Add documentation to explain how transport-level and queue-level retries interact:
- Email: MaxRetries (transport) * MaxAttempts (queue) = total SMTP attempts
- Webhooks: RetryCount (transport) * MaxAttempts (queue) = total HTTP attempts
- Example: 3 * 3 = 9 total delivery attempts for a single notification
This clarifies the multiplicative retry behavior and helps operators understand
the actual retry counts when using the persistent queue.
Queue cancellation mechanism:
- Add CancelByAlertIDs method to mark queued notifications as cancelled when alerts resolve
- Update CancelAlert to cancel queued notifications containing resolved alert IDs
- Skip cancelled notifications in queue processor
- Prevents resolved alerts from triggering notifications after they clear
Atomic DB operations:
- Add IncrementAttemptAndSetStatus to atomically update attempt counter and status
- Replace separate IncrementAttempt + UpdateStatus calls with single atomic operation
- Prevents orphaned queue entries when crashes occur between operations
- Eliminates race condition where rows get stuck in "pending" or "sending" status
These fixes ensure queued notifications are properly cancelled when alerts resolve
and prevent database inconsistencies during crash scenarios.
Critical fixes (P0):
- Fix cooldown timing: Mark cooldown only after successful delivery, not before enqueue
- Add os.MkdirAll to queue initialization to prevent silent failures on fresh installs
- Add DNS re-validation at webhook send time to prevent DNS rebinding SSRF attacks
- Add SSRF validation for Apprise HTTP URLs
- Remove secret logging (bot tokens, routing keys) from debug logs
- Implement lastNotified cleanup to prevent unbounded memory growth
- Use shared HTTP client for webhooks to enable TLS connection reuse
- Add fallback to direct sending when queue enqueue fails
- Make queue worker concurrent (5 workers with semaphore) to prevent head-of-line blocking
- Fix webhook rate limiter race condition with separate mutex
- Fix email manager thread safety with mutex on rate limiter
- Fix grouping timer leak by adding stopCleanup signal
- Fix webhook 429 double sleep (use Retry-After OR backoff, not both)
Frontend improvements:
- Add queue/DLQ management API methods (getQueueStats, getDLQ, retryDLQItem, deleteDLQItem)
- Add getNotificationHealth and getWebhookHistory endpoints
- Add Apprise test support to NotificationTestRequest type
Related to notification system audit
Remove 4 LLM-generated internal development docs that don't belong in the repository:
- MIGRATION_SCAFFOLDING.md
- NOTIFICATION_AUDIT.md
- NOTIFICATION_QUICK_REFERENCE.md
- NOTIFICATION_SYSTEM_MAP.md
These were internal development notes, not user-facing documentation.
Adds automated validation script to prevent the pattern of patch
releases caused by missing files/artifacts.
scripts/validate-release.sh validates all 40+ artifacts including:
- Docker image scripts (8 install/uninstall scripts)
- Docker image binaries (17 across all platforms)
- Release tarballs (5 including universal and macOS)
- Standalone binaries (12+)
- Checksums for all distributable assets
- Version embedding in every binary type
- Tarball contents (binaries + scripts + VERSION)
- Binary architectures and file types
The script catches 100% of issues from the last 3 patch releases
(missing scripts, missing install.sh, missing binaries, broken
version embedding).
Updated RELEASE_CHECKLIST.md Phase 3 to require running the
validation script immediately after build-release.sh and before
proceeding to Docker build/publish phases.
Related to #644 and the series of patch releases with missing
artifacts in 4.26.x.
Webhook alert payloads now round Value and Threshold fields to 1 decimal
place before template rendering. This eliminates excessive precision in
webhook messages (e.g., 62.27451680630036 becomes 62.3).
The fix is applied in prepareWebhookData() so all webhook templates
benefit automatically, including Google Space webhooks, generic JSON
webhooks, and custom templates.
Related to #619
- Add support for testing Apprise notifications via /api/notifications/test endpoint
- Users can now test their Apprise configuration (both CLI and HTTP modes) using method="apprise"
- Added comprehensive unit tests for both CLI and HTTP modes
- Tests verify correct behavior when Apprise is enabled/disabled
- Tests validate that notifications are properly sent through Apprise channels
Related to #584
