def initialize_users():
# Need to create a datastructure that stores the user
users = []
transactions = []
for i in range(utils.number_of_users):
coinsList = []
newUser = User(i)
for j in range(10):
cID = str(i * 10 + j)
signature = sign_message(scrooge_private, str(cID))
encoded = base64.b64encode(signature)
no_bytes = encoded.decode('utf-8')
coin_dict = {}
coin_dict[cID] = no_bytes
newUser.add_coin(coin_dict)
transaction = {}
transaction['previous_transaction'] = None
transaction['sender'] = 'scrooge'
transaction['receiver'] = newUser.user_id
transaction['coin_id'] = json.dumps(coin_dict)
transactions.append(transaction)
utils.printLog(
"User " + str(i) + "\n" +
str(newUser.private_key.public_key().public_bytes(
encoding=serialization.Encoding.PEM,
format=serialization.PublicFormat.SubjectPublicKeyInfo)))
utils.printLog("10 coins")
users.append(newUser)
return users, transactions
def create_block(print_transactions=False):
block = OrderedDict()
for index in range(10):
item = queue[index]
for key in item:
if (print_transactions):
utils.printLog("Adding to block Transaction ID: ", key)
block[key] = item[key]
block['previous_block'] = utils.previous_block
return block
def create_transaction(self):
number = self.user_id
if(len(self.coins)>0):
while(number==self.user_id):
number = random.randint(0, utils.number_of_users-1)
transaction = {}
coin_entry = random.randint(0, len(self.coins)-1)
cID = self.coins[coin_entry]
transaction['previous_transaction'] = utils.find_previous_transaction(cID)
transaction['sender'] = self.user_id
transaction['receiver'] = number
transaction['coin_id'] = cID
dictionary, t_hash = utils.sign_and_hash('transaction', transaction, self.private_key)
utils.printLog("Creating Transaction ID: ",t_hash, " User ",transaction['sender'], " Sending CoinID ",next(iter(transaction['coin_id']))," to User ",transaction['receiver'], " Previous transaction ID ",transaction['previous_transaction'])
return dictionary
return None
def check_double(transaction, index):
get_cID = transaction['coin_id']
get_sender = transaction['sender']
for index2, signed_transaction in enumerate(queue):
for key in signed_transaction:
q_transaction = signed_transaction[key]['transaction']
if (get_cID == q_transaction['coin_id']
and get_sender == q_transaction['sender']
and index > index2):
utils.printLog("Double Spending, User ", get_sender,
" Tried to pay coin ID", get_cID, "to Users ",
transaction['receiver'], " and ",
q_transaction['receiver'])
queue.remove(queue[index])
index -= 1
return True
return False
users, init_transactions = initialize_users()
# for transaction in init_transactions:
for transaction in init_transactions:
dictionary, _ = sign_and_hash("transaction", transaction,
scrooge_private)
queue.append(dictionary)
if (len(queue) == 10):
block = create_block()
queue = []
signed_block, _ = sign_and_hash("block", block, scrooge_private)
for key in signed_block:
utils.blockchain[key] = signed_block[key]
while True:
if is_pressed(' '):
utils.printLog("Created ", len(utils.blockchain), " blocks")
SystemExit(0)
break
random_user_id = random.randint(0, utils.number_of_users - 1)
transaction = users[random_user_id].create_transaction()
if (transaction is not None):
queue.append(transaction)
if (len(queue) >= 10):
doChecks(check_double_spending=True)
if (len(queue) >= 10):
utils.printLog("Creating a block")
block = create_block(print_transactions=True)
queue = queue[10:]
signed_block, _ = sign_and_hash("block", block, scrooge_private)
for key in signed_block:
utils.blockchain[key] = signed_block[key]