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UUID vs sequential primary key in Python
Simulate and compare UUID vs sequential primary key generation in Python to understand trade-offs in ordering and uniqueness.
import uuid
import time
def create_record_with_uuid(name):
record_id = uuid.uuid4()
return {"id": record_id, "name": name}
def create_record_with_sequential_id(name, counter):
counter += 1
return {"id": counter, "name": name}
if __name__ == "__main__":
# Simulate users inserting records
sequ…Enforce TLS 1.2 Minimum in Python
Create an SSL context with a minimum TLS version of 1.2 to enforce secure connections.
import ssl
def get_min_tls_version():
context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
context.minimum_version = ssl.TLSVersion.TLSv1_2
return context.minimum_version
if __name__ == "__main__":
min_version = get_min_tls_version()
print(f"Minimum TLS version set to: {min_version.name} (value: {mi…How to Check Negotiated Cipher Suite in Python
Connect to a TLS server with Python's ssl module and print the negotiated protocol version and cipher suite details.
import ssl
import socket
def get_cipher_suites(hostname, port=443):
context = ssl.create_default_context()
context.set_ciphers("DEFAULT:@SECLEVEL=2")
with socket.create_connection((hostname, port), timeout=5) as sock:
with context.wrap_socket(sock, server_hostname=hostname) as ssock:
…How to Create Secure Session Cookies in Python with Secure, HttpOnly, and SameSite Flags
This code demonstrates how to create a secure session cookie using Python's stdlib, setting Secure, HttpOnly, and SameSite attributes to protect against common web vulnerabilities.
import http.cookies
import secrets
class SessionManager:
def __init__(self):
self.cookie = http.cookies.SimpleCookie()
def create_session_cookie(self, session_id=None):
session_id = session_id or secrets.token_hex(16)
self.cookie["session"] = session_id
self.cookie["session"][…How to Enforce a Strict Referrer Policy in Python
Validate HTTP headers to enforce a strict same-origin Referrer policy, accepting only origin-only URLs or absent Referer values.
import re
from unittest.mock import patch
def strict_referrer_policy(headers):
"""Return True if Referer header is absent or strictly same-origin."""
referer = headers.get("Referer")
if referer is None:
return True
# Strict-Origin-When-Cross-Origin allows same-origin full URL
# but here we…How to Generate PKCE Code Challenge in Python
This Python script generates a PKCE code verifier and its corresponding S256 code challenge for secure OAuth2 authorization flows.
import base64
import hashlib
import os
import secrets
import string
def generate_code_verifier(length=64):
alphabet = string.ascii_letters + string.digits + "-._~"
return "".join(secrets.choice(alphabet) for _ in range(length))
def generate_code_challenge(code_verifier, method="S256"):
if method == "S256…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 Mock a Permissions Policy in Python
A lightweight Python class that simulates a browser Permissions-Policy header by tracking allowed/ denied feature permissions with get, set, reset, and bulk operations.
class PermissionsPolicy:
def __init__(self):
self._features = {
"geolocation": "self",
"camera": "self",
"microphone": "self",
"payment": "self",
"usb": "self",
}
def get_feature_policy(self, feature):
return self._features.ge…How to Mock a TLS Certificate Rotation Schedule in Python
Simulate a TLS certificate rotation schedule with a Python class that tracks last and next rotation dates and decides when to rotate.
import datetime
import random
import time
class CertRotator:
def __init__(self, cert_name, rotation_days=30):
self.cert_name = cert_name
self.rotation_days = rotation_days
self.last_rotated = datetime.date.today() - datetime.timedelta(days=random.randint(10, 25))
self.next_rotatio…How to Revoke Tokens with a Blacklist Set in Python
A minimal TokenBlacklist class using a Python set to revoke, batch-revoke, check, and remove expired tokens for simple token invalidation.
import time
class TokenBlacklist:
def __init__(self):
self.blacklisted_tokens = set()
def revoke(self, token):
self.blacklisted_tokens.add(token)
print(f"Token {token} revoked. Blacklist size: {len(self.blacklisted_tokens)}")
def revoke_batch(self, tokens):
before = len(s…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 Set X-Frame-Options DENY in Flask with a Mock Response
Set the X-Frame-Options header to DENY in a Flask response to prevent clickjacking, and verify it with Flask's test client.
from flask import Flask, Response
app = Flask(__name__)
@app.route("/")
def index():
response = Response("Hello, World!")
response.headers["X-Frame-Options"] = "DENY"
return response
if __name__ == "__main__":
with app.test_client() as client:
resp = client.get("/")
print(resp.get_da…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…How to mock short TTL access tokens in Python
Simulate short-lived access tokens with a TTL, issue and validate them, and watch expiry behavior.
import time
import uuid
from datetime import datetime, timedelta
class AccessTokenManager:
def __init__(self, ttl_seconds=30):
self.ttl_seconds = ttl_seconds
self.tokens = {}
def issue_token(self):
token_id = uuid.uuid4().hex
expiry = datetime.now() + timedelta(seconds=self.t…Design a Data Helper for Beginners in Python
Build a beginner-friendly DataHelper class that loads, saves, appends, and summarizes JSON data with atomic file writes.
import json
from datetime import datetime
from pathlib import Path
class DataHelper:
"""A beginner-friendly helper for common data operations."""
def __init__(self, data=None, filepath=None):
self.data = data if data is not None else []
self.filepath = Path(filepath) if filepath else None
…Generate a Mock Artifact Version Tag in Python
Creates a mock build artifact version tag from a branch name and build number, with a date stamp.
import re
from datetime import datetime
def mock_version_tag(branch_name: str, build_number: int) -> str:
"""Generate a mock build artifact version tag from branch and build number."""
branch_slug = re.sub(r'[^a-zA-Z0-9]+', '-', branch_name).strip('-').lower()
date_part = datetime.utcnow().strftime('%Y%m%…Generate a docker-compose.yml with mock services in Python
Build a docker-compose.yml string from a Python dict of service names and images, then write it to a file.
import yaml
from pathlib import Path
def generate_mock_compose(services: dict) -> str:
compose = {
"version": "3.9",
"services": {}
}
for name, image in services.items():
compose["services"][name] = {
"image": image,
"container_name": f"mock-{name}",
…How to Attach an SBOM to a Release in Python (Mock)
A mock function that attaches a Software Bill of Materials (SBOM) to a GitHub-style release by counting its components and marking the upload as attached.
import json
from pathlib import Path
def attach_sbom_mock(sbom_path: Path, release_tag: str, artifact_name: str) -> dict:
"""Mock attaching an SBOM to a release, returning the simulated upload result."""
sbom = json.loads(sbom_path.read_text())
return {
"release_tag": release_tag,
"artifa…How to Build a Data Helper for Production Deployment in Python
Build a reusable DataHelper class that loads configs, validates required keys, normalizes string values, and logs schema details — a production-ready data processing pattern.
import json
from pathlib import Path
from typing import Any, Dict
class DataHelper:
"""Common data processing patterns for production deployment."""
def __init__(self, config_path: str | Path):
self.config_path = Path(config_path)
self.config = self._load_config()
def _load_confi…How to Build a Simple Data Helper Class in Python
A beginner-friendly DataHelper class that safely saves and loads JSON files with automatic directory creation, perfect for production-style file handling.
from pathlib import Path
import json
class DataHelper:
"""Simple production-style helper for loading and saving JSON data."""
def __init__(self, data_dir="data"):
self.data_dir = Path(data_dir)
self.data_dir.mkdir(exist_ok=True)
def save(self, filename, data):
filepath = self.da…How to Build a Simple Data Helper Class in Python
A beginner-friendly DataHelper class that stores Python dataclass objects as JSON records to disk, with load, add, and save methods.
import json
from dataclasses import dataclass, asdict
from pathlib import Path
@dataclass
class User:
name: str
age: int
email: str
class DataHelper:
def __init__(self, filepath: str = "data.json"):
self.filepath = Path(filepath)
self._data = self._load()
def _load(self) -> l…How to Build a Synthetic Monitor Mock in Python
Simulates a synthetic monitoring system in Python that collects latency samples, averages them, and reports service status as UP or DEGRADED.
import random
import time
from dataclasses import dataclass, field
from statistics import mean
@dataclass
class SyntheticMonitor:
service: str
endpoint: str
latency_ms: list[float] = field(default_factory=list)
def check(self) -> float:
latency = random.uniform(50.0, 250.0)
self.late…Browse by section
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