feat: support new backend system at explore-backend

Add the backend plugin `explorePlugin` as default export
that registers the router for the explore backend
with the `StaticExploreToolProvider` loading its data
from the config `explore.tools`.

Signed-off-by: Patrick Jungermann <Patrick.Jungermann@gmail.com>

.changeset/cyan-icons-rest.md

@@ -0,0 +1,14 @@
+---
+'@backstage/plugin-explore-backend': patch
+---
+
+Add support for the new backend system.
+
+A new backend plugin for the explore backend
+was added and exported as `default`.
+
+You can use it with the new backend system like
+
+```ts title="packages/backend/src/index.ts"
+backend.add(import('@backstage/plugin-explore-backend'));
+```

plugins/explore-backend/README.md

@@ -9,6 +9,36 @@ for these tools.
 
 ### Adding the plugin to your `packages/backend`
 
+Install dependencies
+
+```bash
+# From your Backstage root directory
+yarn add --cwd packages/backend @backstage/plugin-explore-backend
+```
+
+Add feature
+
+```ts title="packages/backend/src/index.ts"
+backend.add(import('@backstage/plugin-explore-backend'));
+```
+
+Config:
+
+```yaml
+explore:
+  tools:
+    - title: New Relic
+      description: new relic plugin
+      url: /newrelic
+      image: https://i.imgur.com/L37ikrX.jpg
+      tags:
+        - newrelic
+        - proxy
+        - nerdGraph
+```
+
+### Adding the plugin to your `packages/backend` (old)
+
 #### Tools as Config
 
 Install dependencies

plugins/explore-backend/api-report.md

@@ -3,6 +3,7 @@
 > Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
 
 ```ts
+import { BackendFeature } from '@backstage/backend-plugin-api';
 import { Config } from '@backstage/config';
 import { ExploreTool } from '@backstage/plugin-explore-common';
 import express from 'express';
@@ -16,6 +17,10 @@ import type { ToolDocumentCollatorFactoryOptions as ToolDocumentCollatorFactoryO
 // @public (undocumented)
 export function createRouter(options: RouterOptions): Promise<express.Router>;
 
+// @public
+const explorePlugin: () => BackendFeature;
+export default explorePlugin;
+
 // @public (undocumented)
 export interface ExploreToolProvider {
   getTools(request: GetExploreToolsRequest): Promise<GetExploreToolsResponse>;

plugins/explore-backend/package.json

@@ -29,6 +29,7 @@
   },
   "dependencies": {
     "@backstage/backend-common": "workspace:^",
+    "@backstage/backend-plugin-api": "workspace:^",
     "@backstage/config": "workspace:^",
     "@backstage/plugin-explore-common": "workspace:^",
     "@backstage/plugin-search-backend-module-explore": "workspace:^",
@@ -42,6 +43,7 @@
     "yn": "^4.0.0"
   },
   "devDependencies": {
+    "@backstage/backend-test-utils": "workspace:^",
     "@backstage/cli": "workspace:^",
     "@types/supertest": "^2.0.8",
     "supertest": "^6.2.4"

plugins/explore-backend/src/index.ts

@@ -20,6 +20,7 @@
  * @packageDocumentation
  */
 
+export { explorePlugin as default } from './plugin';
 export * from './service';
 export * from './tools';
 

plugins/explore-backend/src/plugin.test.ts

@@ -0,0 +1,50 @@
+/*
+ * 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 { mockServices, startTestBackend } from '@backstage/backend-test-utils';
+import { ExploreTool } from '@backstage/plugin-explore-common';
+import { explorePlugin } from './plugin';
+
+describe('explorePlugin', () => {
+  it('should register explore plugin and its router', async () => {
+    const tool: ExploreTool = {
+      title: 'Tool Title',
+      image: 'https://example.com/image.png',
+      url: 'https://example.com',
+      lifecycle: 'production',
+      tags: ['tag1', 'tag2'],
+    };
+
+    const httpRouterMock = mockServices.httpRouter.mock();
+
+    await startTestBackend({
+      extensionPoints: [],
+      features: [
+        explorePlugin(),
+        httpRouterMock.factory,
+        mockServices.rootConfig.factory({
+          data: {
+            explore: {
+              tools: [tool],
+            },
+          },
+        }),
+      ],
+    });
+
+    expect(httpRouterMock.use).toHaveBeenCalledTimes(1);
+  });
+});

plugins/explore-backend/src/plugin.ts

@@ -0,0 +1,49 @@
+/*
+ * 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 { loggerToWinstonLogger } from '@backstage/backend-common';
+import {
+  coreServices,
+  createBackendPlugin,
+} from '@backstage/backend-plugin-api';
+import { createRouter } from './service';
+import { StaticExploreToolProvider } from './tools';
+
+/**
+ * The explore backend plugin.
+ *
+ * @public
+ */
+export const explorePlugin = createBackendPlugin({
+  pluginId: 'explore',
+  register(env) {
+    env.registerInit({
+      deps: {
+        config: coreServices.rootConfig,
+        httpRouter: coreServices.httpRouter,
+        logger: coreServices.logger,
+      },
+      async init({ config, httpRouter, logger }) {
+        httpRouter.use(
+          await createRouter({
+            logger: loggerToWinstonLogger(logger),
+            toolProvider: StaticExploreToolProvider.fromConfig(config),
+          }),
+        );
+      },
+    });
+  },
+});

yarn.lock

@@ -6412,6 +6412,8 @@ __metadata:
   resolution: "@backstage/plugin-explore-backend@workspace:plugins/explore-backend"
   dependencies:
     "@backstage/backend-common": "workspace:^"
+    "@backstage/backend-plugin-api": "workspace:^"
+    "@backstage/backend-test-utils": "workspace:^"
     "@backstage/cli": "workspace:^"
     "@backstage/config": "workspace:^"
     "@backstage/plugin-explore-common": "workspace:^"