⚠️  This repo contains the source for a component of the Brigade v1.x ecosystem. Brigade v1.x reached end-of-life on June 1, 2022 and as a result, this component is no longer maintained.

BUCK: Brigade Universal Controller for Kubernetes

BUCK is the fastest way to build new controllers for Kubernetes. Define your CRD (or use an existing resource), and write a few lines of JavaScript for your controller code.

BUCK uses the event system of Brigade to handle Kubernetes events. And it abstracts away the process of modeling and defining resource types. Its ultra-fast Rust server manages the controller (the informer in Kubernetes terminology) and you just write the handling code. If you can install a Helm chart and write a few lines of JS, you can build a Kubernetes controller.

If you have Brigade installed and configured, BUCK is as easy as 1-2-3.

Step 0. Clone this repository

You know what to do! git clone git@github.com:brigadecore/buck.git

Step 1: Write your JS Controller

This is a brigade.js-flavored script:

const { events } = require("brigadier");

events.on("resource_added", handle);     // New resource is created
events.on("resource_modified", handle);  // Existing resource is modified
events.on("resource_deleted", handle);   // Existing resource is deleted
events.on("resource_error", handle);     // Something weird happened, and we think you should know about it

function handle(e, p) {
    let obj = JSON.parse(e.payload); // <-- your Kubernetes object
    console.log(obj);
}

Step 2: Create a new Brigade project

Creating new Brigade projects is done with brig project create. You can tune your project however you want, but this is the most minimal way:

• Choose no-VCS
• Name it (e.g. buck-test)
• Answer No for Add Secrets
• Hit enter for Auto-generate Generic Gateway secret
• Leave Default script ConfigMap name blank
• Type brigade.js when prompted to Upload a default brigade.js script (This is the path to the brigade.js script you created in Step 1)
• Answer N for Configure advanced options

This will give you a brigade ID that looks something like brigade-XXXXXXXXXXXXXX. You will need this.

Step 3. Use Helm to Define Your Resource

Your Helm values.yaml file is your entry point. Create the file and add your data:

project: brigade-XXXXXXXXXXXXXX  # The ID created from Step 2
crd: # The CRD that you want to define.
    group: my.example.com
    version: v1
    kind: Book   # This should be capitalized
    plural: books

You can get the Brigade project ID by running brig project list.

Now you can install the Helm 3 chart with helm install $NAME ./charts/buck -f values.yaml, where $NAME is whatever name you want (usually something like book-controller).

Technical Details

The BUCK Helm chart does the following things:

• Creates a CRD (if necessary)
• Creates a Brigade project
• Adds a one-shot controller for your resource type
• Configures the controller to execute for your project

All you need to do is install the chart.