Deploying Go service with Redis on Kubernetes

👷🏻 Go backend service example explained

This service connects to the Redis once the service is run. There are 2 API endpoints available for you to test if the connection between the service and Redis (which will be deployed as an k8s pod later) works properly. Redis has a configured password as helloworld. This service needs to GET and SET values on Redis with out any errors. You can SET a value through HTTP POST /set?key=<your-key>&value=<your-value> and GET a value HTTP GET /get?key=<your-key>. A key query string won't accept "" (EMPTY STRING). If an internal error occurs, error will be returned in a http response with a status 500 and error message will be provided in a response body.

😂 Some short k8s definition

Kubernetes (k8s) is a kind of cluster that let us deploy pods(an abstraction of containers), services, ect., on it.

Project structures explained

• /app Go backend service source code.
  • The service uses clean architecture design. Try check this out.
• /k8s This one stores k8s object files.
  • redis-development.yaml Redis master pod(container).
  • redis-secret.yaml Redis secret which contains REDIS_PASSWORD (stored in base64 encoded).
  • redis-service.yaml Redis service maps a internal traffic/ip to an Redis master pod. This allows us to access Redis master pod internally (Inside the cluster or Pod-Pod).
  • webapp.yaml Runs our backend services. This is a bad practice. I should split deployment and service in to two files separately.
• Dockerfile Use for building Go backend service image.

You can also get my built image from beamuuuu/redis-getset:latest or

docker pull beamuuuu/redis-getset

• docker-compose.yml Use for running Redis locally on docker container. (Not a k8s deployment!)

Getting Started

You need Minikube and kubectl

1. Create our new Kubernetes cluster

minikube start

2. Apply our k8s secrets, deployments, services, pods, ect., to our cluster. (I'm not gonna explain each yaml files because this is just an k8s setup tutorial)

sh k8s-apply.sh

3. Access the app service by using

minikube service webapp-service --url
// output like http://127.0.0.1:58081 or something.

You should get an URL (above) to your backend service. Then try to GET some keys through your browser. Open your browser and go to <your-url>/get?key=helloredis. Then you should see something like this.

{
    "success":false,
    "message":"redis: nil",
    "payload":null
}

This means our backend works perfectly. The redis: nil in message means on Redis, there is no value for key helloredis which we sent it to the backend.

Now create a HTTP POST to <your-url>/set?key=helloredis&value=welcome. You should get

{
    "success": true,
    "message": "",
    "payload": null
}

This means Redis has set our key-value pair. { "helloredis": "welcome" }

Then go to your browser and enter <your-url>/get?key=helloredis

{
    "success":true,
    "message":"",
    "payload":"welcome"
}

As we can see that right now we have a payload as "welcome". This means once we request for a value of a key "helloredis", Redis returns us a "welcome" which was a value that we have set before.

k8s works fine

If you have finished the Getting Started section, your Kubernetes tutorial is now completed. I recommend anyone who are reading this to learn more about what Kubernetes is, how it works, and some important components inside Kubernetes. I have some FREE useful resources for someone who are getting started on Kubernetes.

• Kubernetes Crash Course for Absolute Beginners [NEW]
• Kubernetes Course - Full Beginners Tutorial (Containerize Your Apps!)
• Learn Kubernetes Basics
• Deploying Redis Cluster on Kubernetes | Tutorial and Examples