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[electrum-nvc.git] / lib / interface.py
1 #!/usr/bin/env python
2 #
3 # Electrum - lightweight Bitcoin client
4 # Copyright (C) 2011 thomasv@gitorious
5 #
6 # This program is free software: you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation, either version 3 of the License, or
9 # (at your option) any later version.
10 #
11 # This program is distributed in the hope that it will be useful,
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 # GNU General Public License for more details.
15 #
16 # You should have received a copy of the GNU General Public License
17 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18
19
20 import random, socket, ast, re
21 import threading, traceback, sys, time, json, Queue
22
23 from version import ELECTRUM_VERSION
24 from util import print_error
25
26
27 DEFAULT_TIMEOUT = 5
28 DEFAULT_SERVERS = [ 
29     'electrum.novit.ro:50001:t', 
30     'electrum.pdmc.net:50001:t',
31     'ecdsa.org:50001:t',
32     'electrum.bitcoins.sk:50001:t',
33     'uncle-enzo.info:50001:t',
34     'electrum.bytesized-hosting.com:50001:t',
35     'electrum.bitcoin.cz:50001:t',
36     'electrum.bitfoo.org:50001:t'
37     ]
38
39 proxy_modes = ['socks4', 'socks5', 'http']
40
41
42 def pick_random_server():
43     return random.choice( DEFAULT_SERVERS )
44
45
46
47
48 class Interface(threading.Thread):
49
50     def register_callback(self, event, callback):
51         with self.lock:
52             if not self.callbacks.get(event):
53                 self.callbacks[event] = []
54             self.callbacks[event].append(callback)
55
56     def trigger_callback(self, event):
57         with self.lock:
58             callbacks = self.callbacks.get(event,[])[:]
59         if callbacks:
60             [callback() for callback in callbacks]
61
62     def init_server(self, host, port, proxy=None, use_ssl=True):
63         self.host = host
64         self.port = port
65         self.proxy = proxy
66         self.use_ssl = use_ssl
67         self.poll_interval = 1
68
69         #json
70         self.message_id = 0
71         self.unanswered_requests = {}
72
73
74
75     def queue_json_response(self, c):
76
77         # uncomment to debug
78         # print "<--",c
79
80         msg_id = c.get('id')
81         error = c.get('error')
82         
83         if error:
84             print "received error:", c
85             return
86
87         if msg_id is not None:
88             with self.lock: 
89                 method, params, channel = self.unanswered_requests.pop(msg_id)
90             result = c.get('result')
91         else:
92             # notification: find the channel(s)
93             method = c.get('method')
94             params = c.get('params')
95
96             if method == 'blockchain.numblocks.subscribe':
97                 result = params[0]
98                 params = []
99
100             elif method == 'blockchain.headers.subscribe':
101                 result = params[0]
102                 params = []
103
104             elif method == 'blockchain.address.subscribe':
105                 addr = params[0]
106                 result = params[1]
107                 params = [addr]
108
109             with self.lock:
110                 for k,v in self.subscriptions.items():
111                     if (method, params) in v:
112                         channel = k
113                         break
114                 else:
115                     print "received unexpected notification", method, params
116                     print self.subscriptions
117                     return
118                 
119         response_queue = self.responses[channel]
120         response_queue.put({'method':method, 'params':params, 'result':result, 'id':msg_id})
121
122
123
124     def get_response(self, channel='default', block=True, timeout=10000000000):
125         return self.responses[channel].get(block, timeout)
126
127     def register_channel(self, channel):
128         with self.lock:
129             self.responses[channel] = Queue.Queue()
130
131     def poke(self, channel):
132         self.responses[channel].put(None)
133
134
135     def init_http(self, host, port, proxy=None, use_ssl=True):
136         self.init_server(host, port, proxy, use_ssl)
137         self.session_id = None
138         self.connection_msg = ('https' if self.use_ssl else 'http') + '://%s:%d'%( self.host, self.port )
139         self.is_connected = True
140
141     def run_http(self):
142         self.is_connected = True
143         while self.is_connected:
144             try:
145                 if self.session_id:
146                     self.poll()
147                 time.sleep(self.poll_interval)
148             except socket.gaierror:
149                 break
150             except socket.error:
151                 break
152             except:
153                 traceback.print_exc(file=sys.stdout)
154                 break
155             
156         self.is_connected = False
157
158                 
159     def poll(self):
160         self.send([])
161
162
163     def send_http(self, messages, channel='default'):
164         import urllib2, json, time, cookielib
165         
166         if self.proxy:
167             import socks
168             socks.setdefaultproxy(proxy_modes.index(self.proxy["mode"]), self.proxy["host"], int(self.proxy["port"]) )
169             socks.wrapmodule(urllib2)
170
171         cj = cookielib.CookieJar()
172         opener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cj))
173         urllib2.install_opener(opener)
174
175         t1 = time.time()
176
177         data = []
178         for m in messages:
179             method, params = m
180             if type(params) != type([]): params = [params]
181             data.append( { 'method':method, 'id':self.message_id, 'params':params } )
182             self.unanswered_requests[self.message_id] = method, params, channel
183             self.message_id += 1
184
185         if data:
186             data_json = json.dumps(data)
187         else:
188             # poll with GET
189             data_json = None 
190
191             
192         headers = {'content-type': 'application/json'}
193         if self.session_id:
194             headers['cookie'] = 'SESSION=%s'%self.session_id
195
196         req = urllib2.Request(self.connection_msg, data_json, headers)
197         response_stream = urllib2.urlopen(req)
198
199         for index, cookie in enumerate(cj):
200             if cookie.name=='SESSION':
201                 self.session_id = cookie.value
202
203         response = response_stream.read()
204         self.bytes_received += len(response)
205         if response: 
206             response = json.loads( response )
207             if type(response) is not type([]):
208                 self.queue_json_response(response)
209             else:
210                 for item in response:
211                     self.queue_json_response(item)
212
213         if response: 
214             self.poll_interval = 1
215         else:
216             if self.poll_interval < 15: 
217                 self.poll_interval += 1
218         #print self.poll_interval, response
219
220         self.rtime = time.time() - t1
221         self.is_connected = True
222
223
224
225
226     def init_tcp(self, host, port, proxy=None, use_ssl=True):
227         self.init_server(host, port, proxy, use_ssl)
228
229         import ssl
230         global proxy_modes
231         self.connection_msg = "%s:%d"%(self.host,self.port)
232         if self.proxy is None:
233             s = socket.socket( socket.AF_INET, socket.SOCK_STREAM )
234         else:
235             self.connection_msg += " using proxy %s:%s:%s"%(self.proxy.get('mode'), self.proxy.get('host'), self.proxy.get('port'))
236             import socks
237             s = socks.socksocket()
238             s.setproxy(proxy_modes.index(self.proxy["mode"]), self.proxy["host"], int(self.proxy["port"]) )
239
240         if self.use_ssl:
241             s = ssl.wrap_socket(s, ssl_version=ssl.PROTOCOL_SSLv23)
242             
243         s.settimeout(2)
244         s.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1)
245
246         try:
247             s.connect(( self.host.encode('ascii'), int(self.port)))
248             s.settimeout(60)
249             self.s = s
250             self.is_connected = True
251         except:
252             self.is_connected = False
253             self.s = None
254
255
256     def run_tcp(self):
257         try:
258             out = ''
259             while self.is_connected:
260                 try: msg = self.s.recv(1024)
261                 except socket.timeout:
262                     print "timeout"
263                     # ping the server with server.version, as a real ping does not exist yet
264                     self.send([('server.version', [ELECTRUM_VERSION])])
265                     continue
266                 out += msg
267                 self.bytes_received += len(msg)
268                 if msg == '': 
269                     self.is_connected = False
270
271                 while True:
272                     s = out.find('\n')
273                     if s==-1: break
274                     c = out[0:s]
275                     out = out[s+1:]
276                     c = json.loads(c)
277                     self.queue_json_response(c)
278
279         except:
280             traceback.print_exc(file=sys.stdout)
281
282         self.is_connected = False
283
284
285     def send_tcp(self, messages, channel='default'):
286         """return the ids of the requests that we sent"""
287         out = ''
288         ids = []
289         for m in messages:
290             method, params = m 
291             request = json.dumps( { 'id':self.message_id, 'method':method, 'params':params } )
292             self.unanswered_requests[self.message_id] = method, params, channel
293             ids.append(self.message_id)
294             # uncomment to debug
295             # print "-->",request
296             self.message_id += 1
297             out += request + '\n'
298         while out:
299             try:
300                 sent = self.s.send( out )
301                 out = out[sent:]
302             except:
303                 # this happens when we get disconnected
304                 print "Not connected, cannot send"
305                 return None
306         return ids
307
308
309
310     def __init__(self, config=None, loop=False):
311
312         if config is None:
313             from simple_config import SimpleConfig
314             config = SimpleConfig()
315
316         threading.Thread.__init__(self)
317         self.daemon = True
318         self.loop = loop
319         self.config = config
320         self.connect_event = threading.Event()
321
322         self.subscriptions = {}
323         self.responses = {}
324         self.responses['default'] = Queue.Queue()
325
326         self.callbacks = {}
327         self.lock = threading.Lock()
328
329         self.servers = [] # actual list from IRC
330         self.rtime = 0
331         self.bytes_received = 0
332
333
334
335     def init_interface(self):
336         if self.config.get('server'):
337             self.init_with_server(self.config)
338         else:
339             print "Using random server..."
340             servers = DEFAULT_SERVERS[:]
341             while servers:
342                 server = random.choice( servers )
343                 servers.remove(server)
344                 self.config.set_key('server', server, False)
345                 self.init_with_server(self.config)
346                 if self.is_connected: break
347
348             if not servers:
349                 print 'no server available'
350                 self.is_connected = False
351                 self.connect_event.set() # to finish start
352                 self.server = 'ecdsa.org:50001:t'
353                 self.proxy = None
354                 return
355
356         self.connect_event.set()
357         if self.is_connected:
358             self.send([('server.version', [ELECTRUM_VERSION])])
359             self.trigger_callback('connected')
360         else:
361             self.trigger_callback('notconnected')
362             #print_error("Failed to connect " + self.connection_msg)
363
364
365     def init_with_server(self, config):
366             
367         s = config.get('server')
368         host, port, protocol = s.split(':')
369         port = int(port)
370
371         self.protocol = protocol
372         proxy = self.parse_proxy_options(config.get('proxy'))
373         self.server = host + ':%d:%s'%(port, protocol)
374
375         #print protocol, host, port
376         if protocol in 'st':
377             self.init_tcp(host, port, proxy, use_ssl=(protocol=='s'))
378         elif protocol in 'gh':
379             self.init_http(host, port, proxy, use_ssl=(protocol=='g'))
380         else:
381             raise BaseException('Unknown protocol: %s'%protocol)
382
383
384     def send(self, messages, channel='default'):
385
386         sub = []
387         for message in messages:
388             m, v = message
389             if m[-10:] == '.subscribe':
390                 sub.append(message)
391
392         if sub:
393             with self.lock:
394                 if self.subscriptions.get(channel) is None: 
395                     self.subscriptions[channel] = []
396                 self.subscriptions[channel] += sub
397
398         if self.protocol in 'st':
399             with self.lock:
400                 out = self.send_tcp(messages, channel)
401         else:
402             # do not use lock, http is synchronous
403             out = self.send_http(messages, channel)
404
405         return out
406
407     def resend_subscriptions(self):
408         for channel, messages in self.subscriptions.items():
409             if messages:
410                 self.send(messages, channel)
411
412
413
414     def parse_proxy_options(self, s):
415         if type(s) == type({}): return s  # fixme: type should be fixed
416         if type(s) != type(""): return None  
417         if s.lower() == 'none': return None
418         proxy = { "mode":"socks5", "host":"localhost" }
419         args = s.split(':')
420         n = 0
421         if proxy_modes.count(args[n]) == 1:
422             proxy["mode"] = args[n]
423             n += 1
424         if len(args) > n:
425             proxy["host"] = args[n]
426             n += 1
427         if len(args) > n:
428             proxy["port"] = args[n]
429         else:
430             proxy["port"] = "8080" if proxy["mode"] == "http" else "1080"
431         return proxy
432
433
434     def set_server(self, server, proxy=None):
435         # raise an error if the format isnt correct
436         a,b,c = server.split(':')
437         b = int(b)
438         assert c in 'stgh'
439         # set the server
440         if server != self.server or proxy != self.proxy:
441             print "changing server:", server, proxy
442             self.server = server
443             self.proxy = proxy
444             if self.protocol in 'st':
445                 self.s.shutdown(socket.SHUT_RDWR)
446                 self.s.close()
447             self.is_connected = False  # this exits the polling loop
448             self.trigger_callback('disconnecting') # for actively disconnecting
449
450     def is_empty(self, channel):
451         q = self.responses.get(channel)
452         if q: 
453             return q.empty()
454         else:
455             return True
456
457
458     def get_pending_requests(self, channel):
459         result = []
460         with self.lock:
461             for k, v in self.unanswered_requests.items():
462                 a, b, c = v
463                 if c == channel: result.append(k)
464         return result
465
466     def is_up_to_date(self, channel):
467         return self.is_empty(channel) and not self.get_pending_requests(channel)
468
469
470     def synchronous_get(self, requests, timeout=100000000):
471         # todo: use generators, unanswered_requests should be a list of arrays...
472         ids = self.send(requests)
473         id2 = ids[:]
474         res = {}
475         while ids:
476             r = self.responses['default'].get(True, timeout)
477             _id = r.get('id')
478             if _id in ids:
479                 ids.remove(_id)
480                 res[_id] = r.get('result')
481         out = []
482         for _id in id2:
483             out.append(res[_id])
484         return out
485
486
487     def start(self):
488         threading.Thread.start(self)
489         # wait until connection is established
490         self.connect_event.wait()
491
492     def run(self):
493         while True:
494             self.init_interface()
495             if self.is_connected:
496                 self.resend_subscriptions()
497                 self.run_tcp() if self.protocol in 'st' else self.run_http()
498
499             self.trigger_callback('disconnected')
500
501             if not self.loop: break
502             time.sleep(5)
503
504
505