Increase and decrease the namespace metrics counter with events

pkg/metrics/metrics.go

@@ -88,7 +88,7 @@ func InitMetrics() {
 
 	// Register total Namespaces count metric
 	err = registry.Register(promauto.NewGaugeFunc(prometheus.GaugeOpts{
-		Name: "vikunja_namespcae_count",
+		Name: "vikunja_namespace_count",
 		Help: "The total number of namespaces on this instance",
 	}, func() float64 {
 		count, _ := GetCount(NamespaceCountKey)

pkg/models/events.go

@@ -84,6 +84,17 @@ func (n *NamespaceUpdatedEvent) TopicName() string {
 	return "namespace.updated"
 }
 
+// NamespaceDeletedEvent represents a NamespaceDeletedEvent event
+type NamespaceDeletedEvent struct {
+	Namespace *Namespace
+	Doer      *user.User
+}
+
+// TopicName defines the name for NamespaceDeletedEvent
+func (t *NamespaceDeletedEvent) TopicName() string {
+	return "namespace.deleted"
+}
+
 /////////////////
 // List Events //
 /////////////////

pkg/models/listeners.go

@@ -28,6 +28,8 @@ func RegisterListeners() {
 	events.RegisterListener((&TaskCreatedEvent{}).TopicName(), &SendTaskCreatedNotification{})
 	events.RegisterListener((&ListCreatedEvent{}).TopicName(), &IncreaseListCounter{})
 	events.RegisterListener((&ListDeletedEvent{}).TopicName(), &DecreaseListCounter{})
+	events.RegisterListener((&NamespaceCreatedEvent{}).TopicName(), &IncreaseNamespaceCounter{})
+	events.RegisterListener((&NamespaceDeletedEvent{}).TopicName(), &DecreaseNamespaceCounter{})
 }
 
 type SendTaskCreatedNotification struct {
@@ -54,7 +56,7 @@ type IncreaseListCounter struct {
 }
 
 func (s *IncreaseListCounter) Name() string {
-	return "increase.list.counter"
+	return "list.counter.increase"
 }
 
 func (s *IncreaseListCounter) Handle(payload message.Payload) (err error) {
@@ -66,10 +68,43 @@ type DecreaseListCounter struct {
 }
 
 func (s *DecreaseListCounter) Name() string {
-	return "decrease.list.counter"
+	return "list.counter.decrease"
 }
 
 func (s *DecreaseListCounter) Handle(payload message.Payload) (err error) {
 	metrics.UpdateCount(-1, metrics.ListCountKey)
 	return nil
 }
+
+//////
+// Namespace events
+
+// IncreaseNamespaceCounter  represents a listener
+type IncreaseNamespaceCounter struct {
+}
+
+// Name defines the name for the IncreaseNamespaceCounter listener
+func (s *IncreaseNamespaceCounter) Name() string {
+	return "namespace.counter.increase"
+}
+
+// Hanlde is executed when the event IncreaseNamespaceCounter listens on is fired
+func (s *IncreaseNamespaceCounter) Handle(payload message.Payload) (err error) {
+	metrics.UpdateCount(1, metrics.NamespaceCountKey)
+	return nil
+}
+
+// DecreaseNamespaceCounter  represents a listener
+type DecreaseNamespaceCounter struct {
+}
+
+// Name defines the name for the DecreaseNamespaceCounter listener
+func (s *DecreaseNamespaceCounter) Name() string {
+	return "namespace.counter.decrease"
+}
+
+// Hanlde is executed when the event DecreaseNamespaceCounter listens on is fired
+func (s *DecreaseNamespaceCounter) Handle(payload message.Payload) (err error) {
+	metrics.UpdateCount(-1, metrics.NamespaceCountKey)
+	return nil
+}

pkg/models/namespace.go

@@ -24,7 +24,6 @@ import (
 	"time"
 
 	"code.vikunja.io/api/pkg/log"
-	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/api/pkg/user"
 	"code.vikunja.io/web"
 	"xorm.io/builder"
@@ -487,7 +486,6 @@ func (n *Namespace) Create(s *xorm.Session, a web.Auth) (err error) {
 		return err
 	}
 
-	metrics.UpdateCount(1, metrics.NamespaceCountKey)
 	return
 }
 
@@ -552,9 +550,14 @@ func (n *Namespace) Delete(s *xorm.Session, a web.Auth) (err error) {
 		return
 	}
 
-	metrics.UpdateCount(-1, metrics.NamespaceCountKey)
-
-	return
+	doer, err := user.GetFromAuth(a)
+	if err != nil {
+		return err
+	}
+	return events.Publish(&NamespaceDeletedEvent{
+		Namespace: n,
+		Doer:      doer,
+	})
 }
 
 // Update implements the update method via the interface