• ✅ bcrypt password hashing: All passwords are hashed using bcrypt with automatic salt generation
• ✅ No plaintext storage: Passwords are never stored in plaintext; only hashes are persisted
• ✅ Password validation: Minimum 8 characters, maximum 128 characters enforced via Pydantic schemas
• ✅ No password logging: Passwords are never logged or exposed in error messages

• ✅ Environment-based secrets: JWT_SECRET_KEY loaded from environment variables
• ✅ Token expiration: JWT tokens expire after configurable time (default: 30 minutes)
• ✅ Secret validation: Startup validation warns if default secret is used in production
• ✅ Algorithm enforcement: JWT algorithm (HS256) is explicitly enforced during validation

• ✅ Pydantic schemas: All request payloads validated via Pydantic models
• ✅ Type safety: Strong typing prevents malformed input
• ✅ HTTP status codes: Proper error codes (400, 401, 422) for validation failures
• ✅ Username validation: Alphanumeric + underscores, 3-50 characters
• ✅ Password validation: 8-128 characters enforced

• ✅ Explicit origins: CORS configured with explicit allowed origins (no wildcard)
• ✅ Environment-driven: CORS_ORIGINS configurable via environment variable
• ✅ Wildcard rejection: Wildcard (*) is explicitly rejected for security
• ✅ Production-ready: Default allows localhost for development; production must set specific origins

• ⚠️ Not implemented: No rate limiting middleware is currently installed
• 📝 Recommendation: For production, implement rate limiting using:
  • FastAPI middleware (e.g., slowapi)
  • Reverse proxy (nginx, Cloudflare)
  • API Gateway (AWS API Gateway, Kong)
• 📝 Priority endpoints: /auth/login, /auth/register, /chat should be rate-limited

• ✅ No secret logging: Secrets (JWT keys, passwords, tokens) are never logged
• ✅ Graceful failure: Missing secrets (e.g., TELEGRAM_BOT_TOKEN) fail gracefully without crashing
• ✅ Environment validation: Security configuration validated on startup with warnings
• ✅ Debug mode: Sensitive endpoints (docs) disabled in production (DEBUG=false)

# JWT Configuration (REQUIRED in production)
JWT_SECRET_KEY=<strong-random-secret-min-32-chars>

# CORS Configuration (REQUIRED in production)
CORS_ORIGINS=https://yourdomain.com,https://www.yourdomain.com

# Optional (has defaults for development)
JWT_ALGORITHM=HS256
JWT_ACCESS_TOKEN_EXPIRE_MINUTES=30
DEBUG=false

The application will issue warnings (not errors) for:

• Default JWT_SECRET_KEY in production
• CORS wildcard usage
• Short JWT secrets (< 32 chars) in production

These warnings allow development and tests to run while alerting to security issues.

All security measures are tested without requiring:

• Real secrets or API keys
• Network access
• External services

Tests validate:

• Password hashing and verification
• JWT token creation and validation
• Input validation and error handling
• CORS configuration