def mine():
transactions = get_transactions()
transactions = [Transaction.from_dict(x) for x in transactions]
last_block = get_last_block()
block = Block(last_block['id'] + 1, transactions, 0)
while not block.get_hash(last_block['hash']).startswith('0000'):
block.nonce += 1
block.set_hash(block.get_hash(last_block['hash']))
r = requests.post(b_url + '/add_block', json=block.to_dict())
return r.text
def create_gift_coin(self, blockchain):
"""
This method creates a new coin for the new client
"""
# Get address of the client
hash_public_key = self.hash_pubkey()
coin_gift_tx_input = TransactionInput(prev_tx="1" * 64,
pk_spender="1" * 64,
signature=bytes(
"\x11" * 64,
encoding="utf-8"))
coin_gift_tx_output = TransactionOutput(
value=100, hash_pubkey_recipient=hash_public_key)
coin_gift_tx = Transaction(tx_input=coin_gift_tx_input,
tx_output=coin_gift_tx_output)
transactions = [coin_gift_tx]
nonce = 0
new_block = None
while True:
if len(blockchain.blocks) != 0:
hash_prev_block = blockchain.blocks[len(blockchain.blocks) -
1].get_hash()
new_block = Block(transactions, nonce, hash_prev_block)
else:
new_block = Block(transactions=transactions,
nonce=nonce,
prev_block_hash="0" * 64)
if new_block.get_hash().startswith("0" * blockchain.difficulty):
print("Nonce found:", nonce)
break
nonce += 1
print(coin_gift_tx.serialize())
message = "\x12" + new_block.serialize()
self.socket.sendall(message.encode('utf-8'))
def handler(self, connection_handler, ip_port_tuple):
try:
while True:
#data = connection_handler.recv(self.byte_size)
data = recv_timeout(connection_handler)
# Check if the peer wants to disconnect
for connection in self.connections:
if data and data == 'cmd_show_peers':
connection.sendall(
('---' + str(self.peers)).encode('utf-8'))
elif data and data[0:1] == "\x12":
print("==> New mined block.")
new_block_info = data[1:]
new_block = Block(serialization=new_block_info)
in_blockchain = False
for block in self.blockchain.blocks:
if new_block.equal_blocks(block):
print(
"==> This block is already mined and is in your blockchain. It will not be added to server blockchain"
)
in_blockchain = True
break
if not in_blockchain:
print("\t", new_block.__dict__)
print("\tNew Block Hash:", new_block.get_hash())
self.blockchain.add_block(new_block)
update_blockchain_file(self.blockchain.serialize())
connection.sendall(data.encode("utf-8"))
elif data:
connection.sendall(data.encode("utf-8"))
except ConnectionResetError:
print("==> " + str(ip_port_tuple) + " disconnected")
self.connections.remove(connection_handler)
connection_handler.close()
self.peers.remove(ip_port_tuple)
self.send_peers()
def __init__(self, address):
"""
Initialization method for Client class
Convention:
0x10 - New Transaction
0x11 - New peers
0x12 - New mined block
0x13 - Blockchain
"""
self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# Make the connection
self.socket.connect((address, 5000))
self.byte_size = 1024
self.peers = []
print('==> Connected to server.')
self.generate_key_pair()
client_listener_thread = threading.Thread(target=self.send_message)
client_listener_thread.start()
while True:
try:
data = self.receive_message()
if data[0:1] == '\x11':
print('==> Got peers.')
update_peers(data[1:])
elif data[0:1] == '\x10':
print('==> New transaction.')
transaction_info = data[1:]
transaction = Transaction(serialization=transaction_info)
# Mining block
result = mine_block(transaction=transaction,
blockchain=self.blockchain,
miner_address=self.hash_pubkey())
if result["status"]:
message = "\x12" + result["new_block"].serialize()
print("==> Sending new mined block")
self.socket.sendall(message.encode("utf-8"))
else:
print(
"==> Invalid transaction. The block have not been mined"
)
elif data[0:1] == '\x13':
print('==> Blockchain downloaded.')
blockchain_info = data[1:]
self.blockchain = Blockchain(serialization=blockchain_info)
update_blockchain_file(self.blockchain.serialize())
elif data[0:1] == '\x12':
print('==> New mined block.')
block_info = data[1:]
new_block = Block(serialization=block_info)
in_blockchain = False
for block in self.blockchain.blocks:
if new_block.equal_blocks(block):
print(
"==> This block is already mined and is in your blockchain. It will not be added"
)
in_blockchain = True
break
if not in_blockchain:
print("\t", new_block.__dict__)
print("\tNew Block Hash:", new_block.get_hash())
self.blockchain.add_block(new_block)
update_blockchain_file(self.blockchain.serialize())
elif data != "":
print("[#] " + data)
except ConnectionError as error:
print("==> Server disconnected. ")
print('\t--' + str(error))
break
