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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 time
class Block:
def __init__(self, index, previous_hash, transactions, timestamp, difficulty):
self.index = index
@ -35,7 +36,7 @@ class Block:
def compute_hash(self):
"""
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.
"""
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.
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
while self.hash[:self.difficulty] != target:
target = (
"0" * self.difficulty
) # Target hash should start with 'difficulty' number of zeros
while self.hash[: self.difficulty] != target:
self.nonce += 1
self.hash = self.compute_hash()
print(f"Block mined with nonce {self.nonce}, hash: {self.hash}")
class Blockchain:
def __init__(self, difficulty):
self.chain = []
@ -72,13 +76,19 @@ class Blockchain:
Adds a new block to the blockchain after performing Proof of Work.
"""
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()
self.chain.append(new_block)
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.
"""
for i in range(1, len(self.chain)):
@ -95,8 +105,10 @@ class Blockchain:
return True
# Test cases
def test_blockchain():
"""
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"
# Tamper with the blockchain and check validation
blockchain.chain[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"
blockchain.chain[
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.")
if __name__ == "__main__":
test_blockchain()