Extracting email functions into a service (#14802)

* Extracting email functions into a service

* Fixing two shadowing errors

* Address PR review comments

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/email_batching_test.go

@@ -23,7 +23,7 @@ func TestHandleNewNotifications(t *testing.T) {
 	id3 := model.NewId()
 
 	// test queueing of received posts by user
-	job := NewEmailBatchingJob(th.Server, 128)
+	job := NewEmailBatchingJob(th.Server.EmailService, 128)
 
 	job.handleNewNotifications()
 
@@ -58,7 +58,7 @@ func TestHandleNewNotifications(t *testing.T) {
 	require.Len(t, job.pendingNotifications[id3], 1, "should have received 1 post for user3")
 
 	// test ordering of received posts
-	job = NewEmailBatchingJob(th.Server, 128)
+	job = NewEmailBatchingJob(th.Server.EmailService, 128)
 
 	job.Add(&model.User{Id: id1}, &model.Post{UserId: id1, Message: "test1"}, &model.Team{Name: "team"})
 	job.Add(&model.User{Id: id1}, &model.Post{UserId: id1, Message: "test2"}, &model.Team{Name: "team"})
@@ -77,7 +77,7 @@ func TestCheckPendingNotifications(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
-	job := NewEmailBatchingJob(th.Server, 128)
+	job := NewEmailBatchingJob(th.Server.EmailService, 128)
 	job.pendingNotifications[th.BasicUser.Id] = []*batchedNotification{
 		{
 			post: &model.Post{
@@ -205,7 +205,7 @@ func TestCheckPendingNotificationsDefaultInterval(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
-	job := NewEmailBatchingJob(th.Server, 128)
+	job := NewEmailBatchingJob(th.Server.EmailService, 128)
 
 	// bypasses recent user activity check
 	channelMember, err := th.App.Srv().Store.Channel().GetMember(th.BasicChannel.Id, th.BasicUser.Id)
@@ -243,7 +243,7 @@ func TestCheckPendingNotificationsCantParseInterval(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
-	job := NewEmailBatchingJob(th.Server, 128)
+	job := NewEmailBatchingJob(th.Server.EmailService, 128)
 
 	// bypasses recent user activity check
 	channelMember, err := th.App.Srv().Store.Channel().GetMember(th.BasicChannel.Id, th.BasicUser.Id)
@@ -304,7 +304,7 @@ func TestRenderBatchedPostGeneric(t *testing.T) {
 		return translationID
 	}
 
-	var rendered = th.Server.renderBatchedPost(notification, channel, sender, "http://localhost:8065", "", translateFunc, "en", model.EMAIL_NOTIFICATION_CONTENTS_GENERIC)
+	var rendered = th.Server.EmailService.renderBatchedPost(notification, channel, sender, "http://localhost:8065", "", translateFunc, "en", model.EMAIL_NOTIFICATION_CONTENTS_GENERIC)
 	require.NotContains(t, rendered, post.Message, "Rendered email should not contain post contents when email notification contents type is set to Generic.")
 }
 
@@ -329,6 +329,6 @@ func TestRenderBatchedPostFull(t *testing.T) {
 		return translationID
 	}
 
-	var rendered = th.Server.renderBatchedPost(notification, channel, sender, "http://localhost:8065", "", translateFunc, "en", model.EMAIL_NOTIFICATION_CONTENTS_FULL)
+	var rendered = th.Server.EmailService.renderBatchedPost(notification, channel, sender, "http://localhost:8065", "", translateFunc, "en", model.EMAIL_NOTIFICATION_CONTENTS_FULL)
 	require.Contains(t, rendered, post.Message, "Rendered email should contain post contents when email notification contents type is set to Full.")
 }