docs(apply): doc pattern for kubectl apply -f (#305)

Closes #64

Author: cfellin1

README.md

@@ -126,6 +126,7 @@ specifications:
 [examples/](examples/) has snippets for using kubernetes-client:
 
 * The basic usage example from above: [basic.js](./examples/basic.js)
+* Use error handling to simulate `kubectl apply -f`: [apply-deploy.js](./examples/apply-deploy.js)
 * Create a `client` from your kube-apiserver's swagger.json:
   [client-from-apiserver-swagger.js](./examples/client-from-apiserver-swagger.js)
 * Create a `client` from one of the included Swagger specifications:

examples/apply-deploy.js

@@ -0,0 +1,22 @@
+//
+// Use this pattern to simulate kubectl apply -f; create a Deployment or replace it if it already exists.
+//
+const Client = require('kubernetes-client').Client;
+const config = require('kubernetes-client').config;
+
+const deploymentManifest = require('./nginx-deployment.json');
+
+async function applyDeploy() {
+  const client = new Client({ config: config.fromKubeconfig(), version: '1.9' });
+  
+  try {
+    const create = await client.apis.apps.v1.namespaces('default').deployments.post({ body: deploymentManifest });
+    console.log('Create:', create);
+  } catch (err) {
+    if (err.code !== 409) throw err;
+    const replace = await client.apis.apps.v1.namespaces('default').deployments('nginx-deployment').put({ body: deploymentManifest });
+    console.log('Replace:', replace);
+  }
+}
+
+applyDeploy();