def test_transactions_validate_invalid_rewards():
miner_wallet = Wallet()
reward_transaction = Transactions.transaction_reward(miner_wallet)
reward_transaction.output[miner_wallet.address] = 100
reward_transaction.output['recp1'] = 100
with pytest.raises(Exception, match="Invalid transaction reward"):
Transactions.verify_transaction(reward_transaction)
def is_chain_transaction_valid(chain):
"""
Method to verify if each of the transactions in the chain is valid.
Transaction is valid if:
1. Each transation appears only once in the blockchain.
2. There is only one reward transaction.
3. The transaction is valid.
"""
transaction_ids = set()
for index, block in enumerate(chain):
if index == 0:
continue
has_reward_transaction = False
for transaction_json in block.data:
transaction = Transactions.from_json(transaction_json)
if transaction.input == MINING_REWARD_INPUT:
if has_reward_transaction is True:
raise Exception(
"Transaction with id %s has multiple rewards" %
(transaction.id))
has_reward_transaction = True
else:
#calculate historical balance using a historical balance
historical_chain = chain[:index]
historical_blockchain = Blockchain()
historical_blockchain.chain = historical_chain
#get the balance amount of the address
balance = Wallet.calculate_balance(
historical_blockchain, transaction.input['address'])
if balance != transaction.input['amount']:
raise Exception(
"Transaction id %s did not have the correct balance"
% (transaction.id))
if transaction.id in transaction_ids:
raise Exception("Transaction with id %s is not unique" %
(transaction.id))
transaction_ids.add(transaction.id)
Transactions.verify_transaction(transaction)
def test_transactions_validate_reward():
miner_wallet = Wallet()
reward_transaction = Transactions.transaction_reward(miner_wallet)
Transactions.verify_transaction(reward_transaction)
def test_verify_transactions_invalid_signature():
wallet = Wallet()
transactions = Transactions(wallet, 'recp1', 100)
transactions.input['signature'] = Wallet().sign(transactions.output)
with pytest.raises(Exception, match="Invalid Signature"):
Transactions.verify_transaction(transactions)
def test_verify_transactions_output_values_wrong():
wallet = Wallet()
transactions = Transactions(wallet, 'recp1', 100)
transactions.input['amount'] = 78
with pytest.raises(Exception, match="Invalid output values"):
Transactions.verify_transaction(transactions)
def test_verify_transactions():
wallet = Wallet()
transactions = Transactions(wallet, 'recp1', 100)
Transactions.verify_transaction(transactions)