def test_crypto_hash():
"""
Test that produced hash is equal the actual value
"""
assert crypto_hash(
'foo'
) == 'b2213295d564916f89a6a42455567c87c3f480fcd7a1c15e220f17d7169a790b'
def mine_block(last_block, data):
"""
Mine a block based on the given last_block and data. Until a block hash
is found that meets the leading 0's proof of work requirement.
"""
timestamp = time.time_ns()
last_hash = last_block.hash
difficulty = Block.adjust_difficulty(last_block, timestamp)
nonce = 0
hash = crypto_hash(timestamp, last_hash, data, difficulty, nonce)
while hex_to_binary(hash)[0:difficulty] != '0' * difficulty:
nonce += 1
timestamp = time.time_ns()
hash = crypto_hash(timestamp, last_hash, data, difficulty, nonce)
return Block(timestamp, last_hash, hash, data, difficulty, nonce)
def main():
number = 888
hex_number = hex(number)[2:]
print(f'hex_number: {hex_number}')
binary_number = hex_to_binary(hex_number)
print(f'binary_number: {binary_number}')
original_number = int(binary_number, 2)
print(f'original_number: {original_number}')
hex_to_binary_crypto_hash = hex_to_binary(crypto_hash('test-data'))
print(f'hex_to_binary_crypto_hash: {hex_to_binary_crypto_hash}')
def is_valid_block(last_block, block):
"""
Validate block by enforcing the following rules:
- the block must have the proper last_hash reference.
- the block must meet the proof of work requirement.
- the difficulty must only adjust by 1.
- the block hash must be a valid combination of the block fields.
"""
if block.last_hash != last_block.hash:
raise Exception('last_hash must be correct')
if hex_to_binary(
block.hash)[0:block.difficulty] != '0' * block.difficulty:
raise Exception('The proof of requirement was not met.')
if abs(last_block.difficulty - block.difficulty) > 1:
raise Exception('The block difficulty must only adjust by 1.')
reconstructed_hash = crypto_hash(block.timestamp, block.last_hash,
block.data, block.nonce,
block.difficulty)
if block.hash != reconstructed_hash:
raise Exception('The block hash must be correct.')
def test_crypto_hash_order():
"""
test that crypto_hash function outputs same hash
for different arguments order.
"""
assert crypto_hash(1, [2], 'three') == crypto_hash('three', 1, [2])