def test_block():
corner = Block(['Y', 'O', 'G'])
edge = Block(['Y', 'O'])
center1 = Block(['Y'])
center2 = Block(['Y', 'O', 'G', 'R'])
assert type(corner.stickers) is list
assert len(corner.stickers) == 3
assert corner.stickers == ['Y', 'O', 'G']
assert corner.block_type == 'corner'
assert type(edge.stickers) is list
assert len(edge.stickers) == 2
assert edge.stickers == ['Y', 'O']
assert edge.block_type == 'edge'
assert type(center1.stickers) is list
assert len(center1.stickers) == 1
assert center1.stickers == ['Y']
assert center1.block_type == 'center'
assert type(center2.stickers) is list
assert len(center2.stickers) == 4
assert center2.stickers == ['Y', 'O', 'G', 'R']
assert center2.block_type == 'center'
def create_genesis_block(self):
"""
A function to generate genesis block and appends it to
the chain. The block has index 0, previous_hash as 0, and
a valid hash.
"""
genesis_block = Block(0,[],0,'0')
genesis_block.hash = self._compute_hash()
self.chain.append(genesis_block)
def start(thread_name, ip_address, port):
import json
addr = (ip_address, port)
buf_size = 10240
# 소켓 생성 및 바인딩
tcp_socket = socket(AF_INET, SOCK_STREAM)
tcp_socket.bind(addr)
tcp_socket.listen(5)
while is_running:
# 요청이 있을경우 소켓과 송신자의 ip 주소 저장
receive_socket, sender_ip = tcp_socket.accept()
while is_running:
print("Receiving")
# 소켓으로부터 버퍼 사이즈씩 데이터 수신
data = receive_socket.recv(buf_size)
try:
# 수신된 데이터가 없는 경우
if (len(data) == 0):
break
print("data received...")
# json 형태의 데이터를 dict 타입으로 변경
data_json_obj = json.loads(data)
# Transaction을 받은 경우
if data_json_obj['type'] == 'T':
print("Received transaction")
print(data_json_obj)
# dict 데이터로부터 transaction 객체 생성
tx = Transaction().from_json(data_json_obj)
# transaction 추가
transaction.add_transaction(tx)
elif data_json_obj['type'] == 'B':
print("block received...")
# 기존 transacion 삭제
transaction.remove_all()
#블록 추가
received_block = Block().from_json(data_json_obj)
append_block(received_block)
except:
print("recv error...")
traceback.print_exc()
break
tcp_socket.close()
receive_socket.close()
def create_block(): transactions = transaction.get_transactions() # transaction이 없을 경우 block을 생성하지 않음 if len(transactions) == 0: return # 내 node 가 가지고 있는 마지막 블럭 last_block = block.get_last_block() # transaction JSON 문자열로 변환 transactions_str = list(map(lambda x: x.to_json(), transactions)) # transaction으로부터 merkle root 생성 merkle_root = merkle_tree(transactions_str) # block 정보에 merkle root 할당 block_info = merkle_root # block 새로 생성 _block = Block() # 마지막 block이 있는 경우 if last_block: # block 정보에 마지막 블럭의 해쉬를 더함 block_info += last_block.block_hash # 새로 생성한 block에 이전 block 정보 저장 _block.prev_block_hash = last_block.block_hash _block.prev_block_id = last_block.block_id # 작업 증명을 통해 nonce값과 hash 결과 생성 hash_result, nonce = proof_of_work(block_info, diff_bits=5) # block 정보 _block.block_hash = hash_result _block.nonce = nonce _block.block_info = block_info _block.time_stamp = datetime.datetime.now() # 내 node 에 block 저장 block.create_block(_block) # 내 node가 가지고 있는 transaction 삭제 transaction.remove_all() # 나머지 node에게 block 전송 sender.send_to_all_node((_block.to_json()), except_my_node=True)
def verify_and_add_block():
block_data = request.get_json()
block = Block(block_data["index"],
block_data["transactions"],
block_data["timestamp"],
block_data["previous_hash"],
block_data["nonce"])
proof = block_data['hash']
added = blockchain.add_block(block, proof)
if not added:
return "The block was discarded by the node", 400
return "Block added to the chain", 201
def create_chain_from_dump(chain_dump):
generated_blockchain = Blockchain()
generated_blockchain.create_genesis_block()
for idx, block_data in enumerate(chain_dump):
if idx == 0:
continue # skip genesis block
block = Block(block_data["index"],
block_data["transactions"],
block_data["timestamp"],
block_data["previous_hash"],
block_data["nonce"])
proof = block_data['hash']
added = generated_blockchain.add_block(block, proof)
if not added:
raise Exception("The chain dump is tampered!!")
return generated_blockchain
def mine(self):
"""
This function serves as an interface to add the pending
transactions to the blockchain by adding them to the block
and figuring out Proof Of Work.
"""
if not self.unconfirmed_transactions:
return False
#last block of chain
last_block = self.last_block
new_block = Block(index=last_block.index + 1,
transactions=self.unconfirmed_transactions,
timestamp=time.time(),
previous_hash=last_block.hash)
proof = self.proof_of_work(new_block)
self.add_block(new_block, proof)
self.unconfirmed_transactions = []
return True
def start(thread_name, ip_address, port):
import json
addr = (ip_address, port)
buf_size = 1024
# 소켓 생성 및 바인딩
tcp_socket = socket(AF_INET, SOCK_STREAM)
tcp_socket.bind(addr)
tcp_socket.listen(5)
while is_running:
# 요청이 있을 경우 소켓과 송신자의 ip 주소 저장
receive_socket, sender_ip = tcp_socket.accept()
while is_running:
log.write("Receiving")
# 소켓으로부터 버퍼 사이즈씩 데이터 수신
data = receive_socket.recv(buf_size)
try:
# 수신된 데이터가 없는 경우
if len(data) == 0:
break
# json 형태의 데이터를 dict 타입으로 변경
data_json_obj = json.loads(data)
# Transaction을 받은 경우
if data_json_obj['type'] == 'T':
log.write("Receiving a transaction")
verify_msg = data_json_obj['time_stamp'] + data_json_obj[
'message']
if key.verify_signature(data_json_obj['pub_key'],
data_json_obj['signature'],
verify_msg) is True:
log.write("Transaction is valid")
tx = Transaction().from_json(data_json_obj)
transaction.add_transaction(tx)
else:
log.write("Transaction is invalid")
# 블록을 수신한 경우
elif data_json_obj['type'] == 'B':
# 기존의 트랜잭션 삭제
transaction.remove_all()
# 블록 생성
received_block = Block().from_json(data_json_obj)
# 블록 저장
create_block(received_block)
except:
traceback.print_exc()
break
tcp_socket.close()
receive_socket.close()
def __init__(self):
Block.__init__(self,0,[],0,'0')
self.unconfirmed_transactions = []
self.chain = []
def create_block():
diff_bits = 5
transactions = transaction.get_transactions()
# transaction이 없을 경우 block을 생성하지 않음
if (len(transactions) == 0):
print("No transactions...")
return
# 내 node가 가지고 있는 마지막 블럭
last_block = block.get_last_block()
#transaction JSON 문자열로 변환
transactions_str = []
for tx in transactions:
transactions_str.append(tx.to_json())
# transaction 으로부터 merkle root 생성
merkle_root = merkle_tree(transactions_str)
# block 새로 생성
_block = Block()
# 마지막 블록이 있는 경우
if last_block:
# last bock 에 대한 정보 저장
_block.prev_block_id = last_block.block_id
_block.prev_block_hash = last_block.block_hash
# 작업 증명을 위해 nonce값과 결과 생성
_block.block_id = last_block.block_id + 1
_block.merkle_root = merkle_root
_block.difficulty = diff_bits
block_header = _block.getheader_json()
hash_result, nonce = proof_of_work(block_header, diff_bits)
# block 정보
_block.block_hash = hash_result
_block.nonce = nonce
_block.tx_list = transactions_str
# 내 node에 block 저장
block.append_block(_block)
# 내 node가 가지고 있는 transaction 삭제
transaction.remove_all()
# 나머지 node에게 block 전송
sender.send_to_all_node((_block.to_json()), except_my_node=True)
def __init__(self):
Block.__init__(self, 0, [], 0, '0')