Creating extension point for kubernetesClusterSupplier

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

.changeset/plenty-falcons-travel.md

@@ -0,0 +1,6 @@
+---
+'@backstage/plugin-kubernetes-node': minor
+'@backstage/plugin-kubernetes-backend': patch
+---
+
+The `kubernetes-node` plugin has been modified to house a new extension points for Kubernetes backend plugin; `KubernetesClusterSupplierExtensionPoint` is introduced . The `kubernetes-backend` plugin was modified to use this new extension point.

plugins/kubernetes-backend/src/plugin.ts

@@ -26,6 +26,9 @@ import {
   KubernetesObjectsProviderExtensionPoint,
   kubernetesObjectsProviderExtensionPoint,
   KubernetesObjectsProvider,
+  KubernetesClusterSupplierExtensionPoint,
+  kubernetesClusterSupplierExtensionPoint,
+  KubernetesClustersSupplier,
 } from '@backstage/plugin-kubernetes-node';
 
 class ObjectsProvider implements KubernetesObjectsProviderExtensionPoint {
@@ -45,6 +48,23 @@ class ObjectsProvider implements KubernetesObjectsProviderExtensionPoint {
   }
 }
 
+class ClusterSuplier implements KubernetesClusterSupplierExtensionPoint {
+  private clusterSupplier: KubernetesClustersSupplier | undefined;
+
+  getClusterSupplier() {
+    return this.clusterSupplier;
+  }
+
+  addClusterSupplier(clusterSupplier: KubernetesClustersSupplier) {
+    if (this.clusterSupplier) {
+      throw new Error(
+        'Multiple Kubernetes Cluster Suppliers is not supported at this time',
+      );
+    }
+    this.clusterSupplier = clusterSupplier;
+  }
+}
+
 /**
  * This is the backend plugin that provides the Kubernetes integration.
  * @alpha
@@ -53,10 +73,15 @@ class ObjectsProvider implements KubernetesObjectsProviderExtensionPoint {
 export const kubernetesPlugin = createBackendPlugin({
   pluginId: 'kubernetes',
   register(env) {
-    const extensionPoint = new ObjectsProvider();
+    const extPointObjectsProvider = new ObjectsProvider();
+    const extPointClusterSuplier = new ClusterSuplier();
     env.registerExtensionPoint(
       kubernetesObjectsProviderExtensionPoint,
-      extensionPoint,
+      extPointObjectsProvider,
+    );
+    env.registerExtensionPoint(
+      kubernetesClusterSupplierExtensionPoint,
+      extPointClusterSuplier,
     );
 
     env.registerInit({
@@ -76,7 +101,8 @@ export const kubernetesPlugin = createBackendPlugin({
           catalogApi,
           permissions,
         })
-          .setObjectsProvider(extensionPoint.getObjectsProvider())
+          .setObjectsProvider(extPointObjectsProvider.getObjectsProvider())
+          .setClusterSupplier(extPointClusterSuplier.getClusterSupplier())
           .build();
         http.use(router);
       },

plugins/kubernetes-backend/src/types/index.ts

@@ -17,7 +17,10 @@
 export * from './types';
 
 export type {
+  AuthMetadata,
+  ClusterDetails,
   CustomResourcesByEntity,
+  KubernetesClustersSupplier,
   KubernetesObjectsByEntity,
   KubernetesObjectsProvider,
 } from '@backstage/plugin-kubernetes-node';

plugins/kubernetes-backend/src/types/types.ts

@@ -16,7 +16,6 @@
 
 import { Entity } from '@backstage/catalog-model';
 import { Logger } from 'winston';
-import type { JsonObject } from '@backstage/types';
 import type {
   CustomResourceMatcher,
   FetchResponse,
@@ -25,6 +24,7 @@ import type {
 } from '@backstage/plugin-kubernetes-common';
 import { Config } from '@backstage/config';
 import { KubernetesCredential } from '../auth/types';
+import { ClusterDetails } from '@backstage/plugin-kubernetes-node';
 
 /**
  *
@@ -107,20 +107,6 @@ export type KubernetesObjectTypes =
 // If updating this list, also make sure to update
 // `objectTypes` and `apiVersionOverrides` in config.d.ts!
 
-/**
- * Used to load cluster details from different sources
- * @public
- */
-export interface KubernetesClustersSupplier {
-  /**
-   * Returns the cached list of clusters.
-   *
-   * Implementations _should_ cache the clusters and refresh them periodically,
-   * as getClusters is called whenever the list of clusters is needed.
-   */
-  getClusters(): Promise<ClusterDetails[]>;
-}
-
 /**
  * @public
  */
@@ -146,70 +132,6 @@ export interface KubernetesServiceLocator {
  */
 export type ServiceLocatorMethod = 'multiTenant' | 'singleTenant' | 'http'; // TODO implement http
 
-/**
- * Provider-specific authentication configuration
- * @public
- */
-export type AuthMetadata = Record<string, string>;
-
-/**
- *
- * @public
- */
-export interface ClusterDetails {
-  /**
-   * Specifies the name of the Kubernetes cluster.
-   */
-  name: string;
-  url: string;
-  authMetadata: AuthMetadata;
-  skipTLSVerify?: boolean;
-  /**
-   * Whether to skip the lookup to the metrics server to retrieve pod resource usage.
-   * It is not guaranteed that the Kubernetes distro has the metrics server installed.
-   */
-  skipMetricsLookup?: boolean;
-  caData?: string | undefined;
-  caFile?: string | undefined;
-  /**
-   * Specifies the link to the Kubernetes dashboard managing this cluster.
-   * @remarks
-   * Note that you should specify the app used for the dashboard
-   * using the dashboardApp property, in order to properly format
-   * links to kubernetes resources, otherwise it will assume that you're running the standard one.
-   * @see dashboardApp
-   * @see dashboardParameters
-   */
-  dashboardUrl?: string;
-  /**
-   * Specifies the app that provides the Kubernetes dashboard.
-   * This will be used for formatting links to kubernetes objects inside the dashboard.
-   * @remarks
-   * The existing apps are: standard, rancher, openshift, gke, aks, eks
-   * Note that it will default to the regular dashboard provided by the Kubernetes project (standard).
-   * Note that you can add your own formatter by registering it to the clusterLinksFormatters dictionary.
-   * @defaultValue standard
-   * @see dashboardUrl
-   * @example
-   * ```ts
-   * import { clusterLinksFormatters } from '@backstage/plugin-kubernetes';
-   * clusterLinksFormatters.myDashboard = (options) => ...;
-   * ```
-   */
-  dashboardApp?: string;
-  /**
-   * Specifies specific parameters used by some dashboard URL formatters.
-   * This is used by the GKE formatter which requires the project, region and cluster name.
-   * @see dashboardApp
-   */
-  dashboardParameters?: JsonObject;
-  /**
-   * Specifies which custom resources to look for when returning an entity's
-   * Kubernetes resources.
-   */
-  customResources?: CustomResourceMatcher[];
-}
-
 /**
  *
  * @public

plugins/kubernetes-node/package.json

@@ -30,6 +30,7 @@
   "dependencies": {
     "@backstage/backend-plugin-api": "workspace:^",
     "@backstage/catalog-model": "workspace:^",
-    "@backstage/plugin-kubernetes-common": "workspace:^"
+    "@backstage/plugin-kubernetes-common": "workspace:^",
+    "@backstage/types": "workspace:^"
   }
 }

plugins/kubernetes-node/src/extensions.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 import { createExtensionPoint } from '@backstage/backend-plugin-api';
+import { KubernetesClustersSupplier } from '@backstage/plugin-kubernetes-node';
 import { KubernetesObjectsProvider } from '@backstage/plugin-kubernetes-node';
 
 /**
@@ -34,3 +35,22 @@ export const kubernetesObjectsProviderExtensionPoint =
   createExtensionPoint<KubernetesObjectsProviderExtensionPoint>({
     id: 'kubernetes.objects-provider',
   });
+
+/**
+ * The interface for {@link kubernetesClusterSupplierExtensionPoint}.
+ *
+ * @public
+ */
+export interface KubernetesClusterSupplierExtensionPoint {
+  addClusterSupplier(clusterSupplier: KubernetesClustersSupplier): void;
+}
+
+/**
+ * An extension point the exposes the ability to configure a cluster supplier.
+ *
+ * @public
+ */
+export const kubernetesClusterSupplierExtensionPoint =
+  createExtensionPoint<KubernetesClusterSupplierExtensionPoint>({
+    id: 'kubernetes.cluster-supplier',
+  });

plugins/kubernetes-node/src/index.ts

@@ -32,6 +32,8 @@
 export {
   kubernetesObjectsProviderExtensionPoint,
   type KubernetesObjectsProviderExtensionPoint,
+  kubernetesClusterSupplierExtensionPoint,
+  type KubernetesClusterSupplierExtensionPoint,
 } from './extensions';
 
 export * from './types';

plugins/kubernetes-node/src/types/types.ts

@@ -19,6 +19,7 @@ import {
   KubernetesRequestAuth,
   ObjectsByEntityResponse,
 } from '@backstage/plugin-kubernetes-common';
+import { JsonObject } from '@backstage/types';
 
 /**
  *
@@ -51,3 +52,81 @@ export interface KubernetesObjectsByEntity {
 export interface CustomResourcesByEntity extends KubernetesObjectsByEntity {
   customResources: CustomResourceMatcher[];
 }
+
+/**
+ * Provider-specific authentication configuration
+ * @public
+ */
+export type AuthMetadata = Record<string, string>;
+
+/**
+ *
+ * @public
+ */
+export interface ClusterDetails {
+  /**
+   * Specifies the name of the Kubernetes cluster.
+   */
+  name: string;
+  url: string;
+  authMetadata: AuthMetadata;
+  skipTLSVerify?: boolean;
+  /**
+   * Whether to skip the lookup to the metrics server to retrieve pod resource usage.
+   * It is not guaranteed that the Kubernetes distro has the metrics server installed.
+   */
+  skipMetricsLookup?: boolean;
+  caData?: string | undefined;
+  caFile?: string | undefined;
+  /**
+   * Specifies the link to the Kubernetes dashboard managing this cluster.
+   * @remarks
+   * Note that you should specify the app used for the dashboard
+   * using the dashboardApp property, in order to properly format
+   * links to kubernetes resources, otherwise it will assume that you're running the standard one.
+   * @see dashboardApp
+   * @see dashboardParameters
+   */
+  dashboardUrl?: string;
+  /**
+   * Specifies the app that provides the Kubernetes dashboard.
+   * This will be used for formatting links to kubernetes objects inside the dashboard.
+   * @remarks
+   * The existing apps are: standard, rancher, openshift, gke, aks, eks
+   * Note that it will default to the regular dashboard provided by the Kubernetes project (standard).
+   * Note that you can add your own formatter by registering it to the clusterLinksFormatters dictionary.
+   * @defaultValue standard
+   * @see dashboardUrl
+   * @example
+   * ```ts
+   * import { clusterLinksFormatters } from '@backstage/plugin-kubernetes';
+   * clusterLinksFormatters.myDashboard = (options) => ...;
+   * ```
+   */
+  dashboardApp?: string;
+  /**
+   * Specifies specific parameters used by some dashboard URL formatters.
+   * This is used by the GKE formatter which requires the project, region and cluster name.
+   * @see dashboardApp
+   */
+  dashboardParameters?: JsonObject;
+  /**
+   * Specifies which custom resources to look for when returning an entity's
+   * Kubernetes resources.
+   */
+  customResources?: CustomResourceMatcher[];
+}
+
+/**
+ * Used to load cluster details from different sources
+ * @public
+ */
+export interface KubernetesClustersSupplier {
+  /**
+   * Returns the cached list of clusters.
+   *
+   * Implementations _should_ cache the clusters and refresh them periodically,
+   * as getClusters is called whenever the list of clusters is needed.
+   */
+  getClusters(): Promise<ClusterDetails[]>;
+}

yarn.lock

@@ -7673,6 +7673,7 @@ __metadata:
     "@backstage/catalog-model": "workspace:^"
     "@backstage/cli": "workspace:^"
     "@backstage/plugin-kubernetes-common": "workspace:^"
+    "@backstage/types": "workspace:^"
   languageName: unknown
   linkType: soft