@winglibs/cdk8s v0.0.4

cdk8s support for Wing

This library is a custom Wing platform that can be used to synthesize Kubernetes YAML manifests through cdk8s constructs.

Prerequisites

• Wing CLI.

Installation

Install the Wing CLI:

npm i -g winglang

Create a new project and install this library:

mkdir wing-loves-cdk8s
cd wing-loves-cdk8s
npm i @winglibs/cdk8s

If you wish to use cdk8s-plus, you'll also need to install it (choose the relevant K8S version):

npm i cdk8s-plus-27

Usage

Let's define a Deployment resource with 3 replicas of the ubuntu public Docker image:

// ubuntu.main.w
bring "cdk8s-plus-27" as k8s;

let deployment = new k8s.Deployment(replicas: 3);
deployment.addContainer(image: "ubuntu");

Now, compile it to YAML:

$ wing compile -t @winglibs/cdk8s ubuntu.main.w
target/ubuntu.main.cdk8s

The output is a valid K8S YAML is in target/ubuntu.main.cdk8s:

$ ls target/ubuntu.main.cdk8s
chart-c86185a7.k8s.yaml

Here's a more interesting example:

bring "cdk8s-plus-27" as k8s;

// lets create a volume that contains our app.
let appData = new k8s.ConfigMap();
appData.addDirectory("./nodejs-app");

let appVolume = k8s.Volume.fromConfigMap(this, "App", appData);

// lets create a deployment to run a few instances of a pod
let deployment = new k8s.Deployment(
  replicas: 3,
);

// now we create a container that runs our app
let appPath = "/var/lib/app";
let port = 80;
let container = deployment.addContainer({
  image: "node:14.4.0-alpine3.12",
  command: ["node", "index.js", "{port}"],
  port: port,
  workingDir: appPath,
});

// make the app accessible to the container
container.mount(appPath, appVolume);

// finally, we expose the deployment as a load balancer service and make it run
deployment.exposeViaService(serviceType: k8s.ServiceType.LOAD_BALANCER);

Applying labels to all resources

You can use the WING_K8S_LABELS environment variable to apply labels to all resources in an app. The value is a JSON-encoded map.

export WING_K8S_LABELS='{ "my-label": "123", "your-label": "444" }'
wing compile -t @winglibs/cdk8s main.w

Roadmap

• Support generating Wing bindings from K8S API specifications and CRDs (cdk8s import).

Maintainers

• Elad Ben-Israel

License

This library is licensed under the MIT License.