text: #!/usr/bin/env python3
  # Copyright (c) 2010 ArtForz -- public domain half-a-node
  # Copyright (c) 2012 Jeff Garzik
  # Copyright (c) 2010-2016 The LipCoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #
  # mininode.py - LipCoin P2P network half-a-node
  #
  # This python code was modified from ArtForz' public domain  half-a-node, as
  # found in the mini-node branch of http://github.com/jgarzik/pynode.
  #
  # NodeConn: an object which manages p2p connectivity to a lipcoin node
  # NodeConnCB: a base class that describes the interface for receiving
  #             callbacks with network messages from a NodeConn
  # CBlock, CTransaction, CBlockHeader, CTxIn, CTxOut, etc....:
  #     data structures that should map to corresponding structures in
  #     lipcoin/primitives
  # msg_block, msg_tx, msg_headers, etc.:
  #     data structures that represent network messages
  # ser_*, deser_*: functions that handle serialization/deserialization
  
  
  import struct
  import socket
  import asyncore
  import time
  import sys
  import random
  from .util import hex_str_to_bytes, bytes_to_hex_str
  from io import BytesIO
  from codecs import encode
  import hashlib
  from threading import RLock
  from threading import Thread
  import logging
  import copy
  from test_framework.siphash import siphash256
  
  BIP0031_VERSION = 60000
  MY_VERSION = 70014  # past bip-31 for ping/pong
  MY_SUBVERSION = b"/python-mininode-tester:0.0.3/"
  MY_RELAY = 1 # from version 70001 onwards, fRelay should be appended to version messages (BIP37)
  
  MAX_INV_SZ = 50000
  MAX_BLOCK_BASE_SIZE = 1000000
  
  COIN = 100000000 # 1 dgb in satoshis
  
  NODE_NETWORK = (1 << 0)
  NODE_GETUTXO = (1 << 1)
  NODE_BLOOM = (1 << 2)
  NODE_WITNESS = (1 << 3)
  
  # Keep our own socket map for asyncore, so that we can track disconnects
  # ourselves (to workaround an issue with closing an asyncore socket when
  # using select)
  mininode_socket_map = dict()
  
  # One lock for synchronizing all data access between the networking thread (see
  # NetworkThread below) and the thread running the test logic.  For simplicity,
  # NodeConn acquires this lock whenever delivering a message to to a NodeConnCB,
  # and whenever adding anything to the send buffer (in send_message()).  This
  # lock should be acquired in the thread running the test logic to synchronize
  # access to any data shared with the NodeConnCB or NodeConn.
  mininode_lock = RLock()
  
  # Serialization/deserialization tools
  def sha256(s):
      return hashlib.new('sha256', s).digest()
  
  def ripemd160(s):
      return hashlib.new('ripemd160', s).digest()
  
  def hash256(s):
      return sha256(sha256(s))
  
  def ser_compact_size(l):
      r = b""
      if l < 253:
          r = struct.pack("B", l)
      elif l < 0x10000:
          r = struct.pack("<BH", 253, l)
      elif l < 0x100000000:
          r = struct.pack("<BI", 254, l)
      else:
          r = struct.pack("<BQ", 255, l)
      return r
  
  def deser_compact_size(f):
      nit = struct.unpack("<B", f.read(1))[0]
      if nit == 253:
          nit = struct.unpack("<H", f.read(2))[0]
      elif nit == 254:
          nit = struct.unpack("<I", f.read(4))[0]
      elif nit == 255:
          nit = struct.unpack("<Q", f.read(8))[0]
      return nit
  
  def deser_string(f):
      nit = deser_compact_size(f)
      return f.read(nit)
  
  def ser_string(s):
      return ser_compact_size(len(s)) + s
  
  def deser_uint256(f):
      r = 0
      for i in range(8):
          t = struct.unpack("<I", f.read(4))[0]
          r += t << (i * 32)
      return r
  
  
  def ser_uint256(u):
      rs = b""
      for i in range(8):
          rs += struct.pack("<I", u & 0xFFFFFFFF)
          u >>= 32
      return rs
  
  
  def uint256_from_str(s):
      r = 0
      t = struct.unpack("<IIIIIIII", s[:32])
      for i in range(8):
          r += t[i] << (i * 32)
      return r
  
  
  def uint256_from_compact(c):
      nbytes = (c >> 24) & 0xFF
      v = (c & 0xFFFFFF) << (8 * (nbytes - 3))
      return v
  
  
  def deser_vector(f, c):
      nit = deser_compact_size(f)
      r = []
      for i in range(nit):
          t = c()
          t.deserialize(f)
          r.append(t)
      return r
  
  
  # ser_function_name: Allow for an alternate serialization function on the
  # entries in the vector (we use this for serializing the vector of transactions
  # for a witness block).
  def ser_vector(l, ser_function_name=None):
      r = ser_compact_size(len(l))
      for i in l:
          if ser_function_name:
              r += getattr(i, ser_function_name)()
          else:
              r += i.serialize()
      return r
  
  
  def deser_uint256_vector(f):
      nit = deser_compact_size(f)
      r = []
      for i in range(nit):
          t = deser_uint256(f)
          r.append(t)
      return r
  
  
  def ser_uint256_vector(l):
      r = ser_compact_size(len(l))
      for i in l:
          r += ser_uint256(i)
      return r
  
  
  def deser_string_vector(f):
      nit = deser_compact_size(f)
      r = []
      for i in range(nit):
          t = deser_string(f)
          r.append(t)
      return r
  
  
  def ser_string_vector(l):
      r = ser_compact_size(len(l))
      for sv in l:
          r += ser_string(sv)
      return r
  
  
  def deser_int_vector(f):
      nit = deser_compact_size(f)
      r = []
      for i in range(nit):
          t = struct.unpack("<i", f.read(4))[0]
          r.append(t)
      return r
  
  
  def ser_int_vector(l):
      r = ser_compact_size(len(l))
      for i in l:
          r += struct.pack("<i", i)
      return r
  
  # Deserialize from a hex string representation (eg from RPC)
  def FromHex(obj, hex_string):
      obj.deserialize(BytesIO(hex_str_to_bytes(hex_string)))
      return obj
  
  # Convert a binary-serializable object to hex (eg for submission via RPC)
  def ToHex(obj):
      return bytes_to_hex_str(obj.serialize())
  
  # Objects that map to lipcoind objects, which can be serialized/deserialized
  
  class CAddress(object):
      def __init__(self):
          self.nServices = 1
          self.pchReserved = b"\x00" * 10 + b"\xff" * 2
          self.ip = "0.0.0.0"
          self.port = 0
  
      def deserialize(self, f):
          self.nServices = struct.unpack("<Q", f.read(8))[0]
          self.pchReserved = f.read(12)
          self.ip = socket.inet_ntoa(f.read(4))
          self.port = struct.unpack(">H", f.read(2))[0]
  
      def serialize(self):
          r = b""
          r += struct.pack("<Q", self.nServices)
          r += self.pchReserved
          r += socket.inet_aton(self.ip)
          r += struct.pack(">H", self.port)
          return r
  
      def __repr__(self):
          return "CAddress(nServices=%i ip=%s port=%i)" % (self.nServices,
                                                           self.ip, self.port)
  
  MSG_WITNESS_FLAG = 1<<30
  
  class CInv(object):
      typemap = {
          0: "Error",
          1: "TX",
          2: "Block",
          1|MSG_WITNESS_FLAG: "WitnessTx",
          2|MSG_WITNESS_FLAG : "WitnessBlock",
          4: "CompactBlock"
      }
  
      def __init__(self, t=0, h=0):
          self.type = t
          self.hash = h
  
      def deserialize(self, f):
          self.type = struct.unpack("<i", f.read(4))[0]
          self.hash = deser_uint256(f)
  
      def serialize(self):
          r = b""
          r += struct.pack("<i", self.type)
          r += ser_uint256(self.hash)
          return r
  
      def __repr__(self):
          return "CInv(type=%s hash=%064x)" \
              % (self.typemap[self.type], self.hash)
  
  
  class CBlockLocator(object):
      def __init__(self):
          self.nVersion = MY_VERSION
          self.vHave = []
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.vHave = deser_uint256_vector(f)
  
      def serialize(self):
          r = b""
          r += struct.pack("<i", self.nVersion)
          r += ser_uint256_vector(self.vHave)
          return r
  
      def __repr__(self):
          return "CBlockLocator(nVersion=%i vHave=%s)" \
              % (self.nVersion, repr(self.vHave))
  
  
  class COutPoint(object):
      def __init__(self, hash=0, n=0):
          self.hash = hash
          self.n = n
  
      def deserialize(self, f):
          self.hash = deser_uint256(f)
          self.n = struct.unpack("<I", f.read(4))[0]
  
      def serialize(self):
          r = b""
          r += ser_uint256(self.hash)
          r += struct.pack("<I", self.n)
          return r
  
      def __repr__(self):
          return "COutPoint(hash=%064x n=%i)" % (self.hash, self.n)
  
  
  class CTxIn(object):
      def __init__(self, outpoint=None, scriptSig=b"", nSequence=0):
          if outpoint is None:
              self.prevout = COutPoint()
          else:
              self.prevout = outpoint
          self.scriptSig = scriptSig
          self.nSequence = nSequence
  
      def deserialize(self, f):
          self.prevout = COutPoint()
          self.prevout.deserialize(f)
          self.scriptSig = deser_string(f)
          self.nSequence = struct.unpack("<I", f.read(4))[0]
  
      def serialize(self):
          r = b""
          r += self.prevout.serialize()
          r += ser_string(self.scriptSig)
          r += struct.pack("<I", self.nSequence)
          return r
  
      def __repr__(self):
          return "CTxIn(prevout=%s scriptSig=%s nSequence=%i)" \
              % (repr(self.prevout), bytes_to_hex_str(self.scriptSig),
                 self.nSequence)
  
  
  class CTxOut(object):
      def __init__(self, nValue=0, scriptPubKey=b""):
          self.nValue = nValue
          self.scriptPubKey = scriptPubKey
  
      def deserialize(self, f):
          self.nValue = struct.unpack("<q", f.read(8))[0]
          self.scriptPubKey = deser_string(f)
  
      def serialize(self):
          r = b""
          r += struct.pack("<q", self.nValue)
          r += ser_string(self.scriptPubKey)
          return r
  
      def __repr__(self):
          return "CTxOut(nValue=%i.%08i scriptPubKey=%s)" \
              % (self.nValue // COIN, self.nValue % COIN,
                 bytes_to_hex_str(self.scriptPubKey))
  
  
  class CScriptWitness(object):
      def __init__(self):
          # stack is a vector of strings
          self.stack = []
  
      def __repr__(self):
          return "CScriptWitness(%s)" % \
                 (",".join([bytes_to_hex_str(x) for x in self.stack]))
  
      def is_null(self):
          if self.stack:
              return False
          return True
  
  
  class CTxInWitness(object):
      def __init__(self):
          self.scriptWitness = CScriptWitness()
  
      def deserialize(self, f):
          self.scriptWitness.stack = deser_string_vector(f)
  
      def serialize(self):
          return ser_string_vector(self.scriptWitness.stack)
  
      def __repr__(self):
          return repr(self.scriptWitness)
  
      def is_null(self):
          return self.scriptWitness.is_null()
  
  
  class CTxWitness(object):
      def __init__(self):
          self.vtxinwit = []
  
      def deserialize(self, f):
          for i in range(len(self.vtxinwit)):
              self.vtxinwit[i].deserialize(f)
  
      def serialize(self):
          r = b""
          # This is different than the usual vector serialization --
          # we omit the length of the vector, which is required to be
          # the same length as the transaction's vin vector.
          for x in self.vtxinwit:
              r += x.serialize()
          return r
  
      def __repr__(self):
          return "CTxWitness(%s)" % \
                 (';'.join([repr(x) for x in self.vtxinwit]))
  
      def is_null(self):
          for x in self.vtxinwit:
              if not x.is_null():
                  return False
          return True
  
  
  class CTransaction(object):
      def __init__(self, tx=None):
          if tx is None:
              self.nVersion = 1
              self.vin = []
              self.vout = []
              self.wit = CTxWitness()
              self.nLockTime = 0
              self.sha256 = None
              self.hash = None
          else:
              self.nVersion = tx.nVersion
              self.vin = copy.deepcopy(tx.vin)
              self.vout = copy.deepcopy(tx.vout)
              self.nLockTime = tx.nLockTime
              self.sha256 = tx.sha256
              self.hash = tx.hash
              self.wit = copy.deepcopy(tx.wit)
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.vin = deser_vector(f, CTxIn)
          flags = 0
          if len(self.vin) == 0:
              flags = struct.unpack("<B", f.read(1))[0]
              # Not sure why flags can't be zero, but this
              # matches the implementation in lipcoind
              if (flags != 0):
                  self.vin = deser_vector(f, CTxIn)
                  self.vout = deser_vector(f, CTxOut)
          else:
              self.vout = deser_vector(f, CTxOut)
          if flags != 0:
              self.wit.vtxinwit = [CTxInWitness() for i in range(len(self.vin))]
              self.wit.deserialize(f)
          self.nLockTime = struct.unpack("<I", f.read(4))[0]
          self.sha256 = None
          self.hash = None
  
      def serialize_without_witness(self):
          r = b""
          r += struct.pack("<i", self.nVersion)
          r += ser_vector(self.vin)
          r += ser_vector(self.vout)
          r += struct.pack("<I", self.nLockTime)
          return r
  
      # Only serialize with witness when explicitly called for
      def serialize_with_witness(self):
          flags = 0
          if not self.wit.is_null():
              flags |= 1
          r = b""
          r += struct.pack("<i", self.nVersion)
          if flags:
              dummy = []
              r += ser_vector(dummy)
              r += struct.pack("<B", flags)
          r += ser_vector(self.vin)
          r += ser_vector(self.vout)
          if flags & 1:
              if (len(self.wit.vtxinwit) != len(self.vin)):
                  # vtxinwit must have the same length as vin
                  self.wit.vtxinwit = self.wit.vtxinwit[:len(self.vin)]
                  for i in range(len(self.wit.vtxinwit), len(self.vin)):
                      self.wit.vtxinwit.append(CTxInWitness())
              r += self.wit.serialize()
          r += struct.pack("<I", self.nLockTime)
          return r
  
      # Regular serialization is without witness -- must explicitly
      # call serialize_with_witness to include witness data.
      def serialize(self):
          return self.serialize_without_witness()
  
      # Recalculate the txid (transaction hash without witness)
      def rehash(self):
          self.sha256 = None
          self.calc_sha256()
  
      # We will only cache the serialization without witness in
      # self.sha256 and self.hash -- those are expected to be the txid.
      def calc_sha256(self, with_witness=False):
          if with_witness:
              # Don't cache the result, just return it
              return uint256_from_str(hash256(self.serialize_with_witness()))
  
          if self.sha256 is None:
              self.sha256 = uint256_from_str(hash256(self.serialize_without_witness()))
          self.hash = encode(hash256(self.serialize())[::-1], 'hex_codec').decode('ascii')
  
      def is_valid(self):
          self.calc_sha256()
          for tout in self.vout:
              if tout.nValue < 0 or tout.nValue > 21000000 * COIN:
                  return False
          return True
  
      def __repr__(self):
          return "CTransaction(nVersion=%i vin=%s vout=%s wit=%s nLockTime=%i)" \
              % (self.nVersion, repr(self.vin), repr(self.vout), repr(self.wit), self.nLockTime)
  
  
  class CBlockHeader(object):
      def __init__(self, header=None):
          if header is None:
              self.set_null()
          else:
              self.nVersion = header.nVersion
              self.hashPrevBlock = header.hashPrevBlock
              self.hashMerkleRoot = header.hashMerkleRoot
              self.nTime = header.nTime
              self.nBits = header.nBits
              self.nNonce = header.nNonce
              self.sha256 = header.sha256
              self.hash = header.hash
              self.calc_sha256()
  
      def set_null(self):
          self.nVersion = 1
          self.hashPrevBlock = 0
          self.hashMerkleRoot = 0
          self.nTime = 0
          self.nBits = 0
          self.nNonce = 0
          self.sha256 = None
          self.hash = None
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.hashPrevBlock = deser_uint256(f)
          self.hashMerkleRoot = deser_uint256(f)
          self.nTime = struct.unpack("<I", f.read(4))[0]
          self.nBits = struct.unpack("<I", f.read(4))[0]
          self.nNonce = struct.unpack("<I", f.read(4))[0]
          self.sha256 = None
          self.hash = None
  
      def serialize(self):
          r = b""
          r += struct.pack("<i", self.nVersion)
          r += ser_uint256(self.hashPrevBlock)
          r += ser_uint256(self.hashMerkleRoot)
          r += struct.pack("<I", self.nTime)
          r += struct.pack("<I", self.nBits)
          r += struct.pack("<I", self.nNonce)
          return r
  
      def calc_sha256(self):
          if self.sha256 is None:
              r = b""
              r += struct.pack("<i", self.nVersion)
              r += ser_uint256(self.hashPrevBlock)
              r += ser_uint256(self.hashMerkleRoot)
              r += struct.pack("<I", self.nTime)
              r += struct.pack("<I", self.nBits)
              r += struct.pack("<I", self.nNonce)
              self.sha256 = uint256_from_str(hash256(r))
              self.hash = encode(hash256(r)[::-1], 'hex_codec').decode('ascii')
  
      def rehash(self):
          self.sha256 = None
          self.calc_sha256()
          return self.sha256
  
      def __repr__(self):
          return "CBlockHeader(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x)" \
              % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                 time.ctime(self.nTime), self.nBits, self.nNonce)
  
  
  class CBlock(CBlockHeader):
      def __init__(self, header=None):
          super(CBlock, self).__init__(header)
          self.vtx = []
  
      def deserialize(self, f):
          super(CBlock, self).deserialize(f)
          self.vtx = deser_vector(f, CTransaction)
  
      def serialize(self, with_witness=False):
          r = b""
          r += super(CBlock, self).serialize()
          if with_witness:
              r += ser_vector(self.vtx, "serialize_with_witness")
          else:
              r += ser_vector(self.vtx)
          return r
  
      # Calculate the merkle root given a vector of transaction hashes
      def get_merkle_root(self, hashes):
          while len(hashes) > 1:
              newhashes = []
              for i in range(0, len(hashes), 2):
                  i2 = min(i+1, len(hashes)-1)
                  newhashes.append(hash256(hashes[i] + hashes[i2]))
              hashes = newhashes
          return uint256_from_str(hashes[0])
  
      def calc_merkle_root(self):
          hashes = []
          for tx in self.vtx:
              tx.calc_sha256()
              hashes.append(ser_uint256(tx.sha256))
          return self.get_merkle_root(hashes)
  
      def calc_witness_merkle_root(self):
          # For witness root purposes, the hash of the
          # coinbase, with witness, is defined to be 0...0
          hashes = [ser_uint256(0)]
  
          for tx in self.vtx[1:]:
              # Calculate the hashes with witness data
              hashes.append(ser_uint256(tx.calc_sha256(True)))
  
          return self.get_merkle_root(hashes)
  
      def is_valid(self):
          self.calc_sha256()
          target = uint256_from_compact(self.nBits)
          if self.sha256 > target:
              return False
          for tx in self.vtx:
              if not tx.is_valid():
                  return False
          if self.calc_merkle_root() != self.hashMerkleRoot:
              return False
          return True
  
      def solve(self):
          self.rehash()
          target = uint256_from_compact(self.nBits)
          while self.sha256 > target:
              self.nNonce += 1
              self.rehash()
  
      def __repr__(self):
          return "CBlock(nVersion=%i hashPrevBlock=%064x hashMerkleRoot=%064x nTime=%s nBits=%08x nNonce=%08x vtx=%s)" \
              % (self.nVersion, self.hashPrevBlock, self.hashMerkleRoot,
                 time.ctime(self.nTime), self.nBits, self.nNonce, repr(self.vtx))
  
  
  class CUnsignedAlert(object):
      def __init__(self):
          self.nVersion = 1
          self.nRelayUntil = 0
          self.nExpiration = 0
          self.nID = 0
          self.nCancel = 0
          self.setCancel = []
          self.nMinVer = 0
          self.nMaxVer = 0
          self.setSubVer = []
          self.nPriority = 0
          self.strComment = b""
          self.strStatusBar = b""
          self.strReserved = b""
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          self.nRelayUntil = struct.unpack("<q", f.read(8))[0]
          self.nExpiration = struct.unpack("<q", f.read(8))[0]
          self.nID = struct.unpack("<i", f.read(4))[0]
          self.nCancel = struct.unpack("<i", f.read(4))[0]
          self.setCancel = deser_int_vector(f)
          self.nMinVer = struct.unpack("<i", f.read(4))[0]
          self.nMaxVer = struct.unpack("<i", f.read(4))[0]
          self.setSubVer = deser_string_vector(f)
          self.nPriority = struct.unpack("<i", f.read(4))[0]
          self.strComment = deser_string(f)
          self.strStatusBar = deser_string(f)
          self.strReserved = deser_string(f)
  
      def serialize(self):
          r = b""
          r += struct.pack("<i", self.nVersion)
          r += struct.pack("<q", self.nRelayUntil)
          r += struct.pack("<q", self.nExpiration)
          r += struct.pack("<i", self.nID)
          r += struct.pack("<i", self.nCancel)
          r += ser_int_vector(self.setCancel)
          r += struct.pack("<i", self.nMinVer)
          r += struct.pack("<i", self.nMaxVer)
          r += ser_string_vector(self.setSubVer)
          r += struct.pack("<i", self.nPriority)
          r += ser_string(self.strComment)
          r += ser_string(self.strStatusBar)
          r += ser_string(self.strReserved)
          return r
  
      def __repr__(self):
          return "CUnsignedAlert(nVersion %d, nRelayUntil %d, nExpiration %d, nID %d, nCancel %d, nMinVer %d, nMaxVer %d, nPriority %d, strComment %s, strStatusBar %s, strReserved %s)" \
              % (self.nVersion, self.nRelayUntil, self.nExpiration, self.nID,
                 self.nCancel, self.nMinVer, self.nMaxVer, self.nPriority,
                 self.strComment, self.strStatusBar, self.strReserved)
  
  
  class CAlert(object):
      def __init__(self):
          self.vchMsg = b""
          self.vchSig = b""
  
      def deserialize(self, f):
          self.vchMsg = deser_string(f)
          self.vchSig = deser_string(f)
  
      def serialize(self):
          r = b""
          r += ser_string(self.vchMsg)
          r += ser_string(self.vchSig)
          return r
  
      def __repr__(self):
          return "CAlert(vchMsg.sz %d, vchSig.sz %d)" \
              % (len(self.vchMsg), len(self.vchSig))
  
  
  class PrefilledTransaction(object):
      def __init__(self, index=0, tx = None):
          self.index = index
          self.tx = tx
  
      def deserialize(self, f):
          self.index = deser_compact_size(f)
          self.tx = CTransaction()
          self.tx.deserialize(f)
  
      def serialize(self, with_witness=False):
          r = b""
          r += ser_compact_size(self.index)
          if with_witness:
              r += self.tx.serialize_with_witness()
          else:
              r += self.tx.serialize_without_witness()
          return r
  
      def serialize_with_witness(self):
          return self.serialize(with_witness=True)
  
      def __repr__(self):
          return "PrefilledTransaction(index=%d, tx=%s)" % (self.index, repr(self.tx))
  
  # This is what we send on the wire, in a cmpctblock message.
  class P2PHeaderAndShortIDs(object):
      def __init__(self):
          self.header = CBlockHeader()
          self.nonce = 0
          self.shortids_length = 0
          self.shortids = []
          self.prefilled_txn_length = 0
          self.prefilled_txn = []
  
      def deserialize(self, f):
          self.header.deserialize(f)
          self.nonce = struct.unpack("<Q", f.read(8))[0]
          self.shortids_length = deser_compact_size(f)
          for i in range(self.shortids_length):
              # shortids are defined to be 6 bytes in the spec, so append
              # two zero bytes and read it in as an 8-byte number
              self.shortids.append(struct.unpack("<Q", f.read(6) + b'\x00\x00')[0])
          self.prefilled_txn = deser_vector(f, PrefilledTransaction)
          self.prefilled_txn_length = len(self.prefilled_txn)
  
      # When using version 2 compact blocks, we must serialize with_witness.
      def serialize(self, with_witness=False):
          r = b""
          r += self.header.serialize()
          r += struct.pack("<Q", self.nonce)
          r += ser_compact_size(self.shortids_length)
          for x in self.shortids:
              # We only want the first 6 bytes
              r += struct.pack("<Q", x)[0:6]
          if with_witness:
              r += ser_vector(self.prefilled_txn, "serialize_with_witness")
          else:
              r += ser_vector(self.prefilled_txn)
          return r
  
      def __repr__(self):
          return "P2PHeaderAndShortIDs(header=%s, nonce=%d, shortids_length=%d, shortids=%s, prefilled_txn_length=%d, prefilledtxn=%s" % (repr(self.header), self.nonce, self.shortids_length, repr(self.shortids), self.prefilled_txn_length, repr(self.prefilled_txn))
  
  # P2P version of the above that will use witness serialization (for compact
  # block version 2)
  class P2PHeaderAndShortWitnessIDs(P2PHeaderAndShortIDs):
      def serialize(self):
          return super(P2PHeaderAndShortWitnessIDs, self).serialize(with_witness=True)
  
  # Calculate the BIP 152-compact blocks shortid for a given transaction hash
  def calculate_shortid(k0, k1, tx_hash):
      expected_shortid = siphash256(k0, k1, tx_hash)
      expected_shortid &= 0x0000ffffffffffff
      return expected_shortid
  
  # This version gets rid of the array lengths, and reinterprets the differential
  # encoding into indices that can be used for lookup.
  class HeaderAndShortIDs(object):
      def __init__(self, p2pheaders_and_shortids = None):
          self.header = CBlockHeader()
          self.nonce = 0
          self.shortids = []
          self.prefilled_txn = []
          self.use_witness = False
  
          if p2pheaders_and_shortids != None:
              self.header = p2pheaders_and_shortids.header
              self.nonce = p2pheaders_and_shortids.nonce
              self.shortids = p2pheaders_and_shortids.shortids
              last_index = -1
              for x in p2pheaders_and_shortids.prefilled_txn:
                  self.prefilled_txn.append(PrefilledTransaction(x.index + last_index + 1, x.tx))
                  last_index = self.prefilled_txn[-1].index
  
      def to_p2p(self):
          if self.use_witness:
              ret = P2PHeaderAndShortWitnessIDs()
          else:
              ret = P2PHeaderAndShortIDs()
          ret.header = self.header
          ret.nonce = self.nonce
          ret.shortids_length = len(self.shortids)
          ret.shortids = self.shortids
          ret.prefilled_txn_length = len(self.prefilled_txn)
          ret.prefilled_txn = []
          last_index = -1
          for x in self.prefilled_txn:
              ret.prefilled_txn.append(PrefilledTransaction(x.index - last_index - 1, x.tx))
              last_index = x.index
          return ret
  
      def get_siphash_keys(self):
          header_nonce = self.header.serialize()
          header_nonce += struct.pack("<Q", self.nonce)
          hash_header_nonce_as_str = sha256(header_nonce)
          key0 = struct.unpack("<Q", hash_header_nonce_as_str[0:8])[0]
          key1 = struct.unpack("<Q", hash_header_nonce_as_str[8:16])[0]
          return [ key0, key1 ]
  
      # Version 2 compact blocks use wtxid in shortids (rather than txid)
      def initialize_from_block(self, block, nonce=0, prefill_list = [0], use_witness = False):
          self.header = CBlockHeader(block)
          self.nonce = nonce
          self.prefilled_txn = [ PrefilledTransaction(i, block.vtx[i]) for i in prefill_list ]
          self.shortids = []
          self.use_witness = use_witness
          [k0, k1] = self.get_siphash_keys()
          for i in range(len(block.vtx)):
              if i not in prefill_list:
                  tx_hash = block.vtx[i].sha256
                  if use_witness:
                      tx_hash = block.vtx[i].calc_sha256(with_witness=True)
                  self.shortids.append(calculate_shortid(k0, k1, tx_hash))
  
      def __repr__(self):
          return "HeaderAndShortIDs(header=%s, nonce=%d, shortids=%s, prefilledtxn=%s" % (repr(self.header), self.nonce, repr(self.shortids), repr(self.prefilled_txn))
  
  
  class BlockTransactionsRequest(object):
  
      def __init__(self, blockhash=0, indexes = None):
          self.blockhash = blockhash
          self.indexes = indexes if indexes != None else []
  
      def deserialize(self, f):
          self.blockhash = deser_uint256(f)
          indexes_length = deser_compact_size(f)
          for i in range(indexes_length):
              self.indexes.append(deser_compact_size(f))
  
      def serialize(self):
          r = b""
          r += ser_uint256(self.blockhash)
          r += ser_compact_size(len(self.indexes))
          for x in self.indexes:
              r += ser_compact_size(x)
          return r
  
      # helper to set the differentially encoded indexes from absolute ones
      def from_absolute(self, absolute_indexes):
          self.indexes = []
          last_index = -1
          for x in absolute_indexes:
              self.indexes.append(x-last_index-1)
              last_index = x
  
      def to_absolute(self):
          absolute_indexes = []
          last_index = -1
          for x in self.indexes:
              absolute_indexes.append(x+last_index+1)
              last_index = absolute_indexes[-1]
          return absolute_indexes
  
      def __repr__(self):
          return "BlockTransactionsRequest(hash=%064x indexes=%s)" % (self.blockhash, repr(self.indexes))
  
  
  class BlockTransactions(object):
  
      def __init__(self, blockhash=0, transactions = None):
          self.blockhash = blockhash
          self.transactions = transactions if transactions != None else []
  
      def deserialize(self, f):
          self.blockhash = deser_uint256(f)
          self.transactions = deser_vector(f, CTransaction)
  
      def serialize(self, with_witness=False):
          r = b""
          r += ser_uint256(self.blockhash)
          if with_witness:
              r += ser_vector(self.transactions, "serialize_with_witness")
          else:
              r += ser_vector(self.transactions)
          return r
  
      def __repr__(self):
          return "BlockTransactions(hash=%064x transactions=%s)" % (self.blockhash, repr(self.transactions))
  
  
  # Objects that correspond to messages on the wire
  class msg_version(object):
      command = b"version"
  
      def __init__(self):
          self.nVersion = MY_VERSION
          self.nServices = 1
          self.nTime = int(time.time())
          self.addrTo = CAddress()
          self.addrFrom = CAddress()
          self.nNonce = random.getrandbits(64)
          self.strSubVer = MY_SUBVERSION
          self.nStartingHeight = -1
          self.nRelay = MY_RELAY
  
      def deserialize(self, f):
          self.nVersion = struct.unpack("<i", f.read(4))[0]
          if self.nVersion == 10300:
              self.nVersion = 300
          self.nServices = struct.unpack("<Q", f.read(8))[0]
          self.nTime = struct.unpack("<q", f.read(8))[0]
          self.addrTo = CAddress()
          self.addrTo.deserialize(f)
  
          if self.nVersion >= 106:
              self.addrFrom = CAddress()
              self.addrFrom.deserialize(f)
              self.nNonce = struct.unpack("<Q", f.read(8))[0]
              self.strSubVer = deser_string(f)
          else:
              self.addrFrom = None
              self.nNonce = None
              self.strSubVer = None
              self.nStartingHeight = None
  
          if self.nVersion >= 209:
              self.nStartingHeight = struct.unpack("<i", f.read(4))[0]
          else:
              self.nStartingHeight = None
  
          if self.nVersion >= 70001:
              # Relay field is optional for version 70001 onwards
              try:
                  self.nRelay = struct.unpack("<b", f.read(1))[0]
              except:
                  self.nRelay = 0
          else:
              self.nRelay = 0
  
      def serialize(self):
          r = b""
          r += struct.pack("<i", self.nVersion)
          r += struct.pack("<Q", self.nServices)
          r += struct.pack("<q", self.nTime)
          r += self.addrTo.serialize()
          r += self.addrFrom.serialize()
          r += struct.pack("<Q", self.nNonce)
          r += ser_string(self.strSubVer)
          r += struct.pack("<i", self.nStartingHeight)
          r += struct.pack("<b", self.nRelay)
          return r
  
      def __repr__(self):
          return 'msg_version(nVersion=%i nServices=%i nTime=%s addrTo=%s addrFrom=%s nNonce=0x%016X strSubVer=%s nStartingHeight=%i nRelay=%i)' \
              % (self.nVersion, self.nServices, time.ctime(self.nTime),
                 repr(self.addrTo), repr(self.addrFrom), self.nNonce,
                 self.strSubVer, self.nStartingHeight, self.nRelay)
  
  
  class msg_verack(object):
      command = b"verack"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return b""
  
      def __repr__(self):
          return "msg_verack()"
  
  
  class msg_addr(object):
      command = b"addr"
  
      def __init__(self):
          self.addrs = []
  
      def deserialize(self, f):
          self.addrs = deser_vector(f, CAddress)
  
      def serialize(self):
          return ser_vector(self.addrs)
  
      def __repr__(self):
          return "msg_addr(addrs=%s)" % (repr(self.addrs))
  
  
  class msg_alert(object):
      command = b"alert"
  
      def __init__(self):
          self.alert = CAlert()
  
      def deserialize(self, f):
          self.alert = CAlert()
          self.alert.deserialize(f)
  
      def serialize(self):
          r = b""
          r += self.alert.serialize()
          return r
  
      def __repr__(self):
          return "msg_alert(alert=%s)" % (repr(self.alert), )
  
  
  class msg_inv(object):
      command = b"inv"
  
      def __init__(self, inv=None):
          if inv is None:
              self.inv = []
          else:
              self.inv = inv
  
      def deserialize(self, f):
          self.inv = deser_vector(f, CInv)
  
      def serialize(self):
          return ser_vector(self.inv)
  
      def __repr__(self):
          return "msg_inv(inv=%s)" % (repr(self.inv))
  
  
  class msg_getdata(object):
      command = b"getdata"
  
      def __init__(self, inv=None):
          self.inv = inv if inv != None else []
  
      def deserialize(self, f):
          self.inv = deser_vector(f, CInv)
  
      def serialize(self):
          return ser_vector(self.inv)
  
      def __repr__(self):
          return "msg_getdata(inv=%s)" % (repr(self.inv))
  
  
  class msg_getblocks(object):
      command = b"getblocks"
  
      def __init__(self):
          self.locator = CBlockLocator()
          self.hashstop = 0
  
      def deserialize(self, f):
          self.locator = CBlockLocator()
          self.locator.deserialize(f)
          self.hashstop = deser_uint256(f)
  
      def serialize(self):
          r = b""
          r += self.locator.serialize()
          r += ser_uint256(self.hashstop)
          return r
  
      def __repr__(self):
          return "msg_getblocks(locator=%s hashstop=%064x)" \
              % (repr(self.locator), self.hashstop)
  
  
  class msg_tx(object):
      command = b"tx"
  
      def __init__(self, tx=CTransaction()):
          self.tx = tx
  
      def deserialize(self, f):
          self.tx.deserialize(f)
  
      def serialize(self):
          return self.tx.serialize_without_witness()
  
      def __repr__(self):
          return "msg_tx(tx=%s)" % (repr(self.tx))
  
  class msg_witness_tx(msg_tx):
  
      def serialize(self):
          return self.tx.serialize_with_witness()
  
  
  class msg_block(object):
      command = b"block"
  
      def __init__(self, block=None):
          if block is None:
              self.block = CBlock()
          else:
              self.block = block
  
      def deserialize(self, f):
          self.block.deserialize(f)
  
      def serialize(self):
          return self.block.serialize()
  
      def __repr__(self):
          return "msg_block(block=%s)" % (repr(self.block))
  
  # for cases where a user needs tighter control over what is sent over the wire
  # note that the user must supply the name of the command, and the data
  class msg_generic(object):
      def __init__(self, command, data=None):
          self.command = command
          self.data = data
  
      def serialize(self):
          return self.data
  
      def __repr__(self):
          return "msg_generic()"
  
  class msg_witness_block(msg_block):
  
      def serialize(self):
          r = self.block.serialize(with_witness=True)
          return r
  
  class msg_getaddr(object):
      command = b"getaddr"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return b""
  
      def __repr__(self):
          return "msg_getaddr()"
  
  
  class msg_ping_prebip31(object):
      command = b"ping"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return b""
  
      def __repr__(self):
          return "msg_ping() (pre-bip31)"
  
  
  class msg_ping(object):
      command = b"ping"
  
      def __init__(self, nonce=0):
          self.nonce = nonce
  
      def deserialize(self, f):
          self.nonce = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = b""
          r += struct.pack("<Q", self.nonce)
          return r
  
      def __repr__(self):
          return "msg_ping(nonce=%08x)" % self.nonce
  
  
  class msg_pong(object):
      command = b"pong"
  
      def __init__(self, nonce=0):
          self.nonce = nonce
  
      def deserialize(self, f):
          self.nonce = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = b""
          r += struct.pack("<Q", self.nonce)
          return r
  
      def __repr__(self):
          return "msg_pong(nonce=%08x)" % self.nonce
  
  
  class msg_mempool(object):
      command = b"mempool"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return b""
  
      def __repr__(self):
          return "msg_mempool()"
  
  class msg_sendheaders(object):
      command = b"sendheaders"
  
      def __init__(self):
          pass
  
      def deserialize(self, f):
          pass
  
      def serialize(self):
          return b""
  
      def __repr__(self):
          return "msg_sendheaders()"
  
  
  # getheaders message has
  # number of entries
  # vector of hashes
  # hash_stop (hash of last desired block header, 0 to get as many as possible)
  class msg_getheaders(object):
      command = b"getheaders"
  
      def __init__(self):
          self.locator = CBlockLocator()
          self.hashstop = 0
  
      def deserialize(self, f):
          self.locator = CBlockLocator()
          self.locator.deserialize(f)
          self.hashstop = deser_uint256(f)
  
      def serialize(self):
          r = b""
          r += self.locator.serialize()
          r += ser_uint256(self.hashstop)
          return r
  
      def __repr__(self):
          return "msg_getheaders(locator=%s, stop=%064x)" \
              % (repr(self.locator), self.hashstop)
  
  
  # headers message has
  # <count> <vector of block headers>
  class msg_headers(object):
      command = b"headers"
  
      def __init__(self):
          self.headers = []
  
      def deserialize(self, f):
          # comment in lipcoind indicates these should be deserialized as blocks
          blocks = deser_vector(f, CBlock)
          for x in blocks:
              self.headers.append(CBlockHeader(x))
  
      def serialize(self):
          blocks = [CBlock(x) for x in self.headers]
          return ser_vector(blocks)
  
      def __repr__(self):
          return "msg_headers(headers=%s)" % repr(self.headers)
  
  
  class msg_reject(object):
      command = b"reject"
      REJECT_MALFORMED = 1
  
      def __init__(self):
          self.message = b""
          self.code = 0
          self.reason = b""
          self.data = 0
  
      def deserialize(self, f):
          self.message = deser_string(f)
          self.code = struct.unpack("<B", f.read(1))[0]
          self.reason = deser_string(f)
          if (self.code != self.REJECT_MALFORMED and
                  (self.message == b"block" or self.message == b"tx")):
              self.data = deser_uint256(f)
  
      def serialize(self):
          r = ser_string(self.message)
          r += struct.pack("<B", self.code)
          r += ser_string(self.reason)
          if (self.code != self.REJECT_MALFORMED and
                  (self.message == b"block" or self.message == b"tx")):
              r += ser_uint256(self.data)
          return r
  
      def __repr__(self):
          return "msg_reject: %s %d %s [%064x]" \
              % (self.message, self.code, self.reason, self.data)
  
  # Helper function
  def wait_until(predicate, *, attempts=float('inf'), timeout=float('inf')):
      attempt = 0
      elapsed = 0
  
      while attempt < attempts and elapsed < timeout:
          with mininode_lock:
              if predicate():
                  return True
          attempt += 1
          elapsed += 0.05
          time.sleep(0.05)
  
      return False
  
  class msg_feefilter(object):
      command = b"feefilter"
  
      def __init__(self, feerate=0):
          self.feerate = feerate
  
      def deserialize(self, f):
          self.feerate = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = b""
          r += struct.pack("<Q", self.feerate)
          return r
  
      def __repr__(self):
          return "msg_feefilter(feerate=%08x)" % self.feerate
  
  class msg_sendcmpct(object):
      command = b"sendcmpct"
  
      def __init__(self):
          self.announce = False
          self.version = 1
  
      def deserialize(self, f):
          self.announce = struct.unpack("<?", f.read(1))[0]
          self.version = struct.unpack("<Q", f.read(8))[0]
  
      def serialize(self):
          r = b""
          r += struct.pack("<?", self.announce)
          r += struct.pack("<Q", self.version)
          return r
  
      def __repr__(self):
          return "msg_sendcmpct(announce=%s, version=%lu)" % (self.announce, self.version)
  
  class msg_cmpctblock(object):
      command = b"cmpctblock"
  
      def __init__(self, header_and_shortids = None):
          self.header_and_shortids = header_and_shortids
  
      def deserialize(self, f):
          self.header_and_shortids = P2PHeaderAndShortIDs()
          self.header_and_shortids.deserialize(f)
  
      def serialize(self):
          r = b""
          r += self.header_and_shortids.serialize()
          return r
  
      def __repr__(self):
          return "msg_cmpctblock(HeaderAndShortIDs=%s)" % repr(self.header_and_shortids)
  
  class msg_getblocktxn(object):
      command = b"getblocktxn"
  
      def __init__(self):
          self.block_txn_request = None
  
      def deserialize(self, f):
          self.block_txn_request = BlockTransactionsRequest()
          self.block_txn_request.deserialize(f)
  
      def serialize(self):
          r = b""
          r += self.block_txn_request.serialize()
          return r
  
      def __repr__(self):
          return "msg_getblocktxn(block_txn_request=%s)" % (repr(self.block_txn_request))
  
  class msg_blocktxn(object):
      command = b"blocktxn"
  
      def __init__(self):
          self.block_transactions = BlockTransactions()
  
      def deserialize(self, f):
          self.block_transactions.deserialize(f)
  
      def serialize(self):
          r = b""
          r += self.block_transactions.serialize()
          return r
  
      def __repr__(self):
          return "msg_blocktxn(block_transactions=%s)" % (repr(self.block_transactions))
  
  class msg_witness_blocktxn(msg_blocktxn):
      def serialize(self):
          r = b""
          r += self.block_transactions.serialize(with_witness=True)
          return r
  
  # This is what a callback should look like for NodeConn
  # Reimplement the on_* functions to provide handling for events
  class NodeConnCB(object):
      def __init__(self):
          self.verack_received = False
          # deliver_sleep_time is helpful for debugging race conditions in p2p
          # tests; it causes message delivery to sleep for the specified time
          # before acquiring the global lock and delivering the next message.
          self.deliver_sleep_time = None
          # Remember the services our peer has advertised
          self.peer_services = None
  
      def set_deliver_sleep_time(self, value):
          with mininode_lock:
              self.deliver_sleep_time = value
  
      def get_deliver_sleep_time(self):
          with mininode_lock:
              return self.deliver_sleep_time
  
      # Spin until verack message is received from the node.
      # Tests may want to use this as a signal that the test can begin.
      # This can be called from the testing thread, so it needs to acquire the
      # global lock.
      def wait_for_verack(self):
          while True:
              with mininode_lock:
                  if self.verack_received:
                      return
              time.sleep(0.05)
  
      def deliver(self, conn, message):
          deliver_sleep = self.get_deliver_sleep_time()
          if deliver_sleep is not None:
              time.sleep(deliver_sleep)
          with mininode_lock:
              try:
                  getattr(self, 'on_' + message.command.decode('ascii'))(conn, message)
              except:
                  print("ERROR delivering %s (%s)" % (repr(message),
                                                      sys.exc_info()[0]))
  
      def on_version(self, conn, message):
          if message.nVersion >= 209:
              conn.send_message(msg_verack())
          conn.ver_send = min(MY_VERSION, message.nVersion)
          if message.nVersion < 209:
              conn.ver_recv = conn.ver_send
          conn.nServices = message.nServices
  
      def on_verack(self, conn, message):
          conn.ver_recv = conn.ver_send
          self.verack_received = True
  
      def on_inv(self, conn, message):
          want = msg_getdata()
          for i in message.inv:
              if i.type != 0:
                  want.inv.append(i)
          if len(want.inv):
              conn.send_message(want)
  
      def on_addr(self, conn, message): pass
      def on_alert(self, conn, message): pass
      def on_getdata(self, conn, message): pass
      def on_getblocks(self, conn, message): pass
      def on_tx(self, conn, message): pass
      def on_block(self, conn, message): pass
      def on_getaddr(self, conn, message): pass
      def on_headers(self, conn, message): pass
      def on_getheaders(self, conn, message): pass
      def on_ping(self, conn, message):
          if conn.ver_send > BIP0031_VERSION:
              conn.send_message(msg_pong(message.nonce))
      def on_reject(self, conn, message): pass
      def on_open(self, conn): pass
      def on_close(self, conn): pass
      def on_mempool(self, conn): pass
      def on_pong(self, conn, message): pass
      def on_feefilter(self, conn, message): pass
      def on_sendheaders(self, conn, message): pass
      def on_sendcmpct(self, conn, message): pass
      def on_cmpctblock(self, conn, message): pass
      def on_getblocktxn(self, conn, message): pass
      def on_blocktxn(self, conn, message): pass
  
  # More useful callbacks and functions for NodeConnCB's which have a single NodeConn
  class SingleNodeConnCB(NodeConnCB):
      def __init__(self):
          NodeConnCB.__init__(self)
          self.connection = None
          self.ping_counter = 1
          self.last_pong = msg_pong()
  
      def add_connection(self, conn):
          self.connection = conn
  
      # Wrapper for the NodeConn's send_message function
      def send_message(self, message):
          self.connection.send_message(message)
  
      def send_and_ping(self, message):
          self.send_message(message)
          self.sync_with_ping()
  
      def on_pong(self, conn, message):
          self.last_pong = message
  
      # Sync up with the node
      def sync_with_ping(self, timeout=30):
          def received_pong():
              return (self.last_pong.nonce == self.ping_counter)
          self.send_message(msg_ping(nonce=self.ping_counter))
          success = wait_until(received_pong, timeout=timeout)
          self.ping_counter += 1
          return success
  
  # The actual NodeConn class
  # This class provides an interface for a p2p connection to a specified node
  class NodeConn(asyncore.dispatcher):
      messagemap = {
          b"version": msg_version,
          b"verack": msg_verack,
          b"addr": msg_addr,
          b"alert": msg_alert,
          b"inv": msg_inv,
          b"getdata": msg_getdata,
          b"getblocks": msg_getblocks,
          b"tx": msg_tx,
          b"block": msg_block,
          b"getaddr": msg_getaddr,
          b"ping": msg_ping,
          b"pong": msg_pong,
          b"headers": msg_headers,
          b"getheaders": msg_getheaders,
          b"reject": msg_reject,
          b"mempool": msg_mempool,
          b"feefilter": msg_feefilter,
          b"sendheaders": msg_sendheaders,
          b"sendcmpct": msg_sendcmpct,
          b"cmpctblock": msg_cmpctblock,
          b"getblocktxn": msg_getblocktxn,
          b"blocktxn": msg_blocktxn
      }
      MAGIC_BYTES = {
          "mainnet": b"\xf9\xbe\xb4\xd9",   # mainnet
          "testnet3": b"\x0b\x11\x09\x07",  # testnet3
          "regtest": b"\xfa\xbf\xb5\xda",   # regtest
      }
  
      def __init__(self, dstaddr, dstport, rpc, callback, net="regtest", services=NODE_NETWORK, send_version=True):
          asyncore.dispatcher.__init__(self, map=mininode_socket_map)
          self.log = logging.getLogger("NodeConn(%s:%d)" % (dstaddr, dstport))
          self.dstaddr = dstaddr
          self.dstport = dstport
          self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
          self.sendbuf = b""
          self.recvbuf = b""
          self.ver_send = 209
          self.ver_recv = 209
          self.last_sent = 0
          self.state = "connecting"
          self.network = net
          self.cb = callback
          self.disconnect = False
          self.nServices = 0
  
          if send_version:
              # stuff version msg into sendbuf
              vt = msg_version()
              vt.nServices = services
              vt.addrTo.ip = self.dstaddr
              vt.addrTo.port = self.dstport
              vt.addrFrom.ip = "0.0.0.0"
              vt.addrFrom.port = 0
              self.send_message(vt, True)
  
          print('MiniNode: Connecting to LipCoin Node IP # ' + dstaddr + ':' \
              + str(dstport))
  
          try:
              self.connect((dstaddr, dstport))
          except:
              self.handle_close()
          self.rpc = rpc
  
      def show_debug_msg(self, msg):
          self.log.debug(msg)
  
      def handle_connect(self):
          if self.state != "connected":
              self.show_debug_msg("MiniNode: Connected & Listening: \n")
              self.state = "connected"
              self.cb.on_open(self)
  
      def handle_close(self):
          self.show_debug_msg("MiniNode: Closing Connection to %s:%d... "
                              % (self.dstaddr, self.dstport))
          self.state = "closed"
          self.recvbuf = b""
          self.sendbuf = b""
          try:
              self.close()
          except:
              pass
          self.cb.on_close(self)
  
      def handle_read(self):
          try:
              t = self.recv(8192)
              if len(t) > 0:
                  self.recvbuf += t
                  self.got_data()
          except:
              pass
  
      def readable(self):
          return True
  
      def writable(self):
          with mininode_lock:
              pre_connection = self.state == "connecting"
              length = len(self.sendbuf)
          return (length > 0 or pre_connection)
  
      def handle_write(self):
          with mininode_lock:
              # asyncore does not expose socket connection, only the first read/write
              # event, thus we must check connection manually here to know when we
              # actually connect
              if self.state == "connecting":
                  self.handle_connect()
              if not self.writable():
                  return
  
              try:
                  sent = self.send(self.sendbuf)
              except:
                  self.handle_close()
                  return
              self.sendbuf = self.sendbuf[sent:]
  
      def got_data(self):
          try:
              while True:
                  if len(self.recvbuf) < 4:
                      return
                  if self.recvbuf[:4] != self.MAGIC_BYTES[self.network]:
                      raise ValueError("got garbage %s" % repr(self.recvbuf))
                  if self.ver_recv < 209:
                      if len(self.recvbuf) < 4 + 12 + 4:
                          return
                      command = self.recvbuf[4:4+12].split(b"\x00", 1)[0]
                      msglen = struct.unpack("<i", self.recvbuf[4+12:4+12+4])[0]
                      checksum = None
                      if len(self.recvbuf) < 4 + 12 + 4 + msglen:
                          return
                      msg = self.recvbuf[4+12+4:4+12+4+msglen]
                      self.recvbuf = self.recvbuf[4+12+4+msglen:]
                  else:
                      if len(self.recvbuf) < 4 + 12 + 4 + 4:
                          return
                      command = self.recvbuf[4:4+12].split(b"\x00", 1)[0]
                      msglen = struct.unpack("<i", self.recvbuf[4+12:4+12+4])[0]
                      checksum = self.recvbuf[4+12+4:4+12+4+4]
                      if len(self.recvbuf) < 4 + 12 + 4 + 4 + msglen:
                          return
                      msg = self.recvbuf[4+12+4+4:4+12+4+4+msglen]
                      th = sha256(msg)
                      h = sha256(th)
                      if checksum != h[:4]:
                          raise ValueError("got bad checksum " + repr(self.recvbuf))
                      self.recvbuf = self.recvbuf[4+12+4+4+msglen:]
                  if command in self.messagemap:
                      f = BytesIO(msg)
                      t = self.messagemap[command]()
                      t.deserialize(f)
                      self.got_message(t)
                  else:
                      self.show_debug_msg("Unknown command: '" + command + "' " +
                                          repr(msg))
          except Exception as e:
              print('got_data:', repr(e))
              # import  traceback
              # traceback.print_tb(sys.exc_info()[2])
  
      def send_message(self, message, pushbuf=False):
          if self.state != "connected" and not pushbuf:
              raise IOError('Not connected, no pushbuf')
          self.show_debug_msg("Send %s" % repr(message))
          command = message.command
          data = message.serialize()
          tmsg = self.MAGIC_BYTES[self.network]
          tmsg += command
          tmsg += b"\x00" * (12 - len(command))
          tmsg += struct.pack("<I", len(data))
          if self.ver_send >= 209:
              th = sha256(data)
              h = sha256(th)
              tmsg += h[:4]
          tmsg += data
          with mininode_lock:
              self.sendbuf += tmsg
              self.last_sent = time.time()
  
      def got_message(self, message):
          if message.command == b"version":
              if message.nVersion <= BIP0031_VERSION:
                  self.messagemap[b'ping'] = msg_ping_prebip31
          if self.last_sent + 30 * 60 < time.time():
              self.send_message(self.messagemap[b'ping']())
          self.show_debug_msg("Recv %s" % repr(message))
          self.cb.deliver(self, message)
  
      def disconnect_node(self):
          self.disconnect = True
  
  
  class NetworkThread(Thread):
      def run(self):
          while mininode_socket_map:
              # We check for whether to disconnect outside of the asyncore
              # loop to workaround the behavior of asyncore when using
              # select
              disconnected = []
              for fd, obj in mininode_socket_map.items():
                  if obj.disconnect:
                      disconnected.append(obj)
              [ obj.handle_close() for obj in disconnected ]
              asyncore.loop(0.1, use_poll=True, map=mininode_socket_map, count=1)
  
  
  # An exception we can raise if we detect a potential disconnect
  # (p2p or rpc) before the test is complete
  class EarlyDisconnectError(Exception):
      def __init__(self, value):
          self.value = value
  
      def __str__(self):
          return repr(self.value)
  