Based on my understanding of complex seating booking flows and the current 5 core tests, here
are additional edge cases we should investigate for a robust low-throughput booking system:

🎯 Critical Edge Cases Not Covered

1. Session Management & User Experience

// E2E-6: Session timeout during booking flow

- User holds seats, session expires mid-booking
- Multiple browser tabs with same user
- User closes browser during payment processing
- Mobile app backgrounding during checkout

2. Payment Integration Edge Cases

// E2E-7: Payment gateway failures

- Stripe webhook delays/failures
- Partial payment confirmations
- Payment succeeds but webhook fails
- Double-charging scenarios (idempotency key failures)
- Currency conversion edge cases

3. Time-Sensitive Scenarios

// E2E-8: Event timing edge cases

- Booking attempts after event start time
- Timezone changes (daylight saving transitions)
- Hold expiration during payment processing
- System clock drift/NTP synchronization issues

4. Data Integrity & Recovery

// E2E-9: Database consistency

- Hold created but seat inventory not decremented
- Order confirmed but hold not released
- Orphaned reservations after system crashes
- Duplicate bookings due to race conditions in different tables

5. Capacity & Overselling Protection

// E2E-10: Inventory management

- Last available seat with multiple simultaneous attempts
- Seat map refresh after holds expire
- Administrative seat blocking/unblocking
- VIP/reserved seat handling

🔍 Specific Test Scenarios to Implement

High Priority (Should implement soon):

1. Hold Extension Scenarios


    - User requests more time during checkout
    - Payment gateway needs extra processing time
    - Network interruption during critical operations

2. Multi-Step Booking Failures


    - Hold → Payment → Confirmation chain breaks at any point
    - Rollback scenarios when confirmation fails
    - Recovery from partial state corruption

3. Admin Override Scenarios


    - Manual seat releases by administrators
    - Emergency event cancellations
    - Bulk seat operations during active bookings

Medium Priority:

4. Cross-Device Booking


    - Start on mobile, complete on desktop
    - Multiple devices attempting same booking
    - Session transfer between devices

5. Network Resilience


    - API timeout handling
    - Partial response scenarios
    - Connection drops during critical operations

6. Event Lifecycle Edge Cases


    - Event postponement during active bookings
    - Venue changes affecting seat maps
    - Capacity reductions after sales begin

🛡️ Defensive Measures to Test

Data Validation

// Test malformed data injection

- Invalid seat IDs in requests
- Negative pricing scenarios
- SQL injection attempts in booking data
- XSS in user input fields

Rate Limiting Edge Cases

// Test burst scenarios

- Rapid-fire booking attempts
- API abuse patterns
- Bot detection scenarios
- Fair queuing under load

Time Window Attacks

// Test timing-based exploits

- Clock manipulation attempts
- Hold time extension exploits
- Payment processing delays to game expiration

📊 Monitoring & Observability Gaps

Missing Metrics to Track:

1. Hold-to-confirmation conversion rates
2. Average time in each booking state
3. Failed payment recovery rates
4. Seat availability accuracy over time
5. User session abandonment patterns

Alert Conditions:

1. Orphaned holds exceeding threshold
2. Payment confirmation delays
3. Seat inventory discrepancies
4. Unusual booking pattern detection

🎪 Venue-Specific Considerations

Seating Constraints:

- Accessibility seat requirements
- Group booking constraints (keeping parties together)
- Restricted view seat handling
- Dynamic pricing based on demand

Business Rules:

- Maximum tickets per customer
- Presale vs general sale transitions
- Member vs public access differences
- Refund and exchange policies

💡 Recommended Next Steps

1. Implement E2E-6 (Session Management) - Most likely to impact real users
2. Add comprehensive payment failure testing - Financial accuracy is critical
3. Create data consistency validation tools - Prevent long-term corruption
4. Build admin intervention scenarios - Support staff need reliable tools
5. Add performance monitoring - Detect issues before they impact users

Would you like me to implement any of these specific test scenarios, or would you prefer to
focus on a particular category of edge cases first?