Creating extension point for kubernetesFetcher

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

plugins/kubernetes-node/src/extensions.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 import { createExtensionPoint } from '@backstage/backend-plugin-api';
+import { KubernetesFetcher } from '@backstage/plugin-kubernetes-backend';
 import { AuthenticationStrategy } from '@backstage/plugin-kubernetes-node';
 import { KubernetesClustersSupplier } from '@backstage/plugin-kubernetes-node';
 import { KubernetesObjectsProvider } from '@backstage/plugin-kubernetes-node';
@@ -74,3 +75,22 @@ export const kubernetesAuthStrategyExtensionPoint =
   createExtensionPoint<KubernetesAuthStrategyExtensionPoint>({
     id: 'kubernetes.auth-strategy',
   });
+
+/**
+ * The interface for {@link kubernetesFetcherExtensionPoint}.
+ *
+ * @public
+ */
+export interface KubernetesFetcherExtensionPoint {
+  addFetcher(fetcher: KubernetesFetcher): void;
+}
+
+/**
+ * An extension point the exposes the ability to configure a kubernetes fetcher.
+ *
+ * @public
+ */
+export const kubernetesFetcherExtensionPoint =
+  createExtensionPoint<KubernetesFetcherExtensionPoint>({
+    id: 'kubernetes.fetcher',
+  });

plugins/kubernetes-node/src/index.ts

@@ -29,13 +29,5 @@
  * @packageDocumentation
  */
 
-export {
-  kubernetesObjectsProviderExtensionPoint,
-  type KubernetesObjectsProviderExtensionPoint,
-  kubernetesClusterSupplierExtensionPoint,
-  type KubernetesClusterSupplierExtensionPoint,
-  kubernetesAuthStrategyExtensionPoint,
-  type KubernetesAuthStrategyExtensionPoint,
-} from './extensions';
-
+export * from './extensions';
 export * from './types';

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

@@ -14,8 +14,11 @@
  * limitations under the License.
  */
 import { Entity } from '@backstage/catalog-model';
+import { KubernetesObjectTypes } from '@backstage/plugin-kubernetes-backend';
 import {
   CustomResourceMatcher,
+  FetchResponse,
+  KubernetesFetchError,
   KubernetesRequestAuth,
   ObjectsByEntityResponse,
 } from '@backstage/plugin-kubernetes-common';
@@ -150,3 +153,62 @@ export interface AuthenticationStrategy {
   ): Promise<KubernetesCredential>;
   validateCluster(authMetadata: AuthMetadata): Error[];
 }
+
+/**
+ *
+ * @public
+ */
+export interface ObjectToFetch {
+  objectType: KubernetesObjectTypes; // TODO - Review
+  group: string;
+  apiVersion: string;
+  plural: string;
+}
+
+/**
+ *
+ * @public
+ */
+export interface CustomResource extends ObjectToFetch {
+  objectType: 'customresources';
+}
+
+/**
+ *
+ * @public
+ */
+export interface ObjectFetchParams {
+  serviceId: string;
+  clusterDetails: ClusterDetails;
+  credential: KubernetesCredential;
+  objectTypesToFetch: Set<ObjectToFetch>;
+  labelSelector?: string;
+  customResources: CustomResource[];
+  namespace?: string;
+}
+
+/**
+ *
+ * @public
+ */
+export interface FetchResponseWrapper {
+  errors: KubernetesFetchError[];
+  responses: FetchResponse[];
+}
+
+/**
+ * Fetches information from a kubernetes cluster using the cluster details object to target a specific cluster
+ *
+ * @public
+ */
+export interface KubernetesFetcher {
+  fetchObjectsForService(
+    params: ObjectFetchParams,
+  ): Promise<FetchResponseWrapper>;
+  fetchPodMetricsByNamespaces(
+    clusterDetails: ClusterDetails,
+    credential: KubernetesCredential,
+    namespaces: Set<string>,
+    labelSelector?: string,
+  ): Promise<FetchResponseWrapper>;
+}