API design & gRPC
REST best practices, protobuf, API versioning, and backward-compatible service contracts.
How to Decode Basic Auth Credentials in Python
Decode username and password from a Basic Auth header string using base64 and standard string operations.
import base64
def decode_basic_auth(header_value):
"""
Decode credentials from a Basic Auth header value.
Expected format: "Basic base64encoded(username:password)"
Returns a tuple (username, password).
"""
if not header_value.startswith("Basic "):
raise ValueError("Invalid Basic A…
How to Mock an API Key Header Authentication Server in Python
A minimal HTTP server that validates requests using an X-API-Key header and returns JSON responses for authenticated and unauthenticated calls.
import json
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
API_KEYS = {"test-user": "secret-key-123"}
class AuthHandler(BaseHTTPRequestHandler):
def do_GET(self):
auth = self.headers.get("X-API-Key")
if not auth or auth not in API_KEYS.values():
self.send_response…
How to Validate JWT Claims (exp, iss, aud) in Python
This code demonstrates how to decode and validate a JWT's essential claims—expiration (exp), issuer (iss), and audience (aud)—using the PyJWT library, returning clear error messages for common validation failures.
import jwt
from datetime import datetime, timezone, timedelta
SECRET = "mock-secret"
def validate_token(token, expected_iss, expected_aud):
try:
decoded = jwt.decode(
token,
SECRET,
algorithms=["HS256"],
options={"require": ["exp", "iss", "aud"]},
…
How to Validate a JWT Signature in Python with a Mock Secret
Validates a JWT's signature using a mock secret, decoding and handling expired or invalid tokens gracefully.
import jwt
import time
SECRET = "mock_secret_key_123"
def validate_token(token):
try:
payload = jwt.decode(token, SECRET, algorithms=["HS256"])
return f"Valid token. Payload: {payload}"
except jwt.ExpiredSignatureError:
return "Token expired"
except jwt.InvalidTokenError:
…
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