Notifications

SLOzy delivers multi-channel alert notifications through internal/notifications/.

Architecture

SLO Burn Rate → Notification Service → Queue → Workers → Channel Delivery

The Service (internal/notifications/service.go) manages delivery with background workers, deduplication, and retry logic.

Channels

Channel	Delivery Implementation	Configuration Required
Email	SMTP or HTTP API (deliverViaAPI)	to, from, provider endpoint
Slack	Slack webhook with rich attachments	webhook_url
Webhook	Generic HTTP POST	webhook_url, optional headers

Each channel implements the ChannelDelivery interface:

type ChannelDelivery interface {
    Deliver(ctx context.Context, notification *Notification, config map[string]string) error
    Validate(config map[string]string) error
    GetName() string
}

Alert Rules & Priority Levels

Notifications carry a priority level defined in NotificationPriority:

const (
    NotificationPriorityLow      = "low"
    NotificationPriorityMedium   = "medium"
    NotificationPriorityHigh     = "high"
    NotificationPriorityCritical = "critical"
)

Alert types: violation, warning, recovery, manual.

Slack messages use color-coded attachments based on priority (red for critical, orange for high, yellow for medium, green for low).

Retry Logic

The service uses exponential backoff:

func (s *Service) calculateRetryDelay(attempt int) time.Duration {
    delay := float64(baseDelay) * (backoffMultiplier ^ attempt)
    return min(delay, 5 * time.Minute)
}

• Configurable MaxRetries, RetryDelay, and RetryBackoffMultiplier
• Delivery capped at 5 minutes max per attempt

Deduplication

When enabled, the service checks for duplicate notifications within a configurable window using a cache key:

notif:{slo_id}:{channel_id}:{alert_type}:{priority}

Configuration

type NotificationConfig struct {
    MaxRetries            int
    RetryDelay            time.Duration
    RetryBackoffMultiplier float64
    AsyncQueueSize        int
    EnableAsyncDelivery   bool
    DeliveryTimeout       time.Duration
    EnableDeduplication   bool
    DeduplicationWindow   time.Duration
}