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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 10:10:05 +00:00
parent 9a6fcd5417
commit 6a7b49d95e
1 changed files with 29 additions and 15 deletions
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44
blockchain/pow_algorithm.py
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@ -9,6 +9,7 @@
import hashlib
import time
class Block:
def __init__(
self,
@ -16,7 +17,7 @@ class Block:
previous_hash: str,
transactions: str,
timestamp: float,
difficulty: int
difficulty: int,
) -> None:
"""
Initializes a Block object with the specified parameters.
@ -42,7 +43,7 @@ class Block:
Generates the hash of the block content.
Combines index, previous hash, transactions, timestamp, and nonce into
a string, which is then hashed using SHA-256.
Returns:
- str: The hash of the block.
"""
@ -57,17 +58,20 @@ 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.
Returns:
- None
"""
target = '0' * self.difficulty # Target hash should start with 'difficulty' zeros
while self.hash[:self.difficulty] != target:
target = (
"0" * self.difficulty
) # Target hash should start with 'difficulty' 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: int) -> None:
"""
@ -75,7 +79,7 @@ class Blockchain:
Parameters:
- difficulty (int): The difficulty level for mining blocks in this blockchain.
Returns:
- None
"""
@ -86,7 +90,7 @@ class Blockchain:
def create_genesis_block(self) -> None:
"""
Creates the first block in the blockchain (the Genesis block).
Returns:
- None
"""
@ -100,21 +104,24 @@ class Blockchain:
Parameters:
- transactions (str): The list of transactions to be added in the new block.
Returns:
- None
"""
previous_block = self.chain[-1]
new_block = Block(
len(self.chain), previous_block.hash, transactions, time.time(),
self.difficulty
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) -> bool:
"""
Verifies the integrity of the blockchain by ensuring each block's previous
Verifies the integrity of the blockchain by ensuring each block's previous
hash matches and that all blocks meet the Proof of Work requirement.
Returns:
@ -134,15 +141,17 @@ class Blockchain:
return True
# Test cases
## Test Case 1: Blockchain Initialization and Genesis Block
# This test verifies if the blockchain is correctly initialized with a Genesis block
# and if the block is successfully mined.
def test_blockchain() -> None:
"""
Test cases for the Blockchain proof of work algorithm.
Returns:
- None
"""
@ -162,14 +171,19 @@ def test_blockchain() -> None:
## Test Case 4: Tampering with the blockchain
# This test simulates tampering with the blockchain and checks that the validation
# correctly detects the tampering.
blockchain.chain[1].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering
assert not blockchain.is_chain_valid(), "Blockchain should be invalid due to tampering"
blockchain.chain[
1
].transactions = "Transaction 1: Alice pays Bob 50 BTC" # Tampering
assert (
not blockchain.is_chain_valid()
), "Blockchain should be invalid due to tampering"
## Test Case 5: Correct blockchain validation
# This test checks if the blockchain becomes invalid after tampering and verifies
# if the PoW still holds after tampering is done.
print("All test cases passed.")
if __name__ == "__main__":
test_blockchain()