Kubernetes Deployment with Helm

August 26, 2021 - 2 minutes read - 235 words

This post is a quick guide to show how to deploy a containerized application in k8s using helm.

Full code here

Create Sample App

Creating a sample flask application that runs on top of a python base image.

mkdir webapp
cd webapp
python -m venv .env
pip install Flask
pip freeze > requirements.txt

Copy the minimal application from https://flask.palletsprojects.com/en/1.1.x/quickstart/ to app.py

Docker Setup

Create the dockerfile

FROM python:3.8-slim-buster

WORKDIR /app

COPY webapp/requirements.txt requirements.txt
RUN pip3 install -r requirements.txt

COPY webapp/app.py app.py

CMD [ "python3", "-m" , "flask", "run", "--host=0.0.0.0", "--port=80"]

Build the image

docker build -t helmsample:v1 .

Run the container

docker run -d -p 8080:80 helmsample:v1

application should be running at http://localhost:8080

Stop the container

docker stop dockerId

Setting up Helm

helm create deploy

Update few values

 image:
-  repository: nginx
+  repository: helmsample
   pullPolicy: IfNotPresent
   # Overrides the image tag whose default is the chart appVersion.
-  tag: ""
+  tag: "v1"


 ingress:
-  enabled: false
+  enabled: true
   className: ""
-  annotations: {}
-    # kubernetes.io/ingress.class: nginx
-    # kubernetes.io/tls-acme: "true"
+  annotations:
+    kubernetes.io/ingress.class: nginx
+    kubernetes.io/tls-acme: "true"
   hosts:
     - host: chart-example.local
       paths:

Enable Ingress Controller

kubectl apply -f https://raw.githubusercontent.com/kubernetes/ingress-nginx/controller-v0.41.2/deploy/static/provider/cloud/deploy.yaml

Switch to docker-desktop context

kubectl config use-context docker-desktop

Install helm chart

cd  deploy
helm install deploy ./

Fetching localhost with chart-example.local host header will repond with sample app

curl -v http://localhost -H "Host: chart-example.local"

Update the hosts file and you will see the page in browser as well http://chart-example.local/