Overview

Objectives

• Add OAuth login without storing user passwords

• Securely handle client secrets and tokens

• Provide a clean user experience with clear logout behavior

• Document configuration for fast onboarding

Prerequisites

• Python and Flask basics

• A GitHub account and access to Developer Settings

• Local run environment

Implementation

1. Registration

• Created a GitHub OAuth app with homepage and callback URLs

• Captured Client ID and Client Secret and stored them securely

2. App integration

• Added an OAuth client to Flask and implemented login, callback, and logout routes

• Scoped requests to basic profile email to minimize permissions

• Stored secrets in environment variables to keep them out of source control

3. Verification

• Ran through the full authorization code flow locally

• Validated token storage in session and confirmed logout clears session data

4. Hardening

• Noted the requirement for HTTPS in production

• Rotated secrets and tested failure modes for missing or invalid credentials

5. Documentation

• Wrote setup steps, environment variable names, and troubleshooting tips

• Included notes on callback URL mismatches and scope errors

Outcomes

• Working OAuth login with GitHub as the provider

• Clean separation of secrets from code

• Clear setup guide that others can follow

Skills demonstrated

• OAuth integration and session handling

• Secure configuration and secret management

• User authentication design