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5 matches
API design & gRPC medium

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.

oauth2 security middleware
Python
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…
13 0 Open
Auth & security at scale easy

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.

pkce oauth2 security
Python
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…
15 0 Open
Auth & security at scale medium

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.

oauth2 device-flow mock
Python
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
        inte…
13 0 Open
Auth & security at scale medium

Mock client credentials machine auth in Python

This code simulates the OAuth2 client-credentials flow for service-to-service calls, generating a mock bearer token with expiry and caching, plus a revoke method, using only the standard library.

oauth2 auth mock
Python
import time
import hashlib
import secrets

class MachineAuth:
    """Mock client-credentials machine auth for service-to-service calls."""
    
    def __init__(self, client_id, client_secret):
        self.client_id = client_id
        self.client_secret = client_secret
        self._token = None
        self._expire…
15 0 Open
Auth & security at scale medium

OAuth2 authorization code flow mock in Python

A minimal HTTP server that mocks the OAuth2 authorization code flow, issuing codes via /authorize and exchanging them for tokens at /token.

oauth2 http-server mock-server
Python
import json
from http.server import BaseHTTPRequestHandler, HTTPServer
from urllib.parse import urlparse, parse_qs

AUTH_CODE_STORE = {}
CLIENT_ID = "demo-client"
REDIRECT_URI = "http://localhost:8000/callback"

class OAuthHandler(BaseHTTPRequestHandler):
    def do_GET(self):
        parsed = urlparse(self.path)
    …
14 0 Open

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