Kubernetes became available in Docker for Mac 17.12 CE Edge. Kubernetes in the last year showed that it’s the most flexible and reliable option to run container workloads, all the major cloud providers now offer or are planning to offer a managed Kubernetes service to their customers:
And some great companies that help you deploy and run your own cluster:
After visiting last KubeCon in Austin I have seen a huge increase in the number of companies that specialize in Kubernetes consulting. This list could go on and on :)
In this article we will:
kubectl, the Kubernetes client command. It should be included and configured by the Docker for Mac.
If you are not using Mac or Docker for Mac you can still follow this tutorial step-by-step, just skip the “Enable Kubernetes in your Docker for Mac” section. This tutorial will work for ANY Kubernetes cluster as long as it has an Internet connectivity.
Time to get our hands dirty! Feel free to skip a few things like enabling Kubernetes if you have already done it.
To enable Kubernetes support inside your Docker for Mac, select Enable Kubernetes and click the Apply and restart button:
It should take a bit of time depending on the available Internet bandwidth and once it is done, it should report that the installation is complete. If you have any problems with this step, it might make sense to visit Docker documentation on this matter.
Unlike Minikube, Docker for Mac doesn’t hijack kubectl context, so you have to set it:
Check whether your
kubectl is using the docker-for-desktop context.
Add ingress controller:
Yeah, some of you are probably now like:
But hold on, this command creates RBAC-enabled ingress controller in
webrelay-ingress namespace with already configured credentials for your account. You can read more about Web Relay ingress controller here.
The next step is to write the application. Create a new directory named
hello with the filename
To run the application:
You should be able to see your “Hello World!” message at http://localhost:8080/.
Stop the running Node.js server by pressing Ctrl-C.
The next step is to package your application in a Docker container.
Create a file, also in the
hello directory, named Dockerfile. A Dockerfile describes the image that you want to build. You can build a Docker container image by extending an existing image. The image in this tutorial extends an existing Node.js image.
This Dockerfile starts from the official Node.js image found in the Docker registry, exposes port 8080, copies your server.js file to the image and starts the Node.js server.
Build your Docker image:
What is really nice about Docker for Mac with Kubernetes is that you can easily run locally built Docker images inside Kubernetes cluster. No need to change Docker daemons or push images to the public repositories just to test them out. Now Docker for Mac Kubernetes can run the image you built.
To view Deployments:
Since by default Pod is only accessible by its internal IP address within the Kubernetes cluster, we need to expose it. Create a Service:
To view created services:
Ingresses in Kubernetes provide an easy way to define routing rules between hostnames and services. Let’s get our public endpoint with
relay command client by creating a tunnel:
Parameter –group webrelay-ingress is required to let our ingress controller know which tunnels it can manage.
Note that users with paid plans can specify any custom subdomain (as long as it is not taken) without creating a tunnel first. This allows to just easily define
ingress.yamland ingress controller wil create a tunnel for it.
We are only interested in this
pis9izc72c1wd9i21gxqxm.webrelay.io (host) part. Every user gets a unique link to their tunnel. Edit this code with your tunnel hostname and save it in a folder named
hello with the filename
Your application is now exposed to the public Internet. See next section how to access or just enter that hostname into your browser.
To view existing ingresses:
Backends column should show
<namespace>/<service>/<port> of the exposed service. You can access http://pis9izc72c1wd9i21gxqxm.webrelay.io with your browser (just change the link to your own tunnel address).
You can also use web UI at https://my.webhookrelay.com/tunnels to view your ingresses:
In this article we created, deployed and exposed an app to the Internet that is running locally on our laptops. Some people say that this is an “actual hello world” application and not just the usual “hello localhost”.
With Docker for Mac Kubernetes support it’s now a lot easier to develop and test our applications. Build locally, run locally and demo locally. I hope Web Relay ingress controller will serve you great in developing, testing and running your apps.
As always, if you have any questions, feel free to contact me.