# Rodauth-OAuth Decision Guide

## TL;DR - Make Your Choice Here

### Option A: Keep Your Rails Implementation
**Best if:** Authorization Code + PKCE is all you need, forever
- Keep your current 450 lines of OIDC controller code
- Maintain incrementally as needs change
- Stay 100% in Rails ecosystem
- Time investment: Ongoing (2-3 months to feature parity)
- Learning curve: None (already know Rails)

### Option B: Switch to Rodauth-OAuth
**Best if:** You need enterprise features, standards compliance, low maintenance
- Replace 450 lines with plugin config
- Get 34 optional features on demand
- OpenID Certified, production-hardened
- Time investment: 4-8 weeks (one-time)
- Learning curve: Medium (learn Roda/Rodauth)

### Option C: Hybrid (Recommended if Option B appeals you)
**Best if:** You want rodauth-oauth benefits without framework change
- Run Rodauth-OAuth as separate microservice
- Keep your Rails app unchanged
- Services talk via HTTP APIs
- Time investment: 2-3 weeks (independent services)
- Learning curve: Low (Roda is isolated)

---

## Decision Matrix

```
┌─────────────────────────────────────────────────────────────────┐
│ Do you need features beyond Authorization Code + PKCE?          │
├─────────────────────────────────────────────────────────────────┤
│                YES ─→ Go to Question 2                          │
│                NO  ─→ KEEP YOUR IMPLEMENTATION                  │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│ Can your team learn Roda (different from Rails)?                │
├─────────────────────────────────────────────────────────────────┤
│                YES ─→ SWITCH TO RODAUTH-OAUTH                   │
│                NO  ─→ Go to Question 3                          │
└─────────────────────────────────────────────────────────────────┘
                              ↓
┌─────────────────────────────────────────────────────────────────┐
│ Can you run separate services (microservices)?                  │
├─────────────────────────────────────────────────────────────────┤
│                YES ─→ USE HYBRID APPROACH                       │
│                NO  ─→ KEEP YOUR IMPLEMENTATION                  │
└─────────────────────────────────────────────────────────────────┘
```

---

## Feature Roadmap Comparison

### Scenario 1: You Need Refresh Tokens (Common)

**Option A (Keep Custom):**
- Implement refresh token endpoints
- Add refresh_token columns to DB
- Token rotation logic
- Estimate: 1-2 weeks of work
- Ongoing: Maintain refresh token security

**Option B (Rodauth-OAuth):**
- Already built and tested
- Just enable: `:oauth_authorization_code_grant` (includes refresh)
- Token rotation: Configurable options
- Estimate: Already included
- Ongoing: Community maintains

**Option C (Hybrid):**
- Rodauth-OAuth handles it
- Your app unchanged
- Same as Option B for this feature

### Scenario 2: You Need Token Revocation

**Option A (Keep Custom):**
- Build `/oauth/revoke` endpoint
- Implement token blacklist or DB update
- Handle race conditions
- Estimate: 1-2 weeks
- Ongoing: Monitor revocation leaks

**Option B (Rodauth-OAuth):**
- Enable `:oauth_token_revocation` feature
- RFC 7009 compliant out of the box
- Estimate: Already included
- Ongoing: Community handles RFC updates

**Option C (Hybrid):**
- Same as Option B

### Scenario 3: You Need Client Credentials Grant

**Option A (Keep Custom):**
- New endpoint logic
- Client authentication (different from user auth)
- Token generation for apps without users
- Estimate: 2-3 weeks
- Ongoing: Test with external clients

**Option B (Rodauth-OAuth):**
- Enable `:oauth_client_credentials_grant` feature
- All edge cases handled
- Estimate: Already included
- Ongoing: Community maintains

**Option C (Hybrid):**
- Same as Option B

---

## Architecture Diagrams

### Current Setup (Your Implementation)
```
┌─────────────────────────────┐
│   Your Rails Application    │
├─────────────────────────────┤
│ app/controllers/            │
│   oidc_controller.rb        │ ← 450 lines of OAuth logic
│                             │
│ app/models/                 │
│   OidcAuthorizationCode    │
│   OidcAccessToken          │
│   OidcUserConsent          │
│                             │
│ app/services/               │
│   OidcJwtService           │
├─────────────────────────────┤
│     Rails ActiveRecord      │
├─────────────────────────────┤
│   PostgreSQL Database       │
│   - oidc_authorization_codes
│   - oidc_access_tokens
│   - oidc_user_consents
│   - applications
└─────────────────────────────┘
```

### Option B: Full Migration
```
┌──────────────────────────────┐
│   Roda + Rodauth-OAuth App   │
├──────────────────────────────┤
│ lib/rodauth_app.rb           │ ← Config (not code!)
│   enable :oidc,              │
│   enable :oauth_pkce,        │
│   enable :oauth_token_...    │
│                              │
│ [Routes auto-mounted]        │
│   /.well-known/config        │
│   /oauth/authorize           │
│   /oauth/token               │
│   /oauth/userinfo            │
│   /oauth/revoke              │
│   /oauth/introspect          │
├──────────────────────────────┤
│    Sequel ORM                │
├──────────────────────────────┤
│   PostgreSQL Database        │
│   - accounts (rodauth)
│   - oauth_applications
│   - oauth_grants (unified!)
│   - optional feature tables
└──────────────────────────────┘
```

### Option C: Microservices Architecture (Hybrid)
```
┌──────────────────────────┐     ┌──────────────────────────┐
│  Your Rails App          │     │  Rodauth-OAuth Service   │
├──────────────────────────┤     ├──────────────────────────┤
│ Normal Rails Controllers │     │ lib/rodauth_app.rb       │
│ & Business Logic         │     │   [OAuth Features]       │
│                          │     │                          │
│ HTTP Calls to →──────────┼─────→ /.well-known/config     │
│ OAuth Service   OAuth    │     │ /oauth/authorize         │
│                 HTTP API │     │ /oauth/token             │
│                          │     │ /oauth/userinfo          │
│ Verify Tokens via →──────┼─────→ /oauth/introspect       │
│ /oauth/introspect        │     │                          │
├──────────────────────────┤     ├──────────────────────────┤
│   Rails ActiveRecord     │     │   Sequel ORM             │
├──────────────────────────┤     ├──────────────────────────┤
│   PostgreSQL             │     │   PostgreSQL             │
│   [business tables]      │     │   [oauth tables]         │
└──────────────────────────┘     └──────────────────────────┘
```

---

## Effort Estimates

### Option A: Keep & Enhance Custom Implementation
```
Refresh Tokens:           1-2 weeks
Token Revocation:         1-2 weeks
Token Introspection:      1-2 weeks
Client Credentials:       2-3 weeks
Device Code:              3-4 weeks
JWT Access Tokens:        1-2 weeks
Session Management:       2-3 weeks
Front-Channel Logout:     1-2 weeks
Back-Channel Logout:      2-3 weeks
─────────────────────────────────
TOTAL FOR PARITY:         15-25 weeks
(4-6 months of work)

ONGOING MAINTENANCE:      ~8-10 hours/month
(security updates, RFC changes, bug fixes)
```

### Option B: Migrate to Rodauth-OAuth
```
Learn Roda/Rodauth:       1-2 weeks
Migrate Database Schema:  1-2 weeks
Replace OIDC Code:        1-2 weeks
Test & Validation:        2-3 weeks
─────────────────────────────────
ONE-TIME EFFORT:          5-9 weeks
(1-2 months)

ONGOING MAINTENANCE:      ~1-2 hours/month
(dependency updates, config tweaks)
```

### Option C: Hybrid Approach
```
Set up Rodauth service:   1-2 weeks
Configure integration:    1-2 weeks
Test both services:       1 week
─────────────────────────────────
ONE-TIME EFFORT:          3-5 weeks
(less than Option B)

ONGOING MAINTENANCE:      ~2-3 hours/month
(maintain two services, but Roda handles OAuth)
```

---

## Real-World Questions to Ask Your Team

### Question 1: Feature Needs
- "Do we need refresh tokens?"
- "Will clients ask for token revocation?"
- "Do we support service-to-service auth (client credentials)?"
- "Will we ever need device code flow (IoT)?"

If YES to any: **Option B or C makes sense**

### Question 2: Maintenance Philosophy
- "Do we want to own the OAuth code?"
- "Can we afford to maintain OAuth compliance?"
- "Do we have experts in OAuth/OIDC?"

If NO to all: **Option B or C is better**

### Question 3: Framework Flexibility
- "Is Rails non-negotiable for this company?"
- "Can our team learn a new framework?"
- "Can we run microservices?"

If Rails is required: **Option C (hybrid)**

### Question 4: Time Constraints
- "Do we have 4-8 weeks for a migration?"
- "Can we maintain OAuth for years?"
- "What if specs change?"

If time-constrained: **Option B is fastest path to full features**

---

## Security Comparison

### Your Implementation
- ✓ PKCE support
- ✓ JWT signing
- ✓ HTTPS recommended
- ✗ Token hashing (stores tokens in plaintext)
- ✗ Token rotation
- ✗ DPoP (token binding)
- ✗ Automatic spec compliance
- Risk: Token theft if DB compromised

### Rodauth-OAuth
- ✓ PKCE support
- ✓ JWT signing
- ✓ Token hashing (bcrypt by default)
- ✓ Token rotation policies
- ✓ DPoP support (RFC 9449)
- ✓ TLS mutual authentication
- ✓ Automatic spec updates
- ✓ Certified compliance
- Risk: Minimal (industry-standard)

---

## Cost-Benefit Summary

### Keep Your Implementation
```
Costs:
  - 15-25 weeks to feature parity
  - Ongoing security monitoring
  - Spec compliance tracking
  - Bug fixes & edge cases
  
Benefits:
  - No framework learning
  - Full code understanding
  - Rails-native patterns
  - Minimal dependencies
```

### Switch to Rodauth-OAuth
```
Costs:
  - 5-9 weeks migration effort
  - Learn Roda/Rodauth
  - Database schema changes
  - Test all flows
  
Benefits:
  - Get 34 features immediately
  - Certified compliance
  - Community-maintained
  - Security best practices
  - Ongoing support
```

### Hybrid Approach
```
Costs:
  - 3-5 weeks setup
  - Learn Roda basics
  - Operate two services
  - Service communication
  
Benefits:
  - All Rodauth-OAuth features
  - Rails app unchanged
  - Independent scaling
  - Clear separation of concerns
```

---

## Decision Scorecard

| Factor | Option A | Option B | Option C |
|--------|----------|----------|----------|
| Initial Time | Low | Medium | Medium-Low |
| Ongoing Effort | High | Low | Medium |
| Feature Completeness | Low | High | High |
| Framework Learning | None | Medium | Low |
| Standards Compliance | Manual | Auto | Auto |
| Deployment Complexity | Simple | Simple | Complex |
| Team Preference | ??? | ??? | ??? |

---

## Next Actions

### For Option A (Keep Custom):
1. Plan feature roadmap (refresh tokens first)
2. Allocate team capacity for implementation
3. Document OAuth decisions
4. Set up security monitoring

### For Option B (Full Migration):
1. Assign someone to learn Roda/Rodauth
2. Run rodauth-oauth examples
3. Plan database migration
4. Schedule migration window
5. Prepare rollback plan

### For Option C (Hybrid):
1. Evaluate microservices capability
2. Run Rodauth-OAuth example
3. Plan service boundaries
4. Set up service communication
5. Plan infrastructure for two services

---

## Still Can't Decide?

Ask these questions:
1. **Will you add features beyond Auth Code + PKCE in next 12 months?**
   - YES → Option B or C
   - NO → Option A

2. **Do you have maintenance bandwidth?**
   - YES → Option A
   - NO → Option B or C

3. **Can you run multiple services?**
   - YES → Option C (best of both)
   - NO → Option B (if framework is OK) or Option A (stay Rails)

---

## Document Files

You now have three documents:
1. **rodauth-oauth-analysis.md** - Deep technical analysis (12 sections)
2. **rodauth-oauth-quick-reference.md** - Quick lookup guide
3. **RODAUTH_DECISION_GUIDE.md** - This decision framework

Read in this order:
1. This guide (make a decision)
2. Quick reference (understand architecture)
3. Analysis (deep dive on your choice)

---

**Made Your Decision?** Create an issue/commit to document your choice and next steps!