E5-F5: Queue Connection Resilience

Epic: E5: Waiting Queue System

Size: S (Small)

Problem / Outcome

Users don't lose position if connection drops briefly.

Scope

In-Scope:

• Position persists for 30 minutes after disconnect
• Reconnect restores original position
• Grace period expiration handling

Out-of-Scope:

• Indefinite persistence

Acceptance Criteria

• AC1: Given connection lost, position persists for 30 minutes
• AC2: On reconnect within 30 minutes, original position restored
• AC3: On reconnect after 30 minutes, position lost, user must rejoin

Data Model Impact

QueueEntry table:
- last_heartbeat (TIMESTAMP)
- grace_period_expires_at (TIMESTAMP, nullable)
- is_connected (BOOLEAN)

Heartbeat mechanism:
- Client sends heartbeat every 30 seconds
- Server marks disconnected after 60 seconds of no heartbeat
- Grace period starts on disconnect detection

Permissions/Roles

• System

How to Verify

npm test -- --grep "queue resilience"

Expected: Position retained within grace period.

Dependencies

• E5-F1: Queue Join and Position Assignment

Implementation Tasks

See E5: Waiting Queue Tasks

Doc References

• Waiting Queue Flow

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Last Updated: January 2026