1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
|
import random
import signal
import uuid
import pyuv
from fanoutclient import FanoutClient
from terminatorscanner import TerminatorScannerBasic
class PeerFinder(FanoutClient):
def __init__(self, process, address, loop=None):
super(PeerFinder, self).__init__(address, loop)
self.process = process
def join_handler(self, msg):
peer_id, port = msg.split('|')
if peer_id != self.process.client_id:
print "got peer at port %s" % port
self.process.peers.append((peer_id, port))
self.process.send_hello(peer_id, port)
def leave_handler(self, msg):
print 'peer %s has left' % msg
self.process.peers = [p for p in self.process.peers if p[0] != msg]
def control_handler(self, msg):
if msg == 'quit':
self.process.disconnect()
def on_connected(self):
print "peerfinder connected"
self.subscribe("join", self.join_handler)
self.subscribe("leave", self.leave_handler)
self.subscribe("control", self.control_handler)
self.announce("join", "%s|%s" % (self.process.client_id, self.process.port))
def disconnect(self):
def after_announce():
print 'LEFT'
super(PeerFinder, self).disconnect()
print 'LEAVING'
self.announce("leave", self.process.client_id, callback=after_announce)
# super(PeerFinder, self).disconnect()
class DistProcess(object):
def __init__(self, loop=None):
self.peers = []
self.epoch = 0
self.freq = -1
self.new_freq = None
self.freq_epoch = 0
self.client_id = str(uuid.uuid4())
if not loop:
loop = pyuv.Loop.default_loop()
self.loop = loop
self.signal_watchers = set()
for sig in (signal.SIGINT, signal.SIGTERM):
handle = pyuv.Signal(loop)
handle.start(self._signal_cb, sig)
self.signal_watchers.add(handle)
self.peerfinder = PeerFinder(self, ('127.0.0.1', 9898), loop)
self.port = random.randint(10000, 50000)
self.clients = []
self.incoming = TerminatorScannerBasic('\n')
self.cmd_handlers = {}
self.cmd_handlers['hello'] = self.handle_hello
self.cmd_handlers['update'] = self.handle_update
self.cmd_handlers['elect_me'] = self.handle_elect_me
self.cmd_handlers['you_have_my_vote'] = self.handle_you_have_my_vote
self.cmd_handlers['hop'] = self.handle_hop
self.votes = []
self.voting = False
self.vote_timer = pyuv.Timer(self.loop)
def start(self):
self.server = pyuv.TCP(self.loop)
self.server.bind(('127.0.0.1', self.port))
self.server.listen(self._on_connection)
self.update_timer = pyuv.Timer(self.loop)
self.update_timer.start(self._on_timer, random.random() * 5 + 5,
random.random() * 5 + 5)
print "listening on port %s" % self.port
self.peerfinder.connect()
def _on_connection(self, server, error):
# print 'client connected'
client = pyuv.TCP(server.loop)
server.accept(client)
self.clients.append(client)
client.start_read(self._on_read)
def _on_read(self, client, data, error):
if data is None:
client.close()
self.clients.remove(client)
return
self.incoming.handle_read(data)
while self.incoming.incoming:
msg = self.incoming.incoming.pop(0)
self._handle_msg(msg)
def _handle_msg(self, msg):
# print 'received data <%s>' % msg
cmd, data = msg.split(' ', 1)
if cmd in self.cmd_handlers:
handler = self.cmd_handlers[cmd]
handler(data)
def handle_hello(self, data):
peer, port = data.split()
print 'got hello from %s' % peer
self.peers.append((peer, int(port)))
def handle_update(self, data):
print 'got update %s' % data
epoch, freq, freq_epoch = [int(x) for x in data.split(':')]
if freq_epoch > self.freq_epoch:
print 'freq updated to %s (freq_epoch %s)' % (freq, freq_epoch)
self.freq_epoch = freq_epoch
self.freq = freq
if epoch > self.epoch:
print 'updating epoch to %s' % epoch
self.epoch = epoch
def handle_elect_me(self, data):
peer, epoch = data.split()
print '%s wants to be elected (epoch %s)' % (peer, epoch)
epoch = int(epoch)
if epoch > self.epoch:
self.epoch = epoch
if epoch == self.epoch:
self.send_vote(peer)
else:
pass
def handle_you_have_my_vote(self, data):
peer, epoch = data.split()
print '%s votes for me (epoch %s)' % (peer, epoch)
epoch = int(epoch)
if epoch == self.epoch:
self.votes.append(peer)
def handle_hop(self, data):
self.change_freq()
def disconnect(self):
self.peerfinder.disconnect()
[c.close() for c in self.clients]
[h.close() for h in self.signal_watchers]
self.update_timer.stop()
self.vote_timer.stop()
self.server.close()
def _signal_cb(self, handle, signum):
self.disconnect()
def _on_timer(self, timer):
# print '_on_timer'
if (self.freq < 0) and (self.epoch == 0):
self.change_freq()
return
if self.peers:
self.send_update()
def change_freq(self):
print 'trying to change freq'
self.epoch += 1
self.new_freq = random.randint(0, 1000)
self.send_elect()
def on_timer(timer):
print 'voting time is up'
timer.stop()
vote_count = len(self.votes)
peer_count = len(self.peers)
peer_count_m = peer_count
if peer_count % 2 != 0:
peer_count_m = peer_count_m + 1
if ((peer_count > 1) and (vote_count > peer_count/2)) or ((peer_count == 1) and (vote_count == 1)):
print "i'm elected"
self.freq_epoch = self.epoch
self.freq = self.new_freq
self.send_update()
self.votes = []
self.voting = False
self.vote_timer.start(on_timer, 5, 0)
def send_update(self):
if self.voting:
return
peer, port = random.choice(self.peers)
print 'sending update to port %s' % port
def on_connected(handle, error):
handle.write('update %s:%s:%s\n' % (self.epoch, self.freq, self.freq_epoch),
after_write)
def after_write(handle, error):
handle.close()
handle = pyuv.TCP(self.server.loop)
handle.connect(('127.0.0.1', int(port)), on_connected)
def send_elect(self):
print 'sending elects'
self.voting = True
def on_connected(handle, error):
handle.write('elect_me %s %s\n' % (self.client_id, self.epoch), after_write)
def after_write(handle, error):
handle.close()
for peer, port in self.peers:
handle = pyuv.TCP(self.server.loop)
handle.connect(('127.0.0.1', int(port)), on_connected)
def send_vote(self, peer_id):
peer = [p for p in self.peers if p[0] == peer_id]
if peer:
_, port = peer[0]
def on_connected(handle, error):
handle.write('you_have_my_vote %s %s\n' % (self.client_id, self.epoch), after_write)
def after_write(handle, error):
handle.close()
handle = pyuv.TCP(self.server.loop)
handle.connect(('127.0.0.1', int(port)), on_connected)
def send_hello(self, peer, port):
print 'saying hello to port %s' % port
def on_connected(handle, error):
handle.write('hello %s %s\n' % (self.client_id, self.port),
on_written)
def on_written(handle, error):
handle.close()
handle = pyuv.TCP(self.server.loop)
handle.connect(('127.0.0.1', int(port)), on_connected)
|
