def create_block(cls):
last_block = Block.last()
previous_hash = last_block.block_id
proof_of_work = ProofOfWork(previous_hash, 10)
proof_result = proof_of_work.prove()
if not proof_result.isValid():
raise Exception('fail proof')
transactions = UnconfirmedTransactionPool.transactions.copy()
UnconfirmedTransactionPool.transactions.clear()
block_number = len(Block.list()) + 1
block = Block.build(
block_number = block_number,
version = "1",
previous_block_hash = previous_hash,
timestamp = datetime.now().timestamp(),
merkle_root = "", # TODO
difficulty_target = 10,
nonce = proof_result.nonce,
transactions = transactions
)
for tx in transactions:
tx.block_id = block.block_id
Block.create_block(block)
db.session.commit()
transaction = cls._create_transaction_to_miner()
return block, proof_result, transaction
def seed(cls):
timestamp = 0
block = Block.build(block_number=1,
version='1',
previous_block_hash='1',
timestamp=1,
merkle_root='',
difficulty_target=10,
nonce=1)
transaction = Transaction.build(block_id='1',
locktime=0,
timestamp=timestamp)
transaction_output = TransactionOutput.build(
transaction_id='1',
amount=10000000000000000000,
sender_address='coinbase',
recipient_address=
'-----BEGIN PUBLIC KEY-----\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAznjoHvzCJtQcIYd3yj7v\ngwaPlyiG6U/Qlw1G89n0bNt5anvRe+e2eKzvpy98aj6ShGu7hARE9SxAFA9bIHCB\nqdAyPnrUaw7qGkeZNPHBByHe9prJSn0ZwBtfySOSbzdetO5aAwvLj5qMudW2PDz1\n5mP2taGOvXqNnbcH78ZHQLvF6G+SbwuLHU5LEDSZlcy+CnvPqD67cg+QmJLneVmQ\nfOBtbFHz3yDQghNrHWa+UCspUMHVGsDG6OEK7MSpPieY6TzBEYQWsikosQ+V0zBN\nrSCADe3GBcJ7XzafM/gb+gzJ1eP78F1sA6Ja4ZtqInqN406PwerAXaUJa2twW652\n9wIDAQAB\n-----END PUBLIC KEY-----',
timestamp=timestamp)
db.session.add(block)
db.session.add(transaction)
db.session.add(transaction_output)
db.session.commit()
def _create_block(cls):
last_block = Blockchain.fetch_last_block()
previous_hash = last_block.block_id
block_number = Blockchain.fetch_block_count() + 1
proof_of_work = ProofOfWork(previous_hash,
last_block.difficulty_target)
proof_result = proof_of_work.prove()
proof_result.assert_valid()
transactions = UnconfirmedTxPool.transactions.copy()
UnconfirmedTxPool.transactions.clear()
target_transactions = Blockchain.search_new_transactions(transactions)
block = Block.build(
block_number=block_number,
previous_block_hash=previous_hash,
timestamp=datetime.now().timestamp(),
merkle_root="", # TODO
difficulty_target=last_block.difficulty_target,
nonce=proof_result.nonce,
transactions=target_transactions)
last_block = Blockchain.fetch_last_block()
if last_block.block_id != block.previous_block_hash:
print('lost mining', block.block_id)
raise LoseMiningException()
Blockchain.create_block(block)
print('block created', block.block_id)
print('current block number', block.block_number)
return block, proof_result
class Blockchain:
blocks = [
Block.build(
block_number=1,
previous_block_hash="1",
timestamp=0,
merkle_root="",
difficulty_target=20,
nonce=0,
transactions=[
Transaction.build(
timestamp=1,
tx_inputs=[],
tx_outputs=[
TransactionOutput.build(
amount=1000000000,
sender_address=COINBASE_ADDRESS,
recipient_address=
"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAznjoHvzCJtQcIYd3yj7vgwaPlyiG6U/Qlw1G89n0bNt5anvRe+e2eKzvpy98aj6ShGu7hARE9SxAFA9bIHCBqdAyPnrUaw7qGkeZNPHBByHe9prJSn0ZwBtfySOSbzdetO5aAwvLj5qMudW2PDz15mP2taGOvXqNnbcH78ZHQLvF6G+SbwuLHU5LEDSZlcy+CnvPqD67cg+QmJLneVmQfOBtbFHz3yDQghNrHWa+UCspUMHVGsDG6OEK7MSpPieY6TzBEYQWsikosQ+V0zBNrSCADe3GBcJ7XzafM/gb+gzJ1eP78F1sA6Ja4ZtqInqN406PwerAXaUJa2twW6529wIDAQAB",
timestamp=1)
]),
Transaction.build(
timestamp=1,
tx_inputs=[],
tx_outputs=[
TransactionOutput.build(
amount=200000000,
sender_address=COINBASE_ADDRESS,
recipient_address=
"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAznjoHvzCJtQcIYd3yj7vgwaPlyiG6U/Qlw1G89n0bNt5anvRe+e2eKzvpy98aj6ShGu7hARE9SxAFA9bIHCBqdAyPnrUaw7qGkeZNPHBByHe9prJSn0ZwBtfySOSbzdetO5aAwvLj5qMudW2PDz15mP2taGOvXqNnbcH78ZHQLvF6G+SbwuLHU5LEDSZlcy+CnvPqD67cg+QmJLneVmQfOBtbFHz3yDQghNrHWa+UCspUMHVGsDG6OEK7MSpPieY6TzBEYQWsikosQ+V0zBNrSCADe3GBcJ7XzafM/gb+gzJ1eP78F1sA6Ja4ZtqInqN406PwerAXaUJa2twW6529wIDAQAB",
timestamp=1)
]),
Transaction.build(
timestamp=1,
tx_inputs=[],
tx_outputs=[
TransactionOutput.build(
amount=300003,
sender_address=COINBASE_ADDRESS,
recipient_address=
"MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAznjoHvzCJtQcIYd3yj7vgwaPlyiG6U/Qlw1G89n0bNt5anvRe+e2eKzvpy98aj6ShGu7hARE9SxAFA9bIHCBqdAyPnrUaw7qGkeZNPHBByHe9prJSn0ZwBtfySOSbzdetO5aAwvLj5qMudW2PDz15mP2taGOvXqNnbcH78ZHQLvF6G+SbwuLHU5LEDSZlcy+CnvPqD67cg+QmJLneVmQfOBtbFHz3yDQghNrHWa+UCspUMHVGsDG6OEK7MSpPieY6TzBEYQWsikosQ+V0zBNrSCADe3GBcJ7XzafM/gb+gzJ1eP78F1sA6Ja4ZtqInqN406PwerAXaUJa2twW6529wIDAQAB",
timestamp=1)
]),
])
]
@classmethod
def fetch_all_blocks(cls):
return cls.blocks
@classmethod
def fetch_block_count(cls):
return len(cls.blocks)
@classmethod
def fetch_last_block(cls):
return cls.blocks[-1]
@classmethod
def fetch_unspent_tx_outputs_by_tx_output_ids(cls, tx_output_ids):
blocks = cls.blocks
if len(blocks) == 0:
return []
transactions = reduce(
add, list(map(lambda block: block.transactions, blocks)))
if len(transactions) == 0:
return []
tx_outputs = reduce(add,
list(map(lambda tx: tx.tx_outputs, transactions)))
tx_inputs = reduce(add, list(map(lambda tx: tx.tx_inputs,
transactions)))
spent_tx_output_ids = list(
map(lambda tx_i: tx_i.transaction_output_id, tx_inputs))
unspent_tx_outputs = list(
filter(
lambda tx_o: tx_o.transaction_output_id not in
spent_tx_output_ids, tx_outputs))
return list(
filter(lambda tx_o: tx_o.transaction_output_id in tx_output_ids,
unspent_tx_outputs))
@classmethod
def fetch_unspent_tx_outputs_by_address(cls, address):
blocks = cls.blocks
if len(blocks) == 0:
return []
transactions = reduce(
add, list(map(lambda block: block.transactions, blocks)))
if len(transactions) == 0:
return []
tx_outputs = reduce(add,
list(map(lambda tx: tx.tx_outputs, transactions)))
tx_inputs = reduce(add, list(map(lambda tx: tx.tx_inputs,
transactions)))
spent_tx_output_ids = list(
map(lambda tx_i: tx_i.transaction_output_id, tx_inputs))
return list(
filter(
lambda tx_o: tx_o.recipient_address == address and tx_o.
transaction_output_id not in spent_tx_output_ids, tx_outputs))
@classmethod
def create_block(cls, block):
cls.blocks.append(block)
@classmethod
def search_new_transactions(cls, transactions):
transactions_in_chain = reduce(
add, list(map(lambda block: block.transactions, cls.blocks)))
return list(
filter(lambda tx: tx not in transactions_in_chain, transactions))
@classmethod
def delete_block(cls, deleting_block):
cls.blocks.remove(deleting_block)
@classmethod
def find_block(cls, block_id):
blocks = list(
filter(lambda block: block.block_id == block_id, cls.blocks))
if len(blocks) == 0:
return None
return blocks[0]