feat(stacks): add a setting to disable the creation of stacks for non-admin users (#3932)

* feat(settings): introduce a setting to prevent non-admin from stack creation

* feat(settings): update stack creation setting

* feat(settings): fail stack creation if user is non admin

* fix(settings): save preventStackCreation setting to state

* feat(stacks): disable add button when settings is enabled

* format(stacks): remove line

* feat(stacks): setting to hide stacks from users

* feat(settings): rename disable stacks setting

* refactor(settings): rename setting to disableStackManagementForRegularUsers

api/http/handler/stacks/handler.go

@@ -87,3 +87,27 @@ func (handler *Handler) userCanAccessStack(securityContext *security.RestrictedR
 	}
 	return false, nil
 }
+
+func (handler *Handler) userCanCreateStack(securityContext *security.RestrictedRequestContext, endpointID portainer.EndpointID) (bool, error) {
+	if securityContext.IsAdmin {
+		return true, nil
+	}
+
+	_, err := handler.ExtensionService.Extension(portainer.RBACExtension)
+	if err == portainer.ErrObjectNotFound {
+		return false, nil
+	} else if err != nil && err != portainer.ErrObjectNotFound {
+		return false, err
+	}
+
+	user, err := handler.UserService.User(securityContext.UserID)
+	if err != nil {
+		return false, err
+	}
+
+	_, ok := user.EndpointAuthorizations[endpointID][portainer.EndpointResourcesAccess]
+	if ok {
+		return true, nil
+	}
+	return false, nil
+}