authentication

Authentication Skill

Bonded to: api-development-agent (Secondary)

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Quick Start

# Invoke authentication skill
"Implement JWT authentication for my API"
"Set up OAuth2 with Google login"
"Configure role-based access control"

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Auth Methods Comparison

Method	Best For	Stateless	Complexity
JWT	APIs, microservices	Yes	Medium
OAuth2	Third-party login	Yes	High
Session	Traditional web apps	No	Low
API Key	Simple integrations	Yes	Low

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Examples

JWT Authentication

from jose import jwt
from datetime import datetime, timedelta

SECRET_KEY = "your-secret-key"
ALGORITHM = "HS256"

def create_access_token(user_id: str, expires_delta: timedelta = timedelta(minutes=30)):
    expire = datetime.utcnow() + expires_delta
    return jwt.encode(
        {"sub": user_id, "exp": expire},
        SECRET_KEY,
        algorithm=ALGORITHM
    )

def verify_token(token: str) -> str:
    payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
    return payload.get("sub")

RBAC Implementation

from enum import Enum
from functools import wraps

class Role(Enum):
    ADMIN = "admin"
    USER = "user"
    VIEWER = "viewer"

PERMISSIONS = {
    Role.ADMIN: ["read", "write", "delete", "admin"],
    Role.USER: ["read", "write"],
    Role.VIEWER: ["read"]
}

def require_permission(permission: str):
    def decorator(func):
        @wraps(func)
        async def wrapper(user, *args, **kwargs):
            if permission not in PERMISSIONS.get(user.role, []):
                raise HTTPException(status_code=403)
            return await func(user, *args, **kwargs)
        return wrapper
    return decorator

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Security Checklist

• Use HTTPS everywhere
• Short-lived access tokens (15-60 min)
• Refresh token rotation
• Secure token storage (HttpOnly cookies)
• Rate limiting on auth endpoints
• Account lockout after failed attempts

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Troubleshooting

Issue	Cause	Solution
Token expired	Short TTL	Implement refresh tokens
Invalid signature	Wrong secret	Verify SECRET_KEY
401 on valid token	Clock skew	Sync server time

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Resources

• JWT.io Debugger
• OAuth 2.0 Simplified