MM-40813: Use config service more extensively (#19679)

https://mattermost.atlassian.net/browse/MM-40816

```release-note
NONE
```

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

api4/user_test.go

@@ -3542,7 +3542,7 @@ func TestLoginWithLag(t *testing.T) {
 			t.Skipf("requires test flag: -mysql-replica")
 		}
 
-		if *th.App.Srv().Config().SqlSettings.DriverName != model.DatabaseDriverMysql {
+		if *th.App.Config().SqlSettings.DriverName != model.DatabaseDriverMysql {
 			t.Skipf("requires %q database driver", model.DatabaseDriverMysql)
 		}
 

app/channels.go

@@ -247,9 +247,9 @@ func (ch *Channels) Stop() error {
 }
 
 func (ch *Channels) AddConfigListener(listener func(*model.Config, *model.Config)) string {
-	return ch.srv.AddConfigListener(listener)
+	return ch.cfgSvc.AddConfigListener(listener)
 }
 
 func (ch *Channels) RemoveConfigListener(id string) {
-	ch.srv.RemoveConfigListener(id)
+	ch.cfgSvc.RemoveConfigListener(id)
 }

app/post_test.go

@@ -2379,7 +2379,7 @@ func TestReplyToPostWithLag(t *testing.T) {
 	th := Setup(t).InitBasic()
 	defer th.TearDown()
 
-	if *th.App.Srv().Config().SqlSettings.DriverName != model.DatabaseDriverMysql {
+	if *th.App.Config().SqlSettings.DriverName != model.DatabaseDriverMysql {
 		t.Skipf("requires %q database driver", model.DatabaseDriverMysql)
 	}
 

app/product_notices.go

@@ -235,12 +235,12 @@ func (a *App) GetProductNotices(c *request.Context, userID, teamID string, clien
 	isTeamAdmin := a.SessionHasPermissionToTeam(*c.Session(), teamID, model.PermissionManageTeam)
 
 	// check if notices for regular users are disabled
-	if !*a.Srv().Config().AnnouncementSettings.UserNoticesEnabled && !isSystemAdmin {
+	if !*a.Config().AnnouncementSettings.UserNoticesEnabled && !isSystemAdmin {
 		return []model.NoticeMessage{}, nil
 	}
 
 	// check if notices for admins are disabled
-	if !*a.Srv().Config().AnnouncementSettings.AdminNoticesEnabled && (isTeamAdmin || isSystemAdmin) {
+	if !*a.Config().AnnouncementSettings.AdminNoticesEnabled && (isTeamAdmin || isSystemAdmin) {
 		return []model.NoticeMessage{}, nil
 	}
 
@@ -251,7 +251,7 @@ func (a *App) GetProductNotices(c *request.Context, userID, teamID string, clien
 
 	sku := a.Srv().ClientLicense()["SkuShortName"]
 	isCloud := a.Srv().License() != nil && *a.Srv().License().Features.Cloud
-	dbName := *a.Srv().Config().SqlSettings.DriverName
+	dbName := *a.Config().SqlSettings.DriverName
 
 	var searchEngineName, searchEngineVersion string
 	if engine := a.Srv().SearchEngine; engine != nil && engine.ElasticsearchEngine != nil {
@@ -339,8 +339,8 @@ func (a *App) UpdateViewedProductNoticesForNewUser(userID string) {
 
 // UpdateProductNotices is called periodically from a scheduled worker to fetch new notices and update the cache
 func (a *App) UpdateProductNotices() *model.AppError {
-	url := *a.Srv().Config().AnnouncementSettings.NoticesURL
-	skip := *a.Srv().Config().AnnouncementSettings.NoticesSkipCache
+	url := *a.Config().AnnouncementSettings.NoticesURL
+	skip := *a.Config().AnnouncementSettings.NoticesSkipCache
 	mlog.Debug("Will fetch notices from", mlog.String("url", url), mlog.Bool("skip_cache", skip))
 	var err error
 	a.ch.cachedPostCount, err = a.Srv().Store.Post().AnalyticsPostCount("", false, false)

app/server.go

@@ -2086,9 +2086,9 @@ func (a *App) getNotificationsLog() (*model.FileData, string) {
 	var warning string
 
 	// Getting notifications.log
-	if *a.Srv().Config().NotificationLogSettings.EnableFile {
+	if *a.Config().NotificationLogSettings.EnableFile {
 		// notifications.log
-		notificationsLog := config.GetNotificationsLogFileLocation(*a.Srv().Config().LogSettings.FileLocation)
+		notificationsLog := config.GetNotificationsLogFileLocation(*a.Config().LogSettings.FileLocation)
 
 		notificationsLogFileData, notificationsLogFileDataErr := ioutil.ReadFile(notificationsLog)
 
@@ -2113,9 +2113,9 @@ func (a *App) getMattermostLog() (*model.FileData, string) {
 	var warning string
 
 	// Getting mattermost.log
-	if *a.Srv().Config().LogSettings.EnableFile {
+	if *a.Config().LogSettings.EnableFile {
 		// mattermost.log
-		mattermostLog := config.GetLogFileLocation(*a.Srv().Config().LogSettings.FileLocation)
+		mattermostLog := config.GetLogFileLocation(*a.Config().LogSettings.FileLocation)
 
 		mattermostLogFileData, mattermostLogFileDataErr := ioutil.ReadFile(mattermostLog)
 

app/session.go

@@ -255,7 +255,7 @@ func (a *App) UpdateLastActivityAtIfNeeded(session model.Session) {
 // A new ExpiresAt is only written if enough time has elapsed since last update.
 // Returns true only if the session was extended.
 func (a *App) ExtendSessionExpiryIfNeeded(session *model.Session) bool {
-	if !*a.Srv().Config().ServiceSettings.ExtendSessionLengthWithActivity {
+	if !*a.Config().ServiceSettings.ExtendSessionLengthWithActivity {
 		return false
 	}