Remove duplicate method definitions in NodeConnCB subclasses

All Node classes in individual test cases subclass from NodeConnCB. Many
have duplicate definitions for methods that are defined in the base
class. This commit removes those duplicate definitions.

This commit removes ~290 lines of duplicate code.
This commit is contained in:
John Newbery 2017-03-30 08:38:46 -04:00
parent 52e15aa4d0
commit 2a52ae63bf
12 changed files with 144 additions and 451 deletions

View File

@ -10,54 +10,24 @@ if uploadtarget has been reached.
if uploadtarget has been reached.
* Verify that the upload counters are reset after 24 hours.
"""
from collections import defaultdict
import time
from test_framework.mininode import *
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *
import time
# TestNode: bare-bones "peer". Used mostly as a conduit for a test to sending
# p2p messages to a node, generating the messages in the main testing logic.
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.ping_counter = 1
self.last_pong = msg_pong()
self.block_receive_map = {}
def add_connection(self, conn):
self.connection = conn
self.peer_disconnected = False
self.block_receive_map = defaultdict(int)
def on_inv(self, conn, message):
pass
# Track the last getdata message we receive (used in the test)
def on_getdata(self, conn, message):
self.last_getdata = message
def on_block(self, conn, message):
message.block.calc_sha256()
try:
self.block_receive_map[message.block.sha256] += 1
except KeyError as e:
self.block_receive_map[message.block.sha256] = 1
def wait_for_disconnect(self):
def disconnected():
return self.peer_disconnected
return wait_until(disconnected, timeout=10)
# Wrapper for the NodeConn's send_message function
def send_message(self, message):
self.connection.send_message(message)
def on_pong(self, conn, message):
self.last_pong = message
def on_close(self, conn):
self.peer_disconnected = True
class MaxUploadTest(BitcoinTestFramework):
@ -183,33 +153,26 @@ class MaxUploadTest(BitcoinTestFramework):
stop_node(self.nodes[0], 0)
self.nodes[0] = start_node(0, self.options.tmpdir, ["-whitelist=127.0.0.1", "-maxuploadtarget=1", "-blockmaxsize=999000"])
#recreate/reconnect 3 test nodes
test_nodes = []
connections = []
for i in range(3):
test_nodes.append(TestNode())
connections.append(NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_nodes[i]))
test_nodes[i].add_connection(connections[i])
#recreate/reconnect a test node
test_nodes = [TestNode()]
connections = [NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_nodes[0])]
test_nodes[0].add_connection(connections[0])
NetworkThread().start() # Start up network handling in another thread
[x.wait_for_verack() for x in test_nodes]
test_nodes[0].wait_for_verack()
#retrieve 20 blocks which should be enough to break the 1MB limit
getdata_request.inv = [CInv(2, big_new_block)]
for i in range(20):
test_nodes[1].send_message(getdata_request)
test_nodes[1].sync_with_ping()
assert_equal(test_nodes[1].block_receive_map[big_new_block], i+1)
test_nodes[0].send_message(getdata_request)
test_nodes[0].sync_with_ping()
assert_equal(test_nodes[0].block_receive_map[big_new_block], i+1)
getdata_request.inv = [CInv(2, big_old_block)]
test_nodes[1].send_message(getdata_request)
test_nodes[1].wait_for_disconnect()
assert_equal(len(self.nodes[0].getpeerinfo()), 3) #node is still connected because of the whitelist
test_nodes[0].send_and_ping(getdata_request)
assert_equal(len(self.nodes[0].getpeerinfo()), 1) #node is still connected because of the whitelist
self.log.info("Peer 1 still connected after trying to download old block (whitelisted)")
[c.disconnect_node() for c in connections]
self.log.info("Peer still connected after trying to download old block (whitelisted)")
if __name__ == '__main__':
MaxUploadTest().main()

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@ -54,29 +54,6 @@ from test_framework.util import *
import time
from test_framework.blocktools import create_block, create_coinbase
# TestNode: bare-bones "peer". Used mostly as a conduit for a test to sending
# p2p messages to a node, generating the messages in the main testing logic.
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.ping_counter = 1
self.last_pong = msg_pong()
def add_connection(self, conn):
self.connection = conn
# Track the last getdata message we receive (used in the test)
def on_getdata(self, conn, message):
self.last_getdata = message
# Wrapper for the NodeConn's send_message function
def send_message(self, message):
self.connection.send_message(message)
def on_pong(self, conn, message):
self.last_pong = message
class AcceptBlockTest(BitcoinTestFramework):
def add_options(self, parser):
parser.add_option("--testbinary", dest="testbinary",
@ -101,8 +78,8 @@ class AcceptBlockTest(BitcoinTestFramework):
def run_test(self):
# Setup the p2p connections and start up the network thread.
test_node = TestNode() # connects to node0 (not whitelisted)
white_node = TestNode() # connects to node1 (whitelisted)
test_node = NodeConnCB() # connects to node0 (not whitelisted)
white_node = NodeConnCB() # connects to node1 (whitelisted)
connections = []
connections.append(NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], test_node))
@ -227,12 +204,12 @@ class AcceptBlockTest(BitcoinTestFramework):
# triggers a getdata on block 2 (it should if block 2 is missing).
with mininode_lock:
# Clear state so we can check the getdata request
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
test_node.send_message(msg_inv([CInv(2, blocks_h3[0].sha256)]))
test_node.sync_with_ping()
with mininode_lock:
getdata = test_node.last_getdata
getdata = test_node.last_message["getdata"]
# Check that the getdata includes the right block
assert_equal(getdata.inv[0].hash, blocks_h2f[0].sha256)

View File

@ -19,64 +19,31 @@ class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.last_sendcmpct = []
self.last_headers = None
self.last_inv = None
self.last_cmpctblock = None
self.block_announced = False
self.last_getdata = None
self.last_getheaders = None
self.last_getblocktxn = None
self.last_block = None
self.last_blocktxn = None
# Store the hashes of blocks we've seen announced.
# This is for synchronizing the p2p message traffic,
# so we can eg wait until a particular block is announced.
self.set_announced_blockhashes = set()
self.connected = False
def on_open(self, conn):
self.connected = True
def on_close(self, conn):
self.connected = False
self.announced_blockhashes = set()
def on_sendcmpct(self, conn, message):
self.last_sendcmpct.append(message)
def on_block(self, conn, message):
self.last_block = message
def on_cmpctblock(self, conn, message):
self.last_cmpctblock = message
self.block_announced = True
self.last_cmpctblock.header_and_shortids.header.calc_sha256()
self.set_announced_blockhashes.add(self.last_cmpctblock.header_and_shortids.header.sha256)
self.last_message["cmpctblock"].header_and_shortids.header.calc_sha256()
self.announced_blockhashes.add(self.last_message["cmpctblock"].header_and_shortids.header.sha256)
def on_headers(self, conn, message):
self.last_headers = message
self.block_announced = True
for x in self.last_headers.headers:
for x in self.last_message["headers"].headers:
x.calc_sha256()
self.set_announced_blockhashes.add(x.sha256)
self.announced_blockhashes.add(x.sha256)
def on_inv(self, conn, message):
self.last_inv = message
for x in self.last_inv.inv:
for x in self.last_message["inv"].inv:
if x.type == 2:
self.block_announced = True
self.set_announced_blockhashes.add(x.hash)
def on_getdata(self, conn, message):
self.last_getdata = message
def on_getheaders(self, conn, message):
self.last_getheaders = message
def on_getblocktxn(self, conn, message):
self.last_getblocktxn = message
def on_blocktxn(self, conn, message):
self.last_blocktxn = message
self.announced_blockhashes.add(x.hash)
# Requires caller to hold mininode_lock
def received_block_announcement(self):
@ -85,9 +52,9 @@ class TestNode(NodeConnCB):
def clear_block_announcement(self):
with mininode_lock:
self.block_announced = False
self.last_inv = None
self.last_headers = None
self.last_cmpctblock = None
self.last_message.pop("inv", None)
self.last_message.pop("headers", None)
self.last_message.pop("cmpctblock", None)
def get_headers(self, locator, hashstop):
msg = msg_getheaders()
@ -103,15 +70,14 @@ class TestNode(NodeConnCB):
def request_headers_and_sync(self, locator, hashstop=0):
self.clear_block_announcement()
self.get_headers(locator, hashstop)
assert(wait_until(self.received_block_announcement, timeout=30))
assert(self.received_block_announcement())
assert wait_until(self.received_block_announcement, timeout=30)
self.clear_block_announcement()
# Block until a block announcement for a particular block hash is
# received.
def wait_for_block_announcement(self, block_hash, timeout=30):
def received_hash():
return (block_hash in self.set_announced_blockhashes)
return (block_hash in self.announced_blockhashes)
return wait_until(received_hash, timeout=timeout)
def send_await_disconnect(self, message, timeout=30):
@ -214,14 +180,14 @@ class CompactBlocksTest(BitcoinTestFramework):
with mininode_lock:
assert predicate(peer), (
"block_hash={!r}, cmpctblock={!r}, inv={!r}".format(
block_hash, peer.last_cmpctblock, peer.last_inv))
block_hash, peer.last_message.get("cmpctblock", None), peer.last_message.get("inv", None)))
# We shouldn't get any block announcements via cmpctblock yet.
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" not in p.last_message)
# Try one more time, this time after requesting headers.
test_node.request_headers_and_sync(locator=[tip])
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is None and p.last_inv is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" not in p.last_message and "inv" in p.last_message)
# Test a few ways of using sendcmpct that should NOT
# result in compact block announcements.
@ -233,7 +199,7 @@ class CompactBlocksTest(BitcoinTestFramework):
sendcmpct.version = preferred_version+1
sendcmpct.announce = True
test_node.send_and_ping(sendcmpct)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" not in p.last_message)
# Headers sync before next test.
test_node.request_headers_and_sync(locator=[tip])
@ -242,7 +208,7 @@ class CompactBlocksTest(BitcoinTestFramework):
sendcmpct.version = preferred_version
sendcmpct.announce = False
test_node.send_and_ping(sendcmpct)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" not in p.last_message)
# Headers sync before next test.
test_node.request_headers_and_sync(locator=[tip])
@ -251,26 +217,26 @@ class CompactBlocksTest(BitcoinTestFramework):
sendcmpct.version = preferred_version
sendcmpct.announce = True
test_node.send_and_ping(sendcmpct)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" in p.last_message)
# Try one more time (no headers sync should be needed!)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" in p.last_message)
# Try one more time, after turning on sendheaders
test_node.send_and_ping(msg_sendheaders())
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" in p.last_message)
# Try one more time, after sending a version-1, announce=false message.
sendcmpct.version = preferred_version-1
sendcmpct.announce = False
test_node.send_and_ping(sendcmpct)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" in p.last_message)
# Now turn off announcements
sendcmpct.version = preferred_version
sendcmpct.announce = False
test_node.send_and_ping(sendcmpct)
check_announcement_of_new_block(node, test_node, lambda p: p.last_cmpctblock is None and p.last_headers is not None)
check_announcement_of_new_block(node, test_node, lambda p: "cmpctblock" not in p.last_message and "headers" in p.last_message)
if old_node is not None:
# Verify that a peer using an older protocol version can receive
@ -280,7 +246,7 @@ class CompactBlocksTest(BitcoinTestFramework):
old_node.send_and_ping(sendcmpct)
# Header sync
old_node.request_headers_and_sync(locator=[tip])
check_announcement_of_new_block(node, old_node, lambda p: p.last_cmpctblock is not None)
check_announcement_of_new_block(node, old_node, lambda p: "cmpctblock" in p.last_message)
# This test actually causes bitcoind to (reasonably!) disconnect us, so do this last.
def test_invalid_cmpctblock_message(self):
@ -345,9 +311,9 @@ class CompactBlocksTest(BitcoinTestFramework):
# Now fetch and check the compact block
header_and_shortids = None
with mininode_lock:
assert(test_node.last_cmpctblock is not None)
assert("cmpctblock" in test_node.last_message)
# Convert the on-the-wire representation to absolute indexes
header_and_shortids = HeaderAndShortIDs(test_node.last_cmpctblock.header_and_shortids)
header_and_shortids = HeaderAndShortIDs(test_node.last_message["cmpctblock"].header_and_shortids)
self.check_compactblock_construction_from_block(version, header_and_shortids, block_hash, block)
# Now fetch the compact block using a normal non-announce getdata
@ -362,9 +328,9 @@ class CompactBlocksTest(BitcoinTestFramework):
# Now fetch and check the compact block
header_and_shortids = None
with mininode_lock:
assert(test_node.last_cmpctblock is not None)
assert("cmpctblock" in test_node.last_message)
# Convert the on-the-wire representation to absolute indexes
header_and_shortids = HeaderAndShortIDs(test_node.last_cmpctblock.header_and_shortids)
header_and_shortids = HeaderAndShortIDs(test_node.last_message["cmpctblock"].header_and_shortids)
self.check_compactblock_construction_from_block(version, header_and_shortids, block_hash, block)
def check_compactblock_construction_from_block(self, version, header_and_shortids, block_hash, block):
@ -424,20 +390,20 @@ class CompactBlocksTest(BitcoinTestFramework):
for announce in ["inv", "header"]:
block = self.build_block_on_tip(node, segwit=segwit)
with mininode_lock:
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
if announce == "inv":
test_node.send_message(msg_inv([CInv(2, block.sha256)]))
success = wait_until(lambda: test_node.last_getheaders is not None, timeout=30)
success = wait_until(lambda: "getheaders" in test_node.last_message, timeout=30)
assert(success)
test_node.send_header_for_blocks([block])
else:
test_node.send_header_for_blocks([block])
success = wait_until(lambda: test_node.last_getdata is not None, timeout=30)
success = wait_until(lambda: "getdata" in test_node.last_message, timeout=30)
assert(success)
assert_equal(len(test_node.last_getdata.inv), 1)
assert_equal(test_node.last_getdata.inv[0].type, 4)
assert_equal(test_node.last_getdata.inv[0].hash, block.sha256)
assert_equal(len(test_node.last_message["getdata"].inv), 1)
assert_equal(test_node.last_message["getdata"].inv[0].type, 4)
assert_equal(test_node.last_message["getdata"].inv[0].hash, block.sha256)
# Send back a compactblock message that omits the coinbase
comp_block = HeaderAndShortIDs()
@ -453,8 +419,8 @@ class CompactBlocksTest(BitcoinTestFramework):
assert_equal(int(node.getbestblockhash(), 16), block.hashPrevBlock)
# Expect a getblocktxn message.
with mininode_lock:
assert(test_node.last_getblocktxn is not None)
absolute_indexes = test_node.last_getblocktxn.block_txn_request.to_absolute()
assert("getblocktxn" in test_node.last_message)
absolute_indexes = test_node.last_message["getblocktxn"].block_txn_request.to_absolute()
assert_equal(absolute_indexes, [0]) # should be a coinbase request
# Send the coinbase, and verify that the tip advances.
@ -493,8 +459,8 @@ class CompactBlocksTest(BitcoinTestFramework):
msg = msg_cmpctblock(compact_block.to_p2p())
peer.send_and_ping(msg)
with mininode_lock:
assert(peer.last_getblocktxn is not None)
absolute_indexes = peer.last_getblocktxn.block_txn_request.to_absolute()
assert("getblocktxn" in peer.last_message)
absolute_indexes = peer.last_message["getblocktxn"].block_txn_request.to_absolute()
assert_equal(absolute_indexes, expected_result)
def test_tip_after_message(node, peer, msg, tip):
@ -558,14 +524,14 @@ class CompactBlocksTest(BitcoinTestFramework):
# Clear out last request.
with mininode_lock:
test_node.last_getblocktxn = None
test_node.last_message.pop("getblocktxn", None)
# Send compact block
comp_block.initialize_from_block(block, prefill_list=[0], use_witness=with_witness)
test_tip_after_message(node, test_node, msg_cmpctblock(comp_block.to_p2p()), block.sha256)
with mininode_lock:
# Shouldn't have gotten a request for any transaction
assert(test_node.last_getblocktxn is None)
assert("getblocktxn" not in test_node.last_message)
# Incorrectly responding to a getblocktxn shouldn't cause the block to be
# permanently failed.
@ -591,8 +557,8 @@ class CompactBlocksTest(BitcoinTestFramework):
test_node.send_and_ping(msg_cmpctblock(comp_block.to_p2p()))
absolute_indexes = []
with mininode_lock:
assert(test_node.last_getblocktxn is not None)
absolute_indexes = test_node.last_getblocktxn.block_txn_request.to_absolute()
assert("getblocktxn" in test_node.last_message)
absolute_indexes = test_node.last_message["getblocktxn"].block_txn_request.to_absolute()
assert_equal(absolute_indexes, [6, 7, 8, 9, 10])
# Now give an incorrect response.
@ -613,11 +579,11 @@ class CompactBlocksTest(BitcoinTestFramework):
assert_equal(int(node.getbestblockhash(), 16), block.hashPrevBlock)
# We should receive a getdata request
success = wait_until(lambda: test_node.last_getdata is not None, timeout=10)
success = wait_until(lambda: "getdata" in test_node.last_message, timeout=10)
assert(success)
assert_equal(len(test_node.last_getdata.inv), 1)
assert(test_node.last_getdata.inv[0].type == 2 or test_node.last_getdata.inv[0].type == 2|MSG_WITNESS_FLAG)
assert_equal(test_node.last_getdata.inv[0].hash, block.sha256)
assert_equal(len(test_node.last_message["getdata"].inv), 1)
assert(test_node.last_message["getdata"].inv[0].type == 2 or test_node.last_message["getdata"].inv[0].type == 2|MSG_WITNESS_FLAG)
assert_equal(test_node.last_message["getdata"].inv[0].hash, block.sha256)
# Deliver the block
if version==2:
@ -641,15 +607,15 @@ class CompactBlocksTest(BitcoinTestFramework):
num_to_request = random.randint(1, len(block.vtx))
msg.block_txn_request.from_absolute(sorted(random.sample(range(len(block.vtx)), num_to_request)))
test_node.send_message(msg)
success = wait_until(lambda: test_node.last_blocktxn is not None, timeout=10)
success = wait_until(lambda: "blocktxn" in test_node.last_message, timeout=10)
assert(success)
[tx.calc_sha256() for tx in block.vtx]
with mininode_lock:
assert_equal(test_node.last_blocktxn.block_transactions.blockhash, int(block_hash, 16))
assert_equal(test_node.last_message["blocktxn"].block_transactions.blockhash, int(block_hash, 16))
all_indices = msg.block_txn_request.to_absolute()
for index in all_indices:
tx = test_node.last_blocktxn.block_transactions.transactions.pop(0)
tx = test_node.last_message["blocktxn"].block_transactions.transactions.pop(0)
tx.calc_sha256()
assert_equal(tx.sha256, block.vtx[index].sha256)
if version == 1:
@ -658,7 +624,7 @@ class CompactBlocksTest(BitcoinTestFramework):
else:
# Check that the witness matches
assert_equal(tx.calc_sha256(True), block.vtx[index].calc_sha256(True))
test_node.last_blocktxn = None
test_node.last_message.pop("blocktxn", None)
current_height -= 1
# Next request should send a full block response, as we're past the
@ -666,13 +632,13 @@ class CompactBlocksTest(BitcoinTestFramework):
block_hash = node.getblockhash(current_height)
msg.block_txn_request = BlockTransactionsRequest(int(block_hash, 16), [0])
with mininode_lock:
test_node.last_block = None
test_node.last_blocktxn = None
test_node.last_message.pop("block", None)
test_node.last_message.pop("blocktxn", None)
test_node.send_and_ping(msg)
with mininode_lock:
test_node.last_block.block.calc_sha256()
assert_equal(test_node.last_block.block.sha256, int(block_hash, 16))
assert_equal(test_node.last_blocktxn, None)
test_node.last_message["block"].block.calc_sha256()
assert_equal(test_node.last_message["block"].block.sha256, int(block_hash, 16))
assert "blocktxn" not in test_node.last_message
def test_compactblocks_not_at_tip(self, node, test_node):
# Test that requesting old compactblocks doesn't work.
@ -685,7 +651,7 @@ class CompactBlocksTest(BitcoinTestFramework):
test_node.clear_block_announcement()
test_node.send_message(msg_getdata([CInv(4, int(new_blocks[0], 16))]))
success = wait_until(lambda: test_node.last_cmpctblock is not None, timeout=30)
success = wait_until(lambda: "cmpctblock" in test_node.last_message, timeout=30)
assert(success)
test_node.clear_block_announcement()
@ -693,13 +659,13 @@ class CompactBlocksTest(BitcoinTestFramework):
wait_until(test_node.received_block_announcement, timeout=30)
test_node.clear_block_announcement()
with mininode_lock:
test_node.last_block = None
test_node.last_message.pop("block", None)
test_node.send_message(msg_getdata([CInv(4, int(new_blocks[0], 16))]))
success = wait_until(lambda: test_node.last_block is not None, timeout=30)
success = wait_until(lambda: "block" in test_node.last_message, timeout=30)
assert(success)
with mininode_lock:
test_node.last_block.block.calc_sha256()
assert_equal(test_node.last_block.block.sha256, int(new_blocks[0], 16))
test_node.last_message["block"].block.calc_sha256()
assert_equal(test_node.last_message["block"].block.sha256, int(new_blocks[0], 16))
# Generate an old compactblock, and verify that it's not accepted.
cur_height = node.getblockcount()
@ -726,10 +692,10 @@ class CompactBlocksTest(BitcoinTestFramework):
msg = msg_getblocktxn()
msg.block_txn_request = BlockTransactionsRequest(block.sha256, [0])
with mininode_lock:
test_node.last_blocktxn = None
test_node.last_message.pop("blocktxn", None)
test_node.send_and_ping(msg)
with mininode_lock:
assert(test_node.last_blocktxn is None)
assert "blocktxn" not in test_node.last_message
def activate_segwit(self, node):
node.generate(144*3)
@ -750,9 +716,9 @@ class CompactBlocksTest(BitcoinTestFramework):
wait_until(lambda: l.received_block_announcement(), timeout=30)
with mininode_lock:
for l in listeners:
assert(l.last_cmpctblock is not None)
l.last_cmpctblock.header_and_shortids.header.calc_sha256()
assert_equal(l.last_cmpctblock.header_and_shortids.header.sha256, block.sha256)
assert "cmpctblock" in l.last_message
l.last_message["cmpctblock"].header_and_shortids.header.calc_sha256()
assert_equal(l.last_message["cmpctblock"].header_and_shortids.header.sha256, block.sha256)
# Test that we don't get disconnected if we relay a compact block with valid header,
# but invalid transactions.
@ -804,7 +770,7 @@ class CompactBlocksTest(BitcoinTestFramework):
msg = msg_cmpctblock(cmpct_block.to_p2p())
peer.send_and_ping(msg)
with mininode_lock:
assert(peer.last_getblocktxn is not None)
assert "getblocktxn" in peer.last_message
return block, cmpct_block
block, cmpct_block = announce_cmpct_block(node, stalling_peer)

View File

@ -22,8 +22,6 @@ def allInvsMatch(invsExpected, testnode):
time.sleep(1)
return False
# TestNode: bare-bones "peer". Used to track which invs are received from a node
# and to send the node feefilter messages.
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
@ -38,10 +36,6 @@ class TestNode(NodeConnCB):
with mininode_lock:
self.txinvs = []
def send_filter(self, feerate):
self.send_message(msg_feefilter(feerate))
self.sync_with_ping()
class FeeFilterTest(BitcoinTestFramework):
def __init__(self):
@ -78,7 +72,7 @@ class FeeFilterTest(BitcoinTestFramework):
test_node.clear_invs()
# Set a filter of 15 sat/byte
test_node.send_filter(15000)
test_node.send_and_ping(msg_feefilter(15000))
# Test that txs are still being received (paying 20 sat/byte)
txids = [node1.sendtoaddress(node1.getnewaddress(), 1) for x in range(3)]
@ -103,7 +97,7 @@ class FeeFilterTest(BitcoinTestFramework):
test_node.clear_invs()
# Remove fee filter and check that txs are received again
test_node.send_filter(0)
test_node.send_and_ping(msg_feefilter(0))
txids = [node1.sendtoaddress(node1.getnewaddress(), 1) for x in range(3)]
assert(allInvsMatch(txids, test_node))
test_node.clear_invs()

View File

@ -20,17 +20,9 @@ banscore = 10
class CLazyNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.unexpected_msg = False
self.connected = False
self.ever_connected = False
def add_connection(self, conn):
self.connection = conn
def send_message(self, message):
self.connection.send_message(message)
def bad_message(self, message):
self.unexpected_msg = True
self.log.info("should not have received message: %s" % message.command)
@ -65,9 +57,6 @@ class CLazyNode(NodeConnCB):
# Node that never sends a version. We'll use this to send a bunch of messages
# anyway, and eventually get disconnected.
class CNodeNoVersionBan(CLazyNode):
def __init__(self):
super().__init__()
# send a bunch of veracks without sending a message. This should get us disconnected.
# NOTE: implementation-specific check here. Remove if bitcoind ban behavior changes
def on_open(self, conn):

View File

@ -12,51 +12,6 @@ from test_framework.mininode import *
from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.ping_counter = 1
self.last_pong = msg_pong()
self.block_receive_map = {}
def add_connection(self, conn):
self.connection = conn
self.peer_disconnected = False
def on_inv(self, conn, message):
pass
# Track the last getdata message we receive (used in the test)
def on_getdata(self, conn, message):
self.last_getdata = message
def on_block(self, conn, message):
message.block.calc_sha256()
try:
self.block_receive_map[message.block.sha256] += 1
except KeyError as e:
self.block_receive_map[message.block.sha256] = 1
def wait_for_disconnect(self):
def disconnected():
return self.peer_disconnected
return wait_until(disconnected, timeout=10)
# Wrapper for the NodeConn's send_message function
def send_message(self, message):
self.connection.send_message(message)
def on_pong(self, conn, message):
self.last_pong = message
def on_close(self, conn):
self.peer_disconnected = True
def send_mempool(self):
self.lastInv = []
self.send_message(msg_mempool())
class P2PMempoolTests(BitcoinTestFramework):
def __init__(self):
@ -65,20 +20,18 @@ class P2PMempoolTests(BitcoinTestFramework):
self.num_nodes = 2
def setup_network(self):
# Start a node with maxuploadtarget of 200 MB (/24h)
self.nodes = []
self.nodes.append(start_node(0, self.options.tmpdir, ["-peerbloomfilters=0"]))
self.nodes = [start_node(0, self.options.tmpdir, ["-peerbloomfilters=0"])]
def run_test(self):
#connect a mininode
aTestNode = TestNode()
aTestNode = NodeConnCB()
node = NodeConn('127.0.0.1', p2p_port(0), self.nodes[0], aTestNode)
aTestNode.add_connection(node)
NetworkThread().start()
aTestNode.wait_for_verack()
#request mempool
aTestNode.send_mempool()
aTestNode.send_message(msg_mempool())
aTestNode.wait_for_disconnect()
#mininode must be disconnected at this point

View File

@ -35,79 +35,22 @@ def get_virtual_size(witness_block):
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.ping_counter = 1
self.last_pong = msg_pong(0)
self.sleep_time = 0.05
self.getdataset = set()
self.last_reject = None
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 on_inv(self, conn, message):
self.last_inv = message
def on_block(self, conn, message):
self.last_block = message.block
self.last_block.calc_sha256()
def on_getdata(self, conn, message):
for inv in message.inv:
self.getdataset.add(inv.hash)
self.last_getdata = message
def on_getheaders(self, conn, message):
self.last_getheaders = message
def on_pong(self, conn, message):
self.last_pong = message
def on_reject(self, conn, message):
self.last_reject = message
# Syncing helpers
def sync(self, test_function, timeout=60):
while timeout > 0:
with mininode_lock:
if test_function():
return
time.sleep(self.sleep_time)
timeout -= self.sleep_time
raise AssertionError("Sync failed to complete")
def wait_for_block(self, blockhash, timeout=60):
test_function = lambda: self.last_block != None and self.last_block.sha256 == blockhash
self.sync(test_function, timeout)
return
def wait_for_getdata(self, timeout=60):
test_function = lambda: self.last_getdata != None
self.sync(test_function, timeout)
def wait_for_getheaders(self, timeout=60):
test_function = lambda: self.last_getheaders != None
self.sync(test_function, timeout)
def wait_for_inv(self, expected_inv, timeout=60):
test_function = lambda: self.last_inv != expected_inv
self.sync(test_function, timeout)
def announce_tx_and_wait_for_getdata(self, tx, timeout=60):
with mininode_lock:
self.last_getdata = None
self.last_message.pop("getdata", None)
self.send_message(msg_inv(inv=[CInv(1, tx.sha256)]))
self.wait_for_getdata(timeout)
return
def announce_block_and_wait_for_getdata(self, block, use_header, timeout=60):
with mininode_lock:
self.last_getdata = None
self.last_getheaders = None
self.last_message.pop("getdata", None)
self.last_message.pop("getheaders", None)
msg = msg_headers()
msg.headers = [ CBlockHeader(block) ]
if use_header:
@ -117,11 +60,10 @@ class TestNode(NodeConnCB):
self.wait_for_getheaders()
self.send_message(msg)
self.wait_for_getdata()
return
def announce_block(self, block, use_header):
with mininode_lock:
self.last_getdata = None
self.last_message.pop("getdata", None)
if use_header:
msg = msg_headers()
msg.headers = [ CBlockHeader(block) ]
@ -131,22 +73,22 @@ class TestNode(NodeConnCB):
def request_block(self, blockhash, inv_type, timeout=60):
with mininode_lock:
self.last_block = None
self.last_message.pop("block", None)
self.send_message(msg_getdata(inv=[CInv(inv_type, blockhash)]))
self.wait_for_block(blockhash, timeout)
return self.last_block
return self.last_message["block"].block
def test_transaction_acceptance(self, tx, with_witness, accepted, reason=None):
tx_message = msg_tx(tx)
if with_witness:
tx_message = msg_witness_tx(tx)
self.send_message(tx_message)
self.sync_with_ping(60)
self.sync_with_ping()
assert_equal(tx.hash in self.connection.rpc.getrawmempool(), accepted)
if (reason != None and not accepted):
# Check the rejection reason as well.
with mininode_lock:
assert_equal(self.last_reject.reason, reason)
assert_equal(self.last_message["reject"].reason, reason)
# Test whether a witness block had the correct effect on the tip
def test_witness_block(self, block, accepted, with_witness=True):
@ -154,10 +96,9 @@ class TestNode(NodeConnCB):
self.send_message(msg_witness_block(block))
else:
self.send_message(msg_block(block))
self.sync_with_ping(60)
self.sync_with_ping()
assert_equal(self.connection.rpc.getbestblockhash() == block.hash, accepted)
# Used to keep track of anyone-can-spend outputs that we can use in the tests
class UTXO(object):
def __init__(self, sha256, n, nValue):
@ -228,7 +169,7 @@ class SegWitTest(BitcoinTestFramework):
block = self.build_next_block(nVersion=1)
block.solve()
self.test_node.send_message(msg_block(block))
self.test_node.sync_with_ping(60) # make sure the block was processed
self.test_node.sync_with_ping() # make sure the block was processed
txid = block.vtx[0].sha256
self.nodes[0].generate(99) # let the block mature
@ -244,7 +185,7 @@ class SegWitTest(BitcoinTestFramework):
assert_equal(msg_tx(tx).serialize(), msg_witness_tx(tx).serialize())
self.test_node.send_message(msg_witness_tx(tx))
self.test_node.sync_with_ping(60) # make sure the tx was processed
self.test_node.sync_with_ping() # make sure the tx was processed
assert(tx.hash in self.nodes[0].getrawmempool())
# Save this transaction for later
self.utxo.append(UTXO(tx.sha256, 0, 49*100000000))
@ -279,12 +220,12 @@ class SegWitTest(BitcoinTestFramework):
# TODO: fix synchronization so we can test reject reason
# Right now, bitcoind delays sending reject messages for blocks
# until the future, making synchronization here difficult.
#assert_equal(self.test_node.last_reject.reason, "unexpected-witness")
#assert_equal(self.test_node.last_message["reject"].reason, "unexpected-witness")
# But it should not be permanently marked bad...
# Resend without witness information.
self.test_node.send_message(msg_block(block))
self.test_node.sync_with_ping(60)
self.test_node.sync_with_ping()
assert_equal(self.nodes[0].getbestblockhash(), block.hash)
sync_blocks(self.nodes)
@ -893,7 +834,7 @@ class SegWitTest(BitcoinTestFramework):
# Verify that if a peer doesn't set nServices to include NODE_WITNESS,
# the getdata is just for the non-witness portion.
self.old_node.announce_tx_and_wait_for_getdata(tx)
assert(self.old_node.last_getdata.inv[0].type == 1)
assert(self.old_node.last_message["getdata"].inv[0].type == 1)
# Since we haven't delivered the tx yet, inv'ing the same tx from
# a witness transaction ought not result in a getdata.
@ -1028,20 +969,20 @@ class SegWitTest(BitcoinTestFramework):
block1.solve()
self.test_node.announce_block_and_wait_for_getdata(block1, use_header=False)
assert(self.test_node.last_getdata.inv[0].type == blocktype)
assert(self.test_node.last_message["getdata"].inv[0].type == blocktype)
self.test_node.test_witness_block(block1, True)
block2 = self.build_next_block(nVersion=4)
block2.solve()
self.test_node.announce_block_and_wait_for_getdata(block2, use_header=True)
assert(self.test_node.last_getdata.inv[0].type == blocktype)
assert(self.test_node.last_message["getdata"].inv[0].type == blocktype)
self.test_node.test_witness_block(block2, True)
block3 = self.build_next_block(nVersion=(VB_TOP_BITS | (1<<15)))
block3.solve()
self.test_node.announce_block_and_wait_for_getdata(block3, use_header=True)
assert(self.test_node.last_getdata.inv[0].type == blocktype)
assert(self.test_node.last_message["getdata"].inv[0].type == blocktype)
self.test_node.test_witness_block(block3, True)
# Check that we can getdata for witness blocks or regular blocks,
@ -1250,9 +1191,9 @@ class SegWitTest(BitcoinTestFramework):
# Spending a higher version witness output is not allowed by policy,
# even with fRequireStandard=false.
self.test_node.test_transaction_acceptance(tx3, with_witness=True, accepted=False)
self.test_node.sync_with_ping(60)
self.test_node.sync_with_ping()
with mininode_lock:
assert(b"reserved for soft-fork upgrades" in self.test_node.last_reject.reason)
assert(b"reserved for soft-fork upgrades" in self.test_node.last_message["reject"].reason)
# Building a block with the transaction must be valid, however.
block = self.build_next_block()
@ -1380,7 +1321,7 @@ class SegWitTest(BitcoinTestFramework):
for i in range(NUM_TESTS):
# Ping regularly to keep the connection alive
if (not i % 100):
self.test_node.sync_with_ping(60)
self.test_node.sync_with_ping()
# Choose random number of inputs to use.
num_inputs = random.randint(1, 10)
# Create a slight bias for producing more utxos

View File

@ -28,20 +28,9 @@ from test_framework.test_framework import BitcoinTestFramework
from test_framework.util import *
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connected = False
self.received_version = False
def on_open(self, conn):
self.connected = True
def on_close(self, conn):
self.connected = False
def on_version(self, conn, message):
# Don't send a verack in response
self.received_version = True
pass
class TimeoutsTest(BitcoinTestFramework):
def __init__(self):
@ -83,7 +72,7 @@ class TimeoutsTest(BitcoinTestFramework):
sleep(30)
assert(self.no_verack_node.received_version)
assert "version" in self.no_verack_node.last_message
assert(self.no_verack_node.connected)
assert(self.no_version_node.connected)

View File

@ -24,28 +24,10 @@ WARN_UNKNOWN_RULES_MINED = "Unknown block versions being mined! It's possible un
WARN_UNKNOWN_RULES_ACTIVE = "unknown new rules activated (versionbit {})".format(VB_UNKNOWN_BIT)
VB_PATTERN = re.compile("^Warning.*versionbit")
# TestNode: bare-bones "peer". Used mostly as a conduit for a test to sending
# p2p messages to a node, generating the messages in the main testing logic.
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.connection = None
self.ping_counter = 1
self.last_pong = msg_pong()
def add_connection(self, conn):
self.connection = conn
def on_inv(self, conn, message):
pass
# Wrapper for the NodeConn's send_message function
def send_message(self, message):
self.connection.send_message(message)
def on_pong(self, conn, message):
self.last_pong = message
class VersionBitsWarningTest(BitcoinTestFramework):
def __init__(self):
super().__init__()

View File

@ -81,23 +81,17 @@ from test_framework.blocktools import create_block, create_coinbase
direct_fetch_response_time = 0.05
class BaseNode(NodeConnCB):
class TestNode(NodeConnCB):
def __init__(self):
super().__init__()
self.last_inv = None
self.last_headers = None
self.last_block = None
self.last_getdata = None
self.block_announced = False
self.last_getheaders = None
self.disconnected = False
self.last_blockhash_announced = None
def clear_last_announcement(self):
with mininode_lock:
self.block_announced = False
self.last_inv = None
self.last_headers = None
self.last_message.pop("inv", None)
self.last_message.pop("headers", None)
# Request data for a list of block hashes
def get_data(self, block_hashes):
@ -118,29 +112,17 @@ class BaseNode(NodeConnCB):
self.connection.send_message(msg)
def on_inv(self, conn, message):
self.last_inv = message
self.block_announced = True
self.last_blockhash_announced = message.inv[-1].hash
def on_headers(self, conn, message):
self.last_headers = message
if len(message.headers):
self.block_announced = True
message.headers[-1].calc_sha256()
self.last_blockhash_announced = message.headers[-1].sha256
def on_block(self, conn, message):
self.last_block = message.block
self.last_block.calc_sha256()
def on_getdata(self, conn, message):
self.last_getdata = message
def on_getheaders(self, conn, message):
self.last_getheaders = message
def on_close(self, conn):
self.disconnected = True
self.last_message["block"].calc_sha256()
# Test whether the last announcement we received had the
# right header or the right inv
@ -155,43 +137,27 @@ class BaseNode(NodeConnCB):
success = True
compare_inv = []
if self.last_inv != None:
compare_inv = [x.hash for x in self.last_inv.inv]
if "inv" in self.last_message:
compare_inv = [x.hash for x in self.last_message["inv"].inv]
if compare_inv != expect_inv:
success = False
hash_headers = []
if self.last_headers != None:
if "headers" in self.last_message:
# treat headers as a list of block hashes
hash_headers = [ x.sha256 for x in self.last_headers.headers ]
hash_headers = [ x.sha256 for x in self.last_message["headers"].headers ]
if hash_headers != expect_headers:
success = False
self.last_inv = None
self.last_headers = None
self.last_message.pop("inv", None)
self.last_message.pop("headers", None)
return success
# Syncing helpers
def wait_for_block(self, blockhash, timeout=60):
test_function = lambda: self.last_block != None and self.last_block.sha256 == blockhash
assert(wait_until(test_function, timeout=timeout))
return
def wait_for_getheaders(self, timeout=60):
test_function = lambda: self.last_getheaders != None
assert(wait_until(test_function, timeout=timeout))
return
def wait_for_getdata(self, hash_list, timeout=60):
if hash_list == []:
return
test_function = lambda: self.last_getdata != None and [x.hash for x in self.last_getdata.inv] == hash_list
assert(wait_until(test_function, timeout=timeout))
return
def wait_for_disconnect(self, timeout=60):
test_function = lambda: self.disconnected
test_function = lambda: "getdata" in self.last_message and [x.hash for x in self.last_message["getdata"].inv] == hash_list
assert(wait_until(test_function, timeout=timeout))
return
@ -210,17 +176,6 @@ class BaseNode(NodeConnCB):
getblocks_message.locator.vHave = locator
self.send_message(getblocks_message)
# InvNode: This peer should only ever receive inv's, because it doesn't ever send a
# "sendheaders" message.
class InvNode(BaseNode):
def __init__(self):
BaseNode.__init__(self)
# TestNode: This peer is the one we use for most of the testing.
class TestNode(BaseNode):
def __init__(self):
BaseNode.__init__(self)
class SendHeadersTest(BitcoinTestFramework):
def __init__(self):
super().__init__()
@ -260,7 +215,7 @@ class SendHeadersTest(BitcoinTestFramework):
def run_test(self):
# Setup the p2p connections and start up the network thread.
inv_node = InvNode()
inv_node = TestNode()
test_node = TestNode()
self.p2p_connections = [inv_node, test_node]
@ -368,8 +323,8 @@ class SendHeadersTest(BitcoinTestFramework):
inv_node.sync_with_ping()
# This block should not be announced to the inv node (since it also
# broadcast it)
assert_equal(inv_node.last_inv, None)
assert_equal(inv_node.last_headers, None)
assert "inv" not in inv_node.last_message
assert "headers" not in inv_node.last_message
tip = self.mine_blocks(1)
assert_equal(inv_node.check_last_announcement(inv=[tip]), True)
assert_equal(test_node.check_last_announcement(headers=[tip]), True)
@ -459,12 +414,12 @@ class SendHeadersTest(BitcoinTestFramework):
inv_node.send_message(msg_block(blocks[-1]))
inv_node.sync_with_ping() # Make sure blocks are processed
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
test_node.send_header_for_blocks(blocks)
test_node.sync_with_ping()
# should not have received any getdata messages
with mininode_lock:
assert_equal(test_node.last_getdata, None)
assert "getdata" not in test_node.last_message
# This time, direct fetch should work
blocks = []
@ -498,11 +453,11 @@ class SendHeadersTest(BitcoinTestFramework):
# Announcing one block on fork should not trigger direct fetch
# (less work than tip)
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
test_node.send_header_for_blocks(blocks[0:1])
test_node.sync_with_ping()
with mininode_lock:
assert_equal(test_node.last_getdata, None)
assert "getdata" not in test_node.last_message
# Announcing one more block on fork should trigger direct fetch for
# both blocks (same work as tip)
@ -517,11 +472,11 @@ class SendHeadersTest(BitcoinTestFramework):
test_node.wait_for_getdata([x.sha256 for x in blocks[2:16]], timeout=direct_fetch_response_time)
# Announcing 1 more header should not trigger any response
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
test_node.send_header_for_blocks(blocks[18:19])
test_node.sync_with_ping()
with mininode_lock:
assert_equal(test_node.last_getdata, None)
assert "getdata" not in test_node.last_message
self.log.info("Part 4: success!")
@ -532,7 +487,7 @@ class SendHeadersTest(BitcoinTestFramework):
# First we test that receipt of an unconnecting header doesn't prevent
# chain sync.
for i in range(10):
test_node.last_getdata = None
test_node.last_message.pop("getdata", None)
blocks = []
# Create two more blocks.
for j in range(2):
@ -543,7 +498,7 @@ class SendHeadersTest(BitcoinTestFramework):
height += 1
# Send the header of the second block -> this won't connect.
with mininode_lock:
test_node.last_getheaders = None
test_node.last_message.pop("getheaders", None)
test_node.send_header_for_blocks([blocks[1]])
test_node.wait_for_getheaders(timeout=1)
test_node.send_header_for_blocks(blocks)
@ -566,7 +521,7 @@ class SendHeadersTest(BitcoinTestFramework):
for i in range(1, MAX_UNCONNECTING_HEADERS):
# Send a header that doesn't connect, check that we get a getheaders.
with mininode_lock:
test_node.last_getheaders = None
test_node.last_message.pop("getheaders", None)
test_node.send_header_for_blocks([blocks[i]])
test_node.wait_for_getheaders(timeout=1)
@ -581,25 +536,21 @@ class SendHeadersTest(BitcoinTestFramework):
for i in range(5*MAX_UNCONNECTING_HEADERS - 1):
# Send a header that doesn't connect, check that we get a getheaders.
with mininode_lock:
test_node.last_getheaders = None
test_node.last_message.pop("getheaders", None)
test_node.send_header_for_blocks([blocks[i%len(blocks)]])
test_node.wait_for_getheaders(timeout=1)
# Eventually this stops working.
with mininode_lock:
self.last_getheaders = None
test_node.send_header_for_blocks([blocks[-1]])
# Should get disconnected
test_node.wait_for_disconnect()
with mininode_lock:
self.last_getheaders = True
self.log.info("Part 5: success!")
# Finally, check that the inv node never received a getdata request,
# throughout the test
assert_equal(inv_node.last_getdata, None)
assert "getdata" not in inv_node.last_message
if __name__ == '__main__':
SendHeadersTest().main()

View File

@ -192,7 +192,7 @@ class TestManager(object):
return wait_until(disconnected, timeout=10)
def wait_for_verack(self):
[node.wait_for_verack() for node in self.test_nodes]
return all(node.wait_for_verack() for node in self.test_nodes)
def wait_for_pings(self, counter):
def received_pongs():

View File

@ -1590,34 +1590,25 @@ class NodeConnCB(object):
# Message receiving helper methods
def sync(self, test_function, timeout=60):
while timeout > 0:
with mininode_lock:
if test_function():
return
time.sleep(0.05)
timeout -= 0.05
raise AssertionError("Sync failed to complete")
def wait_for_block(self, blockhash, timeout=60):
test_function = lambda: self.last_message.get("block") and self.last_message["block"].block.rehash() == blockhash
self.sync(test_function, timeout)
assert wait_until(test_function, timeout=timeout)
def wait_for_getdata(self, timeout=60):
test_function = lambda: self.last_message.get("getdata")
self.sync(test_function, timeout)
assert wait_until(test_function, timeout=timeout)
def wait_for_getheaders(self, timeout=60):
test_function = lambda: self.last_message.get("getheaders")
self.sync(test_function, timeout)
assert wait_until(test_function, timeout=timeout)
def wait_for_inv(self, expected_inv, timeout=60):
test_function = lambda: self.last_message.get("inv") and self.last_message["inv"] != expected_inv
self.sync(test_function, timeout)
assert wait_until(test_function, timeout=timeout)
def wait_for_verack(self, timeout=60):
test_function = lambda: self.message_count["verack"]
self.sync(test_function, timeout)
assert wait_until(test_function, timeout=timeout)
# Message sending helper functions
@ -1635,12 +1626,9 @@ class NodeConnCB(object):
def sync_with_ping(self, timeout=60):
self.send_message(msg_ping(nonce=self.ping_counter))
test_function = lambda: self.last_message.get("pong") and self.last_message["pong"].nonce == self.ping_counter
success = wait_until(test_function, timeout = timeout)
if not success:
logger.error("sync_with_ping failed!")
raise AssertionError("sync_with_ping failed!")
assert wait_until(test_function, timeout=timeout)
self.ping_counter += 1
return success
return True
# The actual NodeConn class
# This class provides an interface for a p2p connection to a specified node