ReadMeABook/documentation/backend/services/notifications.md

Notification System

Status: ✅ Implemented | Extensible notification system with Discord, ntfy, and Pushover support

Overview

Sends notifications for audiobook request events (pending approval, approved, available, error) to configured backends. Non-blocking, atomic per-backend failure handling. Proper notification timing for all request flows including interactive search.

Key Details

• Backends: Apprise (API), Discord (webhooks), ntfy (API), Pushover (API)
• Events: request_pending_approval, request_approved, request_available, request_error
• Encryption: AES-256-GCM for sensitive config (webhook URLs, API keys, notification URLs)
• Delivery: Async via Bull job queue (priority 5)
• Failure Handling: Non-blocking, Promise.allSettled (one backend fails, others succeed)

Database Schema

model NotificationBackend {
  id        String   @id @default(uuid())
  type      String   // 'apprise' | 'discord' | 'ntfy' | 'pushover'
  name      String   // User-friendly label
  config    Json     // Encrypted sensitive values
  events    Json     // Array of subscribed events
  enabled   Boolean  @default(true)
  createdAt DateTime @default(now())
  updatedAt DateTime @updatedAt
}

Event Types

Event	Trigger	Notification Sent When
request_pending_approval	User creates request	Request needs admin approval
request_approved	Admin approves OR auto-approval	Request approved (manual or auto)
request_available	Plex/ABS scan completes	Audiobook available in library
request_error	Download/import fails	Request failed at any stage

Notification Triggers

Request Creation (POST /api/requests)

• Automatic search, approval needed: status === 'awaiting_approval' → request_pending_approval
• Automatic search, auto-approved: status === 'pending' → request_approved
• Interactive search: NO notification yet (deferred until torrent selection)

BookDate Swipe (POST /api/bookdate/swipe)

• Right swipe, approval needed: status === 'awaiting_approval' → request_pending_approval
• Right swipe, auto-approved: status === 'pending' → request_approved

Request with Pre-Selected Torrent (POST /api/audiobooks/request-with-torrent)

• Approval needed: status === 'awaiting_approval' → request_pending_approval
• Auto-approved: status === 'downloading' → request_approved

Torrent Selection for Existing Request (POST /api/requests/[id]/select-torrent)

• Approval needed: status === 'awaiting_approval' → request_pending_approval
• Auto-approved: status === 'downloading' → request_approved

Admin Approval (POST /api/admin/requests/[id]/approve)

• Approve (with or without pre-selected torrent): After job triggered → request_approved
• Deny: No notification

Request Available (processors: scan-plex, plex-recently-added)

• After status: 'available' update → request_available
• Includes user info in query (plexUsername)

Request Error (processors: monitor-download, organize-files)

• After status: 'failed' or status: 'warn' update → request_error
• Includes error message in payload

Configuration Encryption

Encrypted Values:

• Apprise: urls, authToken
• Discord: webhookUrl
• ntfy: accessToken
• Pushover: userKey, appToken

Pattern: iv:authTag:encryptedData (base64)

Masking: Sensitive values returned as •••••••• in API responses

Preservation: Masked values preserved on update (if value === '••••••••', use existing encrypted value)

Message Formatting

Apprise (JSON via Apprise API):

• Type: info (pending), success (approved/available), failure (error)
• Modes: Stateless (send URLs directly) or Stateful (use persistent configKey, optional tag filter)
• Endpoint: {serverUrl}/notify/ (stateless) or {serverUrl}/notify/{configKey} (stateful)
• Auth: Optional Bearer token via authToken config field
• Format: Event title + book details + user + error (if applicable)

Discord (Rich Embeds):

• Color-coded by event (yellow=pending, green=approved, blue=available, red=error)
• Fields: Title, Author, Requested By, Error (if applicable)
• Footer: Request ID
• Timestamp: Event time

ntfy (JSON with Tags):

• Tags: mailbox_with_mail, white_check_mark, tada, x (rendered as emojis by ntfy)
• Priority: Default (3) for pending/approved, High (4) for available/error
• Format: Event title + book details + user + error (if applicable)
• Auth: Optional Bearer token via accessToken config field
• Server: Configurable serverUrl (default: https://ntfy.sh)

Pushover (Plain Text with Emojis):

• Emojis: 📬 📬 🎉 ❌
• Priority: Normal (0) for pending/approved, High (1) for available/error
• Format: Event title + book details + user + error (if applicable)

API Endpoints

GET /api/admin/notifications

• Returns all backends (sensitive values masked)

POST /api/admin/notifications

• Create backend (encrypts sensitive values)
• Body: {type, name, config, events, enabled}

GET /api/admin/notifications/[id]

• Get single backend (sensitive values masked)

PUT /api/admin/notifications/[id]

• Update backend (preserves masked values, encrypts new values)

DELETE /api/admin/notifications/[id]

• Delete backend

POST /api/admin/notifications/test

• Test notification (synchronous, not via job queue)
• Body: {type, config} (plaintext for testing)
• Sends test payload: "The Hitchhiker's Guide to the Galaxy" by Douglas Adams

UI Components

NotificationsTab (src/app/admin/settings/tabs/NotificationsTab)

• Type selector cards (Discord: indigo "D", Pushover: blue "P")
• Configured backends grid (3 columns)
• Backend cards: type icon, name, enabled status, event count, edit/delete actions
• Modal: type-specific forms, event checkboxes, enable toggle, test button

Modal Features:

• Type-first selection (user clicks "Add Discord" or "Add Pushover")
• Password inputs for sensitive values
• Event subscription checkboxes (4 events, default: available + error)
• Test button (sends synchronous test notification)
• Save button (validates and creates/updates backend)

Job Queue Integration

Job Type: send_notification (priority 5, concurrency 5)

Payload:

{
  jobId?: string,
  event: string,
  requestId: string,
  title: string,
  author: string,
  userName: string,
  message?: string,
  timestamp: Date
}

Processor: src/lib/processors/send-notification.processor.ts

• Calls NotificationService.sendNotification()
• Non-blocking error handling (logs but doesn't throw)

Queue Method: addNotificationJob(event, requestId, title, author, userName, message?)

Architecture

Provider Pattern: INotificationProvider interface + registry (matches IAuthProvider pattern)

src/lib/services/notification/
  INotificationProvider.ts          # Interface + shared types
  notification.service.ts           # Core service with registry
  index.ts                          # Re-exports
  providers/
    apprise.provider.ts             # Apprise API (100+ services)
    discord.provider.ts             # Discord webhook
    ntfy.provider.ts                # ntfy API
    pushover.provider.ts            # Pushover API

Registry: Module-level Map<string, INotificationProvider> with registerProvider() / getProvider()

INotificationProvider interface:

• type: string — provider identifier (registry key)
• sensitiveFields: string[] — fields needing encryption/masking
• metadata: ProviderMetadata — self-describing UI/validation metadata
• send(config, payload): Promise<void> — receives decrypted config

ProviderMetadata: { type, displayName, description, iconLabel, iconColor, configFields[] } ProviderConfigField: { name, label, type, required, placeholder?, defaultValue?, options? }

Helper functions:

• getRegisteredProviderTypes(): string[] — all registered type keys
• getAllProviderMetadata(): ProviderMetadata[] — metadata for all providers

API Endpoint: GET /api/admin/notifications/providers — returns all provider metadata (admin-only)

Extensibility

Adding New Backend (2 steps):

1. Create providers/email.provider.ts implementing INotificationProvider:
   • Set type = 'email', sensitiveFields = ['smtpPassword']
   • Set metadata with displayName, description, iconLabel, iconColor, configFields
   • Implement send() with email-specific logic
2. Register in notification.service.ts: registerProvider(new EmailProvider()) + re-export from index.ts

No UI changes, no API route changes, no Zod schema changes needed — the UI renders dynamically from provider metadata.

Adding New Event (e.g., download_complete):

1. Add 'download_complete' to NotificationEvent enum
2. Add to event labels in UI
3. Add trigger point in processor
4. Add message formatting in Discord/Pushover formatters

Tech Stack

• Bull (job queue)
• Node.js crypto (AES-256-GCM encryption)
• Apprise API, Discord webhooks, ntfy API, Pushover API
• React (UI), Tailwind CSS (styling)

Related

• Job Queue System
• Config Encryption
• Settings Pages