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How to Redact Secrets from Log Messages in Python
Build a lightweight RedactingFormatter class that replaces sensitive tokens like passwords and API keys with [REDACTED] before log messages are printed.
class RedactingFormatter:
def __init__(self, secrets):
self.secrets = secrets
def redact(self, message):
for secret in self.secrets:
message = message.replace(secret, "[REDACTED]")
return message
def format(self, record):
message = record["message"]
ret…How to Implement MapReduce Word Count in Python Using a Dict
Simulate a MapReduce word count pipeline in Python with a mock dict, splitting text into words, shuffling, and reducing to frequency counts.
def map_reduce_word_count(text: str) -> dict:
"""Simulate a MapReduce pipeline to count word frequencies."""
# MAP phase: split into words and emit (word, 1) pairs
mapped = []
for word in text.lower().split():
# Clean word of punctuation
clean_word = ''.join(char for char in word if cha…How to Hash Passwords Securely in Python
Hash passwords with PBKDF2, random salts, and constant pepper, plus generate secure API keys using Python's stdlib.
import hashlib
import secrets
import time
import hmac
def hash_password(password: str, salt: str = None, pepper: str = "static-pepper") -> dict:
"""Hash a password with a random salt and constant pepper."""
if salt is None:
salt = secrets.token_hex(16)
salted = f"{pepper}{salt}{password}"
dig…How to Hash Passwords with bcrypt in Python
Hash a plaintext password with bcrypt using a randomly generated salt, then verify a plaintext attempt against the stored hash.
import bcrypt
def hash_password(password: str) -> str:
"""Hash a password using bcrypt with a generated salt."""
salt = bcrypt.gensalt()
return bcrypt.hashpw(password.encode("utf-8"), salt).decode("utf-8")
def check_password(password: str, hashed: str) -> bool:
"""Verify a plaintext password against …How to Hash and Verify Passwords in Python
Hash passwords securely with PBKDF2-SHA256 and verify them using a constant-time comparison.
import hashlib
import hmac
import secrets
from typing import Tuple
def hash_password(password: str, salt: str = None) -> Tuple[str, str]:
"""Hash a password with a random salt using PBKDF2-SHA256."""
salt = salt or secrets.token_hex(16)
hashed = hashlib.pbkdf2_hmac(
"sha256", password.encode("utf…How to Salt Passwords per User in Python
Hash each user's password with a unique random salt using hashlib, and verify logins with timing-safe comparison.
import hashlib
import secrets
def hash_password(password: str, salt: str | None = None) -> tuple[str, str]:
"""Hash a password with a random salt (or provided salt).
Returns:
(salt_hex, password_hash_hex)
"""
if salt is None:
salt = secrets.token_hex(16)
salted = (salt + password)…How to Verify Passwords in Constant Time in Python
Use hmac.compare_digest to verify passwords in constant time, preventing timing attacks that could reveal password length or character positions.
import hmac
import time
# Mock of a constant-time password comparison (prevents timing attacks)
def verify_password(stored_password: str, supplied_password: str) -> bool:
# hmac.compare_digest runs in constant time (for a given length)
return hmac.compare_digest(stored_password.encode(), supplied_password.enc…Browse by section
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