def setup(self, config, cache_dir):
"""Setup all the Khashmir sub-modules.
@type config: C{dictionary}
@param config: the configuration parameters for the DHT
@type cache_dir: C{string}
@param cache_dir: the directory to store all files in
"""
self.config = config
self.port = config['PORT']
self.store = DB(os.path.join(cache_dir, 'khashmir.' + str(self.port) + '.db'))
self.node = self._loadSelfNode('', self.port)
self.table = KTable(self.node, config)
self.token_secrets = [newID()]
self.stats = StatsLogger(self.table, self.store)
# Start listening
self.udp = krpc.hostbroker(self, self.stats, config)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(self.port, self.udp)
# Load the routing table and begin checkpointing
self._loadRoutingTable()
self.refreshTable(force = True)
self.next_checkpoint = reactor.callLater(60, self.checkpoint)
def setup(self, host, port, db='khashmir.db'):
self._findDB(db)
self.port = port
self.node = self._loadSelfNode(host, port)
self.table = KTable(self.node)
#self.app = service.Application("krpc")
self.udp = krpc.hostbroker(self)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(port, self.udp)
self.last = time.time()
self._loadRoutingTable()
KeyExpirer(store=self.store)
self.refreshTable(force=1)
reactor.callLater(60, self.checkpoint, (1, ))
def _loadRoutingTable(self):
"""Load routing table from the database"""
self.table = KTable(self.node)
c = self.store.cursor()
c.execute("select id, host, port from nodes")
for row in c:
n = self.Node().init(str(row[0]), row[1], row[2])
self.table.insertNode(n, contacted = False)
c.close()
if DEBUG:
print("Debug: DHT - nodes loaded:", self.stats())
def setup(self, host, port, db='khashmir.db'):
self._findDB(db)
self.port = port
self.node = self._loadSelfNode(host, port)
self.table = KTable(self.node)
#self.app = service.Application("krpc")
self.udp = krpc.hostbroker(self)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(port, self.udp)
self.last = time.time()
self._loadRoutingTable()
KeyExpirer(store=self.store)
self.refreshTable(force=1)
reactor.callLater(60, self.checkpoint, (1,))
def _load(self):
do_load = False
try:
s = open(os.path.join(self.ddir, "routing_table"), 'r').read()
dict = bdecode(s)
except:
id = newID()
else:
id = dict['id']
do_load = True
self.node = self._Node(self.udp.connectionForAddr).init(id, self.host, self.port)
self.table = KTable(self.node)
if do_load:
self._loadRoutingTable(dict['rt'])
def _load(self):
do_load = False
try:
s = open(os.path.join(self.ddir, "routing_table"), 'r').read()
dict = bdecode(s)
except:
id = newID()
else:
id = dict['id']
do_load = True
self.node = self._Node(self.udp.connectionForAddr).init(id, self.host, self.port)
self.table = KTable(self.node)
if do_load:
self._loadRoutingTable(dict['rt'])
class KhashmirBase:
_Node = KNodeBase
def __init__(self, host, port, data_dir, rawserver=None, max_ul_rate=1024, checkpoint=True, errfunc=None, rlcount=foo, config={'pause':False, 'max_rate_period':20}):
if rawserver:
self.rawserver = rawserver
else:
self.flag = Event()
d = dict([(x[0],x[1]) for x in common_options + rare_options])
self.rawserver = RawServer(self.flag, d)
self.max_ul_rate = max_ul_rate
self.socket = None
self.config = config
self.setup(host, port, data_dir, rlcount, checkpoint)
def setup(self, host, port, data_dir, rlcount, checkpoint=True):
self.host = host
self.port = port
self.ddir = data_dir
self.store = KStore()
self.pingcache = {}
self.socket = self.rawserver.create_udpsocket(self.port, self.host, False)
self.udp = krpc.hostbroker(self, (self.host, self.port), self.socket, self.rawserver.add_task, self.max_ul_rate, self.config, rlcount)
self._load()
self.rawserver.start_listening_udp(self.socket, self.udp)
self.last = time()
KeyExpirer(self.store, self.rawserver.add_task)
self.refreshTable(force=1)
if checkpoint:
self.rawserver.add_task(self.findCloseNodes, 30, (lambda a: a, True))
self.rawserver.add_task(self.checkpoint, 60, (1,))
def Node(self):
n = self._Node(self.udp.connectionForAddr)
n.table = self
return n
def __del__(self):
if self.socket is not None:
self.rawserver.stop_listening_udp(self.socket)
self.socket.close()
def _load(self):
do_load = False
try:
s = open(os.path.join(self.ddir, "routing_table"), 'r').read()
dict = bdecode(s)
except:
id = newID()
else:
id = dict['id']
do_load = True
self.node = self._Node(self.udp.connectionForAddr).init(id, self.host, self.port)
self.table = KTable(self.node)
if do_load:
self._loadRoutingTable(dict['rt'])
def checkpoint(self, auto=0):
d = {}
d['id'] = self.node.id
d['rt'] = self._dumpRoutingTable()
try:
f = open(os.path.join(self.ddir, "routing_table"), 'wb')
f.write(bencode(d))
f.close()
except:
#XXX real error here
print ">>> unable to dump routing table!", str(e)
pass
if auto:
self.rawserver.add_task(self.checkpoint,
randrange(int(const.CHECKPOINT_INTERVAL * .9),
int(const.CHECKPOINT_INTERVAL * 1.1)),
(1,))
def _loadRoutingTable(self, nodes):
"""
load routing table nodes from database
it's usually a good idea to call refreshTable(force=1) after loading the table
"""
for rec in nodes:
n = self.Node().initWithDict(rec)
self.table.insertNode(n, contacted=0, nocheck=True)
def _dumpRoutingTable(self):
"""
save routing table nodes to the database
"""
l = []
for bucket in self.table.buckets:
for node in bucket.l:
l.append({'id':node.id, 'host':node.host, 'port':node.port, 'age':int(node.age)})
return l
def _addContact(self, host, port, callback=None):
"""
ping this node and add the contact info to the table on pong!
"""
n =self.Node().init(const.NULL_ID, host, port)
try:
self.sendPing(n, callback=callback)
except krpc.KRPCSelfNodeError:
# our own node
pass
#######
####### LOCAL INTERFACE - use these methods!
def addContact(self, ip, port, callback=None):
"""
ping this node and add the contact info to the table on pong!
"""
if ip_pat.match(ip):
self._addContact(ip, port)
else:
def go(ip=ip, port=port):
ip = gethostbyname(ip)
self.rawserver.external_add_task(self._addContact, 0, (ip, port))
t = Thread(target=go)
t.start()
## this call is async!
def findNode(self, id, callback, errback=None):
""" returns the contact info for node, or the k closest nodes, from the global table """
# get K nodes out of local table/cache, or the node we want
nodes = self.table.findNodes(id, invalid=True)
l = [x for x in nodes if x.invalid]
if len(l) > 4:
nodes = sample(l , 4) + self.table.findNodes(id, invalid=False)[:4]
d = Deferred()
if errback:
d.addCallbacks(callback, errback)
else:
d.addCallback(callback)
if len(nodes) == 1 and nodes[0].id == id :
d.callback(nodes)
else:
# create our search state
state = FindNode(self, id, d.callback, self.rawserver.add_task)
self.rawserver.external_add_task(state.goWithNodes, 0, (nodes,))
def insertNode(self, n, contacted=1):
"""
insert a node in our local table, pinging oldest contact in bucket, if necessary
If all you have is a host/port, then use addContact, which calls this method after
receiving the PONG from the remote node. The reason for the seperation is we can't insert
a node into the table without it's peer-ID. That means of course the node passed into this
method needs to be a properly formed Node object with a valid ID.
"""
old = self.table.insertNode(n, contacted=contacted)
if old and old != n:
if not old.inPing():
self.checkOldNode(old, n, contacted)
else:
l = self.pingcache.get(old.id, [])
if len(l) < 10 or contacted:
l.append((n, contacted))
self.pingcache[old.id] = l
def checkOldNode(self, old, new, contacted=False):
## these are the callbacks used when we ping the oldest node in a bucket
def cmp(a, b):
if a[1] == 1 and b[1] == 0:
return -1
elif b[1] == 1 and a[1] == 0:
return 1
else:
return 0
def _staleNodeHandler(dict, old=old, new=new, contacted=contacted):
""" called if the pinged node never responds """
if old.fails >= 2:
l = self.pingcache.get(old.id, [])
l.sort(cmp)
if l:
n, nc = l[0]
if (not contacted) and nc:
l = l[1:] + [(new, contacted)]
new = n
contacted = nc
o = self.table.replaceStaleNode(old, new)
if o and o != new:
self.checkOldNode(o, new)
try:
self.pingcache[o.id] = self.pingcache[old.id]
del(self.pingcache[old.id])
except KeyError:
pass
else:
if l:
del(self.pingcache[old.id])
l.sort(cmp)
for node in l:
self.insertNode(node[0], node[1])
else:
l = self.pingcache.get(old.id, [])
if l:
del(self.pingcache[old.id])
self.insertNode(new, contacted)
for node in l:
self.insertNode(node[0], node[1])
def _notStaleNodeHandler(dict, old=old, new=new, contacted=contacted):
""" called when we get a pong from the old node """
self.table.insertNode(old, True)
self.insertNode(new, contacted)
l = self.pingcache.get(old.id, [])
l.sort(cmp)
for node in l:
self.insertNode(node[0], node[1])
try:
del(self.pingcache[old.id])
except KeyError:
pass
try:
df = old.ping(self.node.id)
except krpc.KRPCSelfNodeError:
pass
df.addCallbacks(_notStaleNodeHandler, _staleNodeHandler)
def sendPing(self, node, callback=None):
"""
ping a node
"""
try:
df = node.ping(self.node.id)
except krpc.KRPCSelfNodeError:
pass
else:
## these are the callbacks we use when we issue a PING
def _pongHandler(dict, node=node, table=self.table, callback=callback):
_krpc_sender = dict['_krpc_sender']
dict = dict['rsp']
sender = {'id' : dict['id']}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
table.insertNode(n)
if callback:
callback()
def _defaultPong(err, node=node, table=self.table, callback=callback):
if callback:
callback()
df.addCallbacks(_pongHandler,_defaultPong)
def findCloseNodes(self, callback=lambda a: a, auto=False):
"""
This does a findNode on the ID one away from our own.
This will allow us to populate our table with nodes on our network closest to our own.
This is called as soon as we start up with an empty table
"""
if not self.config['pause']:
id = self.node.id[:-1] + chr((ord(self.node.id[-1]) + 1) % 256)
self.findNode(id, callback)
if auto:
if not self.config['pause']:
self.refreshTable()
self.rawserver.external_add_task(self.findCloseNodes, randrange(int(const.FIND_CLOSE_INTERVAL *0.9),
int(const.FIND_CLOSE_INTERVAL *1.1)), (lambda a: True, True))
def refreshTable(self, force=0):
"""
force=1 will refresh table regardless of last bucket access time
"""
def callback(nodes):
pass
refresh = [bucket for bucket in self.table.buckets if force or (len(bucket.l) < K) or len(filter(lambda a: a.invalid, bucket.l)) or (time() - bucket.lastAccessed > const.BUCKET_STALENESS)]
for bucket in refresh:
id = newIDInRange(bucket.min, bucket.max)
self.findNode(id, callback)
def stats(self):
"""
Returns (num_contacts, num_nodes)
num_contacts: number contacts in our routing table
num_nodes: number of nodes estimated in the entire dht
"""
num_contacts = reduce(lambda a, b: a + len(b.l), self.table.buckets, 0)
num_nodes = const.K * (2**(len(self.table.buckets) - 1))
return {'num_contacts':num_contacts, 'num_nodes':num_nodes}
def krpc_ping(self, id, _krpc_sender):
sender = {'id' : id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
self.insertNode(n, contacted=0)
return {"id" : self.node.id}
def krpc_find_node(self, target, id, _krpc_sender):
nodes = self.table.findNodes(target, invalid=False)
nodes = map(lambda node: node.senderDict(), nodes)
sender = {'id' : id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
self.insertNode(n, contacted=0)
return {"nodes" : packNodes(nodes), "id" : self.node.id}
class KhashmirBase(protocol.Factory):
__slots__ = ('listener', 'node', 'table', 'store', 'app', 'last', 'protocol')
_Node = KNodeBase
def __init__(self, host, port, db='khashmir.db'):
self.setup(host, port, db)
def setup(self, host, port, db='khashmir.db'):
self._findDB(db)
self.port = port
self.node = self._loadSelfNode(host, port)
self.table = KTable(self.node)
#self.app = service.Application("krpc")
self.udp = krpc.hostbroker(self)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(port, self.udp)
self.last = time.time()
self._loadRoutingTable()
KeyExpirer(store=self.store)
self.refreshTable(force=1)
reactor.callLater(60, self.checkpoint, (1,))
def Node(self):
n = self._Node()
n.table = self.table
return n
def __del__(self):
self.listenport.stopListening()
def _loadSelfNode(self, host, port):
c = self.store.cursor()
c.execute('select id from self where num = 0;')
if c.rowcount > 0:
id = c.fetchone()[0]
else:
id = newID()
return self._Node().init(id, host, port)
def _saveSelfNode(self):
c = self.store.cursor()
c.execute('delete from self where num = 0;')
c.execute("insert into self values (0, ?);", (sqlite.Binary(self.node.id), ))
self.store.commit()
def checkpoint(self, auto=0):
self._saveSelfNode()
self._dumpRoutingTable()
self.refreshTable()
if auto:
reactor.callLater(randrange(int(const.CHECKPOINT_INTERVAL * .9), int(const.CHECKPOINT_INTERVAL * 1.1)), self.checkpoint, (1,))
def _findDB(self, db):
import os
try:
os.stat(db)
except OSError:
self._createNewDB(db)
else:
self._loadDB(db)
self.store.text_factory = lambda x: str(x)
self.store.row_factory = sqlite.Row
def _loadDB(self, db):
try:
self.store = sqlite.connect(db)
#self.store.autocommit = 0
except:
import traceback
raise KhashmirDBExcept, "Couldn't open DB", traceback.exc_traceback
def _createNewDB(self, db):
self.store = sqlite.connect(db)
s = """
create table kv (key binary, value binary, time timestamp, primary key (key, value));
create index kv_key on kv(key);
create index kv_timestamp on kv(time);
create table nodes (id binary primary key, host text, port number);
create table self (num number primary key, id binary);
"""
c = self.store.cursor()
c.executescript(s)
self.store.commit()
def _dumpRoutingTable(self):
"""
save routing table nodes to the database
"""
c = self.store.cursor()
c.execute("delete from nodes where id not NULL;")
for bucket in self.table.buckets:
for node in bucket.l:
c.execute("insert into nodes values (?, ?, ?);", (sqlite.Binary(node.id), node.host, node.port))
self.store.commit()
def _loadRoutingTable(self):
"""
load routing table nodes from database
it's usually a good idea to call refreshTable(force=1) after loading the table
"""
c = self.store.cursor()
c.execute("select * from nodes;")
for rec in c.fetchall():
n = self.Node().initWithDict({'id':rec[0], 'host':rec[1], 'port':int(rec[2])})
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.table.insertNode(n, contacted=0)
#######
####### LOCAL INTERFACE - use these methods!
def addContact(self, host, port, callback=None):
"""
ping this node and add the contact info to the table on pong!
"""
n =self.Node().init(const.NULL_ID, host, port)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.sendPing(n, callback=callback)
## this call is async!
def findNode(self, id, callback, errback=None):
""" returns the contact info for node, or the k closest nodes, from the global table """
# get K nodes out of local table/cache, or the node we want
nodes = self.table.findNodes(id)
d = Deferred()
if errback:
d.addCallbacks(callback, errback)
else:
d.addCallback(callback)
if len(nodes) == 1 and nodes[0].id == id :
d.callback(nodes)
else:
# create our search state
state = FindNode(self, id, d.callback)
reactor.callFromThread(state.goWithNodes, nodes)
def insertNode(self, n, contacted=1):
"""
insert a node in our local table, pinging oldest contact in bucket, if necessary
If all you have is a host/port, then use addContact, which calls this method after
receiving the PONG from the remote node. The reason for the seperation is we can't insert
a node into the table without it's peer-ID. That means of course the node passed into this
method needs to be a properly formed Node object with a valid ID.
"""
old = self.table.insertNode(n, contacted=contacted)
if old and (time.time() - old.lastSeen) > const.MIN_PING_INTERVAL and old.id != self.node.id:
# the bucket is full, check to see if old node is still around and if so, replace it
## these are the callbacks used when we ping the oldest node in a bucket
def _staleNodeHandler(oldnode=old, newnode = n):
""" called if the pinged node never responds """
self.table.replaceStaleNode(old, newnode)
def _notStaleNodeHandler(dict, old=old):
""" called when we get a pong from the old node """
dict = dict['rsp']
if dict['id'] == old.id:
self.table.justSeenNode(old.id)
df = old.ping(self.node.id)
df.addCallbacks(_notStaleNodeHandler, _staleNodeHandler)
def sendPing(self, node, callback=None):
"""
ping a node
"""
df = node.ping(self.node.id)
## these are the callbacks we use when we issue a PING
def _pongHandler(dict, node=node, table=self.table, callback=callback):
_krpc_sender = dict['_krpc_sender']
dict = dict['rsp']
sender = {'id' : dict['id']}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
table.insertNode(n)
if callback:
callback()
def _defaultPong(err, node=node, table=self.table, callback=callback):
table.nodeFailed(node)
if callback:
callback()
df.addCallbacks(_pongHandler,_defaultPong)
def findCloseNodes(self, callback=lambda a: None):
"""
This does a findNode on the ID one away from our own.
This will allow us to populate our table with nodes on our network closest to our own.
This is called as soon as we start up with an empty table
"""
id = self.node.id[:-1] + chr((ord(self.node.id[-1]) + 1) % 256)
self.findNode(id, callback)
def refreshTable(self, force=0):
"""
force=1 will refresh table regardless of last bucket access time
"""
def callback(nodes):
pass
for bucket in self.table.buckets:
if force or (time.time() - bucket.lastAccessed >= const.BUCKET_STALENESS):
id = newIDInRange(bucket.min, bucket.max)
self.findNode(id, callback)
def stats(self):
"""
Returns (num_contacts, num_nodes)
num_contacts: number contacts in our routing table
num_nodes: number of nodes estimated in the entire dht
"""
num_contacts = reduce(lambda a, b: a + len(b.l), self.table.buckets, 0)
num_nodes = const.K * (2**(len(self.table.buckets) - 1))
return (num_contacts, num_nodes)
def krpc_ping(self, id, _krpc_sender):
sender = {'id' : id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.insertNode(n, contacted=0)
return {"id" : self.node.id}
def krpc_find_node(self, target, id, _krpc_sender):
nodes = self.table.findNodes(target)
nodes = map(lambda node: node.senderDict(), nodes)
sender = {'id' : id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.insertNode(n, contacted=0)
return {"nodes" : nodes, "id" : self.node.id}
class KhashmirBase(protocol.Factory):
__slots__ = ('listener', 'node', 'table', 'store', 'app', 'last',
'protocol')
_Node = KNodeBase
def __init__(self, host, port, db='khashmir.db'):
self.setup(host, port, db)
def setup(self, host, port, db='khashmir.db'):
self._findDB(db)
self.port = port
self.node = self._loadSelfNode(host, port)
self.table = KTable(self.node)
#self.app = service.Application("krpc")
self.udp = krpc.hostbroker(self)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(port, self.udp)
self.last = time.time()
self._loadRoutingTable()
KeyExpirer(store=self.store)
self.refreshTable(force=1)
reactor.callLater(60, self.checkpoint, (1, ))
def Node(self):
n = self._Node()
n.table = self.table
return n
def __del__(self):
self.listenport.stopListening()
def _loadSelfNode(self, host, port):
c = self.store.cursor()
c.execute('select id from self where num = 0;')
if c.rowcount > 0:
id = c.fetchone()[0]
else:
id = newID()
return self._Node().init(id, host, port)
def _saveSelfNode(self):
c = self.store.cursor()
c.execute('delete from self where num = 0;')
c.execute("insert into self values (0, %s);",
sqlite.encode(self.node.id))
self.store.commit()
def checkpoint(self, auto=0):
self._saveSelfNode()
self._dumpRoutingTable()
self.refreshTable()
if auto:
reactor.callLater(
randrange(int(const.CHECKPOINT_INTERVAL * .9),
int(const.CHECKPOINT_INTERVAL * 1.1)),
self.checkpoint, (1, ))
def _findDB(self, db):
import os
try:
os.stat(db)
except OSError:
self._createNewDB(db)
else:
self._loadDB(db)
def _loadDB(self, db):
try:
self.store = sqlite.connect(db=db)
#self.store.autocommit = 0
except:
import traceback
raise KhashmirDBExcept, "Couldn't open DB", traceback.exc_traceback
def _createNewDB(self, db):
self.store = sqlite.connect(db=db)
s = """
create table kv (key binary, value binary, time timestamp, primary key (key, value));
create index kv_key on kv(key);
create index kv_timestamp on kv(time);
create table nodes (id binary primary key, host text, port number);
create table self (num number primary key, id binary);
"""
c = self.store.cursor()
c.execute(s)
self.store.commit()
def _dumpRoutingTable(self):
"""
save routing table nodes to the database
"""
c = self.store.cursor()
c.execute("delete from nodes where id not NULL;")
for bucket in self.table.buckets:
for node in bucket.l:
c.execute("insert into nodes values (%s, %s, %s);",
(sqlite.encode(node.id), node.host, node.port))
self.store.commit()
def _loadRoutingTable(self):
"""
load routing table nodes from database
it's usually a good idea to call refreshTable(force=1) after loading the table
"""
c = self.store.cursor()
c.execute("select * from nodes;")
for rec in c.fetchall():
n = self.Node().initWithDict({
'id': rec[0],
'host': rec[1],
'port': int(rec[2])
})
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.table.insertNode(n, contacted=0)
#######
####### LOCAL INTERFACE - use these methods!
def addContact(self, host, port, callback=None):
"""
ping this node and add the contact info to the table on pong!
"""
n = self.Node().init(const.NULL_ID, host, port)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.sendPing(n, callback=callback)
## this call is async!
def findNode(self, id, callback, errback=None):
""" returns the contact info for node, or the k closest nodes, from the global table """
# get K nodes out of local table/cache, or the node we want
nodes = self.table.findNodes(id)
d = Deferred()
if errback:
d.addCallbacks(callback, errback)
else:
d.addCallback(callback)
if len(nodes) == 1 and nodes[0].id == id:
d.callback(nodes)
else:
# create our search state
state = FindNode(self, id, d.callback)
reactor.callFromThread(state.goWithNodes, nodes)
def insertNode(self, n, contacted=1):
"""
insert a node in our local table, pinging oldest contact in bucket, if necessary
If all you have is a host/port, then use addContact, which calls this method after
receiving the PONG from the remote node. The reason for the seperation is we can't insert
a node into the table without it's peer-ID. That means of course the node passed into this
method needs to be a properly formed Node object with a valid ID.
"""
old = self.table.insertNode(n, contacted=contacted)
if old and (time.time() - old.lastSeen
) > const.MIN_PING_INTERVAL and old.id != self.node.id:
# the bucket is full, check to see if old node is still around and if so, replace it
## these are the callbacks used when we ping the oldest node in a bucket
def _staleNodeHandler(oldnode=old, newnode=n):
""" called if the pinged node never responds """
self.table.replaceStaleNode(old, newnode)
def _notStaleNodeHandler(dict, old=old):
""" called when we get a pong from the old node """
dict = dict['rsp']
if dict['id'] == old.id:
self.table.justSeenNode(old.id)
df = old.ping(self.node.id)
df.addCallbacks(_notStaleNodeHandler, _staleNodeHandler)
def sendPing(self, node, callback=None):
"""
ping a node
"""
df = node.ping(self.node.id)
## these are the callbacks we use when we issue a PING
def _pongHandler(dict, node=node, table=self.table, callback=callback):
_krpc_sender = dict['_krpc_sender']
dict = dict['rsp']
sender = {'id': dict['id']}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
table.insertNode(n)
if callback:
callback()
def _defaultPong(err, node=node, table=self.table, callback=callback):
table.nodeFailed(node)
if callback:
callback()
df.addCallbacks(_pongHandler, _defaultPong)
def findCloseNodes(self, callback=lambda a: None):
"""
This does a findNode on the ID one away from our own.
This will allow us to populate our table with nodes on our network closest to our own.
This is called as soon as we start up with an empty table
"""
id = self.node.id[:-1] + chr((ord(self.node.id[-1]) + 1) % 256)
self.findNode(id, callback)
def refreshTable(self, force=0):
"""
force=1 will refresh table regardless of last bucket access time
"""
def callback(nodes):
pass
for bucket in self.table.buckets:
if force or (time.time() - bucket.lastAccessed >=
const.BUCKET_STALENESS):
id = newIDInRange(bucket.min, bucket.max)
self.findNode(id, callback)
def stats(self):
"""
Returns (num_contacts, num_nodes)
num_contacts: number contacts in our routing table
num_nodes: number of nodes estimated in the entire dht
"""
num_contacts = reduce(lambda a, b: a + len(b.l), self.table.buckets, 0)
num_nodes = const.K * (2**(len(self.table.buckets) - 1))
return (num_contacts, num_nodes)
def krpc_ping(self, id, _krpc_sender):
sender = {'id': id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.insertNode(n, contacted=0)
return {"id": self.node.id}
def krpc_find_node(self, target, id, _krpc_sender):
nodes = self.table.findNodes(target)
nodes = map(lambda node: node.senderDict(), nodes)
sender = {'id': id}
sender['host'] = _krpc_sender[0]
sender['port'] = _krpc_sender[1]
n = self.Node().initWithDict(sender)
n.conn = self.udp.connectionForAddr((n.host, n.port))
self.insertNode(n, contacted=0)
return {"nodes": nodes, "id": self.node.id}
class Factory:
"""
Background functionality
"""
def __init__(self, host, port, dbDir, ipv6_enable = False, upnp = 0, natpmp = False):
self.host = host
self.port = port
self.dbDir = dbDir
self.store = None
self.rawserver = RawServer(self, host, port, ipv6_enable, upnp, natpmp)
self.tokensHandler = TokensHandler(self)
self.krpc = KRPC(self)
self.contacts = [] # [ip,] - contacts added by bittorrent
self.announce = {} # {ip:[hash,],} - nodes that announced us
def Node(self):
"""Create a new node"""
return KNode(self)
def start(self):
"""Start Factory"""
self.rawserver.add_task(self._init)
self.rawserver.add_task(self._checkpoint, 60)
self.rawserver.start()
self.rawserver.add_task(self._cleanDataBase, KEINITIAL_DELAY)
self.rawserver.add_task(self.refreshTable, 5, [True])
def _init(self):
"""Initialize Factory"""
self._loadDB()
self._loadSelfNode()
self._loadRoutingTable()
def _close(self):
"""Close Factory"""
self._updateDB()
self.rawserver.shutdown()
####################
# Database Handler
####################
def _loadDB(self):
"""Load the database"""
if DEBUG:
print("Debug: DHT - _loadDB")
# connect
self.store = sqlite3.connect(os.path.join(self.dbDir.encode("UTF-8"), "dht.db"))
self.store.text_factory = str
# create if neccacery
c = self.store.cursor()
statements = ["create table kv (key binary, value binary, age timestamp, primary key (key, value))",
"create table nodes (id binary primary key, host text, port number)",
"create table self (num number primary key, id binary, age timestamp)"]
try:
[c.execute(s) for s in statements]
except sqlite3.OperationalError:
pass
else:
self.store.commit()
c.close()
def _closeDB(self):
"""Close the database"""
self.store.close()
def _loadSelfNode(self):
"""Load the root node"""
if DEBUG:
print("Debug: DHT - loadSelfNode")
# Get ID
c = self.store.cursor()
c.execute('select id, age from self where num = 0')
data = c.fetchone()
# Clean if too old
if not data or time() - data[1] > 86400*5: # more than 5 days old
id = newID()
c.execute('delete from self')
c.execute("insert into self values (0, ?, ?)", (sqlite3.Binary(id), time()))
c.execute('delete from kv')
c.execute('delete from nodes')
self.store.commit()
else:
id = str(data[0])
c.close()
# Load self node
self.node = self.Node().init(id, self.host, self.port)
def _saveSelfNode(self):
"""Save the root node"""
if DEBUG:
print("Debug: DHT - saveSelfNode")
c = self.store.cursor()
c.execute('delete from self')
c.execute("insert into self values (0, ?, ?)", (sqlite3.Binary(self.node.id), time()))
self.store.commit()
c.close()
def _loadRoutingTable(self):
"""Load routing table from the database"""
self.table = KTable(self.node)
c = self.store.cursor()
c.execute("select id, host, port from nodes")
for row in c:
n = self.Node().init(str(row[0]), row[1], row[2])
self.table.insertNode(n, contacted = False)
c.close()
if DEBUG:
print("Debug: DHT - nodes loaded:", self.stats())
def _saveRoutingTable(self):
"""Save routing table nodes to the database"""
if DEBUG:
print("Debug: DHT - saveRoutingTable")
c = self.store.cursor()
c.execute("delete from nodes")
for bucket in self.table.buckets:
for node in bucket.l:
c.execute("insert into nodes values (?, ?, ?)", (sqlite3.Binary(node.id), node.host, node.port))
self.store.commit()
c.close()
def _updateDB(self):
"""Save info to database"""
if DEBUG:
print("Debug: DHT - updateDB")
self._saveSelfNode()
self._saveRoutingTable()
if DEBUG:
print("Debug: DHT - updateDB completed")
def _flushExpired(self):
"""Clean old values from database"""
c = self.store.cursor()
c.execute("delete from kv where age > ?", (KE_AGE,))
self.store.commit()
c.close()
def _retrieveValue(self, key):
"""Returns the value found for key in local table"""
values = []
c = self.store.cursor()
c.execute("select value from kv where key = ?", (sqlite3.Binary(key),))
for row in c:
values.append(str(row[0]))
c.close()
return values[:20]
def _storeValue(self, key, value):
"""Stores <key:value> pair in the database"""
c = self.store.cursor()
try:
c.execute("insert into kv values (?, ?, ?);", (sqlite3.Binary(key), sqlite3.Binary(value), time()))
except sqlite3.IntegrityError:
c.execute("update kv set age = ? where key = ? and value = ?", (time(), sqlite3.Binary(key), sqlite3.Binary(value)))
self.store.commit()
c.close()
####################
# Automatic updates
####################
def _checkpoint(self):
"""Make some saving and refreshing once in a while"""
if DEBUG:
print("Debug: DHT - checkpoint")
# Save DB to disk
self._updateDB()
# Find close nodes
self.findCloseNodes()
# Refresh Table
self.refreshTable()
self.rawserver.add_task(self._checkpoint, randrange(int(CHECKPOINT_INTERVAL * .9), int(CHECKPOINT_INTERVAL * 1.1)))
def _cleanDataBase(self):
self._flushExpired()
self.rawserver.add_task(self._cleanDataBase, KE_DELAY)
####################
# Interface
####################
def addContact(self, host, port):
"""
Ping this node and add the contact info to the table on pong!
"""
# Validation
if not isinstance(port, int):
port = int(port)
if not isinstance(host, str):
host = str(host)
if host in self.contacts:
return False
self.contacts.append(host)
# Add Contact
if is_valid_ip(host):
n = self.Node().init(NULL_ID, host, port)
self.sendPing(n)
else:
Thread(target = self.addRouterContact, args = [host, port]).start()
def addRouterContact(self, host, port):
try:
host = socket.gethostbyname(host)
except socket.error:
return False
n = self.Node().init(NULL_ID, host, port)
self.sendPing(n)
return True
def insertNode(self, n, contacted = True):
"""
Insert a node in our local table, pinging oldest contact in bucket, if necessary
If all you have is a host/port, then use addContact, which calls this method after
receiving the PONG from the remote node. The reason for the seperation is we can't insert
a node into the table without it's peer-ID. That means of course the node passed into this
method needs to be a properly formed Node object with a valid ID.
"""
old = self.table.insertNode(n, contacted = contacted)
if old and (clock() - old.lastSeen) > MIN_PING_INTERVAL and old.id != self.node.id:
# the bucket is full, check to see if old node is still around and if so, replace it
## these are the callbacks used when we ping the oldest node in a bucket
def _staleNodeHandler(oldnode=old, newnode = n):
""" called if the pinged node never responds """
self.table.replaceStaleNode(old, newnode)
def _notStaleNodeHandler(dict, old=old):
""" called when we get a pong from the old node """
dict = dict['rsp']
if dict['id'] == old.id:
self.table.justSeenNode(old.id)
try:
df = old.ping(self.node.id)
except KrpcGenericError:
_staleNodeHandler()
else:
df.addCallbacks(_notStaleNodeHandler, _staleNodeHandler)
def findCloseNodes(self, callback=lambda a: None):
"""
This does a findNode on the ID one away from our own.
This will allow us to populate our table with nodes on our network closest to our own.
This is called as soon as we start up with an empty table
"""
if DEBUG:
print("Debug: DHT - findCloseNodes")
id = self.node.id[:-1] + chr((ord(self.node.id[-1]) + 1) % 256)
self.findNode(id, callback)
def refreshTable(self, force = False, callback=lambda a: None):
"""
Refresh the table
force=True will refresh table regardless of last bucket access time
"""
if DEBUG:
print("Debug: DHT - refreshTable")
for bucket in self.table.buckets:
if force or (clock() - bucket.lastAccessed >= BUCKET_STALENESS):
id = newIDInRange(bucket.min, bucket.max)
self.findNode(id, callback)
def stats(self):
"""
Returns the number of contacts in our routing table
"""
return reduce(lambda a, b: a + len(b.l), self.table.buckets, 0)
####################
# RPC Handler
####################
def krpc_ping(self, id, _krpc_sender, **kwargs):
"""Incoming RPC: got ping"""
if len(id) != 20:
raise KrpcProtocolError("invalid id length: %d" % len(id))
n = self.Node().init(id, *_krpc_sender)
self.insertNode(n, contacted = False)
return {"id" : self.node.id}
def krpc_find_node(self, target, id, _krpc_sender, **kwargs):
"""Incoming RPC: got find_node"""
if len(id) != 20:
raise KrpcProtocolError("invalid id length: %d" % len(id))
if len(target) != 20:
raise KrpcProtocolError("invalid target id length: %d" % len(target))
nodes = self.table.findNodes(target)
nodes = map(lambda node: node.senderDict(), nodes)
n = self.Node().init(id, *_krpc_sender)
self.insertNode(n, contacted = False)
return {"nodes" : encodeNodes(nodes), "id" : self.node.id}
def krpc_get_peers(self, id, info_hash, _krpc_sender, **kwargs):
"""Incoming RPC: got get_peers"""
if len(id) != 20:
raise KrpcProtocolError("invalid id length: %d" % len(id))
if len(info_hash) != 20:
raise KrpcProtocolError("invalid info_hash length: %d" % len(info_hash))
if id == NULL_ID:
raise KrpcProtocolError("invalid id (NULL ID)")
n = self.Node().init(id, *_krpc_sender)
self.insertNode(n, contacted = False)
l = self._retrieveValue(info_hash)
if len(l) > 0:
return {'values' : l, "id": self.node.id,
"token" : self.tokensHandler.tokenToSend(info_hash, *_krpc_sender)}
else:
nodes = self.table.findNodes(info_hash)
nodes = map(lambda node: node.senderDict(), nodes)
return {'nodes' : encodeNodes(nodes), "id": self.node.id,
"token" : self.tokensHandler.tokenToSend(info_hash, *_krpc_sender)}
def krpc_announce_peer(self, id, info_hash, port, token, _krpc_sender, **kwargs):
"""Incoming RPC: got announce_peer"""
if len(id) != 20:
raise KrpcProtocolError("invalid id length: %d" % len(id))
if len(info_hash) != 20:
raise KrpcProtocolError("invalid info_hash length: %d" % len(info_hash))
if not isinstance(port, int):
try:
port = int(port)
except:
raise KrpcProtocolError("invalid port")
if not self.tokensHandler.checkToken(token, info_hash, *_krpc_sender):
raise KrpcProtocolError("Got invalid token")
# TODO: add a limit: maximum 3 info_hash announces per peer
ip = _krpc_sender[0]
if ip not in self.announce:
self.announce[ip] = []
if info_hash not in self.announce[ip]:
self.announce[ip].append(info_hash)
if len(self.announce[ip]) > 3:
raise KrpcGenericError("I only allow 3 infohash announces per peer!")
self._storeValue(info_hash, encodePeer((_krpc_sender[0], port)))
n = self.Node().init(id, *_krpc_sender)
self.insertNode(n, contacted = False)
return {"id" : self.node.id}
def sendPing(self, node, callback=None):
"""
Ping a node
"""
def _pongHandler(dict, node=node, table=self.table, callback=callback):
_krpc_sender = dict['_krpc_sender']
id = dict['rsp']['id']
if len(id) == 20:
n = self.Node().init(dict['rsp']['id'], *_krpc_sender)
table.insertNode(n)
if callback:
callback()
def _defaultPong(err, node=node, table=self.table, callback=callback):
table.nodeFailed(node)
if callback:
callback()
try:
df = node.ping(self.node.id)
except KrpcGenericError:
_defaultPong()
else:
df.addCallbacks(_pongHandler,_defaultPong)
def findNode(self, id, callback, errback = None):
"""
Returns the the k closest nodes to that ID from the global table
"""
# get K nodes out of local table/cache
nodes = self.table.findNodes(id)
d = Deferred()
if errback:
d.addCallbacks(callback, errback)
else:
d.addCallback(callback)
# create our search state
state = FindNode(self, id, d.callback)
self.rawserver.add_task(state.goWithNodes, 0, [nodes])
def getPeers(self, key, callback, searchlocal = True, donecallback = None):
"""
Get Value from global table
"""
if not hasattr(self, "store"):
self.rawserver.add_task(self.getPeers, 3, [key, callback, searchlocal, donecallback])
return
# get locals
if searchlocal:
l = self._retrieveValue(key)
if len(l) > 0:
l = decodePeers(l)
self.rawserver.add_task(callback, 0, [l])
else:
l = []
# create our search state
nodes = self.table.findNodes(key)
state = GetValue(self, key, callback, "getPeers", donecallback)
self.rawserver.add_task(state.goWithNodes, 0, [nodes, l])
def announcePeer(self, key, value, callback=None):
"""
Store Value in global table
"""
def _storeValueForKey(nodes, key=key, value=value, response=callback , table=self.table):
if not response:
# default callback
def _storedValueHandler(sender):
pass
response=_storedValueHandler
action = StoreValue(self, key, value, response, "announcePeer")
self.rawserver.add_task(action.goWithNodes, 0, [nodes])
# this call is asynch
self.findNode(key, _storeValueForKey)
def getPeersAndAnnounce(self, key, value, callback, searchlocal = True):
"""
Get value and store it
"""
def doneCallback(nodes, key = key, value = value):
action = StoreValue(self, key, value, None, "announcePeer")
self.rawserver.add_task(action.goWithNodes, 0, [nodes])
self.getPeers(key, callback, searchlocal, doneCallback)
class KhashmirBase(protocol.Factory):
"""The base Khashmir class, with base functionality and find node, no key-value mappings.
@type _Node: L{node.Node}
@ivar _Node: the knode implementation to use for this class of DHT
@type config: C{dictionary}
@ivar config: the configuration parameters for the DHT
@type pinging: C{dictionary}
@ivar pinging: the node's that are currently being pinged, keys are the
node id's, values are the Deferred or DelayedCall objects
@type port: C{int}
@ivar port: the port to listen on
@type store: L{db.DB}
@ivar store: the database to store nodes and key/value pairs in
@type node: L{node.Node}
@ivar node: this node
@type table: L{ktable.KTable}
@ivar table: the routing table
@type token_secrets: C{list} of C{string}
@ivar token_secrets: the current secrets to use to create tokens
@type stats: L{stats.StatsLogger}
@ivar stats: the statistics gatherer
@type udp: L{krpc.hostbroker}
@ivar udp: the factory for the KRPC protocol
@type listenport: L{twisted.internet.interfaces.IListeningPort}
@ivar listenport: the UDP listening port
@type next_checkpoint: L{twisted.internet.interfaces.IDelayedCall}
@ivar next_checkpoint: the delayed call for the next checkpoint
"""
_Node = KNodeBase
def __init__(self, config, cache_dir='/tmp'):
"""Initialize the Khashmir class and call the L{setup} method.
@type config: C{dictionary}
@param config: the configuration parameters for the DHT
@type cache_dir: C{string}
@param cache_dir: the directory to store all files in
(optional, defaults to the /tmp directory)
"""
self.config = None
self.pinging = {}
self.setup(config, cache_dir)
def setup(self, config, cache_dir):
"""Setup all the Khashmir sub-modules.
@type config: C{dictionary}
@param config: the configuration parameters for the DHT
@type cache_dir: C{string}
@param cache_dir: the directory to store all files in
"""
self.config = config
self.port = config['PORT']
self.store = DB(os.path.join(cache_dir, 'khashmir.' + str(self.port) + '.db'))
self.node = self._loadSelfNode('', self.port)
self.table = KTable(self.node, config)
self.token_secrets = [newID()]
self.stats = StatsLogger(self.table, self.store)
# Start listening
self.udp = krpc.hostbroker(self, self.stats, config)
self.udp.protocol = krpc.KRPC
self.listenport = reactor.listenUDP(self.port, self.udp)
# Load the routing table and begin checkpointing
self._loadRoutingTable()
self.refreshTable(force = True)
self.next_checkpoint = reactor.callLater(60, self.checkpoint)
def Node(self, id, host = None, port = None):
"""Create a new node.
@see: L{node.Node.__init__}
"""
n = self._Node(id, host, port)
n.table = self.table
n.conn = self.udp.connectionForAddr((n.host, n.port))
return n
def __del__(self):
"""Stop listening for packets."""
self.listenport.stopListening()
def _loadSelfNode(self, host, port):
"""Create this node, loading any previously saved one."""
id = self.store.getSelfNode()
if not id or not id.endswith(self.config['VERSION']):
id = newID(self.config['VERSION'])
return self._Node(id, host, port)
def checkpoint(self):
"""Perform some periodic maintenance operations."""
# Create a new token secret
self.token_secrets.insert(0, newID())
if len(self.token_secrets) > 3:
self.token_secrets.pop()
# Save some parameters for reloading
self.store.saveSelfNode(self.node.id)
self.store.dumpRoutingTable(self.table.buckets)
# DHT maintenance
self.store.expireValues(self.config['KEY_EXPIRE'])
self.refreshTable()
self.next_checkpoint = reactor.callLater(randrange(int(self.config['CHECKPOINT_INTERVAL'] * .9),
int(self.config['CHECKPOINT_INTERVAL'] * 1.1)),
self.checkpoint)
def _loadRoutingTable(self):
"""Load the previous routing table nodes from the database.
It's usually a good idea to call refreshTable(force = True) after
loading the table.
"""
nodes = self.store.getRoutingTable()
for rec in nodes:
n = self.Node(rec[0], rec[1], int(rec[2]))
self.table.insertNode(n, contacted = False)
#{ Local interface
def addContact(self, host, port, callback=None, errback=None):
"""Ping this node and add the contact info to the table on pong.
@type host: C{string}
@param host: the IP address of the node to contact
@type port: C{int}
@param port:the port of the node to contact
@type callback: C{method}
@param callback: the method to call with the results, it must take 1
parameter, the contact info returned by the node
(optional, defaults to doing nothing with the results)
@type errback: C{method}
@param errback: the method to call if an error occurs
(optional, defaults to calling the callback with the error)
"""
n = self.Node(NULL_ID, host, port)
self.sendJoin(n, callback=callback, errback=errback)
def findNode(self, id, callback):
"""Find the contact info for the K closest nodes in the global table.
@type id: C{string}
@param id: the target ID to find the K closest nodes of
@type callback: C{method}
@param callback: the method to call with the results, it must take 1
parameter, the list of K closest nodes
"""
# Mark the bucket as having been accessed
self.table.touch(id)
# Start with our node
nodes = [copy(self.node)]
# Start the finding nodes action
state = FindNode(self, id, callback, self.config, self.stats)
reactor.callLater(0, state.goWithNodes, nodes)
def insertNode(self, node, contacted = True):
"""Try to insert a node in our local table, pinging oldest contact if necessary.
If all you have is a host/port, then use L{addContact}, which calls this
method after receiving the PONG from the remote node. The reason for
the separation is we can't insert a node into the table without its
node ID. That means of course the node passed into this method needs
to be a properly formed Node object with a valid ID.
@type node: L{node.Node}
@param node: the new node to try and insert
@type contacted: C{boolean}
@param contacted: whether the new node is known to be good, i.e.
responded to a request (optional, defaults to True)
"""
# Don't add any local nodes to the routing table
if not self.config['LOCAL_OK'] and isLocal.match(node.host):
log.msg('Not adding local node to table: %s/%s' % (node.host, node.port))
return
old = self.table.insertNode(node, contacted=contacted)
if (isinstance(old, self._Node) and old.id != self.node.id and
(datetime.now() - old.lastSeen) >
timedelta(seconds=self.config['MIN_PING_INTERVAL'])):
# Bucket is full, check to see if old node is still available
df = self.sendPing(old)
df.addErrback(self._staleNodeHandler, old, node, contacted)
elif not old and not contacted:
# There's room, we just need to contact the node first
df = self.sendPing(node)
# Also schedule a future ping to make sure the node works
def rePing(newnode, self = self):
if newnode.id not in self.pinging:
self.pinging[newnode.id] = reactor.callLater(self.config['MIN_PING_INTERVAL'],
self.sendPing, newnode)
return newnode
df.addCallback(rePing)
def _staleNodeHandler(self, err, old, node, contacted):
"""The pinged node never responded, so replace it."""
self.table.invalidateNode(old)
self.insertNode(node, contacted)
return err
def nodeFailed(self, node):
"""Mark a node as having failed a request and schedule a future check.
@type node: L{node.Node}
@param node: the new node to try and insert
"""
exists = self.table.nodeFailed(node)
# If in the table, schedule a ping, if one isn't already sent/scheduled
if exists and node.id not in self.pinging:
self.pinging[node.id] = reactor.callLater(self.config['MIN_PING_INTERVAL'],
self.sendPing, node)
def sendPing(self, node):
"""Ping the node to see if it's still alive.
@type node: L{node.Node}
@param node: the node to send the join to
"""
# Check for a ping already underway
if (isinstance(self.pinging.get(node.id, None), DelayedCall) and
self.pinging[node.id].active()):
self.pinging[node.id].cancel()
elif isinstance(self.pinging.get(node.id, None), Deferred):
return self.pinging[node.id]
self.stats.startedAction('ping')
df = node.ping(self.node.id)
self.pinging[node.id] = df
df.addCallbacks(self._pingHandler, self._pingError,
callbackArgs = (node, datetime.now()),
errbackArgs = (node, datetime.now()))
return df
def _pingHandler(self, dict, node, start):
"""Node responded properly, update it and return the node object."""
self.stats.completedAction('ping', start)
del self.pinging[node.id]
# Create the node using the returned contact info
n = self.Node(dict['id'], dict['_krpc_sender'][0], dict['_krpc_sender'][1])
reactor.callLater(0, self.insertNode, n)
return n
def _pingError(self, err, node, start):
"""Error occurred, fail node."""
log.msg("action ping failed on %s/%s: %s" % (node.host, node.port, err.getErrorMessage()))
self.stats.completedAction('ping', start)
# Consume unhandled errors
self.pinging[node.id].addErrback(lambda ping_err: None)
del self.pinging[node.id]
self.nodeFailed(node)
return err
def sendJoin(self, node, callback=None, errback=None):
"""Join the DHT by pinging a bootstrap node.
@type node: L{node.Node}
@param node: the node to send the join to
@type callback: C{method}
@param callback: the method to call with the results, it must take 1
parameter, the contact info returned by the node
(optional, defaults to doing nothing with the results)
@type errback: C{method}
@param errback: the method to call if an error occurs
(optional, defaults to calling the callback with the error)
"""
if errback is None:
errback = callback
self.stats.startedAction('join')
df = node.join(self.node.id)
df.addCallbacks(self._joinHandler, self._joinError,
callbackArgs = (node, datetime.now()),
errbackArgs = (node, datetime.now()))
if callback:
df.addCallbacks(callback, errback)
def _joinHandler(self, dict, node, start):
"""Node responded properly, extract the response."""
self.stats.completedAction('join', start)
# Create the node using the returned contact info
n = self.Node(dict['id'], dict['_krpc_sender'][0], dict['_krpc_sender'][1])
reactor.callLater(0, self.insertNode, n)
return (dict['ip_addr'], dict['port'])
def _joinError(self, err, node, start):
"""Error occurred, fail node."""
log.msg("action join failed on %s/%s: %s" % (node.host, node.port, err.getErrorMessage()))
self.stats.completedAction('join', start)
self.nodeFailed(node)
return err
def findCloseNodes(self, callback=lambda a: None):
"""Perform a findNode on the ID one away from our own.
This will allow us to populate our table with nodes on our network
closest to our own. This is called as soon as we start up with an
empty table.
@type callback: C{method}
@param callback: the method to call with the results, it must take 1
parameter, the list of K closest nodes
(optional, defaults to doing nothing with the results)
"""
id = self.node.id[:-1] + chr((ord(self.node.id[-1]) + 1) % 256)
self.findNode(id, callback)
def refreshTable(self, force = False):
"""Check all the buckets for those that need refreshing.
@param force: refresh all buckets regardless of last bucket access time
(optional, defaults to False)
"""
def callback(nodes):
pass
for bucket in self.table.buckets:
if force or (datetime.now() - bucket.lastAccessed >
timedelta(seconds=self.config['BUCKET_STALENESS'])):
# Choose a random ID in the bucket and try and find it
id = newIDInRange(bucket.min, bucket.max)
self.findNode(id, callback)
def shutdown(self):
"""Closes the port and cancels pending later calls."""
self.listenport.stopListening()
try:
self.next_checkpoint.cancel()
except:
pass
for nodeid in self.pinging.keys():
if isinstance(self.pinging[nodeid], DelayedCall) and self.pinging[nodeid].active():
self.pinging[nodeid].cancel()
del self.pinging[nodeid]
self.store.close()
def getStats(self):
"""Gather the statistics for the DHT."""
return self.stats.formatHTML()
#{ Remote interface
def krpc_ping(self, id, _krpc_sender = None):
"""Pong with our ID.
@type id: C{string}
@param id: the node ID of the sender node
@type _krpc_sender: (C{string}, C{int})
@param _krpc_sender: the sender node's IP address and port
"""
if _krpc_sender is not None:
n = self.Node(id, _krpc_sender[0], _krpc_sender[1])
reactor.callLater(0, self.insertNode, n, False)
return {"id" : self.node.id}
def krpc_join(self, id, _krpc_sender = None):
"""Add the node by responding with its address and port.
@type id: C{string}
@param id: the node ID of the sender node
@type _krpc_sender: (C{string}, C{int})
@param _krpc_sender: the sender node's IP address and port
"""
if _krpc_sender is not None:
n = self.Node(id, _krpc_sender[0], _krpc_sender[1])
reactor.callLater(0, self.insertNode, n, False)
else:
_krpc_sender = ('127.0.0.1', self.port)
return {"ip_addr" : _krpc_sender[0], "port" : _krpc_sender[1], "id" : self.node.id}
def krpc_find_node(self, id, target, _krpc_sender = None):
"""Find the K closest nodes to the target in the local routing table.
@type target: C{string}
@param target: the target ID to find nodes for
@type id: C{string}
@param id: the node ID of the sender node
@type _krpc_sender: (C{string}, C{int})
@param _krpc_sender: the sender node's IP address and port
"""
if _krpc_sender is not None:
n = self.Node(id, _krpc_sender[0], _krpc_sender[1])
reactor.callLater(0, self.insertNode, n, False)
else:
_krpc_sender = ('127.0.0.1', self.port)
nodes = self.table.findNodes(target)
nodes = map(lambda node: node.contactInfo(), nodes)
token = sha(self.token_secrets[0] + _krpc_sender[0]).digest()
return {"nodes" : nodes, "token" : token, "id" : self.node.id}