Creating extension point for kubernetesObjectsProvider

Signed-off-by: Andres Mauricio Gomez P <andmagom@outlook.com>

.changeset/nice-ghosts-build.md

@@ -0,0 +1,6 @@
+---
+'@backstage/plugin-kubernetes-node': minor
+'@backstage/plugin-kubernetes-backend': patch
+---
+
+A new Package is introduced to house the backend plugin's extension points for Kubernetes plugin, at the moment only the KubernetesObjectsProviderExtensionPoint is present. The Kubernetes-backed package was modified to use this new extension point

plugins/kubernetes-backend/package.json

@@ -61,6 +61,7 @@
     "@backstage/plugin-auth-node": "workspace:^",
     "@backstage/plugin-catalog-node": "workspace:^",
     "@backstage/plugin-kubernetes-common": "workspace:^",
+    "@backstage/plugin-kubernetes-node": "workspace:^",
     "@backstage/plugin-permission-common": "workspace:^",
     "@backstage/plugin-permission-node": "workspace:^",
     "@backstage/types": "workspace:^",

plugins/kubernetes-backend/src/plugin.ts

@@ -21,15 +21,46 @@ import {
 } from '@backstage/backend-plugin-api';
 import { catalogServiceRef } from '@backstage/plugin-catalog-node/alpha';
 
-import { KubernetesBuilder } from '@backstage/plugin-kubernetes-backend';
+import {
+  KubernetesBuilder,
+  KubernetesObjectsProvider,
+} from '@backstage/plugin-kubernetes-backend';
+import {
+  KubernetesObjectsProviderExtensionPoint,
+  kubernetesObjectsProviderExtensionPoint,
+} from '@backstage/plugin-kubernetes-node';
+
+class ObjectsProvider implements KubernetesObjectsProviderExtensionPoint {
+  private objectsProvider: KubernetesObjectsProvider | undefined;
+
+  getObjectsProvider() {
+    return this.objectsProvider;
+  }
+
+  addObjectsProvider(provider: KubernetesObjectsProvider) {
+    if (this.objectsProvider) {
+      throw new Error(
+        'Multiple Kubernetes objects provider is not supported at this time',
+      );
+    }
+    this.objectsProvider = provider;
+  }
+}
 
 /**
  * This is the backend plugin that provides the Kubernetes integration.
  * @alpha
  */
+
 export const kubernetesPlugin = createBackendPlugin({
   pluginId: 'kubernetes',
   register(env) {
+    const extensionPoint = new ObjectsProvider();
+    env.registerExtensionPoint(
+      kubernetesObjectsProviderExtensionPoint,
+      extensionPoint,
+    );
+
     env.registerInit({
       deps: {
         http: coreServices.httpRouter,
@@ -46,7 +77,9 @@ export const kubernetesPlugin = createBackendPlugin({
           config,
           catalogApi,
           permissions,
-        }).build();
+        })
+          .setObjectsProvider(extensionPoint.getObjectsProvider())
+          .build();
         http.use(router);
       },
     });

plugins/kubernetes-node/.eslintrc.js

@@ -0,0 +1 @@
+module.exports = require('@backstage/cli/config/eslint-factory')(__dirname);

plugins/kubernetes-node/README.md

@@ -0,0 +1,5 @@
+# @backstage/plugin-kubernetes-node
+
+Welcome to the Node.js library package for the kubernetes plugin!
+
+_This plugin was created through the Backstage CLI_

plugins/kubernetes-node/api-report.md

@@ -0,0 +1,17 @@
+## API Report File for "@backstage/plugin-kubernetes-node"
+
+> Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
+
+```ts
+import { ExtensionPoint } from '@backstage/backend-plugin-api';
+import { KubernetesObjectsProvider } from '@backstage/plugin-kubernetes-backend';
+
+// @public
+export interface KubernetesObjectsProviderExtensionPoint {
+  // (undocumented)
+  addObjectsProvider(provider: KubernetesObjectsProvider): void;
+}
+
+// @public
+export const kubernetesObjectsProviderExtensionPoint: ExtensionPoint<KubernetesObjectsProviderExtensionPoint>;
+```

plugins/kubernetes-node/catalog-info.yaml

@@ -0,0 +1,10 @@
+apiVersion: backstage.io/v1alpha1
+kind: Component
+metadata:
+  name: backstage-plugin-kubernetes-node
+  title: '@backstage/plugin-kubernetes-node'
+  description: Node.js library for the kubernetes plugin
+spec:
+  lifecycle: experimental
+  type: backstage-node-library
+  owner: kubernetes-maintainers

plugins/kubernetes-node/package.json

@@ -0,0 +1,34 @@
+{
+  "name": "@backstage/plugin-kubernetes-node",
+  "description": "Node.js library for the kubernetes plugin",
+  "version": "0.0.0",
+  "main": "src/index.ts",
+  "types": "src/index.ts",
+  "license": "Apache-2.0",
+  "publishConfig": {
+    "access": "public",
+    "main": "dist/index.cjs.js",
+    "types": "dist/index.d.ts"
+  },
+  "backstage": {
+    "role": "node-library"
+  },
+  "scripts": {
+    "build": "backstage-cli package build",
+    "lint": "backstage-cli package lint",
+    "test": "backstage-cli package test",
+    "clean": "backstage-cli package clean",
+    "prepack": "backstage-cli package prepack",
+    "postpack": "backstage-cli package postpack"
+  },
+  "devDependencies": {
+    "@backstage/cli": "workspace:^"
+  },
+  "files": [
+    "dist"
+  ],
+  "dependencies": {
+    "@backstage/backend-plugin-api": "workspace:^",
+    "@backstage/plugin-kubernetes-backend": "workspace:^"
+  }
+}

plugins/kubernetes-node/src/extensions.ts

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2023 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 { createExtensionPoint } from '@backstage/backend-plugin-api';
+import { KubernetesObjectsProvider } from '@backstage/plugin-kubernetes-backend';
+
+/**
+ * The interface for {@link kubernetesObjectsProviderExtensionPoint}.
+ *
+ * @public
+ */
+export interface KubernetesObjectsProviderExtensionPoint {
+  addObjectsProvider(provider: KubernetesObjectsProvider): void;
+}
+
+/**
+ * An extension point the exposes the ability to configure a objects provider.
+ *
+ * @public
+ */
+export const kubernetesObjectsProviderExtensionPoint =
+  createExtensionPoint<KubernetesObjectsProviderExtensionPoint>({
+    id: 'kubernetes.objects-provider',
+  });

plugins/kubernetes-node/src/index.ts

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2023 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.
+ */
+
+/**
+ * Node.js library for the kubernetes plugin.
+ *
+ * @packageDocumentation
+ */
+
+// In this package you might for example export functions that
+// help other plugins or modules interact with your plugin.
+
+/**
+ * Node.js library for the kubernetes plugin.
+ *
+ * @packageDocumentation
+ */
+
+export {
+  kubernetesObjectsProviderExtensionPoint,
+  type KubernetesObjectsProviderExtensionPoint,
+} from './extensions';

plugins/kubernetes-node/src/setupTests.ts

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2023 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.
+ */
+export {};

yarn.lock

@@ -7570,6 +7570,7 @@ __metadata:
     "@backstage/plugin-auth-node": "workspace:^"
     "@backstage/plugin-catalog-node": "workspace:^"
     "@backstage/plugin-kubernetes-common": "workspace:^"
+    "@backstage/plugin-kubernetes-node": "workspace:^"
     "@backstage/plugin-permission-common": "workspace:^"
     "@backstage/plugin-permission-node": "workspace:^"
     "@backstage/types": "workspace:^"
@@ -7702,6 +7703,16 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@backstage/plugin-kubernetes-node@workspace:^, @backstage/plugin-kubernetes-node@workspace:plugins/kubernetes-node":
+  version: 0.0.0-use.local
+  resolution: "@backstage/plugin-kubernetes-node@workspace:plugins/kubernetes-node"
+  dependencies:
+    "@backstage/backend-plugin-api": "workspace:^"
+    "@backstage/cli": "workspace:^"
+    "@backstage/plugin-kubernetes-backend": "workspace:^"
+  languageName: unknown
+  linkType: soft
+
 "@backstage/plugin-kubernetes@workspace:^, @backstage/plugin-kubernetes@workspace:plugins/kubernetes":
   version: 0.0.0-use.local
   resolution: "@backstage/plugin-kubernetes@workspace:plugins/kubernetes"