def validate(self, data):
# Check for extra data
extra_data = self.context['request'].data.get('extra_data')
if not data.get('extra_data') and extra_data:
data['extra_data'] = b64decode(extra_data)
# Build the transaction
tx = UnconfirmedTransaction(**data)
# Verify the hash
tx.hash = tx.calculate_hash()
if tx.hash != data['hash']:
raise serializers.ValidationError('Invalid hash')
# Verify the signature
if not verify(tx.hash, tx.from_account, tx.signature):
raise serializers.ValidationError('Bad signature')
data['transaction'] = tx
# Validate the transaction
active_block = Block.get_active_block()
if not validate_transaction(
active_block.get_balances(),
tx,
prev_block=active_block,
):
raise serializers.ValidationError('Transaction was not accepted.')
return data
def mine_block():
logger.debug('Checking for sync locks...')
if SyncLock.objects.count():
logger.debug("Looks like we're syncing, canceling mine_block call.")
return
logger.debug('Mining new block...')
broadcast = None
with transaction.atomic():
# Get the active block
active_block = Block.get_active_block()
logger.debug(f'{active_block.id} is the active block.')
# Collect the unconfirmed transactions
unconfirmed = UnconfirmedTransaction.objects.all()
logger.debug(f'{len(unconfirmed)} unconfirmed transactions found.')
# Prune invalid transactions
transactions = prune_invalid_transactions(active_block, unconfirmed)
logger.debug(f'{len(transactions)} transactions after pruning.')
# Convert the unconfirmed transactions and add the block reward
transactions = [u.to_transaction() for u in transactions]
transactions.insert(0, Transaction.create_block_reward())
# Set up the block
block = Block(
previous_block=active_block,
depth=active_block.depth + 1,
miner=settings.MINER_PUBLIC_KEY,
extra_data=settings.BLOCK_EXTRA_DATA,
time=now(),
)
block.set_merkle_root(transactions)
block.set_balances(
apply_transactions_to_balances(
transactions,
active_block.get_balances(),
))
block.set_hash()
block.sign()
# Validate the block and transactions
if validate_block(block, transactions):
# Save the block
block.save(transactions)
UnconfirmedTransaction.objects.all().delete()
broadcast = block
logger.info(f'Block {block.id} successfully mined.')
else:
logger.info('Failed to mine block - validation error!')
if broadcast:
from boocoin.p2p import broadcast_block
broadcast_block(broadcast)
def is_time_to_mine():
"""
Returns whether or not there are either at least 10 unconfirmed
transactions, or it has been at least 10 minutes since the last block was
mined.
"""
active_block = Block.get_active_block()
minutes_passed = (now() - active_block.time).total_seconds() / 60
if UnconfirmedTransaction.objects.count() >= 10 or minutes_passed > 10:
return True
return False
def check_for_block():
# Get the active block
active_block = Block.get_active_block()
# Calculate how many minutes it has been since that block
minutes_passed = (now() - active_block.time).total_seconds() / 60
logger.debug(f'Minutes passed since last block: {minutes_passed}')
# Mine a new block if it has been 10 minutes
if minutes_passed >= 10:
logger.info('10 minutes passed, mining new block...')
mine_block()
def get(self, request):
before = request.GET.get('before')
if before:
from_block = get_object_or_404(Block, id=before)
else:
from_block = Block.get_active_block()
ids = []
for i in range(100):
ids.append(from_block.id)
if from_block.previous_block:
from_block = from_block.previous_block
else:
break
return Response(ids)
def get(self, request):
return Response(Block.get_active_block().depth + 1)