():
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# not found!
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return None
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return await self.find()
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async def _handleFoundValues(self, values):
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"""
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We got some values! Exciting. But let's make sure
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they're all the same or freak out a little bit. Also,
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make sure we tell the nearest node that *didn't* have
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the value to store it.
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"""
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valueCounts = Counter(values)
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if len(valueCounts) != 1:
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log.warning("Got multiple values for key %i: %s",
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self.node.long_id, str(values))
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value = valueCounts.most_common(1)[0][0]
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peerToSaveTo = self.nearestWithoutValue.popleft()
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if peerToSaveTo is not None:
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await self.protocol.callStore(peerToSaveTo, self.node.id, value)
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return value
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class NodeSpiderCrawl(SpiderCrawl):
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async def find(self):
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"""
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Find the closest nodes.
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"""
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return await self._find(self.protocol.callFindNode)
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async def _nodesFound(self, responses):
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"""
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Handle the result of an iteration in _find.
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"""
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toremove = []
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for peerid, response in responses.items():
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response = RPCFindResponse(response)
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if not response.happened():
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toremove.append(peerid)
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else:
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self.nearest.push(response.getNodeList())
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self.nearest.remove(toremove)
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if self.nearest.allBeenContacted():
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return list(self.nearest)
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return await self.find()
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class RPCFindResponse(object):
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def __init__(self, response):
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"""
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A wrapper for the result of a RPC find.
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Args:
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response: This will be a tuple of (<response received>, <value>)
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where <value> will be a list of tuples if not found or
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a dictionary of {'value': v} where v is the value desired
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"""
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self.response = response
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def happened(self):
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"""
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Did the other host actually respond?
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"""
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return self.response[0]
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def hasValue(self):
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return isinstance(self.response[1], dict)
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def getValue(self):
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return self.response[1]['value']
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def getNodeList(self):
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"""
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Get the node list in the response. If there's no value, this should
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be set.
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"""
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nodelist = self.response[1] or []
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return [Node(*nodeple) for nodeple in nodelist]
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258
kademlia/network.py
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258
kademlia/network.py
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"""
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Package for interacting on the network at a high level.
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"""
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import random
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import pickle
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import asyncio
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import logging
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from kademlia.protocol import KademliaProtocol
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from kademlia.utils import digest
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from kademlia.storage import ForgetfulStorage
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from kademlia.node import Node
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from kademlia.crawling import ValueSpiderCrawl
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from kademlia.crawling import NodeSpiderCrawl
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log = logging.getLogger(__name__)
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class Server(object):
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"""
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High level view of a node instance. This is the object that should be
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created to start listening as an active node on the network.
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"""
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protocol_class = KademliaProtocol
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def __init__(self, ksize=20, alpha=3, node_id=None, storage=None):
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"""
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Create a server instance. This will start listening on the given port.
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Args:
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ksize (int): The k parameter from the paper
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alpha (int): The alpha parameter from the paper
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node_id: The id for this node on the network.
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storage: An instance that implements
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:interface:`~kademlia.storage.IStorage`
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"""
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self.ksize = ksize
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self.alpha = alpha
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self.storage = storage or ForgetfulStorage()
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self.node = Node(node_id or digest(random.getrandbits(255)))
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self.transport = None
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self.protocol = None
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self.refresh_loop = None
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self.save_state_loop = None
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def stop(self):
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if self.transport is not None:
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self.transport.close()
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if self.refresh_loop:
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self.refresh_loop.cancel()
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if self.save_state_loop:
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self.save_state_loop.cancel()
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def _create_protocol(self):
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return self.protocol_class(self.node, self.storage, self.ksize)
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def listen(self, port, interface='0.0.0.0'):
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"""
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Start listening on the given port.
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Provide interface="::" to accept ipv6 address
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"""
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loop = asyncio.get_event_loop()
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listen = loop.create_datagram_endpoint(self._create_protocol,
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local_addr=(interface, port))
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log.info("Node %i listening on %s:%i",
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self.node.long_id, interface, port)
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self.transport, self.protocol = loop.run_until_complete(listen)
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# finally, schedule refreshing table
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self.refresh_table()
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def refresh_table(self):
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log.debug("Refreshing routing table")
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asyncio.ensure_future(self._refresh_table())
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loop = asyncio.get_event_loop()
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self.refresh_loop = loop.call_later(3600, self.refresh_table)
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async def _refresh_table(self):
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"""
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Refresh buckets that haven't had any lookups in the last hour
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(per section 2.3 of the paper).
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"""
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ds = []
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for node_id in self.protocol.getRefreshIDs():
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node = Node(node_id)
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nearest = self.protocol.router.findNeighbors(node, self.alpha)
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spider = NodeSpiderCrawl(self.protocol, node, nearest,
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self.ksize, self.alpha)
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ds.append(spider.find())
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# do our crawling
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await asyncio.gather(*ds)
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# now republish keys older than one hour
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for dkey, value in self.storage.iteritemsOlderThan(3600):
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await self.set_digest(dkey, value)
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def bootstrappableNeighbors(self):
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"""
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Get a :class:`list` of (ip, port) :class:`tuple` pairs suitable for
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use as an argument to the bootstrap method.
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The server should have been bootstrapped
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already - this is just a utility for getting some neighbors and then
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storing them if this server is going down for a while. When it comes
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back up, the list of nodes can be used to bootstrap.
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"""
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neighbors = self.protocol.router.findNeighbors(self.node)
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return [tuple(n)[-2:] for n in neighbors]
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async def bootstrap(self, addrs):
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"""
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Bootstrap the server by connecting to other known nodes in the network.
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Args:
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addrs: A `list` of (ip, port) `tuple` pairs. Note that only IP
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addresses are acceptable - hostnames will cause an error.
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"""
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log.debug("Attempting to bootstrap node with %i initial contacts",
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len(addrs))
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cos = list(map(self.bootstrap_node, addrs))
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gathered = await asyncio.gather(*cos)
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nodes = [node for node in gathered if node is not None]
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spider = NodeSpiderCrawl(self.protocol, self.node, nodes,
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self.ksize, self.alpha)
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return await spider.find()
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async def bootstrap_node(self, addr):
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result = await self.protocol.ping(addr, self.node.id)
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return Node(result[1], addr[0], addr[1]) if result[0] else None
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async def get(self, key):
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"""
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Get a key if the network has it.
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Returns:
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:class:`None` if not found, the value otherwise.
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"""
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log.info("Looking up key %s", key)
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dkey = digest(key)
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# if this node has it, return it
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if self.storage.get(dkey) is not None:
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return self.storage.get(dkey)
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node = Node(dkey)
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nearest = self.protocol.router.findNeighbors(node)
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if len(nearest) == 0:
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log.warning("There are no known neighbors to get key %s", key)
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return None
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spider = ValueSpiderCrawl(self.protocol, node, nearest,
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self.ksize, self.alpha)
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return await spider.find()
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async def set(self, key, value):
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"""
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Set the given string key to the given value in the network.
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"""
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if not check_dht_value_type(value):
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raise TypeError(
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"Value must be of type int, float, bool, str, or bytes"
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)
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log.info("setting '%s' = '%s' on network", key, value)
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dkey = digest(key)
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return await self.set_digest(dkey, value)
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async def set_digest(self, dkey, value):
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"""
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Set the given SHA1 digest key (bytes) to the given value in the
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network.
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"""
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node = Node(dkey)
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nearest = self.protocol.router.findNeighbors(node)
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if len(nearest) == 0:
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log.warning("There are no known neighbors to set key %s",
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dkey.hex())
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return False
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spider = NodeSpiderCrawl(self.protocol, node, nearest,
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self.ksize, self.alpha)
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nodes = await spider.find()
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log.info("setting '%s' on %s", dkey.hex(), list(map(str, nodes)))
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# if this node is close too, then store here as well
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biggest = max([n.distanceTo(node) for n in nodes])
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if self.node.distanceTo(node) < biggest:
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self.storage[dkey] = value
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ds = [self.protocol.callStore(n, dkey, value) for n in nodes]
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# return true only if at least one store call succeeded
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return any(await asyncio.gather(*ds))
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def saveState(self, fname):
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"""
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Save the state of this node (the alpha/ksize/id/immediate neighbors)
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to a cache file with the given fname.
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"""
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log.info("Saving state to %s", fname)
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data = {
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'ksize': self.ksize,
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'alpha': self.alpha,
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'id': self.node.id,
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'neighbors': self.bootstrappableNeighbors()
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}
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if len(data['neighbors']) == 0:
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log.warning("No known neighbors, so not writing to cache.")
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return
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with open(fname, 'wb') as f:
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pickle.dump(data, f)
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@classmethod
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def loadState(self, fname):
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"""
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Load the state of this node (the alpha/ksize/id/immediate neighbors)
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from a cache file with the given fname.
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"""
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log.info("Loading state from %s", fname)
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with open(fname, 'rb') as f:
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data = pickle.load(f)
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s = Server(data['ksize'], data['alpha'], data['id'])
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if len(data['neighbors']) > 0:
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s.bootstrap(data['neighbors'])
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return s
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def saveStateRegularly(self, fname, frequency=600):
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"""
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Save the state of node with a given regularity to the given
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filename.
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Args:
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fname: File name to save retularly to
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frequency: Frequency in seconds that the state should be saved.
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By default, 10 minutes.
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"""
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self.saveState(fname)
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loop = asyncio.get_event_loop()
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self.save_state_loop = loop.call_later(frequency,
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self.saveStateRegularly,
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fname,
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frequency)
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def check_dht_value_type(value):
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"""
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Checks to see if the type of the value is a valid type for
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placing in the dht.
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"""
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typeset = set(
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[
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int,
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float,
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bool,
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str,
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bytes,
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]
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)
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return type(value) in typeset
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115
kademlia/node.py
Normal file
115
kademlia/node.py
Normal file
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from operator import itemgetter
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import heapq
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class Node:
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def __init__(self, node_id, ip=None, port=None):
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self.id = node_id
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self.ip = ip
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self.port = port
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self.long_id = int(node_id.hex(), 16)
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def sameHomeAs(self, node):
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return self.ip == node.ip and self.port == node.port
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def distanceTo(self, node):
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"""
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Get the distance between this node and another.
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"""
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return self.long_id ^ node.long_id
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def __iter__(self):
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"""
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Enables use of Node as a tuple - i.e., tuple(node) works.
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"""
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return iter([self.id, self.ip, self.port])
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def __repr__(self):
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return repr([self.long_id, self.ip, self.port])
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def __str__(self):
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return "%s:%s" % (self.ip, str(self.port))
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class NodeHeap(object):
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"""
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A heap of nodes ordered by distance to a given node.
|
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"""
|
||||
def __init__(self, node, maxsize):
|
||||
"""
|
||||
Constructor.
|
||||
|
||||
@param node: The node to measure all distnaces from.
|
||||
@param maxsize: The maximum size that this heap can grow to.
|
||||
"""
|
||||
self.node = node
|
||||
self.heap = []
|
||||
self.contacted = set()
|
||||
self.maxsize = maxsize
|
||||
|
||||
def remove(self, peerIDs):
|
||||
"""
|
||||
Remove a list of peer ids from this heap. Note that while this
|
||||
heap retains a constant visible size (based on the iterator), it's
|
||||
actual size may be quite a bit larger than what's exposed. Therefore,
|
||||
removal of nodes may not change the visible size as previously added
|
||||
nodes suddenly become visible.
|
||||
"""
|
||||
peerIDs = set(peerIDs)
|
||||
if len(peerIDs) == 0:
|
||||
return
|
||||
nheap = []
|
||||
for distance, node in self.heap:
|
||||
if node.id not in peerIDs:
|
||||
heapq.heappush(nheap, (distance, node))
|
||||
self.heap = nheap
|
||||
|
||||
def getNodeById(self, node_id):
|
||||
for _, node in self.heap:
|
||||
if node.id == node_id:
|
||||
return node
|
||||
return None
|
||||
|
||||
def allBeenContacted(self):
|
||||
return len(self.getUncontacted()) == 0
|
||||
|
||||
def getIDs(self):
|
||||
return [n.id for n in self]
|
||||
|
||||
def markContacted(self, node):
|
||||
self.contacted.add(node.id)
|
||||
|
||||
def popleft(self):
|
||||
if len(self) > 0:
|
||||
return heapq.heappop(self.heap)[1]
|
||||
return None
|
||||
|
||||
def push(self, nodes):
|
||||
"""
|
||||
Push nodes onto heap.
|
||||
|
||||
@param nodes: This can be a single item or a C{list}.
|
||||
"""
|
||||
if not isinstance(nodes, list):
|
||||
nodes = [nodes]
|
||||
|
||||
for node in nodes:
|
||||
if node not in self:
|
||||
distance = self.node.distanceTo(node)
|
||||
heapq.heappush(self.heap, (distance, node))
|
||||
|
||||
def __len__(self):
|
||||
return min(len(self.heap), self.maxsize)
|
||||
|
||||
def __iter__(self):
|
||||
nodes = heapq.nsmallest(self.maxsize, self.heap)
|
||||
return iter(map(itemgetter(1), nodes))
|
||||
|
||||
def __contains__(self, node):
|
||||
for _, n in self.heap:
|
||||
if node.id == n.id:
|
||||
return True
|
||||
return False
|
||||
|
||||
def getUncontacted(self):
|
||||
return [n for n in self if n.id not in self.contacted]
|
||||
128
kademlia/protocol.py
Normal file
128
kademlia/protocol.py
Normal file
|
|
@ -0,0 +1,128 @@
|
|||
import random
|
||||
import asyncio
|
||||
import logging
|
||||
|
||||
from rpcudp.protocol import RPCProtocol
|
||||
|
||||
from kademlia.node import Node
|
||||
from kademlia.routing import RoutingTable
|
||||
from kademlia.utils import digest
|
||||
|
||||
log = logging.getLogger(__name__)
|
||||
|
||||
|
||||
class KademliaProtocol(RPCProtocol):
|
||||
def __init__(self, sourceNode, storage, ksize):
|
||||
RPCProtocol.__init__(self)
|
||||
self.router = RoutingTable(self, ksize, sourceNode)
|
||||
self.storage = storage
|
||||
self.sourceNode = sourceNode
|
||||
|
||||
def getRefreshIDs(self):
|
||||
"""
|
||||
Get ids to search for to keep old buckets up to date.
|
||||
"""
|
||||
ids = []
|
||||
for bucket in self.router.getLonelyBuckets():
|
||||
rid = random.randint(*bucket.range).to_bytes(20, byteorder='big')
|
||||
ids.append(rid)
|
||||
return ids
|
||||
|
||||
def rpc_stun(self, sender):
|
||||
return sender
|
||||
|
||||
def rpc_ping(self, sender, nodeid):
|
||||
source = Node(nodeid, sender[0], sender[1])
|
||||
self.welcomeIfNewNode(source)
|
||||
return self.sourceNode.id
|
||||
|
||||
def rpc_store(self, sender, nodeid, key, value):
|
||||
source = Node(nodeid, sender[0], sender[1])
|
||||
self.welcomeIfNewNode(source)
|
||||
log.debug("got a store request from %s, storing '%s'='%s'",
|
||||
sender, key.hex(), value)
|
||||
self.storage[key] = value
|
||||
return True
|
||||
|
||||
def rpc_find_node(self, sender, nodeid, key):
|
||||
log.info("finding neighbors of %i in local table",
|
||||
int(nodeid.hex(), 16))
|
||||
source = Node(nodeid, sender[0], sender[1])
|
||||
self.welcomeIfNewNode(source)
|
||||
node = Node(key)
|
||||
neighbors = self.router.findNeighbors(node, exclude=source)
|
||||
return list(map(tuple, neighbors))
|
||||
|
||||
def rpc_find_value(self, sender, nodeid, key):
|
||||
source = Node(nodeid, sender[0], sender[1])
|
||||
self.welcomeIfNewNode(source)
|
||||
value = self.storage.get(key, None)
|
||||
if value is None:
|
||||
return self.rpc_find_node(sender, nodeid, key)
|
||||
return {'value': value}
|
||||
|
||||
async def callFindNode(self, nodeToAsk, nodeToFind):
|
||||
address = (nodeToAsk.ip, nodeToAsk.port)
|
||||
result = await self.find_node(address, self.sourceNode.id,
|
||||
nodeToFind.id)
|
||||
return self.handleCallResponse(result, nodeToAsk)
|
||||
|
||||
async def callFindValue(self, nodeToAsk, nodeToFind):
|
||||
address = (nodeToAsk.ip, nodeToAsk.port)
|
||||
result = await self.find_value(address, self.sourceNode.id,
|
||||
nodeToFind.id)
|
||||
return self.handleCallResponse(result, nodeToAsk)
|
||||
|
||||
async def callPing(self, nodeToAsk):
|
||||
address = (nodeToAsk.ip, nodeToAsk.port)
|
||||
result = await self.ping(address, self.sourceNode.id)
|
||||
return self.handleCallResponse(result, nodeToAsk)
|
||||
|
||||
async def callStore(self, nodeToAsk, key, value):
|
||||
address = (nodeToAsk.ip, nodeToAsk.port)
|
||||
result = await self.store(address, self.sourceNode.id, key, value)
|
||||
return self.handleCallResponse(result, nodeToAsk)
|
||||
|
||||
def welcomeIfNewNode(self, node):
|
||||
"""
|
||||
Given a new node, send it all the keys/values it should be storing,
|
||||
then add it to the routing table.
|
||||
|
||||
@param node: A new node that just joined (or that we just found out
|
||||
about).
|
||||
|
||||
Process:
|
||||
For each key in storage, get k closest nodes. If newnode is closer
|
||||
than the furtherst in that list, and the node for this server
|
||||
is closer than the closest in that list, then store the key/value
|
||||
on the new node (per section 2.5 of the paper)
|
||||
"""
|
||||
if not self.router.isNewNode(node):
|
||||
return
|
||||
|
||||
log.info("never seen %s before, adding to router", node)
|
||||
for key, value in self.storage.items():
|
||||
keynode = Node(digest(key))
|
||||
neighbors = self.router.findNeighbors(keynode)
|
||||
if len(neighbors) > 0:
|
||||
last = neighbors[-1].distanceTo(keynode)
|
||||
newNodeClose = node.distanceTo(keynode) < last
|
||||
first = neighbors[0].distanceTo(keynode)
|
||||
thisNodeClosest = self.sourceNode.distanceTo(keynode) < first
|
||||
if len(neighbors) == 0 or (newNodeClose and thisNodeClosest):
|
||||
asyncio.ensure_future(self.callStore(node, key, value))
|
||||
self.router.addContact(node)
|
||||
|
||||
def handleCallResponse(self, result, node):
|
||||
"""
|
||||
If we get a response, add the node to the routing table. If
|
||||
we get no response, make sure it's removed from the routing table.
|
||||
"""
|
||||
if not result[0]:
|
||||
log.warning("no response from %s, removing from router", node)
|
||||
self.router.removeContact(node)
|
||||
return result
|
||||
|
||||
log.info("got successful response from %s", node)
|
||||
self.welcomeIfNewNode(node)
|
||||
return result
|
||||
184
kademlia/routing.py
Normal file
184
kademlia/routing.py
Normal file
|
|
@ -0,0 +1,184 @@
|
|||
import heapq
|
||||
import time
|
||||
import operator
|
||||
import asyncio
|
||||
|
||||
from collections import OrderedDict
|
||||
from kademlia.utils import OrderedSet, sharedPrefix, bytesToBitString
|
||||
|
||||
|
||||
class KBucket(object):
|
||||
def __init__(self, rangeLower, rangeUpper, ksize):
|
||||
self.range = (rangeLower, rangeUpper)
|
||||
self.nodes = OrderedDict()
|
||||
self.replacementNodes = OrderedSet()
|
||||
self.touchLastUpdated()
|
||||
self.ksize = ksize
|
||||
|
||||
def touchLastUpdated(self):
|
||||
self.lastUpdated = time.monotonic()
|
||||
|
||||
def getNodes(self):
|
||||
return list(self.nodes.values())
|
||||
|
||||
def split(self):
|
||||
midpoint = (self.range[0] + self.range[1]) / 2
|
||||
one = KBucket(self.range[0], midpoint, self.ksize)
|
||||
two = KBucket(midpoint + 1, self.range[1], self.ksize)
|
||||
for node in self.nodes.values():
|
||||
bucket = one if node.long_id <= midpoint else two
|
||||
bucket.nodes[node.id] = node
|
||||
return (one, two)
|
||||
|
||||
def removeNode(self, node):
|
||||
if node.id not in self.nodes:
|
||||
return
|
||||
|
||||
# delete node, and see if we can add a replacement
|
||||
del self.nodes[node.id]
|
||||
if len(self.replacementNodes) > 0:
|
||||
newnode = self.replacementNodes.pop()
|
||||
self.nodes[newnode.id] = newnode
|
||||
|
||||
def hasInRange(self, node):
|
||||
return self.range[0] <= node.long_id <= self.range[1]
|
||||
|
||||
def isNewNode(self, node):
|
||||
return node.id not in self.nodes
|
||||
|
||||
def addNode(self, node):
|
||||
"""
|
||||
Add a C{Node} to the C{KBucket}. Return True if successful,
|
||||
False if the bucket is full.
|
||||
|
||||
If the bucket is full, keep track of node in a replacement list,
|
||||
per section 4.1 of the paper.
|
||||
"""
|
||||
if node.id in self.nodes:
|
||||
del self.nodes[node.id]
|
||||
self.nodes[node.id] = node
|
||||
elif len(self) < self.ksize:
|
||||
self.nodes[node.id] = node
|
||||
else:
|
||||
self.replacementNodes.push(node)
|
||||
return False
|
||||
return True
|
||||
|
||||
def depth(self):
|
||||
vals = self.nodes.values()
|
||||
sp = sharedPrefix([bytesToBitString(n.id) for n in vals])
|
||||
return len(sp)
|
||||
|
||||
def head(self):
|
||||
return list(self.nodes.values())[0]
|
||||
|
||||
def __getitem__(self, node_id):
|
||||
return self.nodes.get(node_id, None)
|
||||
|
||||
def __len__(self):
|
||||
return len(self.nodes)
|
||||
|
||||
|
||||
class TableTraverser(object):
|
||||
def __init__(self, table, startNode):
|
||||
index = table.getBucketFor(startNode)
|
||||
table.buckets[index].touchLastUpdated()
|
||||
self.currentNodes = table.buckets[index].getNodes()
|
||||
self.leftBuckets = table.buckets[:index]
|
||||
self.rightBuckets = table.buckets[(index + 1):]
|
||||
self.left = True
|
||||
|
||||
def __iter__(self):
|
||||
return self
|
||||
|
||||
def __next__(self):
|
||||
"""
|
||||
Pop an item from the left subtree, then right, then left, etc.
|
||||
"""
|
||||
if len(self.currentNodes) > 0:
|
||||
return self.currentNodes.pop()
|
||||
|
||||
if self.left and len(self.leftBuckets) > 0:
|
||||
self.currentNodes = self.leftBuckets.pop().getNodes()
|
||||
self.left = False
|
||||
return next(self)
|
||||
|
||||
if len(self.rightBuckets) > 0:
|
||||
self.currentNodes = self.rightBuckets.pop(0).getNodes()
|
||||
self.left = True
|
||||
return next(self)
|
||||
|
||||
raise StopIteration
|
||||
|
||||
|
||||
class RoutingTable(object):
|
||||
def __init__(self, protocol, ksize, node):
|
||||
"""
|
||||
@param node: The node that represents this server. It won't
|
||||
be added to the routing table, but will be needed later to
|
||||
determine which buckets to split or not.
|
||||
"""
|
||||
self.node = node
|
||||
self.protocol = protocol
|
||||
self.ksize = ksize
|
||||
self.flush()
|
||||
|
||||
def flush(self):
|
||||
self.buckets = [KBucket(0, 2 ** 160, self.ksize)]
|
||||
|
||||
def splitBucket(self, index):
|
||||
one, two = self.buckets[index].split()
|
||||
self.buckets[index] = one
|
||||
self.buckets.insert(index + 1, two)
|
||||
|
||||
def getLonelyBuckets(self):
|
||||
"""
|
||||
Get all of the buckets that haven't been updated in over
|
||||
an hour.
|
||||
"""
|
||||
hrago = time.monotonic() - 3600
|
||||
return [b for b in self.buckets if b.lastUpdated < hrago]
|
||||
|
||||
def removeContact(self, node):
|
||||
index = self.getBucketFor(node)
|
||||
self.buckets[index].removeNode(node)
|
||||
|
||||
def isNewNode(self, node):
|
||||
index = self.getBucketFor(node)
|
||||
return self.buckets[index].isNewNode(node)
|
||||
|
||||
def addContact(self, node):
|
||||
index = self.getBucketFor(node)
|
||||
bucket = self.buckets[index]
|
||||
|
||||
# this will succeed unless the bucket is full
|
||||
if bucket.addNode(node):
|
||||
return
|
||||
|
||||
# Per section 4.2 of paper, split if the bucket has the node
|
||||
# in its range or if the depth is not congruent to 0 mod 5
|
||||
if bucket.hasInRange(self.node) or bucket.depth() % 5 != 0:
|
||||
self.splitBucket(index)
|
||||
self.addContact(node)
|
||||
else:
|
||||
asyncio.ensure_future(self.protocol.callPing(bucket.head()))
|
||||
|
||||
def getBucketFor(self, node):
|
||||
"""
|
||||
Get the index of the bucket that the given node would fall into.
|
||||
"""
|
||||
for index, bucket in enumerate(self.buckets):
|
||||
if node.long_id < bucket.range[1]:
|
||||
return index
|
||||
|
||||
def findNeighbors(self, node, k=None, exclude=None):
|
||||
k = k or self.ksize
|
||||
nodes = []
|
||||
for neighbor in TableTraverser(self, node):
|
||||
notexcluded = exclude is None or not neighbor.sameHomeAs(exclude)
|
||||
if neighbor.id != node.id and notexcluded:
|
||||
heapq.heappush(nodes, (node.distanceTo(neighbor), neighbor))
|
||||
if len(nodes) == k:
|
||||
break
|
||||
|
||||
return list(map(operator.itemgetter(1), heapq.nsmallest(k, nodes)))
|
||||
97
kademlia/storage.py
Normal file
97
kademlia/storage.py
Normal file
|
|
@ -0,0 +1,97 @@
|
|||
import time
|
||||
from itertools import takewhile
|
||||
import operator
|
||||
from collections import OrderedDict
|
||||
|
||||
|
||||
class IStorage:
|
||||
"""
|
||||
Local storage for this node.
|
||||
IStorage implementations of get must return the same type as put in by set
|
||||
"""
|
||||
|
||||
def __setitem__(self, key, value):
|
||||
"""
|
||||
Set a key to the given value.
|
||||
"""
|
||||
raise NotImplementedError
|
||||
|
||||
def __getitem__(self, key):
|
||||
"""
|
||||
Get the given key. If item doesn't exist, raises C{KeyError}
|
||||
"""
|
||||
raise NotImplementedError
|
||||
|
||||
def get(self, key, default=None):
|
||||
"""
|
||||
Get given key. If not found, return default.
|
||||
"""
|
||||
raise NotImplementedError
|
||||
|
||||
def iteritemsOlderThan(self, secondsOld):
|
||||
"""
|
||||
Return the an iterator over (key, value) tuples for items older
|
||||
than the given secondsOld.
|
||||
"""
|
||||
raise NotImplementedError
|
||||
|
||||
def __iter__(self):
|
||||
"""
|
||||
Get the iterator for this storage, should yield tuple of (key, value)
|
||||
"""
|
||||
raise NotImplementedError
|
||||
|
||||
|
||||
class ForgetfulStorage(IStorage):
|
||||
def __init__(self, ttl=604800):
|
||||
"""
|
||||
By default, max age is a week.
|
||||
"""
|
||||
self.data = OrderedDict()
|
||||
self.ttl = ttl
|
||||
|
||||
def __setitem__(self, key, value):
|
||||
if key in self.data:
|
||||
del self.data[key]
|
||||
self.data[key] = (time.monotonic(), value)
|
||||
self.cull()
|
||||
|
||||
def cull(self):
|
||||
for _, _ in self.iteritemsOlderThan(self.ttl):
|
||||
self.data.popitem(last=False)
|
||||
|
||||
def get(self, key, default=None):
|
||||
self.cull()
|
||||
if key in self.data:
|
||||
return self[key]
|
||||
return default
|
||||
|
||||
def __getitem__(self, key):
|
||||
self.cull()
|
||||
return self.data[key][1]
|
||||
|
||||
def __iter__(self):
|
||||
self.cull()
|
||||
return iter(self.data)
|
||||
|
||||
def __repr__(self):
|
||||
self.cull()
|
||||
return repr(self.data)
|
||||
|
||||
def iteritemsOlderThan(self, secondsOld):
|
||||
minBirthday = time.monotonic() - secondsOld
|
||||
zipped = self._tripleIterable()
|
||||
matches = takewhile(lambda r: minBirthday >= r[1], zipped)
|
||||
return list(map(operator.itemgetter(0, 2), matches))
|
||||
|
||||
def _tripleIterable(self):
|
||||
ikeys = self.data.keys()
|
||||
ibirthday = map(operator.itemgetter(0), self.data.values())
|
||||
ivalues = map(operator.itemgetter(1), self.data.values())
|
||||
return zip(ikeys, ibirthday, ivalues)
|
||||
|
||||
def items(self):
|
||||
self.cull()
|
||||
ikeys = self.data.keys()
|
||||
ivalues = map(operator.itemgetter(1), self.data.values())
|
||||
return zip(ikeys, ivalues)
|
||||
57
kademlia/utils.py
Normal file
57
kademlia/utils.py
Normal file
|
|
@ -0,0 +1,57 @@
|
|||
"""
|
||||
General catchall for functions that don't make sense as methods.
|
||||
"""
|
||||
import hashlib
|
||||
import operator
|
||||
import asyncio
|
||||
|
||||
|
||||
async def gather_dict(d):
|
||||
cors = list(d.values())
|
||||
results = await asyncio.gather(*cors)
|
||||
return dict(zip(d.keys(), results))
|
||||
|
||||
|
||||
def digest(s):
|
||||
if not isinstance(s, bytes):
|
||||
s = str(s).encode('utf8')
|
||||
return hashlib.sha1(s).digest()
|
||||
|
||||
|
||||
class OrderedSet(list):
|
||||
"""
|
||||
Acts like a list in all ways, except in the behavior of the
|
||||
:meth:`push` method.
|
||||
"""
|
||||
|
||||
def push(self, thing):
|
||||
"""
|
||||
1. If the item exists in the list, it's removed
|
||||
2. The item is pushed to the end of the list
|
||||
"""
|
||||
if thing in self:
|
||||
self.remove(thing)
|
||||
self.append(thing)
|
||||
|
||||
|
||||
def sharedPrefix(args):
|
||||
"""
|
||||
Find the shared prefix between the strings.
|
||||
|
||||
For instance:
|
||||
|
||||
sharedPrefix(['blahblah', 'blahwhat'])
|
||||
|
||||
returns 'blah'.
|
||||
"""
|
||||
i = 0
|
||||
while i < min(map(len, args)):
|
||||
if len(set(map(operator.itemgetter(i), args))) != 1:
|
||||
break
|
||||
i += 1
|
||||
return args[0][:i]
|
||||
|
||||
|
||||
def bytesToBitString(bites):
|
||||
bits = [bin(bite)[2:].rjust(8, '0') for bite in bites]
|
||||
return "".join(bits)
|
||||
Loading…
Reference in New Issue
Block a user