Idempotency & Retry Simulation

Supervisors on remote construction sites often suffer from unstable network dropouts. This tool simulates the mobile supervisor app storing check-ins locally when offline, then batch syncing them when a signal returns.

🔄 Testing Idempotency: Submit a punch multiple times in succession. The API Gateway absorbs duplicate requests matching the UUID token key, returning a 202 Accepted instantly while dispatching the background job exactly once.

📶 Offline Fallback Queue: Toggle the signal switch on the simulated phone to OFFLINE. Punches are buffered in local state. Reconnect to sync, demonstrating chronological out-of-order logs.

Seeded Verification Data

@foreach($workers as $w) @endforeach

Worker	Role	PIN	NFC UID Tag
{{ $w->name }}	{{ str_replace('_', ' ', $w->role) }}	@if($w->name == 'John Doe') 1234 @elseif($w->name == 'Jane Smith') 5678 @elseif($w->name == 'Bob Johnson') 9012 @else 1111 @endif	{{ $w->nfc_uid }}

* Note: PIN check is validated securely on the server using hashed comparisons.

12:00

Online

Supervisor App

BuildTracker

Network

NFC Attendance Punch

Select Worker

Select Site

Action

Worker PIN

BLE Presence Beacon

Target Site

Terminal logs

Simulator ready...

Dashboard