def receive_block(cls, block, proof_result, sender_node_url, tx_to_miner):
last_block = Blockchain.fetch_last_block()
if not proof_result.is_valid():
raise InvalidReceivedBlockException()
if last_block.block_id != block.previous_block_hash:
if last_block.block_number < block.block_number:
print('resolving conflicting...')
cls._resolve_conflicts(sender_node_url)
else:
print('win conflict')
raise TooShortReceivedBlockException()
if last_block.block_id == block.previous_block_hash:
Blockchain.create_block(block)
UnconfirmedTxPool.transactions.clear()
UnconfirmedTxPool.create_transaction(tx_to_miner)
def fetch_unspent_tx_outputs_by_address(cls, request):
address = request.get_json()['address']
unspent_tx_outputs_in_blockchain = Blockchain.fetch_unspent_tx_outputs_by_address(
address)
result_tx_outputs = list(
filter(
lambda tx_o: tx_o.transaction_output_id not in
UnconfirmedTxPool.list_spent_tx_output_ids(),
unspent_tx_outputs_in_blockchain))
return jsonify(result_tx_outputs), 200
def _resolve_conflicts(cls, send_node_url):
json = requests.get(send_node_url + '/blocks').json()
send_node_blocks = list(
map(lambda block_dict: decode_block(block_dict), json))
my_node_blocks = Blockchain.fetch_all_blocks()
forked_block_number = cls._search_forked_block_number(
send_node_blocks, my_node_blocks)
deleting_blocks = list(
filter(lambda block: block.block_number > forked_block_number,
my_node_blocks))
adding_blocks = list(
filter(lambda block: block.block_number > forked_block_number,
send_node_blocks))
for deleting_block in deleting_blocks:
Blockchain.delete_block(deleting_block)
for adding_block in adding_blocks:
Blockchain.create_block(adding_block)
def create_transaction(cls, tx_request):
# 使用としているトランザクションアウトプットIDが既に未承認のトランザクションアウトプットIDに含まれていたら例外を投げる
spent_tx_output_ids_in_unconfirmed_tx_pool = UnconfirmedTxPool.list_spent_tx_output_ids()
tx_request.assert_unspent_tx_output_ids(spent_tx_output_ids_in_unconfirmed_tx_pool)
unspent_tx_outputs_in_blockchain = Blockchain.fetch_unspent_tx_outputs_by_tx_output_ids(
tx_request.get_requesting_tx_output_ids())
# 今回使用しようとしているトランザクションインプットを算出
tx_inputs = tx_request.get_tx_inputs(unspent_tx_outputs_in_blockchain)
TransactionInput.verify_tx_inputs(tx_inputs, tx_request.sender_address)
transaction = Transaction.build_with_tx_outputs(
timestamp = tx_request.timestamp,
tx_inputs = tx_inputs,
request_amount = tx_request.amount,
sender_address = tx_request.sender_address,
recipient_address = tx_request.recipient_address
)
UnconfirmedTxPool.transactions.append(transaction)
return transaction
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
def assert_new_block(cls, block_id):
block = Blockchain.find_block(block_id)
if block is not None:
raise DuplicatedBlockException()
return
def fetch_all_blocks(cls):
return jsonify(Blockchain.fetch_all_blocks()), 200