MM-10658 Change config fields to pointers (#9033)

* MM 10658 Change config fields to pointers (#8898)

* Change fields of config structs to pointers and set defaults

MM-10658 https://github.com/mattermost/mattermost-server/issues/8841

* Fix tests that go broken during switching config structs to pointers

MM-10658 https://github.com/mattermost/mattermost-server/issues/8841

* Apply changes of current master while switching config structs to pointers

MM-10658 https://github.com/mattermost/mattermost-server/issues/8841

* Fix new config pointer uses

* Fix app tests

* Fix mail test

* remove debugging statement

* fix TestUpdateConfig

* assign config consistently

* initialize AmazonS3Region in TestS3TestConnection

* initialize fields for TestEmailTest

* fix TestCheckMandatoryS3Fields

app/admin.go

@@ -51,8 +51,8 @@ func (a *App) GetLogs(page, perPage int) ([]string, *model.AppError) {
 func (a *App) GetLogsSkipSend(page, perPage int) ([]string, *model.AppError) {
 	var lines []string
 
-	if a.Config().LogSettings.EnableFile {
-		file, err := os.Open(utils.GetLogFileLocation(a.Config().LogSettings.FileLocation))
+	if *a.Config().LogSettings.EnableFile {
+		file, err := os.Open(utils.GetLogFileLocation(*a.Config().LogSettings.FileLocation))
 		if err != nil {
 			return nil, model.NewAppError("getLogs", "api.admin.file_read_error", nil, err.Error(), http.StatusInternalServerError)
 		}
@@ -221,17 +221,17 @@ func (a *App) RecycleDatabaseConnection() {
 }
 
 func (a *App) TestEmail(userId string, cfg *model.Config) *model.AppError {
-	if len(cfg.EmailSettings.SMTPServer) == 0 {
+	if len(*cfg.EmailSettings.SMTPServer) == 0 {
 		return model.NewAppError("testEmail", "api.admin.test_email.missing_server", nil, utils.T("api.context.invalid_param.app_error", map[string]interface{}{"Name": "SMTPServer"}), http.StatusBadRequest)
 	}
 
 	// if the user hasn't changed their email settings, fill in the actual SMTP password so that
 	// the user can verify an existing SMTP connection
-	if cfg.EmailSettings.SMTPPassword == model.FAKE_SETTING {
-		if cfg.EmailSettings.SMTPServer == a.Config().EmailSettings.SMTPServer &&
-			cfg.EmailSettings.SMTPPort == a.Config().EmailSettings.SMTPPort &&
-			cfg.EmailSettings.SMTPUsername == a.Config().EmailSettings.SMTPUsername {
-			cfg.EmailSettings.SMTPPassword = a.Config().EmailSettings.SMTPPassword
+	if *cfg.EmailSettings.SMTPPassword == model.FAKE_SETTING {
+		if *cfg.EmailSettings.SMTPServer == *a.Config().EmailSettings.SMTPServer &&
+			*cfg.EmailSettings.SMTPPort == *a.Config().EmailSettings.SMTPPort &&
+			*cfg.EmailSettings.SMTPUsername == *a.Config().EmailSettings.SMTPUsername {
+			*cfg.EmailSettings.SMTPPassword = *a.Config().EmailSettings.SMTPPassword
 		} else {
 			return model.NewAppError("testEmail", "api.admin.test_email.reenter_password", nil, "", http.StatusBadRequest)
 		}