[MM-38082] Add local-mode handler for config reload endpoint (#18252)

* Add local-mode handler for config reload endpoint

* Remove redundant method

api4/config.go

@@ -86,12 +86,15 @@ func configReload(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if *c.App.Config().ExperimentalSettings.RestrictSystemAdmin {
+	if !c.AppContext.Session().IsUnrestricted() && *c.App.Config().ExperimentalSettings.RestrictSystemAdmin {
 		c.Err = model.NewAppError("configReload", "api.restricted_system_admin", nil, "", http.StatusBadRequest)
 		return
 	}
 
-	c.App.ReloadConfig()
+	if err := c.App.ReloadConfig(); err != nil {
+		c.Err = model.NewAppError("configReload", "api.config.reload_config.app_error", nil, err.Error(), http.StatusInternalServerError)
+		return
+	}
 
 	auditRec.Success()
 

api4/config_local.go

@@ -19,6 +19,7 @@ func (api *API) InitConfigLocal() {
 	api.BaseRoutes.APIRoot.Handle("/config", api.APILocal(localGetConfig)).Methods("GET")
 	api.BaseRoutes.APIRoot.Handle("/config", api.APILocal(localUpdateConfig)).Methods("PUT")
 	api.BaseRoutes.APIRoot.Handle("/config/patch", api.APILocal(localPatchConfig)).Methods("PUT")
+	api.BaseRoutes.APIRoot.Handle("/config/reload", api.APILocal(configReload)).Methods("POST")
 	api.BaseRoutes.APIRoot.Handle("/config/migrate", api.APILocal(migrateConfig)).Methods("POST")
 }
 

api4/config_test.go

@@ -126,10 +126,10 @@ func TestReloadConfig(t *testing.T) {
 		CheckForbiddenStatus(t, resp)
 	})
 
-	t.Run("as system admin", func(t *testing.T) {
-		_, err := th.SystemAdminClient.ReloadConfig()
+	th.TestForSystemAdminAndLocal(t, func(t *testing.T, client *model.Client4) {
+		_, err := client.ReloadConfig()
 		require.NoError(t, err)
-	})
+	}, "as system admin and local mode")
 
 	t.Run("as restricted system admin", func(t *testing.T) {
 		th.App.UpdateConfig(func(cfg *model.Config) { *cfg.ExperimentalSettings.RestrictSystemAdmin = true })