K8s Manifest to GruCloud Code

This code generator takes any kubernetes YAML manifests and creates the corresponding resources written with the GruCloud Javascript SDK.

Currently used to create the following kubernetes modules:

• Cert Manager
• Aws Load Balancer Controller
• Web Ui Dashboard
• Crunchy Postgres Operator
• Prometheus

k8s-manifest2code supports reading from a single file, recursively from a directory, and from HTTPS.

Tutorial: How to create a Kubernetes Module with k8s-manifest2code

We'll create a web ui dashboard grucloud module and its example with the help of the k8s-manifest2code generator.

Create the module-k8s-dashboard project

mkdir web-ui-dashboard
cd web-ui-dashboard

Let's create a package.json for this module:

• in the particular case the package name is @grucloud/example-module-k8s-web-ui-dashboard
• the entry point should be the generated file resources.js

npm init

Install the dependencies:

npm install @grucloud/core @grucloud/provider-k8s @grucloud/k8s-manifest2code

Npm scripts

We'll add 2 npm scripts in the package.json.

• download-manifest: downloads the manifest locally and name it web-ui-dashboard.yaml.
• gen-code: generate the GruCloud code resource.js from this manifest with k8s-manifest2code.

We found out the manifest URL from the official documentation 'deploying-the-dashboard-ui'

// package.json
  "scripts": {
    "download-manifest": "curl -L -o web-ui-dashboard.yaml https://raw.githubusercontent.com/kubernetes/dashboard/v2.0.0/aio/deploy/recommended.yaml",
    "gen-code": "k8s-manifest2code --input web-ui-dashboard.yaml"
  },

Download the manifest

Download the manifest with:

npm run download-manifest

Check to content of web-ui-dashboard.yaml, you are supposed to find a set of K8s resources such as Namespace, ServiceAccount, Service, Secret, Config Map, Role, RoleBinding, Deployment, etc ....

Generate the code

Generate the GruCloud source code from the k8s manifest:

npm run gen-code

Check the resources.js to find out which resources will be set up.

Create an example project

mkdir example
cd example

Let's create a package.json, in the case the package name is @grucloud/example-module-k8s-web-ui-dashboard:

npm init

Install the dependencies:

npm install @grucloud/core @grucloud/provider-k8s @grucloud/example-module-k8s-web-ui-dashboard

Create the iac.js file

It is now time to create a K8s provider and uses the generated createResources function from package @grucloud/module-k8s-web-ui-dashboard

// iac.js
const { K8sProvider } = require("@grucloud/provider-k8s");
const { createResources } = require("../resources");

exports.createStack = async ({ createProvider }) => {
  const provider = createProvider(K8sProvider, { config: require("./config") });
  const resources = await createResources({ provider });
  return { provider, resources };
};

Deploying

Ensure your cluster is running and execute:

gc apply

┌──────────────────────────────────────────────────────────────────────────────────────────────┐
│ Plan summary for provider k8s                                                                │
├──────────────────────────────────────────────────────────────────────────────────────────────┤
│ DEPLOY RESOURCES                                                                             │
├────────────────────┬─────────────────────────────────────────────────────────────────────────┤
│ ServiceAccount     │ kubernetes-dashboard                                                    │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ Service            │ kubernetes-dashboard, dashboard-metrics-scraper                         │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ Secret             │ kubernetes-dashboard-certs, kubernetes-dashboard-csrf                   │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ ConfigMap          │ kubernetes-dashboard-settings                                           │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ Role               │ kubernetes-dashboard                                                    │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ ClusterRole        │ kubernetes-dashboard                                                    │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ RoleBinding        │ kubernetes-dashboard                                                    │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ ClusterRoleBinding │ kubernetes-dashboard                                                    │
├────────────────────┼─────────────────────────────────────────────────────────────────────────┤
│ Deployment         │ kubernetes-dashboard, dashboard-metrics-scraper                         │
└────────────────────┴─────────────────────────────────────────────────────────────────────────┘
? Are you sure to deploy 12 resources, 9 types on 1 provider? › (y/N)
Deploying resources on 1 provider: k8s
✓ k8s
  ✓ Initialising
  ✓ Deploying
    ✓ ServiceAccount 1/1
    ✓ Service 2/2
    ✓ Secret 2/2
    ✓ ConfigMap 1/1
    ✓ Role 1/1
    ✓ ClusterRole 1/1
    ✓ RoleBinding 1/1
    ✓ ClusterRoleBinding 1/1
    ✓ Deployment 2/2
12 resources deployed of 9 types and 1 provider
Command "gc apply" executed in 52s

The Web Ui Dashboard should be up and running. GruCloud waits for all the resources to up. For instance, a deployment is considered up if one of the container's pod started by the deployment is running.