Monitoring & Observability

This document details error tracking, distributed performance tracing with Sentry, log noise suppression filters, and the PWA update lifecycle in Scripture Habit.

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1. Sentry Error Tracking & Performance Monitoring

Sentry is integrated across frontend and backend environments to monitor system reliability:

• Performance Tracing (tracesSampleRate: 0.1):
  Samples 10% of HTTP transactions to identify latency bottlenecks in API handlers and rendering cycles.
• Session Replays (replaysOnErrorSampleRate: 1.0):
  Captures user interaction breadcrumbs preceding exceptions to facilitate rapid issue reproduction.
• Normalized Transaction Names:
  Routes with dynamic parameters (e.g., /api/groups/:groupId) group performance metrics under normalized paths.

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2. Noise Suppression (ignoreErrors)

Expected client-side events are filtered to prevent alert fatigue:

• AbortError: Triggered when users navigate away before an in-flight fetch completes.
• permission-denied on Logout: Transient teardown event when active Firestore listeners disconnect during sign-out.

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3. PWA Update Lifecycle

Coordinates seamless Service Worker upgrades without interrupting active user sessions:

PWA Lifecycle Breakdown

1. Background Asset Ingestion
   The browser installs the updated Service Worker in the background, firing a pwa-update-available event to the active client.

2. Non-Intrusive Prompt
   Displays a dismissible notification banner inviting the user to refresh their session.

3. Atomic Cache Activation
   Dispatches skipWaiting() to swap caches and reloads the browser tab to render the latest application build.

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4. Related Documentation

• Architecture Overview
• API Design & Error Handling
• CI/CD & Maintenance Automation