def test_replace_incoming_not_valid(self):
# Create a new blockchain, only has genesis
blockchain = Blockchain()
self.blockchain.chain[1].data = "Some bad data"
with self.assertRaises(ChainReplacementError):
# Try replacing chain with shorter chain
blockchain.replace(self.blockchain.chain)
def test_replace(self):
# Create a new blockchain, only has genesis
blockchain = Blockchain()
# Try replacing chain with longer chain
blockchain.replace(self.blockchain.chain)
# Assert that chain was replaced by longer one
self.assertEqual(blockchain.chain, self.blockchain.chain)
class TestBlockchain(TestCase):
def setUp(self):
self.blockchain = Blockchain()
for i in range(4):
self.blockchain.add_block(
[Transaction(Wallet(), "recipient_address", i).serialize()])
def test_instance(self):
self.assertEqual(Blockchain().genesis, Block.genesis())
def test_get_previous_block(self):
self.assertEqual(self.blockchain.previous_block,
self.blockchain.chain[-1])
def test_add_block(self):
self.assertEqual(len(self.blockchain.chain), 5)
self.blockchain.add_block("SHUcoin")
self.assertEqual(len(self.blockchain.chain), 6)
self.assertEqual(self.blockchain.previous_block.data, "SHUcoin")
def test_is_valid(self):
Blockchain.is_valid(self.blockchain.chain)
def test_is_valid_bad_genesis(self):
self.blockchain.chain[0].data = "Invalid data"
with self.assertRaises(GenesisError):
Blockchain.is_valid(self.blockchain.chain)
def test_replace(self):
# Create a new blockchain, only has genesis
blockchain = Blockchain()
# Try replacing chain with longer chain
blockchain.replace(self.blockchain.chain)
# Assert that chain was replaced by longer one
self.assertEqual(blockchain.chain, self.blockchain.chain)
def test_replace_incoming_not_longer(self):
# Create a new blockchain, only has genesis
incoming = Blockchain()
with self.assertRaisesRegex(
ChainReplacementError,
"Cannot replace. Incoming chain must be longer than local chain.",
):
# Try replacing chain with shorter chain
self.blockchain.replace(incoming.chain)
def test_replace_incoming_not_valid(self):
# Create a new blockchain, only has genesis
blockchain = Blockchain()
self.blockchain.chain[1].data = "Some bad data"
with self.assertRaises(ChainReplacementError):
# Try replacing chain with shorter chain
blockchain.replace(self.blockchain.chain)
def test_contains_valid_transactions(self):
Blockchain.contains_valid_transactions(self.blockchain.chain)
def test_contains_valid_transactions_duplicate_transaction(self):
transaction = Transaction(Wallet(), "recipient", 1).serialize()
self.blockchain.add_block([transaction, transaction])
with self.assertRaises(ContainsInvalidTransactionError):
Blockchain.contains_valid_transactions(self.blockchain.chain)
def test_contains_valid_transactions_duplicate_rewards(self):
self.blockchain.add_block([
Transaction.reward(Wallet()).serialize(),
Transaction.reward(Wallet()).serialize(),
])
# Block contains multiple reward transactions so we expect an exception
with self.assertRaises(ContainsInvalidTransactionError):
Blockchain.contains_valid_transactions(self.blockchain.chain)
def test_contains_valid_transactions_bad_transaction(self):
bad_transaction = Transaction(Wallet(), "recipient", 1)
# Use same transaction output but signed by wrong wallet
bad_transaction.input["signature"] = Wallet().sign(
bad_transaction.output)
self.blockchain.add_block([bad_transaction.serialize()])
with self.assertRaises(TransactionSignatureError):
Blockchain.contains_valid_transactions(self.blockchain.chain)
def test_contains_valid_transactions_bad_historic_balance(self):
wallet = Wallet()
bad_transaction = Transaction(wallet, "recipient", 1)
# Tamper with transaction, giving wallet a high amount
bad_transaction.output[wallet.address] = 1000
# Ensure input amount and transaction amount are still correct so validation doesn't fail at that point
bad_transaction.input["amount"] = 1001
# Re-sign
wallet.sign(bad_transaction.output)
self.blockchain.add_block([bad_transaction.serialize()])
with self.assertRaises(ContainsInvalidTransactionError):
Blockchain.contains_valid_transactions(self.blockchain.chain)
PORT = ROOT_PORT
# For convenience, it is easier to pass the 'peer' option when running the file from the command line. This may need to change in future.
if (
os.environ.get("PEER") == "1"
or os.environ.get("PEER") == "True"
or "peer" in sys.argv
):
PORT = random.randint(5001, 6000)
result = requests.get("http://localhost:{}/blockchain".format(ROOT_PORT))
result_blockchain = Blockchain.deserialize(result.json())
try:
# Synchronize with the blockchain
blockchain.replace(result_blockchain.chain)
print("Successfully synchronized the node.")
except ChainReplacementError as e:
print("Error synchronizing the node - {}".format(e.message))
if (
os.environ.get("SEED") == "1"
or os.environ.get("SEED") == "True"
or "seed" in sys.argv
):
for i in range(10):
blockchain.add_block(
[
Transaction(
Wallet(), Wallet().address, random.randint(2, 50)
).serialize(),