backends/bitcoind/blockchain_processor.py

   1 import ast
   2 import hashlib
   3 from json import dumps, loads
   4 import leveldb
   5 import os
   6 from Queue import Queue
   7 import random
   8 import sys
   9 import time
  10 import threading
  11 import traceback
  12 import urllib
  13
  14 from backends.bitcoind import deserialize
  15 from processor import Processor, print_log
  16 from utils import *
  17
  18
  19 class BlockchainProcessor(Processor):
  20
  21     def __init__(self, config, shared):
  22         Processor.__init__(self)
  23
  24         self.shared = shared
  25         self.config = config
  26         self.up_to_date = False
  27         self.watched_addresses = []
  28         self.history_cache = {}
  29         self.chunk_cache = {}
  30         self.cache_lock = threading.Lock()
  31         self.headers_data = ''
  32
  33         self.mempool_addresses = {}
  34         self.mempool_hist = {}
  35         self.mempool_hashes = []
  36         self.mempool_lock = threading.Lock()
  37
  38         self.address_queue = Queue()
  39         self.dbpath = config.get('leveldb', 'path')
  40         self.pruning_limit = config.getint('leveldb', 'pruning_limit')
  41         self.db_version = 1 # increase this when database needs to be updated
  42
  43         self.dblock = threading.Lock()
  44         try:
  45             self.db = leveldb.LevelDB(self.dbpath)
  46         except:
  47             traceback.print_exc(file=sys.stdout)
  48             self.shared.stop()
  49
  50         self.bitcoind_url = 'http://%s:%s@%s:%s/' % (
  51             config.get('bitcoind', 'user'),
  52             config.get('bitcoind', 'password'),
  53             config.get('bitcoind', 'host'),
  54             config.get('bitcoind', 'port'))
  55
  56         self.height = 0
  57         self.is_test = False
  58         self.sent_height = 0
  59         self.sent_header = None
  60
  61         try:
  62             hist = self.deserialize(self.db.Get('height'))
  63             self.last_hash, self.height, db_version = hist[0]
  64             print_log("Database version", self.db_version)
  65             print_log("Blockchain height", self.height)
  66         except:
  67             traceback.print_exc(file=sys.stdout)
  68             print_log('initializing database')
  69             self.height = 0
  70             self.last_hash = '000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f'
  71             db_version = self.db_version
  72
  73         # check version
  74         if self.db_version != db_version:
  75             print_log("Your database '%s' is deprecated. Please create a new database"%self.dbpath)
  76             self.shared.stop()
  77             return
  78
  79         # catch_up headers
  80         self.init_headers(self.height)
  81
  82         threading.Timer(0, lambda: self.catch_up(sync=False)).start()
  83         while not shared.stopped() and not self.up_to_date:
  84             try:
  85                 time.sleep(1)
  86             except:
  87                 print "keyboard interrupt: stopping threads"
  88                 shared.stop()
  89                 sys.exit(0)
  90
  91         print_log("blockchain is up to date.")
  92
  93         threading.Timer(10, self.main_iteration).start()
  94
  95     def bitcoind(self, method, params=[]):
  96         postdata = dumps({"method": method, 'params': params, 'id': 'jsonrpc'})
  97         try:
  98             respdata = urllib.urlopen(self.bitcoind_url, postdata).read()
  99         except:
 100             traceback.print_exc(file=sys.stdout)
 101             self.shared.stop()
 102
 103         r = loads(respdata)
 104         if r['error'] is not None:
 105             raise BaseException(r['error'])
 106         return r.get('result')
 107
 108     def serialize(self, h):
 109         s = ''
 110         for txid, txpos, height in h:
 111             s += self.serialize_item(txid, txpos, height)
 112         return s
 113
 114     def serialize_item(self, txid, txpos, height, spent=chr(0)):
 115         s = (txid + int_to_hex(txpos, 4) + int_to_hex(height, 3)).decode('hex') + spent
 116         return s
 117
 118     def deserialize_item(self,s):
 119         txid = s[0:32].encode('hex')
 120         txpos = int(rev_hex(s[32:36].encode('hex')), 16)
 121         height = int(rev_hex(s[36:39].encode('hex')), 16)
 122         spent = s[39:40]
 123         return (txid, txpos, height, spent)
 124
 125     def deserialize(self, s):
 126         h = []
 127         while s:
 128             txid, txpos, height, spent = self.deserialize_item(s[0:40])
 129             h.append((txid, txpos, height))
 130             if spent == chr(1):
 131                 txid, txpos, height, spent = self.deserialize_item(s[40:80])
 132                 h.append((txid, txpos, height))
 133             s = s[80:]
 134         return h
 135
 136     def block2header(self, b):
 137         return {
 138             "block_height": b.get('height'),
 139             "version": b.get('version'),
 140             "prev_block_hash": b.get('previousblockhash'),
 141             "merkle_root": b.get('merkleroot'),
 142             "timestamp": b.get('time'),
 143             "bits": int(b.get('bits'), 16),
 144             "nonce": b.get('nonce'),
 145         }
 146
 147     def get_header(self, height):
 148         block_hash = self.bitcoind('getblockhash', [height])
 149         b = self.bitcoind('getblock', [block_hash])
 150         return self.block2header(b)
 151
 152     def init_headers(self, db_height):
 153         self.chunk_cache = {}
 154         self.headers_filename = os.path.join(self.dbpath, 'blockchain_headers')
 155
 156         if os.path.exists(self.headers_filename):
 157             height = os.path.getsize(self.headers_filename)/80 - 1   # the current height
 158             if height > 0:
 159                 prev_hash = self.hash_header(self.read_header(height))
 160             else:
 161                 prev_hash = None
 162         else:
 163             open(self.headers_filename, 'wb').close()
 164             prev_hash = None
 165             height = -1
 166
 167         if height < db_height:
 168             print_log("catching up missing headers:", height, db_height)
 169
 170         try:
 171             while height < db_height:
 172                 height = height + 1
 173                 header = self.get_header(height)
 174                 if height > 1:
 175                     assert prev_hash == header.get('prev_block_hash')
 176                 self.write_header(header, sync=False)
 177                 prev_hash = self.hash_header(header)
 178                 if (height % 1000) == 0:
 179                     print_log("headers file:", height)
 180         except KeyboardInterrupt:
 181             self.flush_headers()
 182             sys.exit()
 183
 184         self.flush_headers()
 185
 186     def hash_header(self, header):
 187         return rev_hex(Hash(header_to_string(header).decode('hex')).encode('hex'))
 188
 189     def read_header(self, block_height):
 190         if os.path.exists(self.headers_filename):
 191             with open(self.headers_filename, 'rb') as f:
 192                 f.seek(block_height * 80)
 193                 h = f.read(80)
 194             if len(h) == 80:
 195                 h = header_from_string(h)
 196                 return h
 197
 198     def read_chunk(self, index):
 199         with open(self.headers_filename, 'rb') as f:
 200             f.seek(index*2016*80)
 201             chunk = f.read(2016*80)
 202         return chunk.encode('hex')
 203
 204     def write_header(self, header, sync=True):
 205         if not self.headers_data:
 206             self.headers_offset = header.get('block_height')
 207
 208         self.headers_data += header_to_string(header).decode('hex')
 209         if sync or len(self.headers_data) > 40*100:
 210             self.flush_headers()
 211
 212         with self.cache_lock:
 213             chunk_index = header.get('block_height')/2016
 214             if self.chunk_cache.get(chunk_index):
 215                 self.chunk_cache.pop(chunk_index)
 216
 217     def pop_header(self):
 218         # we need to do this only if we have not flushed
 219         if self.headers_data:
 220             self.headers_data = self.headers_data[:-40]
 221
 222     def flush_headers(self):
 223         if not self.headers_data:
 224             return
 225         with open(self.headers_filename, 'rb+') as f:
 226             f.seek(self.headers_offset*80)
 227             f.write(self.headers_data)
 228         self.headers_data = ''
 229
 230     def get_chunk(self, i):
 231         # store them on disk; store the current chunk in memory
 232         with self.cache_lock:
 233             chunk = self.chunk_cache.get(i)
 234             if not chunk:
 235                 chunk = self.read_chunk(i)
 236                 self.chunk_cache[i] = chunk
 237
 238         return chunk
 239
 240     def get_mempool_transaction(self, txid):
 241         try:
 242             raw_tx = self.bitcoind('getrawtransaction', [txid, 0, -1])
 243         except:
 244             return None
 245
 246         vds = deserialize.BCDataStream()
 247         vds.write(raw_tx.decode('hex'))
 248
 249         return deserialize.parse_Transaction(vds, is_coinbase=False)
 250
 251     def get_history(self, addr, cache_only=False):
 252         with self.cache_lock:
 253             hist = self.history_cache.get(addr)
 254         if hist is not None:
 255             return hist
 256         if cache_only:
 257             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         # sort history, because redeeming transactions are next to the corresponding txout
 268         hist.sort(key=lambda tup: tup[2])
 269
 270         # add memory pool
 271         with self.mempool_lock:
 272             for txid in self.mempool_hist.get(addr, []):
 273                 hist.append((txid, 0, 0))
 274
 275         # uniqueness
 276         hist = set(map(lambda x: (x[0], x[2]), hist))
 277
 278         # convert to dict
 279         hist = map(lambda x: {'tx_hash': x[0], 'height': x[1]}, hist)
 280
 281         # add something to distinguish between unused and empty addresses
 282         if hist == [] and is_known:
 283             hist = ['*']
 284
 285         with self.cache_lock:
 286             self.history_cache[addr] = hist
 287         return hist
 288
 289     def get_status(self, addr, cache_only=False):
 290         tx_points = self.get_history(addr, cache_only)
 291         if cache_only and tx_points == -1:
 292             return -1
 293
 294         if not tx_points:
 295             return None
 296         if tx_points == ['*']:
 297             return '*'
 298         status = ''
 299         for tx in tx_points:
 300             status += tx.get('tx_hash') + ':%d:' % tx.get('height')
 301         return hashlib.sha256(status).digest().encode('hex')
 302
 303     def get_merkle(self, tx_hash, height):
 304
 305         block_hash = self.bitcoind('getblockhash', [height])
 306         b = self.bitcoind('getblock', [block_hash])
 307         tx_list = b.get('tx')
 308         tx_pos = tx_list.index(tx_hash)
 309
 310         merkle = map(hash_decode, tx_list)
 311         target_hash = hash_decode(tx_hash)
 312         s = []
 313         while len(merkle) != 1:
 314             if len(merkle) % 2:
 315                 merkle.append(merkle[-1])
 316             n = []
 317             while merkle:
 318                 new_hash = Hash(merkle[0] + merkle[1])
 319                 if merkle[0] == target_hash:
 320                     s.append(hash_encode(merkle[1]))
 321                     target_hash = new_hash
 322                 elif merkle[1] == target_hash:
 323                     s.append(hash_encode(merkle[0]))
 324                     target_hash = new_hash
 325                 n.append(new_hash)
 326                 merkle = merkle[2:]
 327             merkle = n
 328
 329         return {"block_height": height, "merkle": s, "pos": tx_pos}
 330
 331
 332     def add_to_history(self, addr, tx_hash, tx_pos, tx_height):
 333         # keep it sorted
 334         s = self.serialize_item(tx_hash, tx_pos, tx_height) + 40*chr(0)
 335         assert len(s) == 80
 336
 337         serialized_hist = self.batch_list[addr]
 338
 339         l = len(serialized_hist)/80
 340         for i in range(l-1, -1, -1):
 341             item = serialized_hist[80*i:80*(i+1)]
 342             item_height = int(rev_hex(item[36:39].encode('hex')), 16)
 343             if item_height < tx_height:
 344                 serialized_hist = serialized_hist[0:80*(i+1)] + s + serialized_hist[80*(i+1):]
 345                 break
 346         else:
 347             serialized_hist = s + serialized_hist
 348
 349         self.batch_list[addr] = serialized_hist
 350
 351         # backlink
 352         txo = (tx_hash + int_to_hex(tx_pos, 4)).decode('hex')
 353         self.batch_txio[txo] = addr
 354
 355
 356
 357     def revert_add_to_history(self, addr, tx_hash, tx_pos, tx_height):
 358
 359         serialized_hist = self.batch_list[addr]
 360         s = self.serialize_item(tx_hash, tx_pos, tx_height) + 40*chr(0)
 361         if serialized_hist.find(s) == -1: raise
 362         serialized_hist = serialized_hist.replace(s, '')
 363         self.batch_list[addr] = serialized_hist
 364
 365
 366
 367     def prune_history(self, addr, undo):
 368         # remove items that have bit set to one
 369         if undo.get(addr) is None: undo[addr] = []
 370
 371         serialized_hist = self.batch_list[addr]
 372         l = len(serialized_hist)/80
 373         for i in range(l):
 374             if len(serialized_hist)/80 < self.pruning_limit: break
 375             item = serialized_hist[80*i:80*(i+1)]
 376             if item[39:40] == chr(1):
 377                 assert item[79:80] == chr(2)
 378                 serialized_hist = serialized_hist[0:80*i] + serialized_hist[80*(i+1):]
 379                 undo[addr].append(item)  # items are ordered
 380         self.batch_list[addr] = serialized_hist
 381
 382
 383     def revert_prune_history(self, addr, undo):
 384         # restore removed items
 385         serialized_hist = self.batch_list[addr]
 386
 387         if undo.get(addr) is not None:
 388             itemlist = undo.pop(addr)
 389         else:
 390             return
 391
 392         if not itemlist: return
 393
 394         l = len(serialized_hist)/80
 395         tx_item = ''
 396         for i in range(l-1, -1, -1):
 397             if tx_item == '':
 398                 if not itemlist:
 399                     break
 400                 else:
 401                     tx_item = itemlist.pop(-1) # get the last element
 402                     tx_height = int(rev_hex(tx_item[36:39].encode('hex')), 16)
 403
 404             item = serialized_hist[80*i:80*(i+1)]
 405             item_height = int(rev_hex(item[36:39].encode('hex')), 16)
 406
 407             if item_height < tx_height:
 408                 serialized_hist = serialized_hist[0:80*(i+1)] + tx_item + serialized_hist[80*(i+1):]
 409                 tx_item = ''
 410
 411         else:
 412             serialized_hist = ''.join(itemlist) + tx_item + serialized_hist
 413
 414         self.batch_list[addr] = serialized_hist
 415
 416
 417     def set_spent_bit(self, addr, txi, is_spent, txid=None, index=None, height=None):
 418         serialized_hist = self.batch_list[addr]
 419         l = len(serialized_hist)/80
 420         for i in range(l):
 421             item = serialized_hist[80*i:80*(i+1)]
 422             if item[0:36] == txi:
 423                 if is_spent:
 424                     new_item = item[0:39] + chr(1) + self.serialize_item(txid, index, height, chr(2))
 425                 else:
 426                     new_item = item[0:39] + chr(0) + chr(0)*40
 427                 serialized_hist = serialized_hist[0:80*i] + new_item + serialized_hist[80*(i+1):]
 428                 break
 429         else:
 430             hist = self.deserialize(serialized_hist)
 431             raise BaseException("prevout not found", addr, hist, txi.encode('hex'))
 432
 433         self.batch_list[addr] = serialized_hist
 434
 435
 436     def unset_spent_bit(self, addr, txi):
 437         self.set_spent_bit(addr, txi, False)
 438         self.batch_txio[txi] = addr
 439
 440
 441     def deserialize_block(self, block):
 442         txlist = block.get('tx')
 443         tx_hashes = []  # ordered txids
 444         txdict = {}     # deserialized tx
 445         is_coinbase = True
 446         for raw_tx in txlist:
 447             tx_hash = hash_encode(Hash(raw_tx.decode('hex')))
 448             tx_hashes.append(tx_hash)
 449             vds = deserialize.BCDataStream()
 450             vds.write(raw_tx.decode('hex'))
 451             tx = deserialize.parse_Transaction(vds, is_coinbase)
 452             txdict[tx_hash] = tx
 453             is_coinbase = False
 454         return tx_hashes, txdict
 455
 456     def get_undo_info(self, height):
 457         s = self.db.Get("undo%d" % (height % 100))
 458         return eval(s)
 459
 460     def write_undo_info(self, batch, height, undo_info):
 461         if self.is_test or height > self.bitcoind_height - 100:
 462             batch.Put("undo%d" % (height % 100), repr(undo_info))
 463
 464     def import_block(self, block, block_hash, block_height, sync, revert=False):
 465
 466         self.batch_list = {}  # address -> history
 467         self.batch_txio = {}  # transaction i/o -> address
 468
 469         block_inputs = []
 470         block_outputs = []
 471         addr_to_read = []
 472
 473         # deserialize transactions
 474         t0 = time.time()
 475         tx_hashes, txdict = self.deserialize_block(block)
 476
 477         t00 = time.time()
 478
 479         # undo info
 480         if revert:
 481             undo_info = self.get_undo_info(block_height)
 482         else:
 483             undo_info = {}
 484
 485
 486         if not revert:
 487             # read addresses of tx inputs
 488             for tx in txdict.values():
 489                 for x in tx.get('inputs'):
 490                     txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 491                     block_inputs.append(txi)
 492
 493             block_inputs.sort()
 494             for txi in block_inputs:
 495                 try:
 496                     addr = self.db.Get(txi)
 497                 except:
 498                     # print "addr not in db", txi.encode('hex')
 499                     # the input could come from the same block
 500                     continue
 501                 self.batch_txio[txi] = addr
 502                 addr_to_read.append(addr)
 503
 504         else:
 505             for txid, tx in txdict.items():
 506                 for x in tx.get('outputs'):
 507                     txo = (txid + int_to_hex(x.get('index'), 4)).decode('hex')
 508                     block_outputs.append(txo)
 509                     addr_to_read.append( x.get('address') )
 510
 511                 undo = undo_info.get(txid)
 512                 for i, x in enumerate(tx.get('inputs')):
 513                     addr = undo['prev_addr'][i]
 514                     addr_to_read.append(addr)
 515
 516
 517
 518
 519
 520         # read histories of addresses
 521         for txid, tx in txdict.items():
 522             for x in tx.get('outputs'):
 523                 addr_to_read.append(x.get('address'))
 524
 525         addr_to_read.sort()
 526         for addr in addr_to_read:
 527             try:
 528                 self.batch_list[addr] = self.db.Get(addr)
 529             except:
 530                 self.batch_list[addr] = ''
 531
 532
 533         # process
 534         t1 = time.time()
 535
 536         if revert:
 537             tx_hashes = tx_hashes[::-1]
 538
 539
 540         for txid in tx_hashes:  # must be ordered
 541             tx = txdict[txid]
 542             if not revert:
 543
 544                 undo = { 'prev_addr':[] } # contains the list of pruned items for each address in the tx; also, 'prev_addr' is a list of prev addresses
 545
 546                 prev_addr = []
 547                 for i, x in enumerate(tx.get('inputs')):
 548                     txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 549                     addr = self.batch_txio[txi]
 550
 551                     # add redeem item to the history.
 552                     # add it right next to the input txi? this will break history sorting, but it's ok if I neglect tx inputs during search
 553                     self.set_spent_bit(addr, txi, True, txid, i, block_height)
 554
 555                     # when I prune, prune a pair
 556                     self.prune_history(addr, undo)
 557                     prev_addr.append(addr)
 558
 559                 undo['prev_addr'] = prev_addr
 560
 561                 # here I add only the outputs to history; maybe I want to add inputs too (that's in the other loop)
 562                 for x in tx.get('outputs'):
 563                     addr = x.get('address')
 564                     self.add_to_history(addr, txid, x.get('index'), block_height)
 565                     self.prune_history(addr, undo)  # prune here because we increased the length of the history
 566
 567                 undo_info[txid] = undo
 568
 569             else:
 570
 571                 undo = undo_info.pop(txid)
 572
 573                 for x in tx.get('outputs'):
 574                     addr = x.get('address')
 575                     self.revert_prune_history(addr, undo)
 576                     self.revert_add_to_history(addr, txid, x.get('index'), block_height)
 577
 578                 prev_addr = undo.pop('prev_addr')
 579                 for i, x in enumerate(tx.get('inputs')):
 580                     addr = prev_addr[i]
 581                     self.revert_prune_history(addr, undo)
 582                     txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 583                     self.unset_spent_bit(addr, txi)
 584
 585                 assert undo == {}
 586
 587         if revert:
 588             assert undo_info == {}
 589
 590
 591         # write
 592         max_len = 0
 593         max_addr = ''
 594         t2 = time.time()
 595
 596         batch = leveldb.WriteBatch()
 597         for addr, serialized_hist in self.batch_list.items():
 598             batch.Put(addr, serialized_hist)
 599             l = len(serialized_hist)/80
 600             if l > max_len:
 601                 max_len = l
 602                 max_addr = addr
 603
 604         if not revert:
 605             # add new created outputs
 606             for txio, addr in self.batch_txio.items():
 607                 batch.Put(txio, addr)
 608             # delete spent inputs
 609             for txi in block_inputs:
 610                 batch.Delete(txi)
 611             # add undo info
 612             self.write_undo_info(batch, block_height, undo_info)
 613         else:
 614             # restore spent inputs
 615             for txio, addr in self.batch_txio.items():
 616                 # print "restoring spent input", repr(txio)
 617                 batch.Put(txio, addr)
 618             # delete spent outputs
 619             for txo in block_outputs:
 620                 batch.Delete(txo)
 621
 622         # add the max
 623         batch.Put('height', self.serialize([(block_hash, block_height, self.db_version)]))
 624
 625         # actual write
 626         self.db.Write(batch, sync=sync)
 627
 628         t3 = time.time()
 629         if t3 - t0 > 10 and not sync:
 630             print_log("block", block_height,
 631                       "parse:%0.2f " % (t00 - t0),
 632                       "read:%0.2f " % (t1 - t00),
 633                       "proc:%.2f " % (t2-t1),
 634                       "write:%.2f " % (t3-t2),
 635                       "max:", max_len, max_addr)
 636
 637         for addr in self.batch_list.keys():
 638             self.invalidate_cache(addr)
 639
 640     def add_request(self, request):
 641         # see if we can get if from cache. if not, add to queue
 642         if self.process(request, cache_only=True) == -1:
 643             self.queue.put(request)
 644
 645     def process(self, request, cache_only=False):
 646         #print "abe process", request
 647
 648         message_id = request['id']
 649         method = request['method']
 650         params = request.get('params', [])
 651         result = None
 652         error = None
 653
 654         if method == 'blockchain.numblocks.subscribe':
 655             result = self.height
 656
 657         elif method == 'blockchain.headers.subscribe':
 658             result = self.header
 659
 660         elif method == 'blockchain.address.subscribe':
 661             try:
 662                 address = params[0]
 663                 result = self.get_status(address, cache_only)
 664                 self.watch_address(address)
 665             except BaseException, e:
 666                 error = str(e) + ': ' + address
 667                 print_log("error:", error)
 668
 669         elif method == 'blockchain.address.unsubscribe':
 670             try:
 671                 password = params[0]
 672                 address = params[1]
 673                 if password == self.config.get('server', 'password'):
 674                     self.watched_addresses.remove(address)
 675                     # print_log('unsubscribed', address)
 676                     result = "ok"
 677                 else:
 678                     print_log('incorrect password')
 679                     result = "authentication error"
 680             except BaseException, e:
 681                 error = str(e) + ': ' + address
 682                 print_log("error:", error)
 683
 684         elif method == 'blockchain.address.get_history':
 685             try:
 686                 address = params[0]
 687                 result = self.get_history(address, cache_only)
 688             except BaseException, e:
 689                 error = str(e) + ': ' + address
 690                 print_log("error:", error)
 691
 692         elif method == 'blockchain.block.get_header':
 693             if cache_only:
 694                 result = -1
 695             else:
 696                 try:
 697                     height = params[0]
 698                     result = self.get_header(height)
 699                 except BaseException, e:
 700                     error = str(e) + ': %d' % height
 701                     print_log("error:", error)
 702
 703         elif method == 'blockchain.block.get_chunk':
 704             if cache_only:
 705                 result = -1
 706             else:
 707                 try:
 708                     index = params[0]
 709                     result = self.get_chunk(index)
 710                 except BaseException, e:
 711                     error = str(e) + ': %d' % index
 712                     print_log("error:", error)
 713
 714         elif method == 'blockchain.transaction.broadcast':
 715             try:
 716                 txo = self.bitcoind('sendrawtransaction', params)
 717                 print_log("sent tx:", txo)
 718                 result = txo
 719             except BaseException, e:
 720                 result = str(e)  # do not send an error
 721                 print_log("error:", result, params)
 722
 723         elif method == 'blockchain.transaction.get_merkle':
 724             if cache_only:
 725                 result = -1
 726             else:
 727                 try:
 728                     tx_hash = params[0]
 729                     tx_height = params[1]
 730                     result = self.get_merkle(tx_hash, tx_height)
 731                 except BaseException, e:
 732                     error = str(e) + ': ' + repr(params)
 733                     print_log("get_merkle error:", error)
 734
 735         elif method == 'blockchain.transaction.get':
 736             try:
 737                 tx_hash = params[0]
 738                 height = params[1]
 739                 result = self.bitcoind('getrawtransaction', [tx_hash, 0, height])
 740             except BaseException, e:
 741                 error = str(e) + ': ' + repr(params)
 742                 print_log("tx get error:", error)
 743
 744         else:
 745             error = "unknown method:%s" % method
 746
 747         if cache_only and result == -1:
 748             return -1
 749
 750         if error:
 751             self.push_response({'id': message_id, 'error': error})
 752         elif result != '':
 753             self.push_response({'id': message_id, 'result': result})
 754
 755     def watch_address(self, addr):
 756         if addr not in self.watched_addresses:
 757             self.watched_addresses.append(addr)
 758
 759     def catch_up(self, sync=True):
 760         t1 = time.time()
 761
 762         while not self.shared.stopped():
 763             # are we done yet?
 764             info = self.bitcoind('getinfo')
 765             self.bitcoind_height = info.get('blocks')
 766             bitcoind_block_hash = self.bitcoind('getblockhash', [self.bitcoind_height])
 767             if self.last_hash == bitcoind_block_hash:
 768                 self.up_to_date = True
 769                 break
 770
 771             # not done..
 772             self.up_to_date = False
 773             next_block_hash = self.bitcoind('getblockhash', [self.height + 1])
 774             next_block = self.bitcoind('getblock', [next_block_hash, 1])
 775
 776             # fixme: this is unsafe, if we revert when the undo info is not yet written
 777             revert = (random.randint(1, 100) == 1) if self.is_test else False
 778
 779             if (next_block.get('previousblockhash') == self.last_hash) and not revert:
 780
 781                 self.import_block(next_block, next_block_hash, self.height+1, sync)
 782                 self.height = self.height + 1
 783                 self.write_header(self.block2header(next_block), sync)
 784                 self.last_hash = next_block_hash
 785
 786                 if self.height % 100 == 0 and not sync:
 787                     t2 = time.time()
 788                     print_log("catch_up: block %d (%.3fs)" % (self.height, t2 - t1))
 789                     t1 = t2
 790
 791             else:
 792                 # revert current block
 793                 block = self.bitcoind('getblock', [self.last_hash, 1])
 794                 print_log("blockchain reorg", self.height, block.get('previousblockhash'), self.last_hash)
 795                 self.import_block(block, self.last_hash, self.height, sync, revert=True)
 796                 self.pop_header()
 797                 self.flush_headers()
 798
 799                 self.height -= 1
 800
 801                 # read previous header from disk
 802                 self.header = self.read_header(self.height)
 803                 self.last_hash = self.hash_header(self.header)
 804
 805         self.header = self.block2header(self.bitcoind('getblock', [self.last_hash]))
 806
 807     def memorypool_update(self):
 808         mempool_hashes = self.bitcoind('getrawmempool')
 809
 810         for tx_hash in mempool_hashes:
 811             if tx_hash in self.mempool_hashes:
 812                 continue
 813
 814             tx = self.get_mempool_transaction(tx_hash)
 815             if not tx:
 816                 continue
 817
 818             for x in tx.get('inputs'):
 819                 txi = (x.get('prevout_hash') + int_to_hex(x.get('prevout_n'), 4)).decode('hex')
 820                 try:
 821                     addr = self.db.Get(txi)
 822                 except:
 823                     continue
 824                 l = self.mempool_addresses.get(tx_hash, [])
 825                 if addr not in l:
 826                     l.append(addr)
 827                     self.mempool_addresses[tx_hash] = l
 828
 829             for x in tx.get('outputs'):
 830                 addr = x.get('address')
 831                 l = self.mempool_addresses.get(tx_hash, [])
 832                 if addr not in l:
 833                     l.append(addr)
 834                     self.mempool_addresses[tx_hash] = l
 835
 836             self.mempool_hashes.append(tx_hash)
 837
 838         # remove older entries from mempool_hashes
 839         self.mempool_hashes = mempool_hashes
 840
 841         # remove deprecated entries from mempool_addresses
 842         for tx_hash, addresses in self.mempool_addresses.items():
 843             if tx_hash not in self.mempool_hashes:
 844                 self.mempool_addresses.pop(tx_hash)
 845
 846         # rebuild mempool histories
 847         new_mempool_hist = {}
 848         for tx_hash, addresses in self.mempool_addresses.items():
 849             for addr in addresses:
 850                 h = new_mempool_hist.get(addr, [])
 851                 if tx_hash not in h:
 852                     h.append(tx_hash)
 853                 new_mempool_hist[addr] = h
 854
 855         # invalidate cache for mempool addresses whose mempool history has changed
 856         new_mempool_hist_keys = new_mempool_hist.keys()
 857         self_mempool_hist_keys = self.mempool_hist.keys()
 858
 859         for addr in new_mempool_hist_keys:
 860             if addr in self_mempool_hist_keys:
 861                 if self.mempool_hist[addr] != new_mempool_hist[addr]:
 862                     self.invalidate_cache(addr)
 863             else:
 864                 self.invalidate_cache(addr)
 865
 866         # invalidate cache for addresses that are removed from mempool ?
 867         # this should not be necessary if they go into a block, but they might not
 868         for addr in self_mempool_hist_keys:
 869             if addr not in new_mempool_hist_keys:
 870                 self.invalidate_cache(addr)
 871
 872
 873         with self.mempool_lock:
 874             self.mempool_hist = new_mempool_hist
 875
 876     def invalidate_cache(self, address):
 877         with self.cache_lock:
 878             if address in self.history_cache:
 879                 print_log("cache: invalidating", address)
 880                 self.history_cache.pop(address)
 881
 882         if address in self.watched_addresses:
 883             self.address_queue.put(address)
 884
 885     def main_iteration(self):
 886         if self.shared.stopped():
 887             print_log("blockchain processor terminating")
 888             return
 889
 890         with self.dblock:
 891             t1 = time.time()
 892             self.catch_up()
 893             t2 = time.time()
 894
 895         self.memorypool_update()
 896         t3 = time.time()
 897         # print "mempool:", len(self.mempool_addresses), len(self.mempool_hist), "%.3fs"%(t3 - t2)
 898
 899         if self.sent_height != self.height:
 900             self.sent_height = self.height
 901             self.push_response({
 902                 'id': None,
 903                 'method': 'blockchain.numblocks.subscribe',
 904                 'params': [self.height],
 905             })
 906
 907         if self.sent_header != self.header:
 908             print_log("blockchain: %d (%.3fs)" % (self.height, t2 - t1))
 909             self.sent_header = self.header
 910             self.push_response({
 911                 'id': None,
 912                 'method': 'blockchain.headers.subscribe',
 913                 'params': [self.header],
 914             })
 915
 916         while True:
 917             try:
 918                 addr = self.address_queue.get(False)
 919             except:
 920                 break
 921             if addr in self.watched_addresses:
 922                 status = self.get_status(addr)
 923                 self.push_response({
 924                     'id': None,
 925                     'method': 'blockchain.address.subscribe',
 926                     'params': [addr, status],
 927                 })
 928
 929         if not self.shared.stopped():
 930             threading.Timer(10, self.main_iteration).start()
 931         else:
 932             print_log("blockchain processor terminating")