chore: implement parseEntityOrderFieldParams

Based on the implemntation in plugins/catalog-backend.

Signed-off-by: Marek Libra <marek.libra@gmail.com>

plugins/notifications-backend/src/service/parseEntityOrderFieldParams.test.ts

@@ -0,0 +1,57 @@
+/*
+ * Copyright 2024 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 { parseEntityOrderFieldParams } from './parseEntityOrderFieldParams';
+
+describe('parseEntityOrderFieldParams', () => {
+  it('supports no order fields', () => {
+    const result = parseEntityOrderFieldParams({});
+    expect(result).toEqual(undefined);
+  });
+
+  it('supports single orderField', () => {
+    const result = parseEntityOrderFieldParams({
+      orderField: ['metadata.name,desc'],
+    })!;
+    expect(result).toEqual([{ field: 'metadata.name', order: 'desc' }]);
+  });
+
+  it('supports single orderField without order', () => {
+    const result = parseEntityOrderFieldParams({
+      orderField: ['metadata.name'],
+    })!;
+    expect(result).toEqual([{ field: 'metadata.name' }]);
+  });
+
+  it('supports multiple order fields', () => {
+    const result = parseEntityOrderFieldParams({
+      orderField: ['metadata.name,desc', 'metadata.uid,asc'],
+    });
+
+    expect(result).toEqual([
+      { field: 'metadata.name', order: 'desc' },
+      { field: 'metadata.uid', order: 'asc' },
+    ]);
+  });
+
+  it('throws if orderField order is not valid', () => {
+    expect(() =>
+      parseEntityOrderFieldParams({
+        orderField: ['metadata.name,desc', 'metadata.uid,invalid'],
+      }),
+    ).toThrow(/Invalid order field order/);
+  });
+});

plugins/notifications-backend/src/service/parseEntityOrderFieldParams.ts

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2024 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.
+ */
+
+// This file is based on the plugins/catalog-backend
+
+import { InputError } from '@backstage/errors';
+import { EntityOrder } from '../database';
+
+/**
+ * Takes a single unknown parameter and makes sure that it's a single string or
+ * an array of strings, and returns as an array.
+ */
+export function parseStringsParam(
+  param: unknown,
+  ctx: string,
+): string[] | undefined {
+  if (param === undefined) {
+    return undefined;
+  }
+
+  const array = [param].flat();
+  if (array.some(p => typeof p !== 'string')) {
+    throw new InputError(`Invalid ${ctx}, not a string`);
+  }
+
+  return array as string[];
+}
+
+export function parseEntityOrderFieldParams(
+  params: Record<string, unknown>,
+): EntityOrder[] | undefined {
+  const orderFieldStrings = parseStringsParam(params.orderField, 'orderField');
+  if (!orderFieldStrings) {
+    return undefined;
+  }
+
+  return orderFieldStrings.map(orderFieldString => {
+    const [field, order] = orderFieldString.split(',');
+
+    if (order !== undefined && !isOrder(order)) {
+      throw new InputError('Invalid order field order, must be asc or desc');
+    }
+    return { field, order };
+  });
+}
+
+export function isOrder(order: string): order is 'asc' | 'desc' {
+  return ['asc', 'desc'].includes(order);
+}

plugins/notifications-backend/src/service/router.ts

@@ -45,7 +45,7 @@ import {
   Notification,
   NotificationReadSignal,
 } from '@backstage/plugin-notifications-common';
-import { parseEntityOrderFieldParams } from '@backstage/plugin-catalog-backend';
+import { parseEntityOrderFieldParams } from './parseEntityOrderFieldParams';
 
 /** @internal */
 export interface RouterOptions {