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[pre-commit.ci] auto fixes from pre-commit.com hooks

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pre-commit-ci[bot] 2024-10-03 09:49:33 +00:00
parent f5459b8083
commit 95732058fb
1 changed files with 24 additions and 7 deletions
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31
blockchain/PoWAlgorithm.py
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@ -22,6 +22,7 @@ The algorithm implements the Proof of Work (PoW) consensus mechanism used in blo
import hashlib import hashlib
import time import time
class Block: class Block:
def __init__(self, index, previous_hash, transactions, timestamp, difficulty): def __init__(self, index, previous_hash, transactions, timestamp, difficulty):
self.index = index self.index = index
@ -35,7 +36,7 @@ class Block:
def compute_hash(self): def compute_hash(self):
""" """
Generates the hash of the block content. Generates the hash of the block content.
Combines index, previous hash, transactions, timestamp, and nonce into a string, Combines index, previous hash, transactions, timestamp, and nonce into a string,
which is then hashed using SHA-256. which is then hashed using SHA-256.
""" """
block_string = f"{self.index}{self.previous_hash}{self.transactions}{self.timestamp}{self.nonce}" block_string = f"{self.index}{self.previous_hash}{self.transactions}{self.timestamp}{self.nonce}"
@ -46,13 +47,16 @@ class Block:
Performs Proof of Work by adjusting the nonce until a valid hash is found. Performs Proof of Work by adjusting the nonce until a valid hash is found.
A valid hash has the required number of leading zeros based on the difficulty level. A valid hash has the required number of leading zeros based on the difficulty level.
""" """
target = '0' * self.difficulty # Target hash should start with 'difficulty' number of zeros target = (
while self.hash[:self.difficulty] != target: "0" * self.difficulty
) # Target hash should start with 'difficulty' number of zeros
while self.hash[: self.difficulty] != target:
self.nonce += 1 self.nonce += 1
self.hash = self.compute_hash() self.hash = self.compute_hash()
print(f"Block mined with nonce {self.nonce}, hash: {self.hash}") print(f"Block mined with nonce {self.nonce}, hash: {self.hash}")
class Blockchain: class Blockchain:
def __init__(self, difficulty): def __init__(self, difficulty):
self.chain = [] self.chain = []
@ -72,13 +76,19 @@ class Blockchain:
Adds a new block to the blockchain after performing Proof of Work. Adds a new block to the blockchain after performing Proof of Work.
""" """
previous_block = self.chain[-1] previous_block = self.chain[-1]
new_block = Block(len(self.chain), previous_block.hash, transactions, time.time(), self.difficulty) new_block = Block(
len(self.chain),
previous_block.hash,
transactions,
time.time(),
self.difficulty,
)
new_block.mine_block() new_block.mine_block()
self.chain.append(new_block) self.chain.append(new_block)
def is_chain_valid(self): def is_chain_valid(self):
""" """
Verifies the integrity of the blockchain by ensuring each block's previous hash matches Verifies the integrity of the blockchain by ensuring each block's previous hash matches
and that all blocks meet the Proof of Work requirement. and that all blocks meet the Proof of Work requirement.
""" """
for i in range(1, len(self.chain)): for i in range(1, len(self.chain)):
@ -95,8 +105,10 @@ class Blockchain:
return True return True
# Test cases # Test cases
def test_blockchain(): def test_blockchain():
""" """
Test cases for the Blockchain proof of work algorithm. Test cases for the Blockchain proof of work algorithm.
@ -112,11 +124,16 @@ def test_blockchain():
assert blockchain.is_chain_valid() == True, "Blockchain should be valid" assert blockchain.is_chain_valid() == True, "Blockchain should be valid"
# Tamper with the blockchain and check validation # Tamper with the blockchain and check validation
blockchain.chain[1].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering the transaction blockchain.chain[
assert blockchain.is_chain_valid() == False, "Blockchain should be invalid due to tampering" 1
].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering the transaction
assert (
blockchain.is_chain_valid() == False
), "Blockchain should be invalid due to tampering"
print("All test cases passed.") print("All test cases passed.")
if __name__ == "__main__": if __name__ == "__main__":
test_blockchain() test_blockchain()