add custom search error

Signed-off-by: Emma Indal <emma.indahl@gmail.com>

plugins/search-backend-node/src/errors.ts

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2021 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { CustomErrorBase } from '@backstage/errors';
+
+/**
+ *  Failed to query documents for index that does not exist.
+ *  @public
+ */
+export class MissingIndexError extends CustomErrorBase {}

plugins/search-backend-node/src/index.ts

@@ -34,6 +34,7 @@ export type {
   RegisterCollatorParameters,
   RegisterDecoratorParameters,
 } from './types';
+export * from './errors';
 export * from './indexing';
 export * from './test-utils';