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, getwork
   5 from p2pool.util import deferral, forest, variable
   6
   7 class HeaderWrapper(object):
   8     target = 2**256 - 1
   9     __slots__ = 'hash previous_hash'.split(' ')
  10
  11     @classmethod
  12     def from_header(cls, header):
  13         return cls(bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header)), header['previous_block'])
  14
  15     def __init__(self, hash, previous_hash):
  16         self.hash, self.previous_hash = hash, previous_hash
  17
  18 class HeightTracker(object):
  19     '''Point this at a factory and let it take care of getting block heights'''
  20
  21     def __init__(self, rpc_proxy, factory, backlog_needed):
  22         self._rpc_proxy = rpc_proxy
  23         self._factory = factory
  24         self._backlog_needed = backlog_needed
  25
  26         self._tracker = forest.Tracker()
  27
  28         self._watch1 = self._factory.new_headers.watch(self._heard_headers)
  29         self._watch2 = self._factory.new_block.watch(self._request)
  30
  31         self._requested = set()
  32         self._clear_task = task.LoopingCall(self._requested.clear)
  33         self._clear_task.start(60)
  34
  35         self._last_notified_size = 0
  36
  37         self.updated = variable.Event()
  38
  39         self._think_task = task.LoopingCall(self._think)
  40         self._think_task.start(15)
  41         self._think2_task = task.LoopingCall(self._think2)
  42         self._think2_task.start(15)
  43         self.best_hash = None
  44
  45     def _think(self):
  46         try:
  47             highest_head = max(self._tracker.heads, key=lambda h: self._tracker.get_height_and_last(h)[0]) if self._tracker.heads else None
  48             if highest_head is None:
  49                 return # wait for think2
  50             height, last = self._tracker.get_height_and_last(highest_head)
  51             if height < self._backlog_needed:
  52                 self._request(last)
  53         except:
  54             log.err(None, 'Error in HeightTracker._think:')
  55
  56     @defer.inlineCallbacks
  57     def _think2(self):
  58         try:
  59             ba = getwork.BlockAttempt.from_getwork((yield self._rpc_proxy.rpc_getwork()))
  60             self._request(ba.previous_block)
  61             self.best_hash = ba.previous_block
  62         except:
  63             log.err(None, 'Error in HeightTracker._think2:')
  64
  65     def _heard_headers(self, headers):
  66         changed = False
  67         for header in headers:
  68             hw = HeaderWrapper.from_header(header)
  69             if hw.hash in self._tracker.shares:
  70                 continue
  71             changed = True
  72             self._tracker.add(hw)
  73         if changed:
  74             self.updated.happened()
  75         self._think()
  76
  77         if len(self._tracker.shares) >= self._last_notified_size + 100:
  78             print 'Have %i/%i block headers' % (len(self._tracker.shares), self._backlog_needed)
  79             self._last_notified_size = len(self._tracker.shares)
  80
  81     @defer.inlineCallbacks
  82     def _request(self, last):
  83         if last in self._tracker.shares:
  84             return
  85         if last in self._requested:
  86             return
  87         self._requested.add(last)
  88         (yield self._factory.getProtocol()).send_getheaders(version=1, have=[], last=last)
  89
  90     def get_height_rel_highest(self, block_hash):
  91         # callers: highest height can change during yields!
  92         best_height, best_last = self._tracker.get_height_and_last(self.best_hash)
  93         height, last = self._tracker.get_height_and_last(block_hash)
  94         if last != best_last:
  95             return -1000000000 # XXX hack
  96         return height - best_height
  97
  98 @defer.inlineCallbacks
  99 def get_height_rel_highest_func(bitcoind, factory, current_work, net):
 100     if '\ngetblock ' in (yield deferral.retry()(bitcoind.rpc_help)()):
 101         @deferral.DeferredCacher
 102         @defer.inlineCallbacks
 103         def height_cacher(block_hash):
 104             try:
 105                 x = yield bitcoind.rpc_getblock('%x' % (block_hash,))
 106             except jsonrpc.Error, e:
 107                 if e.code == -5 and not p2pool.DEBUG:
 108                     raise deferral.RetrySilentlyException()
 109                 raise
 110             defer.returnValue(x['blockcount'] if 'blockcount' in x else x['height'])
 111         best_height_cached = variable.Variable((yield deferral.retry()(height_cacher)(current_work.value['previous_block'])))
 112         def get_height_rel_highest(block_hash):
 113             this_height = height_cacher.call_now(block_hash, 0)
 114             best_height = height_cacher.call_now(current_work.value['previous_block'], 0)
 115             best_height_cached.set(max(best_height_cached.value, this_height, best_height))
 116             return this_height - best_height_cached.value
 117     else:
 118         get_height_rel_highest = HeightTracker(bitcoind, factory, 5*net.SHARE_PERIOD*net.CHAIN_LENGTH/net.PARENT.BLOCK_PERIOD).get_height_rel_highest
 119     defer.returnValue(get_height_rel_highest)