store limited undo information for reorgs
[electrum-server.git] / backends / bitcoind / blockchain_processor.py
1 from json import dumps, loads
2 import leveldb, urllib
3 import deserialize
4 import ast, time, threading, hashlib
5 from Queue import Queue
6 import traceback, sys, os, random
7
8
9
10 Hash = lambda x: hashlib.sha256(hashlib.sha256(x).digest()).digest()
11 hash_encode = lambda x: x[::-1].encode('hex')
12 hash_decode = lambda x: x.decode('hex')[::-1]
13
14
15
16 def rev_hex(s):
17     return s.decode('hex')[::-1].encode('hex')
18
19
20 def int_to_hex(i, length=1):
21     s = hex(i)[2:].rstrip('L')
22     s = "0"*(2*length - len(s)) + s
23     return rev_hex(s)
24
25 def header_to_string(res):
26     pbh = res.get('prev_block_hash')
27     if pbh is None: pbh = '0'*64
28     s = int_to_hex(res.get('version'),4) \
29         + rev_hex(pbh) \
30         + rev_hex(res.get('merkle_root')) \
31         + int_to_hex(int(res.get('timestamp')),4) \
32         + int_to_hex(int(res.get('bits')),4) \
33         + int_to_hex(int(res.get('nonce')),4)
34     return s
35
36 def header_from_string( s):
37     hex_to_int = lambda s: eval('0x' + s[::-1].encode('hex'))
38     h = {}
39     h['version'] = hex_to_int(s[0:4])
40     h['prev_block_hash'] = hash_encode(s[4:36])
41     h['merkle_root'] = hash_encode(s[36:68])
42     h['timestamp'] = hex_to_int(s[68:72])
43     h['bits'] = hex_to_int(s[72:76])
44     h['nonce'] = hex_to_int(s[76:80])
45     return h
46
47
48
49
50 from processor import Processor, print_log
51
52 class BlockchainProcessor(Processor):
53
54     def __init__(self, config, shared):
55         Processor.__init__(self)
56
57         self.shared = shared
58         self.up_to_date = False
59         self.watched_addresses = []
60         self.history_cache = {}
61         self.chunk_cache = {}
62         self.cache_lock = threading.Lock()
63         self.headers_data = ''
64
65         self.mempool_addresses = {}
66         self.mempool_hist = {}
67         self.mempool_hashes = []
68         self.mempool_lock = threading.Lock()
69
70         self.address_queue = Queue()
71         self.dbpath = config.get('leveldb', 'path')
72
73         self.dblock = threading.Lock()
74         try:
75             self.db = leveldb.LevelDB(self.dbpath)
76         except:
77             traceback.print_exc(file=sys.stdout)
78             self.shared.stop()
79
80         self.bitcoind_url = 'http://%s:%s@%s:%s/' % (
81             config.get('bitcoind','user'),
82             config.get('bitcoind','password'),
83             config.get('bitcoind','host'),
84             config.get('bitcoind','port'))
85
86         self.height = 0
87         self.is_test = False
88         self.sent_height = 0
89         self.sent_header = None
90
91
92         try:
93             hist = self.deserialize(self.db.Get('height'))
94             self.last_hash, self.height, _ = hist[0] 
95             print_log( "hist", hist )
96         except:
97             #traceback.print_exc(file=sys.stdout)
98             print_log('initializing database')
99             self.height = 0
100             self.last_hash = '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
101
102         # catch_up headers
103         self.init_headers(self.height)
104
105         threading.Timer(0, lambda: self.catch_up(sync=False)).start()
106         while not shared.stopped() and not self.up_to_date:
107             try:
108                 time.sleep(1)
109             except:
110                 print "keyboard interrupt: stopping threads"
111                 shared.stop()
112                 sys.exit(0)
113
114         print_log( "blockchain is up to date." )
115
116         threading.Timer(10, self.main_iteration).start()
117
118
119
120     def bitcoind(self, method, params=[]):
121         postdata = dumps({"method": method, 'params': params, 'id':'jsonrpc'})
122         respdata = urllib.urlopen(self.bitcoind_url, postdata).read()
123         r = loads(respdata)
124         if r['error'] != None:
125             raise BaseException(r['error'])
126         return r.get('result')
127     
128
129     def serialize(self, h):
130         s = ''
131         for txid, txpos, height in h:
132             s += txid + int_to_hex(txpos, 4) + int_to_hex(height, 4)
133         return s.decode('hex')
134
135
136     def deserialize(self, s):
137         h = []
138         while s:
139             txid = s[0:32].encode('hex')
140             txpos = int( rev_hex( s[32:36].encode('hex') ), 16 )
141             height = int( rev_hex( s[36:40].encode('hex') ), 16 )
142             h.append( ( txid, txpos, height ) )
143             s = s[40:]
144         return h
145
146
147     def block2header(self, b):
148         return {"block_height":b.get('height'), "version":b.get('version'), "prev_block_hash":b.get('previousblockhash'), 
149                 "merkle_root":b.get('merkleroot'), "timestamp":b.get('time'), "bits":int(b.get('bits'),16), "nonce":b.get('nonce')}
150
151
152     def get_header(self, height):
153         block_hash = self.bitcoind('getblockhash', [height])
154         b = self.bitcoind('getblock', [block_hash])
155         return self.block2header(b)
156     
157
158     def init_headers(self, db_height):
159         self.chunk_cache = {}
160         self.headers_filename = os.path.join( self.dbpath, 'blockchain_headers')
161
162         if os.path.exists(self.headers_filename):
163             height = os.path.getsize(self.headers_filename)/80 - 1   # the current height
164             if height > 0:
165                 prev_hash = self.hash_header(self.read_header(height))
166             else:
167                 prev_hash = None
168         else:
169             open(self.headers_filename,'wb').close()
170             prev_hash = None
171             height = -1
172
173         if height < db_height:
174             print_log( "catching up missing headers:", height, db_height)
175
176         try:
177             while height != db_height:
178                 height = height + 1
179                 header = self.get_header(height)
180                 if height>1: 
181                     assert prev_hash == header.get('prev_block_hash')
182                 self.write_header(header, sync=False)
183                 prev_hash = self.hash_header(header)
184                 if height%1000==0: print_log("headers file:",height)
185         except KeyboardInterrupt:
186             self.flush_headers()
187             sys.exit()
188
189         self.flush_headers()
190
191
192     def hash_header(self, header):
193         return rev_hex(Hash(header_to_string(header).decode('hex')).encode('hex'))
194
195
196     def read_header(self, block_height):
197         if os.path.exists(self.headers_filename):
198             f = open(self.headers_filename,'rb')
199             f.seek(block_height*80)
200             h = f.read(80)
201             f.close()
202             if len(h) == 80:
203                 h = header_from_string(h)
204                 return h
205
206
207     def read_chunk(self, index):
208         f = open(self.headers_filename,'rb')
209         f.seek(index*2016*80)
210         chunk = f.read(2016*80)
211         f.close()
212         return chunk.encode('hex')
213
214
215     def write_header(self, header, sync=True):
216         if not self.headers_data:
217             self.headers_offset = header.get('block_height')
218
219         self.headers_data += header_to_string(header).decode('hex')
220         if sync or len(self.headers_data) > 40*100:
221             self.flush_headers()
222
223     def pop_header(self):
224         # we need to do this only if we have not flushed
225         if self.headers_data:
226             self.headers_data = self.headers_data[:-40]
227
228     def flush_headers(self):
229         if not self.headers_data: return
230         f = open(self.headers_filename,'rb+')
231         f.seek(self.headers_offset*80)
232         f.write(self.headers_data)
233         f.close()
234         self.headers_data = ''
235
236
237     def get_chunk(self, i):
238         # store them on disk; store the current chunk in memory
239         chunk = self.chunk_cache.get(i)
240         if not chunk:
241             chunk = self.read_chunk(i)
242             self.chunk_cache[i] = chunk
243         return chunk
244
245
246     def get_transaction(self, txid, block_height=-1, is_coinbase = False):
247         raw_tx = self.bitcoind('getrawtransaction', [txid, 0, block_height])
248         vds = deserialize.BCDataStream()
249         vds.write(raw_tx.decode('hex'))
250         out = deserialize.parse_Transaction(vds, is_coinbase)
251         return out
252
253
254     def get_history(self, addr, cache_only=False):
255         with self.cache_lock: hist = self.history_cache.get( addr )
256         if hist is not None: return hist
257         if cache_only: return -1
258
259         with self.dblock:
260             try:
261                 hist = self.deserialize(self.db.Get(addr))
262                 is_known = True
263             except: 
264                 hist = []
265                 is_known = False
266
267         # should not be necessary
268         hist.sort( key=lambda tup: tup[1])
269         # check uniqueness too...
270
271         # add memory pool
272         with self.mempool_lock:
273             for txid in self.mempool_hist.get(addr,[]):
274                 hist.append((txid, 0, 0))
275
276         hist = map(lambda x: {'tx_hash':x[0], 'height':x[2]}, hist)
277         # add something to distinguish between unused and empty addresses
278         if hist == [] and is_known: hist = ['*']
279
280         with self.cache_lock: self.history_cache[addr] = hist
281         return hist
282
283
284     def get_status(self, addr, cache_only=False):
285         tx_points = self.get_history(addr, cache_only)
286         if cache_only and tx_points == -1: return -1
287
288         if not tx_points: return None
289         if tx_points == ['*']: return '*'
290         status = ''
291         for tx in tx_points:
292             status += tx.get('tx_hash') + ':%d:' % tx.get('height')
293         return hashlib.sha256( status ).digest().encode('hex')
294
295
296     def get_merkle(self, tx_hash, height):
297
298         block_hash = self.bitcoind('getblockhash', [height])
299         b = self.bitcoind('getblock', [block_hash])
300         tx_list = b.get('tx')
301         tx_pos = tx_list.index(tx_hash)
302         
303         merkle = map(hash_decode, tx_list)
304         target_hash = hash_decode(tx_hash)
305         s = []
306         while len(merkle) != 1:
307             if len(merkle)%2: merkle.append( merkle[-1] )
308             n = []
309             while merkle:
310                 new_hash = Hash( merkle[0] + merkle[1] )
311                 if merkle[0] == target_hash:
312                     s.append( hash_encode( merkle[1]))
313                     target_hash = new_hash
314                 elif merkle[1] == target_hash:
315                     s.append( hash_encode( merkle[0]))
316                     target_hash = new_hash
317                 n.append( new_hash )
318                 merkle = merkle[2:]
319             merkle = n
320
321         return {"block_height":height, "merkle":s, "pos":tx_pos}
322
323         
324
325
326     def add_to_history(self, addr, tx_hash, tx_pos, tx_height):
327
328         # keep it sorted
329         s = (tx_hash + int_to_hex(tx_pos, 4) + int_to_hex(tx_height, 4)).decode('hex')
330
331         serialized_hist = self.batch_list[addr] 
332
333         l = len(serialized_hist)/40
334         for i in range(l-1, -1, -1):
335             item = serialized_hist[40*i:40*(i+1)]
336             item_height = int( rev_hex( item[36:40].encode('hex') ), 16 )
337             if item_height < tx_height:
338                 serialized_hist = serialized_hist[0:40*(i+1)] + s + serialized_hist[40*(i+1):]
339                 break
340         else:
341             serialized_hist = s + serialized_hist
342
343         self.batch_list[addr] = serialized_hist
344
345         # backlink
346         txo = (tx_hash + int_to_hex(tx_pos, 4)).decode('hex')
347         self.batch_txio[txo] = addr
348
349
350     def remove_from_history(self, tx_hash, tx_pos):
351                     
352         txi = (tx_hash + int_to_hex(tx_pos, 4)).decode('hex')
353         try:
354             addr = self.batch_txio[txi]
355         except:
356             raise BaseException(tx_hash, tx_pos)
357             print "WARNING: cannot find address for", (tx_hash, tx_pos)
358             return
359
360         serialized_hist = self.batch_list[addr]
361
362         l = len(serialized_hist)/40
363         for i in range(l):
364             item = serialized_hist[40*i:40*(i+1)]
365             if item[0:36] == txi:
366                 height = int( rev_hex( item[36:40].encode('hex') ), 16 )
367                 serialized_hist = serialized_hist[0:40*i] + serialized_hist[40*(i+1):]
368                 break
369         else:
370             raise BaseException("prevout not found", addr, hist, tx_hash, tx_pos)
371
372         self.batch_list[addr] = serialized_hist
373         return height, addr
374
375
376     def deserialize_block(self, block):
377         txlist = block.get('tx')
378         tx_hashes = []  # ordered txids
379         txdict = {}     # deserialized tx
380         is_coinbase = True
381         for raw_tx in txlist:
382             tx_hash = hash_encode(Hash(raw_tx.decode('hex')))
383             tx_hashes.append(tx_hash)
384             vds = deserialize.BCDataStream()
385             vds.write(raw_tx.decode('hex'))
386             tx = deserialize.parse_Transaction(vds, is_coinbase)
387             txdict[tx_hash] = tx
388             is_coinbase = False
389         return tx_hashes, txdict
390
391     def get_undo_info(self, height):
392         s = self.db.Get("undo%d"%(height%100))
393         return eval(s)
394
395     def write_undo_info(self, batch, height, undo_info):
396         batch.Put("undo%d"%(height%100), repr(undo_info))
397
398
399     def import_block(self, block, block_hash, block_height, sync, revert=False):
400
401         self.batch_list = {}  # address -> history
402         self.batch_txio = {}  # transaction i/o -> address
403
404         inputs_to_read = []
405         addr_to_read = []
406
407         # deserialize transactions
408         t0 = time.time()
409         tx_hashes, txdict = self.deserialize_block(block)
410
411         t00 = time.time()
412
413         if revert:
414             # read addresses of tx outputs
415             for tx_hash, tx in txdict.items():
416                 for x in tx.get('outputs'):
417                     txo = (tx_hash + int_to_hex(x.get('index'), 4)).decode('hex')
418                 self.batch_txio[txo] = x.get('address')
419         else:
420             # read addresses of tx inputs
421             for tx in txdict.values():
422                 for x in tx.get('inputs'):
423                     txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
424                     inputs_to_read.append(txi)
425
426             inputs_to_read.sort()
427             for txi in inputs_to_read:
428                 try:
429                     addr = self.db.Get(txi)
430                 except:
431                     # the input could come from the same block
432                     continue
433                 self.batch_txio[txi] = addr
434                 addr_to_read.append(addr)
435
436
437         # read histories of addresses
438         for txid, tx in txdict.items():
439             for x in tx.get('outputs'):
440                 addr_to_read.append(x.get('address'))
441
442         addr_to_read.sort()
443         for addr in addr_to_read:
444             try:
445                 self.batch_list[addr] = self.db.Get(addr)
446             except: 
447                 self.batch_list[addr] = ''
448
449
450         if revert: 
451             undo_info = self.get_undo_info(block_height)
452             print "undo", block_height, undo_info
453         else: undo_info = {}
454
455         # process
456         t1 = time.time()
457
458         for txid in tx_hashes: # must be ordered
459             tx = txdict[txid]
460             if not revert:
461
462                 undo = []
463                 for x in tx.get('inputs'):
464                     prevout_height, prevout_addr = self.remove_from_history( x.get('prevout_hash'), x.get('prevout_n'))
465                     undo.append( (prevout_height, prevout_addr) )
466                 undo_info[txid] = undo
467
468                 for x in tx.get('outputs'):
469                     self.add_to_history( x.get('address'), txid, x.get('index'), block_height)
470                     
471             else:
472                 for x in tx.get('outputs'):
473                     self.remove_from_history( txid, x.get('index'))
474
475                 i = 0
476                 for x in tx.get('inputs'):
477                     prevout_height, prevout_addr = undo_info.get(txid)[i]
478                     i += 1
479
480                     # read the history into batch list
481                     self.batch_list[prevout_addr] = self.db.Get(prevout_addr)
482                     # re-add them to the history
483                     self.add_to_history( prevout_addr, x.get('prevout_hash'), x.get('prevout_n'), prevout_height)
484                     print "new hist", self.deserialize(self.batch_list[prevout_addr])
485
486         # write
487         max_len = 0
488         max_addr = ''
489         t2 = time.time()
490
491         batch = leveldb.WriteBatch()
492         for addr, serialized_hist in self.batch_list.items():
493             batch.Put(addr, serialized_hist)
494             l = len(serialized_hist)
495             if l > max_len:
496                 max_len = l
497                 max_addr = addr
498
499         for txio, addr in self.batch_txio.items():
500             batch.Put(txio, addr)
501         # delete spent inputs
502         for txi in inputs_to_read:
503             batch.Delete(txi)
504
505         # add undo info 
506         if not revert: self.write_undo_info(batch, block_height, undo_info)
507
508         # add the max
509         batch.Put('height', self.serialize( [(block_hash, block_height, 0)] ) )
510
511         # actual write
512         self.db.Write(batch, sync = sync)
513
514         t3 = time.time()
515         if t3 - t0 > 10 and not sync: 
516             print_log("block", block_height, 
517                       "parse:%0.2f "%(t00 - t0), 
518                       "read:%0.2f "%(t1 - t00), 
519                       "proc:%.2f "%(t2-t1), 
520                       "write:%.2f "%(t3-t2), 
521                       "max:", max_len, max_addr)
522
523         for addr in self.batch_list.keys(): self.invalidate_cache(addr)
524
525
526
527     def add_request(self, request):
528         # see if we can get if from cache. if not, add to queue
529         if self.process( request, cache_only = True) == -1:
530             self.queue.put(request)
531
532
533
534     def process(self, request, cache_only = False):
535         #print "abe process", request
536
537         message_id = request['id']
538         method = request['method']
539         params = request.get('params',[])
540         result = None
541         error = None
542
543         if method == 'blockchain.numblocks.subscribe':
544             result = self.height
545
546         elif method == 'blockchain.headers.subscribe':
547             result = self.header
548
549         elif method == 'blockchain.address.subscribe':
550             try:
551                 address = params[0]
552                 result = self.get_status(address, cache_only)
553                 self.watch_address(address)
554             except BaseException, e:
555                 error = str(e) + ': ' + address
556                 print_log( "error:", error )
557
558         elif method == 'blockchain.address.subscribe2':
559             try:
560                 address = params[0]
561                 result = self.get_status(address, cache_only)
562                 self.watch_address(address)
563             except BaseException, e:
564                 error = str(e) + ': ' + address
565                 print_log( "error:", error )
566
567         elif method == 'blockchain.address.get_history2':
568             try:
569                 address = params[0]
570                 result = self.get_history( address, cache_only )
571             except BaseException, e:
572                 error = str(e) + ': ' + address
573                 print_log( "error:", error )
574
575         elif method == 'blockchain.block.get_header':
576             if cache_only: 
577                 result = -1
578             else:
579                 try:
580                     height = params[0]
581                     result = self.get_header( height ) 
582                 except BaseException, e:
583                     error = str(e) + ': %d'% height
584                     print_log( "error:", error )
585                     
586         elif method == 'blockchain.block.get_chunk':
587             if cache_only:
588                 result = -1
589             else:
590                 try:
591                     index = params[0]
592                     result = self.get_chunk( index ) 
593                 except BaseException, e:
594                     error = str(e) + ': %d'% index
595                     print_log( "error:", error)
596
597         elif method == 'blockchain.transaction.broadcast':
598             txo = self.bitcoind('sendrawtransaction', params)
599             print_log( "sent tx:", txo )
600             result = txo 
601
602         elif method == 'blockchain.transaction.get_merkle':
603             if cache_only:
604                 result = -1
605             else:
606                 try:
607                     tx_hash = params[0]
608                     tx_height = params[1]
609                     result = self.get_merkle(tx_hash, tx_height) 
610                 except BaseException, e:
611                     error = str(e) + ': ' + tx_hash
612                     print_log( "error:", error )
613                     
614         elif method == 'blockchain.transaction.get':
615             try:
616                 tx_hash = params[0]
617                 height = params[1]
618                 result = self.bitcoind('getrawtransaction', [tx_hash, 0, height] ) 
619             except BaseException, e:
620                 error = str(e) + ': ' + tx_hash
621                 print_log( "error:", error )
622
623         else:
624             error = "unknown method:%s"%method
625
626         if cache_only and result == -1: return -1
627
628         if error:
629             response = { 'id':message_id, 'error':error }
630             self.push_response(response)
631         elif result != '':
632             response = { 'id':message_id, 'result':result }
633             self.push_response(response)
634
635
636     def watch_address(self, addr):
637         if addr not in self.watched_addresses:
638             self.watched_addresses.append(addr)
639
640
641
642     def catch_up(self, sync = True):
643
644         t1 = time.time()
645
646         while not self.shared.stopped():
647
648             # are we done yet?
649             info = self.bitcoind('getinfo')
650             bitcoind_height = info.get('blocks')
651             bitcoind_block_hash = self.bitcoind('getblockhash', [bitcoind_height])
652             if self.last_hash == bitcoind_block_hash: 
653                 self.up_to_date = True
654                 break
655
656             # not done..
657             self.up_to_date = False
658             next_block_hash = self.bitcoind('getblockhash', [self.height+1])
659             next_block = self.bitcoind('getblock', [next_block_hash, 1])
660
661             revert = (random.randint(1, 1000)!=1) if self.is_test else False
662             if (next_block.get('previousblockhash') == self.last_hash) and not revert:
663
664                 self.import_block(next_block, next_block_hash, self.height+1, sync)
665                 self.height = self.height + 1
666                 self.write_header(self.block2header(next_block), sync)
667                 self.last_hash = next_block_hash
668
669                 if (self.height)%100 == 0 and not sync: 
670                     t2 = time.time()
671                     print_log( "catch_up: block %d (%.3fs)"%( self.height, t2 - t1 ) )
672                     t1 = t2
673                     
674             else:
675                 # revert current block
676                 block = self.bitcoind('getblock', [self.last_hash, 1])
677                 print_log( "blockchain reorg", self.height, block.get('previousblockhash'), self.last_hash )
678                 self.import_block(block, self.last_hash, self.height, sync, revert=True)
679                 self.pop_header()
680                 self.flush_headers()
681
682                 self.height = self.height -1
683
684                 # read previous header from disk
685                 self.header = self.read_header(self.height)
686                 self.last_hash = self.hash_header(self.header)
687         
688
689         self.header = self.block2header(self.bitcoind('getblock', [self.last_hash]))
690
691
692
693             
694     def memorypool_update(self):
695
696         mempool_hashes = self.bitcoind('getrawmempool')
697
698         for tx_hash in mempool_hashes:
699             if tx_hash in self.mempool_hashes: continue
700
701             tx = self.get_transaction(tx_hash)
702             if not tx: continue
703
704             for x in tx.get('inputs'):
705                 txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
706                 try:
707                     addr = self.db.Get(txi)    
708                 except:
709                     continue
710                 l = self.mempool_addresses.get(tx_hash, [])
711                 if addr not in l: 
712                     l.append( addr )
713                     self.mempool_addresses[tx_hash] = l
714
715             for x in tx.get('outputs'):
716                 addr = x.get('address')
717                 l = self.mempool_addresses.get(tx_hash, [])
718                 if addr not in l: 
719                     l.append( addr )
720                     self.mempool_addresses[tx_hash] = l
721
722             self.mempool_hashes.append(tx_hash)
723
724         # remove older entries from mempool_hashes
725         self.mempool_hashes = mempool_hashes
726
727         # remove deprecated entries from mempool_addresses
728         for tx_hash, addresses in self.mempool_addresses.items():
729             if tx_hash not in self.mempool_hashes:
730                 self.mempool_addresses.pop(tx_hash)
731
732         # rebuild histories
733         new_mempool_hist = {}
734         for tx_hash, addresses in self.mempool_addresses.items():
735             for addr in addresses:
736                 h = new_mempool_hist.get(addr, [])
737                 if tx_hash not in h: 
738                     h.append( tx_hash )
739                 new_mempool_hist[addr] = h
740
741         for addr in new_mempool_hist.keys():
742             if addr in self.mempool_hist.keys():
743                 if self.mempool_hist[addr] != new_mempool_hist[addr]: 
744                     self.invalidate_cache(addr)
745             else:
746                 self.invalidate_cache(addr)
747
748         with self.mempool_lock:
749             self.mempool_hist = new_mempool_hist
750
751
752
753     def invalidate_cache(self, address):
754         with self.cache_lock:
755             if self.history_cache.has_key(address):
756                 print_log( "cache: invalidating", address )
757                 self.history_cache.pop(address)
758
759         if address in self.watched_addresses:
760             self.address_queue.put(address)
761
762
763
764     def main_iteration(self):
765
766         if self.shared.stopped(): 
767             print_log( "blockchain processor terminating" )
768             return
769
770         with self.dblock:
771             t1 = time.time()
772             self.catch_up()
773             t2 = time.time()
774
775         self.memorypool_update()
776         t3 = time.time()
777         # print "mempool:", len(self.mempool_addresses), len(self.mempool_hist), "%.3fs"%(t3 - t2)
778
779
780         if self.sent_height != self.height:
781             self.sent_height = self.height
782             self.push_response({ 'id': None, 'method':'blockchain.numblocks.subscribe', 'params':[self.height] })
783
784         if self.sent_header != self.header:
785             print_log( "blockchain: %d (%.3fs)"%( self.height, t2 - t1 ) )
786             self.sent_header = self.header
787             self.push_response({ 'id': None, 'method':'blockchain.headers.subscribe', 'params':[self.header] })
788
789         while True:
790             try:
791                 addr = self.address_queue.get(False)
792             except:
793                 break
794             if addr in self.watched_addresses:
795                 status = self.get_status( addr )
796                 self.push_response({ 'id': None, 'method':'blockchain.address.subscribe', 'params':[addr, status] })
797                 self.push_response({ 'id': None, 'method':'blockchain.address.subscribe2', 'params':[addr, status] })
798
799
800         if not self.shared.stopped(): 
801             threading.Timer(10, self.main_iteration).start()
802         else:
803             print_log( "blockchain processor terminating" )
804
805
806
807