Installation

The Kubernetes feature is a plugin to Backstage, and it is exposed as a tab when viewing entities in the software catalog.

If you haven't set up Backstage already, read the Getting Started guide.

Adding the Kubernetes frontend plugin

The first step is to add the Kubernetes frontend plugin to your Backstage application.

From your Backstage root directory

yarn --cwd packages/app add @backstage/plugin-kubernetes

Once the package has been installed, you need to import the plugin in your app by adding the "Kubernetes" tab to the respective catalog pages.

packages/app/src/components/catalog/EntityPage.tsx

import { EntityKubernetesContent } from '@backstage/plugin-kubernetes';

// You can add the tab to any number of pages, the service page is shown as an
// example here
const serviceEntityPage = (
  <EntityLayout>
    {/* other tabs... */}
    <EntityLayout.Route path="/kubernetes" title="Kubernetes">
      <EntityKubernetesContent refreshIntervalMs={30000} />
    </EntityLayout.Route>
  </EntityLayout>
);

Note

The optional refreshIntervalMs property on the EntityKubernetesContent defines the interval in which the content automatically refreshes, if not set this will default to 10 seconds.

That's it! But now, we need the Kubernetes Backend plugin for the frontend to work.

Adding Kubernetes Backend plugin

First, we need to add the backend package:

From your Backstage root directory

yarn --cwd packages/backend add @backstage/plugin-kubernetes-backend

Then add it to your backend index.ts file:

packages/backend/src/index.ts

const backend = createBackend();

// Other plugins...

backend.add(import('@backstage/plugin-kubernetes-backend'));

backend.start();

That's it! The Kubernetes frontend and backend have now been added to your Backstage app.

Custom cluster discovery

If either existing cluster locators don't work for your use-case, it is possible to implement a custom KubernetesClustersSupplier.

Here's a very simplified example:

packages/backend/src/index.ts

import { createBackend } from '@backstage/backend-defaults';
import { createBackendModule } from '@backstage/backend-plugin-api';
import { Duration } from 'luxon';
import {
  ClusterDetails,
  KubernetesClustersSupplier,
  kubernetesClusterSupplierExtensionPoint,
} from '@backstage/plugin-kubernetes-node';

export class CustomClustersSupplier implements KubernetesClustersSupplier {
  constructor(private clusterDetails: ClusterDetails[] = []) {}

  static create(refreshInterval: Duration) {
    const clusterSupplier = new CustomClustersSupplier();
    // setup refresh, e.g. using a copy of https://github.com/backstage/backstage/blob/master/plugins/kubernetes-backend/src/service/runPeriodically.ts
    runPeriodically(
      () => clusterSupplier.refreshClusters(),
      refreshInterval.toMillis(),
    );
    return clusterSupplier;
  }

  async refreshClusters(): Promise<void> {
    this.clusterDetails = []; // fetch from somewhere
  }

  async getClusters(): Promise<ClusterDetails[]> {
    return this.clusterDetails;
  }
}

const backend = createBackend();

export const kubernetesModuleCustomClusterDiscovery = createBackendModule({
  pluginId: 'kubernetes',
  moduleId: 'custom-cluster-discovery',
  register(env) {
    env.registerInit({
      deps: {
        kubernetes: kubernetesClusterSupplierExtensionPoint,
      },
      async init({ kubernetes }) {
        kubernetes.addClusterSupplier(
          CustomClustersSupplier.create(Duration.fromObject({ minutes: 60 })),
        );
      },
    });
  },
});

// Other plugins...
backend.add(import('@backstage/plugin-kubernetes-backend'));
backend.add(kubernetesModuleCustomClusterDiscovery);

backend.start();

Note

This example uses items from the @backstage/plugin-kubernetes-node and luxon packages, you'll need to add those for this example to work as is.

Configuration

After installing the plugins in the code, you'll need to then configure them.

Troubleshooting

After installing the plugins in the code, if the Kubernetes information is not showing up, you'll need to troubleshoot it.