Getting started

This document describes how to setup your development environment.

Preparation

Make sure the following software is installed and added to the $PATH variable:

Clone the repository into $GOPATH/src/github.com/kubernetes/dashboard and install the dependencies:

  1. npm ci

If you are running commands with root privileges set --unsafe-perm flag:

  1. npm ci --unsafe-perm

Running the cluster

To make Dashboard work you need to have cluster running. If you would like to use local cluster we recommend kubeadm, minikube or kubeadm-dind-cluster. The most convenient way is to make it work is to create a proxy. Run the following command:

  1. kubectl proxy

kubectl will handle authentication with Kubernetes and create an API proxy with the address localhost:8080. Therefore, no changes in the configuration are required.

Serving Dashboard for Development

Quick updated version:

  1. npm start

Another way to connect to real cluster while developing dashboard is to specify options for npm like following:

  1. npm run start:https --kubernetes-dashboard:kubeconfig=<path to your kubeconfig>

Please see here which options you can specify to run dashboard with npm.

Open a browser and access the UI under localhost:8080.

In the background, npm start makes a concurrently call to start the golang backend server and the angular development server.

Once the angular server starts, it takes some time to pre-compile all assets before serving them. By default, the angular development server watches for file changes and will update accordingly.

As stated in the Angular documentation, i18n does not work in the development mode. Follow Building Dashboard for Production section to test this feature.

Due to the deployment complexities of i18n and the need to minimize rebuild time, the development server only supports localizing a single locale at a time. Setting the “localize” option to true will cause an error when using ng serve if more than one locale is defined. Setting the option to a specific locale, such as “localize”: [“fr”], can work if you want to develop against a specific locale (such as fr).

Building Dashboard for Production

To build dashboard for production, you still need to install bc.

The Dashboard project can be built for production by using the following task:

  1. npm run build

The code is compiled, compressed, i18n support is enabled and debug support removed. The dashboard binary can be found in the dist folder.

To build and immediately serve Dashboard from the dist folder, use the following task:

  1. npm run start:prod

Open a browser and access the UI under localhost:9090. The following processes should be running (respective ports are given in parentheses):

Dashboard backend (9090) ---> Kubernetes API server (8080)

To build the docker image on darwin OS you will need to set environment variable for go to build as linux:

  1. export GOOS=linux

In order to package everything into a ready-to-run Docker image, use the following task:

  1. npm run docker:build:head

You might notice that the Docker image is very small and requires only a few MB. Only Dashboard assets are added to a scratch image. This is possible, because the dashboard binary has no external dependencies. Awesome!

Run the tests

Unit tests should be executed after every source code change. The following task makes this a breeze. The full test suite includes unit tests and integration tests.

  1. npm run test

You can also run individual tests on their own (such as the backend or frontend tests) by doing the following:

  1. npm run test:frontend

or

  1. npm run test:backend

The code style check suite includes format checks can be executed with:

  1. npm run check

The code formatting can be executed with:

  1. npm run fix

These check and formatting involves in go, ts, scss, html, license and i18n files.

Committing changes to your fork

Before committing any changes, please run npm run check. This will keep you from accidentally committing non tested and unformatted code.

Since the hooks for commit has been set with husky into <dashboard_home>/.git/hooks/pre-commit already if you installed dashboard according to above, so it will run npm run fix and keep your code as formatted.

Then you can commit your changes and push them to your fork:

  1. git commit
  2. git push -f origin my-feature

Easy way to build your development environment with Docker

At first, change directory to kubernetes dashboard repository of your fork.

Allow accessing dashboard from outside the container

Development container runs Kubernetes Dashboard in insecure mode by default, but Kubernetes Dashboard is not exposed to outside the container in insecure mode by default.

To allow accessing dashboard from outside the development container, pass value for --insecure-bind-address option to dashboard as follows:

  • Set K8S_DASHBOARD_BIND_ADDRESS environment variable as "0.0.0.0" before using aio/develop/run-npm-on-container.sh.
  • Run like npm run [command] --kubernetes-dashboard:bind_address="0.0.0.0", when you run dashboard from inside the container.

Change port number for dashboard

As default, development container uses 8080 port to expose dashboard. If you need to change the port number, set K8S_DASHBOARD_PORT environment variable before using aio/develop/run-npm-on-container.sh. The variable would be passed to --port option for docker and npm run start command inside container, then container exports the port and dashboard starts at the port.

To run dashboard using Docker at ease

  1. Run aio/develop/run-npm-on-container.sh.

That’s all. It will build dashboard container from your local repository, will create also kubernetes cluster container for your dashboard using kind, and will run dashboard. Then you can see dashboard http://localhost:8080 with your browser.

To run with your another Kubernetes cluster

  1. Copy kubeconfig from your cluster, and confirm the URL for API server in it, and modify it if necessary.
  2. Set filepath for kubeconfig into K8S_DASHBOARD_KUBECONFIG environment variable.
  3. If you deployed dashboard-metrics-scraper in your cluster, set its endpoint to K8S_DASHBOARD_SIDECAR_HOST environment variable.
  4. Change directory into your dashboard source directory.
  5. Run aio/develop/run-npm-on-container.sh.

These manipulations will build container, and run dashboard as default.

To run npm commands as you want

Also, you can run npm commands described in package.json as you want

e.g.

  1. To test dashboard, run aio/develop/run-npm-on-container.sh run test.
  2. To check your code changes, run aio/develop/run-npm-on-container.sh run check.

This container create user with UID and GID same as local user, switch user to user with gosu and run commands. So created or updated files like results of npm run fix or npm run build would have same ownership as your host. You can commit them immediately from your host.

To run container without creating cluster and running dashboard

  1. Set K8S_DASHBOARD_CMD environment variable as bash.
  2. Run aio/develop/run-npm-on-container.sh.
  3. Run commands as you like in the container.

This runs container with bash command.

To access console inside of running development container

  1. Run docker exec -it k8s-dashboard-dev gosu user bash.

Copyright 2019 The Kubernetes Dashboard Authors