p2pool/bitcoin/height_tracker.py

   1 from twisted.internet import defer, task
   2 from twisted.python import log
   3
   4 from p2pool.bitcoin import data as bitcoin_data
   5 from p2pool.util import deferral, forest, jsonrpc, variable
   6
   7 class HeaderWrapper(object):
   8     __slots__ = 'hash previous_hash'.split(' ')
   9
  10     @classmethod
  11     def from_header(cls, header):
  12         return cls(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header['previous_block'])
  13
  14     def __init__(self, hash, previous_hash):
  15         self.hash, self.previous_hash = hash, previous_hash
  16
  17 class HeightTracker(object):
  18     '''Point this at a factory and let it take care of getting block heights'''
  19
  20     def __init__(self, best_block_func, factory, backlog_needed):
  21         self._best_block_func = best_block_func
  22         self._factory = factory
  23         self._backlog_needed = backlog_needed
  24
  25         self._tracker = forest.Tracker()
  26
  27         self._watch1 = self._factory.new_headers.watch(self._heard_headers)
  28         self._watch2 = self._factory.new_block.watch(self._request)
  29
  30         self._requested = set()
  31         self._clear_task = task.LoopingCall(self._requested.clear)
  32         self._clear_task.start(60)
  33
  34         self._last_notified_size = 0
  35
  36         self.updated = variable.Event()
  37
  38         self._think_task = task.LoopingCall(self._think)
  39         self._think_task.start(15)
  40         self._think2_task = task.LoopingCall(self._think2)
  41         self._think2_task.start(15)
  42
  43     def _think(self):
  44         try:
  45             highest_head = max(self._tracker.heads, key=lambda h: self._tracker.get_height_and_last(h)[0]) if self._tracker.heads else None
  46             if highest_head is None:
  47                 return # wait for think2
  48             height, last = self._tracker.get_height_and_last(highest_head)
  49             if height < self._backlog_needed:
  50                 self._request(last)
  51         except:
  52             log.err(None, 'Error in HeightTracker._think:')
  53
  54     def _think2(self):
  55         self._request(self._best_block_func())
  56
  57     def _heard_headers(self, headers):
  58         changed = False
  59         for header in headers:
  60             hw = HeaderWrapper.from_header(header)
  61             if hw.hash in self._tracker.shares:
  62                 continue
  63             changed = True
  64             self._tracker.add(hw)
  65         if changed:
  66             self.updated.happened()
  67         self._think()
  68
  69         if len(self._tracker.shares) >= self._last_notified_size + 100:
  70             print 'Have %i/%i block headers' % (len(self._tracker.shares), self._backlog_needed)
  71             self._last_notified_size = len(self._tracker.shares)
  72
  73     @defer.inlineCallbacks
  74     def _request(self, last):
  75         if last in self._tracker.shares:
  76             return
  77         if last in self._requested:
  78             return
  79         self._requested.add(last)
  80         (yield self._factory.getProtocol()).send_getheaders(version=1, have=[], last=last)
  81
  82     def get_height_rel_highest(self, block_hash):
  83         # callers: highest height can change during yields!
  84         best_height, best_last = self._tracker.get_height_and_last(self._best_block_func())
  85         height, last = self._tracker.get_height_and_last(block_hash)
  86         if last != best_last:
  87             return -1000000000 # XXX hack
  88         return height - best_height
  89
  90 @defer.inlineCallbacks
  91 def get_height_rel_highest_func(bitcoind, factory, best_block_func, net):
  92     if '\ngetblock ' in (yield deferral.retry()(bitcoind.rpc_help)()):
  93         @deferral.DeferredCacher
  94         @defer.inlineCallbacks
  95         def height_cacher(block_hash):
  96             try:
  97                 x = yield bitcoind.rpc_getblock('%x' % (block_hash,))
  98             except jsonrpc.Error, e:
  99                 if e.code == -5 and not p2pool.DEBUG:
 100                     raise deferral.RetrySilentlyException()
 101                 raise
 102             defer.returnValue(x['blockcount'] if 'blockcount' in x else x['height'])
 103         best_height_cached = variable.Variable((yield deferral.retry()(height_cacher)(best_block_func())))
 104         def get_height_rel_highest(block_hash):
 105             this_height = height_cacher.call_now(block_hash, 0)
 106             best_height = height_cacher.call_now(best_block_func(), 0)
 107             best_height_cached.set(max(best_height_cached.value, this_height, best_height))
 108             return this_height - best_height_cached.value
 109     else:
 110         get_height_rel_highest = HeightTracker(best_block_func, factory, 5*net.SHARE_PERIOD*net.CHAIN_LENGTH/net.PARENT.BLOCK_PERIOD).get_height_rel_highest
 111     defer.returnValue(get_height_rel_highest)