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How to Create a Mock Docker Registry Auth Token Server in Python
Build a mock Docker Registry token authentication server that issues signed JWT-like tokens for push and pull access using Python's standard library.
import base64
import hashlib
import hmac
import json
import time
from http.server import BaseHTTPRequestHandler, HTTPServer
class TokenAuthHandler(BaseHTTPRequestHandler):
"""Mock Docker Registry token authentication server."""
SECRET_KEY = b"mock-secret-key"
def generate_token(self, username: str, pas…How to Mock OAuth2 Bearer Token Auth Middleware in Python
Create a simple OAuth2 bearer token authentication middleware that verifies signed tokens and enforces scope-based access control.
import hmac
import time
import base64
import json
from functools import wraps
VALID_TOKENS = {"test_token_123": {"user": "alice", "scope": "read:posts"}}
def generate_token(username: str) -> str:
payload = {"user": username, "iat": int(time.time())}
encoded = base64.urlsafe_b64encode(json.dumps(payload).enc…How to Mock mTLS Between Services in Python
Simulate mutual TLS authentication between two services using Python's ssl module with self-signed certificates.
import ssl
import socket
import threading
import tempfile
from pathlib import Path
import subprocess
def create_test_cert(cert_path: Path, key_path: Path, common_name: str = "localhost"):
"""Generate a self-signed certificate using openssl."""
subprocess.run([
"openssl", "req", "-x509", "-newkey", "rs…JWT Service-to-Service Authentication Mock in Python
Create and verify HS256 JWTs for service-to-service authentication without external libraries.
import hashlib
import hmac
import base64
import json
import time
class JWTMock:
"""Minimal JWT service-to-service mock using HS256."""
def __init__(self, secret):
self.secret = secret.encode()
@staticmethod
def _b64url_encode(data):
return base64.urlsafe_b64encode(data).rstr…Zero Trust Service Auth Mock in Python
A simple HMAC-based token issuance and validation mock that enforces zero trust between microservices.
import hmac
import hashlib
import json
import time
class ZeroTrustAuth:
def __init__(self, secret_key):
self.secret_key = secret_key
self.service_tokens = {}
def issue_token(self, service_name, ttl=300):
payload = {
"service": service_name,
"issued_at": int(tim…ChaCha20-Poly1305 mock in Python
Simulates ChaCha20-Poly1305 AEAD encryption and authentication using SHA-256 as a deterministic keystream and tag generator.
from hashlib import sha256
import struct
def chacha20_block(key, counter, nonce):
"""Mock ChaCha20 block: deterministic pseudo-random keystream from key+counter+nonce."""
state_input = key + struct.pack("<I", counter) + nonce + b"ChaCha20"
return sha256(state_input).digest()[:64] # 64-byte keystream bloc…How to Create and Verify HMAC SHA256 API Signatures in Python
Generate and verify HMAC-SHA256 signatures for API requests using Python's hmac, hashlib, and base64 modules.
import hmac
import hashlib
import base64
import json
from datetime import datetime, timezone
def create_api_signature(secret_key: str, method: str, path: str, timestamp: str, body: dict = None) -> str:
"""Create HMAC-SHA256 signature for API request."""
payload = {
"method": method.upper(),
"p…How to Create and Verify an OpenID Connect ID Token in Python
Generate and validate a mock OpenID Connect ID token (JWT) with HS256 signing using only the Python standard library.
import base64
import hashlib
import hmac
import json
import time
from typing import Optional
def b64url_encode(data: bytes) -> str:
return base64.urlsafe_b64encode(data).rstrip(b"=").decode("utf-8")
def b64url_decode(data: str) -> bytes:
padding = "=" * (-len(data) % 4)
return base64.urlsafe_b64decode(…How to Encode and Decode JWT with HS256 in Python
Implement JWT encoding and decoding using HMAC-SHA256 (HS256) with Python's standard library, including signature verification.
import base64
import hashlib
import hmac
import json
def base64url_encode(data: bytes) -> bytes:
return base64.urlsafe_b64encode(data).rstrip(b"=")
def base64url_decode(data: str) -> bytes:
padding = "=" * (-len(data) % 4)
return base64.urlsafe_b64decode(data + padding)
def encode_jwt(payload: dict, …How to Hash Passwords and Authenticate Users in Python
A beginner-friendly dataclass-based design that hashes passwords with PBKDF2 and verifies them securely using constant-time comparisons.
import hashlib
import hmac
import secrets
from dataclasses import dataclass
from typing import Optional
@dataclass
class User:
id: int
username: str
password_hash: str
salt: str
def hash_password(password: str) -> tuple[str, str]:
salt = secrets.token_hex(16)
password_hash = hashlib.pbkdf2_…How to Implement a CSRF Token Double Submit Mock in Python
A mock CSRF protection class that generates and validates double-submit tokens using HMAC-SHA256 with a secret key.
import hmac
import hashlib
import secrets
class CSRFProtection:
def __init__(self, secret_key: str):
self.secret_key = secret_key.encode("utf-8")
def generate_token(self) -> str:
random_value = secrets.token_hex(16)
signature = hmac.new(
self.secret_key, random_value.enco…How to Implement a Vault Dynamic Database Credentials Mock in Python
A Python dataclass-based mock of HashiCorp Vault that issues short-lived database credentials, tracks leases, and revokes them, demonstrating dynamic secrets rotation.
import time
import json
from dataclasses import dataclass, field
from typing import Dict
@dataclass
class DynamicCredential:
username: str
password: str
lease_duration: int
created_at: float = field(default_factory=time.time)
def is_valid(self) -> bool:
return time.time() - self.created_…How to Mock OAuth 2.0 Device Code Flow in Python
A mock implementation of the OAuth 2.0 device authorization grant for testing authentication flows without a real provider.
import hashlib
import time
import uuid
class DeviceCodeFlowMock:
def __init__(self):
self.device_codes = {}
def request_device_code(self, client_id, scope="read write"):
device_code = uuid.uuid4().hex
user_code = str(uuid.uuid4().int)[:8].upper()
expires_in = 300
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