feat: add test and basic docs for catalog cluster locator

Signed-off-by: Jonah Back <jonah@jonahback.com>

docs/features/kubernetes/configuration.md

@@ -57,12 +57,17 @@ This is an array used to determine where to retrieve cluster configuration from.
 
 Valid cluster locator methods are:
 
+- [`catalog`](#catalog)
 - [`config`](#config)
 - [`gke`](#gke)
 - [custom `KubernetesClustersSupplier`](#custom-kubernetesclusterssupplier)
 
 #### `config`
 
+This cluster locator method will read cluster information from the catalog.
+
+#### `config`
+
 This cluster locator method will read cluster information from your app-config
 (see below).
 

packages/backend/src/plugins/kubernetes.ts

@@ -24,6 +24,7 @@ export default async function createPlugin(
   const { router } = await KubernetesBuilder.createBuilder({
     logger: env.logger,
     config: env.config,
+    discovery: env.discovery,
   }).build();
   return router;
 }

plugins/kubernetes-backend/src/cluster-locator/CatalogClusterLocator.test.ts

@@ -0,0 +1,56 @@
+/*
+ * Copyright 2020 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 '@backstage/backend-common';
+import { CatalogClusterLocator } from './CatalogClusterLocator';
+import { CatalogApi } from '@backstage/catalog-client';
+
+describe('CatalogClusterLocator', () => {
+  it('empty clusters returns empty cluster details', async () => {
+    const mockCatalogApi = {
+      getEntityByRef: jest.fn(),
+      getEntities: async () => ({
+        items: [
+          {
+            apiVersion: 'version',
+            kind: 'User',
+            metadata: {
+              annotations: {
+                'kubernetes.io/api-server': 'https://apiserver.com',
+                'kubernetes.io/api-server-certificate-authority': 'caData',
+                'kubernetes.io/auth-provider': 'aws',
+              },
+              name: 'owned',
+              namespace: 'default',
+            },
+          },
+        ],
+      }),
+    } as Partial<CatalogApi> as CatalogApi;
+
+    const sut = CatalogClusterLocator.fromConfig(mockCatalogApi);
+
+    const result = await sut.getClusters();
+
+    expect(result).toHaveLength(1);
+    expect(result[0]).toMatchObject({
+      name: 'owned',
+      url: 'https://apiserver.com',
+      caData: 'caData',
+      authProvider: 'aws',
+    });
+  });
+});

plugins/kubernetes-backend/src/cluster-locator/CatalogClusterLocator.ts

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020 The Backstage Authors
+ * Copyright 2022 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.
@@ -15,21 +15,17 @@
  */
 
 import { ClusterDetails, KubernetesClustersSupplier } from '../types/types';
-import {
-  CATALOG_FILTER_EXISTS,
-  CatalogClient,
-} from '@backstage/catalog-client';
-import { DiscoveryApi } from '@backstage/core-plugin-api';
+import { CATALOG_FILTER_EXISTS, CatalogApi } from '@backstage/catalog-client';
 
 export class CatalogClusterLocator implements KubernetesClustersSupplier {
-  private catalogClient: CatalogClient;
+  private catalogClient: CatalogApi;
 
-  constructor(catalogClient: CatalogClient) {
+  constructor(catalogClient: CatalogApi) {
     this.catalogClient = catalogClient;
   }
 
-  static fromConfig(discoveryApi: DiscoveryApi): CatalogClusterLocator {
-    return new CatalogClusterLocator(new CatalogClient({ discoveryApi }));
+  static fromConfig(catalogApi: CatalogApi): CatalogClusterLocator {
+    return new CatalogClusterLocator(catalogApi);
   }
 
   async getClusters(): Promise<ClusterDetails[]> {
@@ -55,13 +51,13 @@ export class CatalogClusterLocator implements KubernetesClustersSupplier {
         name: entity.metadata.name,
         // @ts-ignore filtered out by catalog-client query.
         url: entity.metadata.annotations['kubernetes.io/api-server'],
-        // @ts-ignore filtered out by catalog-client query.
         caData:
+          // @ts-ignore filtered out by catalog-client query.
           entity.metadata.annotations[
             'kubernetes.io/api-server-certificate-authority'
           ],
-        // @ts-ignore filtered out by catalog-client query.
         authProvider:
+          // @ts-ignore filtered out by catalog-client query.
           entity.metadata.annotations['kubernetes.io/auth-provider'],
       };
 

plugins/kubernetes-backend/src/cluster-locator/index.ts

@@ -19,6 +19,9 @@ import { Duration } from 'luxon';
 import { ClusterDetails, KubernetesClustersSupplier } from '../types/types';
 import { ConfigClusterLocator } from './ConfigClusterLocator';
 import { GkeClusterLocator } from './GkeClusterLocator';
+import { CatalogClusterLocator } from './CatalogClusterLocator';
+import { PluginEndpointDiscovery } from '@backstage/backend-common/dist';
+import { CatalogClient } from '@backstage/catalog-client';
 
 class CombinedClustersSupplier implements KubernetesClustersSupplier {
   constructor(readonly clusterSuppliers: KubernetesClustersSupplier[]) {}
@@ -38,13 +41,17 @@ class CombinedClustersSupplier implements KubernetesClustersSupplier {
 
 export const getCombinedClusterSupplier = (
   rootConfig: Config,
+  discovery: PluginEndpointDiscovery,
   refreshInterval: Duration | undefined = undefined,
 ): KubernetesClustersSupplier => {
+  const catalogClient = new CatalogClient({ discoveryApi: discovery });
   const clusterSuppliers = rootConfig
     .getConfigArray('kubernetes.clusterLocatorMethods')
     .map(clusterLocatorMethod => {
       const type = clusterLocatorMethod.getString('type');
       switch (type) {
+        case 'catalog':
+          return CatalogClusterLocator.fromConfig(catalogClient);
         case 'config':
           return ConfigClusterLocator.fromConfig(clusterLocatorMethod);
         case 'gke':

plugins/kubernetes-backend/src/service/KubernetesBuilder.ts

@@ -37,10 +37,12 @@ import {
   KubernetesFanOutHandler,
 } from './KubernetesFanOutHandler';
 import { KubernetesClientBasedFetcher } from './KubernetesFetcher';
+import { PluginEndpointDiscovery } from '@backstage/backend-common/dist';
 
 export interface KubernetesEnvironment {
   logger: Logger;
   config: Config;
+  discovery: PluginEndpointDiscovery;
 }
 
 /**
@@ -171,7 +173,11 @@ export class KubernetesBuilder {
     refreshInterval: Duration,
   ): KubernetesClustersSupplier {
     const config = this.env.config;
-    return getCombinedClusterSupplier(config, refreshInterval);
+    return getCombinedClusterSupplier(
+      config,
+      this.env.discovery,
+      refreshInterval,
+    );
   }
 
   protected buildObjectsProvider(