class Validator():
def __init__(self, genesis, key, network, env, time_offset=5):
# Create a chain object
self.chain = Chain(genesis, env=env)
# Use the validator's time as the chain's time
self.chain.time = lambda: self.get_timestamp()
# My private key
self.key = key
# My address
self.address = privtoaddr(key)
# My randao
self.randao = RandaoManager(sha3(self.key))
# Pointer to the test p2p network
self.network = network
# Record of objects already received and processed
self.received_objects = {}
# The minimum eligible timestamp given a particular number of skips
self.next_skip_count = 0
self.next_skip_timestamp = 0
# This validator's indices in the state
self.indices = None
# Is this validator active?
self.active = False
# Code that verifies signatures from this validator
self.validation_code = generate_validation_code(privtoaddr(key))
# Parents that this validator has already built a block on
self.used_parents = {}
# This validator's clock offset (for testing purposes)
self.time_offset = random.randrange(time_offset) - (time_offset // 2)
# Determine the epoch length
self.epoch_length = self.call_casper('getEpochLength')
# Give this validator a unique ID
self.id = len(ids)
ids.append(self.id)
self.find_my_indices()
self.cached_head = self.chain.head_hash
def call_casper(self, fun, args=[]):
return call_casper(self.chain.state, fun, args)
def find_my_indices(self):
epoch = self.chain.state.block_number // self.epoch_length
print 'Finding indices for epoch %d' % epoch, self.call_casper(
'getEpoch')
for i in range(len(validator_sizes)):
valcount = self.call_casper('getHistoricalValidatorCount',
[epoch, i])
print i, valcount, self.call_casper('getHistoricalValidatorCount',
[0, i])
for j in range(valcount):
valcode = self.call_casper('getValidationCode', [i, j])
print(valcode, self.validation_code)
if valcode == self.validation_code:
self.indices = i, j
start = self.call_casper('getStartEpoch', [i, j])
end = self.call_casper('getEndEpoch', [i, j])
if start <= epoch < end:
self.active = True
self.next_skip_count = 0
self.next_skip_timestamp = get_timestamp(
self.chain, self.next_skip_count)
print 'In current validator set at (%d, %d)' % (i, j)
return
else:
self.indices = None
self.active = False
self.next_skip_count, self.next_skip_timestamp = 0, 0
print 'Registered at (%d, %d) but not in current set' % (
i, j)
return
self.indices = None
self.active = False
self.next_skip_count, self.next_skip_timestamp = 0, 0
print 'Not in current validator set'
def get_uncles(self):
anc = self.chain.get_block(
self.chain.get_blockhash_by_number(self.chain.state.block_number -
CHECK_FOR_UNCLES_BACK))
if anc:
descendants = self.chain.get_descendants(anc)
else:
descendants = self.chain.get_descendants(
self.chain.db.get('GENESIS_HASH'))
potential_uncles = [
x for x in descendants
if x not in self.chain and isinstance(x, Block)
]
uncles = [
x.header for x in potential_uncles if not call_casper(
self.chain.state, 'isDunkleIncluded', [x.header.hash])
]
return uncles
def get_timestamp(self):
return int(self.network.time * 0.01) + self.time_offset
def on_receive(self, obj):
if isinstance(obj, list):
for _obj in obj:
self.on_receive(_obj)
return
if obj.hash in self.received_objects:
return
if isinstance(obj, Block):
print 'Receiving block', obj
assert obj.hash not in self.chain
block_success = self.chain.add_block(obj)
self.network.broadcast(self, obj)
self.network.broadcast(self, ChildRequest(obj.header.hash))
self.update_head()
elif isinstance(obj, Transaction):
if self.chain.add_transaction(obj):
self.network.broadcast(self, obj)
self.received_objects[obj.hash] = True
for x in self.chain.get_chain():
assert x.hash in self.received_objects
def tick(self):
# Try to create a block
# Conditions:
# (i) you are an active validator,
# (ii) you have not yet made a block with this parent
if self.indices and self.chain.head_hash not in self.used_parents:
t = self.get_timestamp()
# Is it early enough to create the block?
if t >= self.next_skip_timestamp and (
not self.chain.head
or t > self.chain.head.header.timestamp):
# Wrong validator; in this case, just wait for the next skip count
if not check_skips(self.chain, self.indices,
self.next_skip_count):
self.next_skip_count += 1
self.next_skip_timestamp = get_timestamp(
self.chain, self.next_skip_count)
# print 'Incrementing proposed timestamp for block %d to %d' % \
# (self.chain.head.header.number + 1 if self.chain.head else 0, self.next_skip_timestamp)
return
self.used_parents[self.chain.head_hash] = True
# Simulated 15% chance of validator failure to make a block
if random.random() > 0.999:
print 'Simulating validator failure, block %d not created' % (
self.chain.head.header.number +
1 if self.chain.head else 0)
return
# Make the block, make sure it's valid
pre_dunkle_count = call_casper(self.chain.state,
'getTotalDunklesIncluded', [])
dunkle_txs = []
for i, u in enumerate(self.get_uncles()[:4]):
start_nonce = self.chain.state.get_nonce(self.address)
txdata = casper_ct.encode('includeDunkle', [rlp.encode(u)])
dunkle_txs.append(
Transaction(start_nonce + i, 0, 650000,
self.chain.config['CASPER_ADDR'], 0,
txdata).sign(self.key))
for dtx in dunkle_txs[::-1]:
self.chain.add_transaction(dtx, force=True)
blk = make_block(self.chain, self.key, self.randao,
self.indices, self.next_skip_count)
global global_block_counter
global_block_counter += 1
for dtx in dunkle_txs:
assert dtx in blk.transactions, (dtx, blk.transactions)
print 'made block with timestamp %d and %d dunkles' % (
blk.timestamp, len(dunkle_txs))
assert blk.timestamp >= self.next_skip_timestamp
assert self.chain.add_block(blk)
self.update_head()
post_dunkle_count = call_casper(self.chain.state,
'getTotalDunklesIncluded', [])
assert post_dunkle_count - pre_dunkle_count == len(dunkle_txs)
self.received_objects[blk.hash] = True
print 'Validator %d making block %d (%s)' % (
self.id, blk.header.number,
blk.header.hash[:8].encode('hex'))
self.network.broadcast(self, blk)
# Sometimes we received blocks too early or out of order;
# run an occasional loop that processes these
if random.random() < 0.02:
self.chain.process_time_queue()
self.chain.process_parent_queue()
self.update_head()
def update_head(self):
if self.cached_head == self.chain.head_hash:
return
self.cached_head = self.chain.head_hash
if self.chain.state.block_number % self.epoch_length == 0:
self.find_my_indices()
if self.indices:
self.next_skip_count = 0
self.next_skip_timestamp = get_timestamp(self.chain,
self.next_skip_count)
print 'Head changed: %s, will attempt creating a block at %d' % (
self.chain.head_hash.encode('hex'), self.next_skip_timestamp)
def withdraw(self, gasprice=20 * 10**9):
h = sha3(b'withdrawwithdrawwithdrawwithdraw')
v, r, s = ecsign(h, self.key)
sigdata = encode_int32(v) + encode_int32(r) + encode_int32(s)
txdata = casper_ct.encode('startWithdrawal',
[self.indices[0], self.indices[1], sigdata])
tx = Transaction(self.chain.state.get_nonce(self.address), gasprice,
650000, self.chain.config['CASPER_ADDR'], 0,
txdata).sign(self.key)
self.chain.add_transaction(tx)
self.network.broadcast(self, tx)
print 'Withdrawing!'
class Validator():
def __init__(self, genesis, key, network, env, time_offset=5):
# Create a chain object
self.chain = Chain(genesis, env=env)
# Use the validator's time as the chain's time
self.chain.time = lambda: self.get_timestamp()
# My private key
self.key = key
# My address
self.address = privtoaddr(key)
# My randao
self.randao = RandaoManager(sha3(self.key))
# Pointer to the test p2p network
self.network = network
# Record of objects already received and processed
self.received_objects = {}
# The minimum eligible timestamp given a particular number of skips
self.next_skip_count = 0
self.next_skip_timestamp = 0
# This validator's indices in the state
self.indices = None
# Code that verifies signatures from this validator
self.validation_code = generate_validation_code(privtoaddr(key))
# Parents that this validator has already built a block on
self.used_parents = {}
# This validator's clock offset (for testing purposes)
self.time_offset = random.randrange(time_offset) - (time_offset // 2)
# Give this validator a unique ID
self.id = len(ids)
ids.append(self.id)
self.find_my_indices()
self.cached_head = self.chain.head_hash
def find_my_indices(self):
for i in range(len(validatorSizes)):
epoch = self.chain.state.block_number // EPOCH_LENGTH
valcount = call_casper(self.chain.state, 'getHistoricalValidatorCount', [epoch, i])
for j in range(valcount):
valcode = call_casper(self.chain.state, 'getValidationCode', [i, j])
if valcode == self.validation_code:
self.indices = i, j
self.next_skip_count = 0
self.next_skip_timestamp = get_timestamp(self.chain, self.next_skip_count)
print 'In current validator set at (%d, %d)' % (i, j)
return
self.indices = None
self.next_skip_count, self.next_skip_timestamp = 0, 0
print 'Not in current validator set'
def get_uncles(self):
anc = self.chain.get_block(self.chain.get_blockhash_by_number(self.chain.state.block_number - CHECK_FOR_UNCLES_BACK))
if anc:
descendants = self.chain.get_descendants(anc)
else:
descendants = self.chain.get_descendants(self.chain.db.get('GENESIS_HASH'))
potential_uncles = [x for x in descendants if x not in self.chain and isinstance(x, Block)]
uncles = [x.header for x in potential_uncles if not call_casper(self.chain.state, 'isDunkleIncluded', [x.header.hash])]
return uncles
def get_timestamp(self):
return int(self.network.time * 0.01) + self.time_offset
def on_receive(self, obj):
if isinstance(obj, list):
for _obj in obj:
self.on_receive(_obj)
return
if obj.hash in self.received_objects:
return
if isinstance(obj, Block):
print 'Receiving block', obj
assert obj.hash not in self.chain, (self.received_objects, obj.hash, [x.hash for x in self.chain.get_chain()])
block_success = self.chain.add_block(obj)
self.network.broadcast(self, obj)
self.network.broadcast(self, ChildRequest(obj.header.hash))
self.update_head()
elif isinstance(obj, Transaction):
self.chain.add_transaction(obj)
self.received_objects[obj.hash] = True
for x in self.chain.get_chain():
assert x.hash in self.received_objects
def tick(self):
# Try to create a block
# Conditions:
# (i) you are an active validator,
# (ii) you have not yet made a block with this parent
if self.indices and self.chain.head_hash not in self.used_parents:
t = self.get_timestamp()
# Is it early enough to create the block?
if t >= self.next_skip_timestamp and (not self.chain.head or t > self.chain.head.header.timestamp):
print 'creating', t, self.next_skip_timestamp
# Wrong validator; in this case, just wait for the next skip count
if not check_skips(self.chain, self.indices, self.next_skip_count):
self.next_skip_count += 1
self.next_skip_timestamp = get_timestamp(self.chain, self.next_skip_count)
print 'Incrementing proposed timestamp for block %d to %d' % \
(self.chain.head.header.number + 1 if self.chain.head else 0, self.next_skip_timestamp)
return
self.used_parents[self.chain.head_hash] = True
# Simulated 15% chance of validator failure to make a block
if random.random() > 0.999:
print 'Simulating validator failure, block %d not created' % (self.chain.head.header.number + 1 if self.chain.head else 0)
return
# Make the block, make sure it's valid
pre_dunkle_count = call_casper(self.chain.state, 'getTotalDunklesIncluded', [])
dunkle_txs = []
for i, u in enumerate(self.get_uncles()[:4]):
start_nonce = self.chain.state.get_nonce(self.address)
print 'start_nonce', start_nonce
txdata = casper_ct.encode('includeDunkle', [rlp.encode(u)])
dunkle_txs.append(Transaction(start_nonce + i, 0, 650000, self.chain.config['CASPER_ADDR'], 0, txdata).sign(self.key))
for dtx in dunkle_txs[::-1]:
self.chain.add_transaction(dtx, force=True)
blk = make_block(self.chain, self.key, self.randao, self.indices, self.next_skip_count)
global global_block_counter
global_block_counter += 1
for dtx in dunkle_txs:
assert dtx in blk.transactions, (dtx, blk.transactions)
print 'made block with timestamp %d and %d dunkles' % (blk.timestamp, len(dunkle_txs))
assert blk.timestamp >= self.next_skip_timestamp
assert self.chain.add_block(blk)
self.update_head()
post_dunkle_count = call_casper(self.chain.state, 'getTotalDunklesIncluded', [])
assert post_dunkle_count - pre_dunkle_count == len(dunkle_txs)
self.received_objects[blk.hash] = True
print 'Validator %d making block %d (%s)' % (self.id, blk.header.number, blk.header.hash[:8].encode('hex'))
self.network.broadcast(self, blk)
# Sometimes we received blocks too early or out of order;
# run an occasional loop that processes these
if random.random() < 0.02:
self.chain.process_time_queue()
self.chain.process_parent_queue()
self.update_head()
def update_head(self):
if self.cached_head == self.chain.head_hash:
return
self.cached_head = self.chain.head_hash
if self.chain.state.block_number % EPOCH_LENGTH == 0:
self.find_my_indices()
if self.indices:
self.next_skip_count = 0
self.next_skip_timestamp = get_timestamp(self.chain, self.next_skip_count)
print 'Head changed: %s, will attempt creating a block at %d' % (self.chain.head_hash.encode('hex'), self.next_skip_timestamp)
