From dfbb3fe6f4f4b21b56a576e0df1d36b149438872 Mon Sep 17 00:00:00 2001
From: kolaente <k@knt.li>
Date: Mon, 1 Feb 2021 21:27:37 +0100
Subject: [PATCH] Increase and decrease the task metrics counter with events

---
 pkg/models/events.go    | 11 +++++++++++
 pkg/models/listeners.go | 41 ++++++++++++++++++++++++++++-------------
 pkg/models/tasks.go     | 15 +++++++++++----
 3 files changed, 50 insertions(+), 17 deletions(-)

diff --git a/pkg/models/events.go b/pkg/models/events.go
index 8c7d06845..1cd8e341c 100644
--- a/pkg/models/events.go
+++ b/pkg/models/events.go
@@ -42,6 +42,17 @@ func (t *TaskUpdatedEvent) TopicName() string {
 	return "task.updated"
 }
 
+// TaskDeletedEvent represents a TaskDeletedEvent event
+type TaskDeletedEvent struct {
+	Task *Task
+	Doer *user.User
+}
+
+// TopicName defines the name for TaskDeletedEvent
+func (t *TaskDeletedEvent) TopicName() string {
+	return "task.deleted"
+}
+
 type TaskAssigneeCreatedEvent struct {
 	Task     *Task
 	Assignee *user.User
diff --git a/pkg/models/listeners.go b/pkg/models/listeners.go
index d39fd3c84..02ffab457 100644
--- a/pkg/models/listeners.go
+++ b/pkg/models/listeners.go
@@ -17,35 +17,50 @@
 package models
 
 import (
-	"code.vikunja.io/api/pkg/metrics"
-	"encoding/json"
-
 	"code.vikunja.io/api/pkg/events"
+	"code.vikunja.io/api/pkg/metrics"
 	"github.com/ThreeDotsLabs/watermill/message"
 )
 
 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{})
+	events.RegisterListener((&TaskCreatedEvent{}).TopicName(), &IncreaseTaskCounter{})
+	events.RegisterListener((&TaskDeletedEvent{}).TopicName(), &DecreaseTaskCounter{})
 }
 
-type SendTaskCreatedNotification struct {
+//////
+// Task Events
+
+// IncreaseTaskCounter  represents a listener
+type IncreaseTaskCounter struct {
 }
 
-func (s *SendTaskCreatedNotification) Name() string {
-	return "task.created.notification"
+// Name defines the name for the IncreaseTaskCounter listener
+func (s *IncreaseTaskCounter) Name() string {
+	return "increase.task.counter"
 }
 
-func (s *SendTaskCreatedNotification) Handle(payload message.Payload) (err error) {
-	event := &TaskCreatedEvent{}
-	err = json.Unmarshal(payload, event)
-	if err != nil {
-		return err
-	}
+// Hanlde is executed when the event IncreaseTaskCounter listens on is fired
+func (s *IncreaseTaskCounter) Handle(payload message.Payload) (err error) {
+	metrics.UpdateCount(1, metrics.TaskCountKey)
+	return nil
+}
 
+// DecreaseTaskCounter  represents a listener
+type DecreaseTaskCounter struct {
+}
+
+// Name defines the name for the DecreaseTaskCounter listener
+func (s *DecreaseTaskCounter) Name() string {
+	return "decrease.task.counter"
+}
+
+// Hanlde is executed when the event DecreaseTaskCounter listens on is fired
+func (s *DecreaseTaskCounter) Handle(payload message.Payload) (err error) {
+	metrics.UpdateCount(-1, metrics.TaskCountKey)
 	return nil
 }
 
diff --git a/pkg/models/tasks.go b/pkg/models/tasks.go
index c5cc94bc7..f56793d3c 100644
--- a/pkg/models/tasks.go
+++ b/pkg/models/tasks.go
@@ -26,7 +26,6 @@ import (
 	"code.vikunja.io/api/pkg/db"
 
 	"code.vikunja.io/api/pkg/config"
-	"code.vikunja.io/api/pkg/metrics"
 	"code.vikunja.io/api/pkg/user"
 	"code.vikunja.io/api/pkg/utils"
 	"code.vikunja.io/web"
@@ -825,8 +824,6 @@ func createTask(s *xorm.Session, t *Task, a web.Auth, updateAssignees bool) (err
 		return err
 	}
 
-	metrics.UpdateCount(1, metrics.TaskCountKey)
-
 	t.setIdentifier(l)
 
 	err = events.Publish(&TaskCreatedEvent{
@@ -1198,7 +1195,17 @@ func (t *Task) Delete(s *xorm.Session, a web.Auth) (err error) {
 		return err
 	}
 
-	metrics.UpdateCount(-1, metrics.TaskCountKey)
+	doer, err := user.GetFromAuth(a)
+	if err != nil {
+		return err
+	}
+	err = events.Publish(&TaskDeletedEvent{
+		Task: t,
+		Doer: doer,
+	})
+	if err != nil {
+		return
+	}
 
 	err = updateListLastUpdated(s, &List{ID: t.ListID})
 	return