feat: added example for informer with label selector

Author: StefanCenusa

examples/typescript/informer/informer-with-label-selector.ts

@@ -0,0 +1,83 @@
+// tslint:disable:no-console
+import * as k8s from '@kubernetes/client-node';
+
+const kc = new k8s.KubeConfig();
+kc.loadFromDefault();
+
+const k8sApi = kc.makeApiClient(k8s.CoreV1Api);
+
+const APP_LABEL_SELECTOR = 'app=foo';
+
+const listFn = () => k8sApi.listNamespacedPod(
+    'default',
+    undefined,
+    undefined,
+    undefined,
+    undefined,
+    APP_LABEL_SELECTOR,
+);
+
+const createPod = async (name, app) => {
+    const appPodContainer = {
+        name: 'nginx',
+        image: 'nginx:latest',
+    } as k8s.V1Container;
+
+    const appPod = {
+        metadata: {
+            name,
+            labels: {
+                app,
+            },
+        },
+        spec: {
+            containers: [appPodContainer],
+        },
+    } as k8s.V1Pod;
+    await k8sApi.createNamespacedPod('default', appPod).catch((e) => console.error(e));
+    console.log('create', name);
+};
+
+const deletePod = async (name, namespace) => {
+    await k8sApi.deleteNamespacedPod(name, namespace);
+    console.log('delete', name);
+};
+
+const delay = (ms) => {
+    return new Promise((resolve) => setTimeout(resolve, ms));
+};
+
+const informer = k8s.makeInformer(
+    kc,
+    '/api/v1/namespaces/default/pods',
+    listFn,
+    APP_LABEL_SELECTOR,
+);
+
+informer.on('add', (obj: k8s.V1Pod) => {
+    console.log(`Added: ${obj.metadata!.name}`);
+});
+informer.on('update', (obj: k8s.V1Pod) => {
+    console.log(`Updated: ${obj.metadata!.name}`);
+});
+informer.on('delete', (obj: k8s.V1Pod) => {
+    console.log(`Deleted: ${obj.metadata!.name}`);
+});
+informer.on('error', (err: k8s.V1Pod) => {
+    console.error(err);
+    // Restart informer after 5sec
+    setTimeout(() => {
+        informer.start();
+    }, 5000);
+});
+
+informer.start().then(() => {
+    setTimeout(async () => {
+        await createPod('server-foo', 'foo');
+        await delay(5000);
+        await createPod('server-bar', 'bar');
+        await delay(5000);
+        await deletePod('server-foo', 'default');
+        await deletePod('server-bar', 'default');
+    }, 5000);
+});