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, addr, tx_hash, tx_pos):
 351
 352         txi = (tx_hash + int_to_hex(tx_pos, 4)).decode('hex')
 353
 354         if addr is None:
 355             try:
 356                 addr = self.batch_txio[txi]
 357             except:
 358                 raise BaseException(tx_hash, tx_pos)
 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             hist = self.deserialize(serialized_hist)
 371             raise BaseException("prevout not found", addr, hist, tx_hash, tx_pos)
 372
 373         self.batch_list[addr] = serialized_hist
 374         return height, addr
 375
 376
 377     def deserialize_block(self, block):
 378         txlist = block.get('tx')
 379         tx_hashes = []  # ordered txids
 380         txdict = {}     # deserialized tx
 381         is_coinbase = True
 382         for raw_tx in txlist:
 383             tx_hash = hash_encode(Hash(raw_tx.decode('hex')))
 384             tx_hashes.append(tx_hash)
 385             vds = deserialize.BCDataStream()
 386             vds.write(raw_tx.decode('hex'))
 387             tx = deserialize.parse_Transaction(vds, is_coinbase)
 388             txdict[tx_hash] = tx
 389             is_coinbase = False
 390         return tx_hashes, txdict
 391
 392     def get_undo_info(self, height):
 393         s = self.db.Get("undo%d"%(height%100))
 394         return eval(s)
 395
 396     def write_undo_info(self, batch, height, undo_info):
 397         if self.is_test or height > self.bitcoind_height - 100:
 398             batch.Put("undo%d"%(height%100), repr(undo_info))
 399
 400
 401     def import_block(self, block, block_hash, block_height, sync, revert=False):
 402
 403         self.batch_list = {}  # address -> history
 404         self.batch_txio = {}  # transaction i/o -> address
 405
 406         block_inputs = []
 407         block_outputs = []
 408         addr_to_read = []
 409
 410         # deserialize transactions
 411         t0 = time.time()
 412         tx_hashes, txdict = self.deserialize_block(block)
 413
 414         t00 = time.time()
 415
 416
 417         if not revert:
 418             # read addresses of tx inputs
 419             for tx in txdict.values():
 420                 for x in tx.get('inputs'):
 421                     txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 422                     block_inputs.append(txi)
 423
 424             block_inputs.sort()
 425             for txi in block_inputs:
 426                 try:
 427                     addr = self.db.Get(txi)
 428                 except:
 429                     # the input could come from the same block
 430                     continue
 431                 self.batch_txio[txi] = addr
 432                 addr_to_read.append(addr)
 433
 434         else:
 435             for txid, tx in txdict.items():
 436                 for x in tx.get('outputs'):
 437                     txo = (txid + int_to_hex(x.get('index'), 4)).decode('hex')
 438                     block_outputs.append(txo)
 439
 440
 441
 442         # read histories of addresses
 443         for txid, tx in txdict.items():
 444             for x in tx.get('outputs'):
 445                 addr_to_read.append(x.get('address'))
 446
 447         addr_to_read.sort()
 448         for addr in addr_to_read:
 449             try:
 450                 self.batch_list[addr] = self.db.Get(addr)
 451             except:
 452                 self.batch_list[addr] = ''
 453
 454
 455         if revert:
 456             undo_info = self.get_undo_info(block_height)
 457             print "undo", block_height, undo_info
 458         else: undo_info = {}
 459
 460         # process
 461         t1 = time.time()
 462
 463         if revert: tx_hashes = tx_hashes[::-1]
 464         for txid in tx_hashes: # must be ordered
 465             tx = txdict[txid]
 466             if not revert:
 467
 468                 undo = []
 469                 for x in tx.get('inputs'):
 470                     prevout_height, prevout_addr = self.remove_from_history( None, x.get('prevout_hash'), x.get('prevout_n'))
 471                     undo.append( (prevout_height, prevout_addr) )
 472                 undo_info[txid] = undo
 473
 474                 for x in tx.get('outputs'):
 475                     self.add_to_history( x.get('address'), txid, x.get('index'), block_height)
 476
 477             else:
 478                 for x in tx.get('outputs'):
 479                     self.remove_from_history( x.get('address'), txid, x.get('index'))
 480
 481                 i = 0
 482                 for x in tx.get('inputs'):
 483                     prevout_height, prevout_addr = undo_info.get(txid)[i]
 484                     i += 1
 485
 486                     # read the history into batch list
 487                     if self.batch_list.get(prevout_addr) is None:
 488                         self.batch_list[prevout_addr] = self.db.Get(prevout_addr)
 489
 490                     # re-add them to the history
 491                     self.add_to_history( prevout_addr, x.get('prevout_hash'), x.get('prevout_n'), prevout_height)
 492                     print "new hist for", prevout_addr, self.deserialize(self.batch_list[prevout_addr])
 493
 494         # write
 495         max_len = 0
 496         max_addr = ''
 497         t2 = time.time()
 498
 499         batch = leveldb.WriteBatch()
 500         for addr, serialized_hist in self.batch_list.items():
 501             batch.Put(addr, serialized_hist)
 502             l = len(serialized_hist)
 503             if l > max_len:
 504                 max_len = l
 505                 max_addr = addr
 506
 507         if not revert:
 508             # add new created outputs
 509             for txio, addr in self.batch_txio.items():
 510                 batch.Put(txio, addr)
 511             # delete spent inputs
 512             for txi in block_inputs:
 513                 batch.Delete(txi)
 514             # add undo info
 515             self.write_undo_info(batch, block_height, undo_info)
 516         else:
 517             # restore spent inputs
 518             for txio, addr in self.batch_txio.items():
 519                 batch.Put(txio, addr)
 520             # delete spent outputs
 521             for txo in block_outputs:
 522                 batch.Delete(txo)
 523
 524
 525         # add the max
 526         batch.Put('height', self.serialize( [(block_hash, block_height, 0)] ) )
 527
 528         # actual write
 529         self.db.Write(batch, sync = sync)
 530
 531         t3 = time.time()
 532         if t3 - t0 > 10 and not sync:
 533             print_log("block", block_height,
 534                       "parse:%0.2f "%(t00 - t0),
 535                       "read:%0.2f "%(t1 - t00),
 536                       "proc:%.2f "%(t2-t1),
 537                       "write:%.2f "%(t3-t2),
 538                       "max:", max_len, max_addr)
 539
 540         for addr in self.batch_list.keys(): self.invalidate_cache(addr)
 541
 542
 543
 544     def add_request(self, request):
 545         # see if we can get if from cache. if not, add to queue
 546         if self.process( request, cache_only = True) == -1:
 547             self.queue.put(request)
 548
 549
 550
 551     def process(self, request, cache_only = False):
 552         #print "abe process", request
 553
 554         message_id = request['id']
 555         method = request['method']
 556         params = request.get('params',[])
 557         result = None
 558         error = None
 559
 560         if method == 'blockchain.numblocks.subscribe':
 561             result = self.height
 562
 563         elif method == 'blockchain.headers.subscribe':
 564             result = self.header
 565
 566         elif method == 'blockchain.address.subscribe':
 567             try:
 568                 address = params[0]
 569                 result = self.get_status(address, cache_only)
 570                 self.watch_address(address)
 571             except BaseException, e:
 572                 error = str(e) + ': ' + address
 573                 print_log( "error:", error )
 574
 575         elif method == 'blockchain.address.subscribe2':
 576             try:
 577                 address = params[0]
 578                 result = self.get_status(address, cache_only)
 579                 self.watch_address(address)
 580             except BaseException, e:
 581                 error = str(e) + ': ' + address
 582                 print_log( "error:", error )
 583
 584         elif method == 'blockchain.address.get_history2':
 585             try:
 586                 address = params[0]
 587                 result = self.get_history( address, cache_only )
 588             except BaseException, e:
 589                 error = str(e) + ': ' + address
 590                 print_log( "error:", error )
 591
 592         elif method == 'blockchain.block.get_header':
 593             if cache_only:
 594                 result = -1
 595             else:
 596                 try:
 597                     height = params[0]
 598                     result = self.get_header( height )
 599                 except BaseException, e:
 600                     error = str(e) + ': %d'% height
 601                     print_log( "error:", error )
 602
 603         elif method == 'blockchain.block.get_chunk':
 604             if cache_only:
 605                 result = -1
 606             else:
 607                 try:
 608                     index = params[0]
 609                     result = self.get_chunk( index )
 610                 except BaseException, e:
 611                     error = str(e) + ': %d'% index
 612                     print_log( "error:", error)
 613
 614         elif method == 'blockchain.transaction.broadcast':
 615             txo = self.bitcoind('sendrawtransaction', params)
 616             print_log( "sent tx:", txo )
 617             result = txo
 618
 619         elif method == 'blockchain.transaction.get_merkle':
 620             if cache_only:
 621                 result = -1
 622             else:
 623                 try:
 624                     tx_hash = params[0]
 625                     tx_height = params[1]
 626                     result = self.get_merkle(tx_hash, tx_height)
 627                 except BaseException, e:
 628                     error = str(e) + ': ' + tx_hash
 629                     print_log( "error:", error )
 630
 631         elif method == 'blockchain.transaction.get':
 632             try:
 633                 tx_hash = params[0]
 634                 height = params[1]
 635                 result = self.bitcoind('getrawtransaction', [tx_hash, 0, height] )
 636             except BaseException, e:
 637                 error = str(e) + ': ' + tx_hash
 638                 print_log( "error:", error )
 639
 640         else:
 641             error = "unknown method:%s"%method
 642
 643         if cache_only and result == -1: return -1
 644
 645         if error:
 646             response = { 'id':message_id, 'error':error }
 647             self.push_response(response)
 648         elif result != '':
 649             response = { 'id':message_id, 'result':result }
 650             self.push_response(response)
 651
 652
 653     def watch_address(self, addr):
 654         if addr not in self.watched_addresses:
 655             self.watched_addresses.append(addr)
 656
 657
 658
 659     def catch_up(self, sync = True):
 660
 661         t1 = time.time()
 662
 663         while not self.shared.stopped():
 664
 665             # are we done yet?
 666             info = self.bitcoind('getinfo')
 667             self.bitcoind_height = info.get('blocks')
 668             bitcoind_block_hash = self.bitcoind('getblockhash', [self.bitcoind_height])
 669             if self.last_hash == bitcoind_block_hash:
 670                 self.up_to_date = True
 671                 break
 672
 673             # not done..
 674             self.up_to_date = False
 675             next_block_hash = self.bitcoind('getblockhash', [self.height+1])
 676             next_block = self.bitcoind('getblock', [next_block_hash, 1])
 677
 678             revert = (random.randint(1, 10)==1) if self.is_test else False
 679             if (next_block.get('previousblockhash') == self.last_hash) and not revert:
 680
 681                 self.import_block(next_block, next_block_hash, self.height+1, sync)
 682                 self.height = self.height + 1
 683                 self.write_header(self.block2header(next_block), sync)
 684                 self.last_hash = next_block_hash
 685
 686                 if (self.height)%100 == 0 and not sync:
 687                     t2 = time.time()
 688                     print_log( "catch_up: block %d (%.3fs)"%( self.height, t2 - t1 ) )
 689                     t1 = t2
 690
 691             else:
 692                 # revert current block
 693                 block = self.bitcoind('getblock', [self.last_hash, 1])
 694                 print_log( "blockchain reorg", self.height, block.get('previousblockhash'), self.last_hash )
 695                 self.import_block(block, self.last_hash, self.height, sync, revert=True)
 696                 self.pop_header()
 697                 self.flush_headers()
 698
 699                 self.height = self.height -1
 700
 701                 # read previous header from disk
 702                 self.header = self.read_header(self.height)
 703                 self.last_hash = self.hash_header(self.header)
 704
 705
 706         self.header = self.block2header(self.bitcoind('getblock', [self.last_hash]))
 707
 708
 709
 710
 711     def memorypool_update(self):
 712
 713         mempool_hashes = self.bitcoind('getrawmempool')
 714
 715         for tx_hash in mempool_hashes:
 716             if tx_hash in self.mempool_hashes: continue
 717
 718             tx = self.get_transaction(tx_hash)
 719             if not tx: continue
 720
 721             for x in tx.get('inputs'):
 722                 txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 723                 try:
 724                     addr = self.db.Get(txi)
 725                 except:
 726                     continue
 727                 l = self.mempool_addresses.get(tx_hash, [])
 728                 if addr not in l:
 729                     l.append( addr )
 730                     self.mempool_addresses[tx_hash] = l
 731
 732             for x in tx.get('outputs'):
 733                 addr = x.get('address')
 734                 l = self.mempool_addresses.get(tx_hash, [])
 735                 if addr not in l:
 736                     l.append( addr )
 737                     self.mempool_addresses[tx_hash] = l
 738
 739             self.mempool_hashes.append(tx_hash)
 740
 741         # remove older entries from mempool_hashes
 742         self.mempool_hashes = mempool_hashes
 743
 744         # remove deprecated entries from mempool_addresses
 745         for tx_hash, addresses in self.mempool_addresses.items():
 746             if tx_hash not in self.mempool_hashes:
 747                 self.mempool_addresses.pop(tx_hash)
 748
 749         # rebuild histories
 750         new_mempool_hist = {}
 751         for tx_hash, addresses in self.mempool_addresses.items():
 752             for addr in addresses:
 753                 h = new_mempool_hist.get(addr, [])
 754                 if tx_hash not in h:
 755                     h.append( tx_hash )
 756                 new_mempool_hist[addr] = h
 757
 758         for addr in new_mempool_hist.keys():
 759             if addr in self.mempool_hist.keys():
 760                 if self.mempool_hist[addr] != new_mempool_hist[addr]:
 761                     self.invalidate_cache(addr)
 762             else:
 763                 self.invalidate_cache(addr)
 764
 765         with self.mempool_lock:
 766             self.mempool_hist = new_mempool_hist
 767
 768
 769
 770     def invalidate_cache(self, address):
 771         with self.cache_lock:
 772             if self.history_cache.has_key(address):
 773                 print_log( "cache: invalidating", address )
 774                 self.history_cache.pop(address)
 775
 776         if address in self.watched_addresses:
 777             self.address_queue.put(address)
 778
 779
 780
 781     def main_iteration(self):
 782
 783         if self.shared.stopped():
 784             print_log( "blockchain processor terminating" )
 785             return
 786
 787         with self.dblock:
 788             t1 = time.time()
 789             self.catch_up()
 790             t2 = time.time()
 791
 792         self.memorypool_update()
 793         t3 = time.time()
 794         # print "mempool:", len(self.mempool_addresses), len(self.mempool_hist), "%.3fs"%(t3 - t2)
 795
 796
 797         if self.sent_height != self.height:
 798             self.sent_height = self.height
 799             self.push_response({ 'id': None, 'method':'blockchain.numblocks.subscribe', 'params':[self.height] })
 800
 801         if self.sent_header != self.header:
 802             print_log( "blockchain: %d (%.3fs)"%( self.height, t2 - t1 ) )
 803             self.sent_header = self.header
 804             self.push_response({ 'id': None, 'method':'blockchain.headers.subscribe', 'params':[self.header] })
 805
 806         while True:
 807             try:
 808                 addr = self.address_queue.get(False)
 809             except:
 810                 break
 811             if addr in self.watched_addresses:
 812                 status = self.get_status( addr )
 813                 self.push_response({ 'id': None, 'method':'blockchain.address.subscribe', 'params':[addr, status] })
 814                 self.push_response({ 'id': None, 'method':'blockchain.address.subscribe2', 'params':[addr, status] })
 815
 816
 817         if not self.shared.stopped():
 818             threading.Timer(10, self.main_iteration).start()
 819         else:
 820             print_log( "blockchain processor terminating" )
 821
 822
 823
 824