Creating custom Helm charts in Kubernetes - Try It Yourself

Creating custom Helm charts

📖 Scenario: You are working as a DevOps engineer for a small company. You need to package a simple web application into a Helm chart so it can be easily deployed and managed on Kubernetes clusters.

🎯 Goal: Build a custom Helm chart for a basic web application with configurable image and replica count.

📋 What You'll Learn

Create the Helm chart directory structure with Chart.yaml and values.yaml

Add a configuration variable for the number of replicas

Write the deployment template using Helm template syntax

Output the rendered Kubernetes deployment manifest

💡 Why This Matters

🌍 Real World

Helm charts help package and deploy applications on Kubernetes clusters easily and consistently.

💼 Career

Knowing how to create custom Helm charts is a key skill for DevOps engineers managing Kubernetes deployments.

1

Create Helm chart metadata

Create a file named Chart.yaml with the following content exactly:
apiVersion: v2
name: simple-webapp
version: 0.1.0

Kubernetes

# Create Chart.yaml file with apiVersion, name, and version
# Your code here

Need a hint?

The Chart.yaml file defines the chart's metadata. Use exact keys and values as shown.

2

Add default values configuration

Create a file named values.yaml with these exact entries:
replicaCount: 2
image:
repository: nginx
tag: stable

Kubernetes

apiVersion: v2
name: simple-webapp
version: 0.1.0

# Create values.yaml with replicaCount and image repository and tag
# Your code here

Need a hint?

The values.yaml file holds default settings for your chart. Indentation matters in YAML.

3

Write deployment template using Helm syntax

Create a file named templates/deployment.yaml with a Kubernetes Deployment manifest that uses Helm template syntax to:
- Set replicas to {{ .Values.replicaCount }}
- Set container image to {{ .Values.image.repository }}:{{ .Values.image.tag }}
- Name the deployment {{ .Chart.Name }}

Kubernetes

apiVersion: v2
name: simple-webapp
version: 0.1.0

replicaCount: 2
image:
  repository: nginx
  tag: stable

# Create templates/deployment.yaml with Helm template syntax
# Your code here

Need a hint?

Use double curly braces {{ }} to insert values from values.yaml and chart metadata.

4

Render and output the Helm template

Run the Helm template command to render the deployment manifest and print the output exactly:
helm template simple-webapp .

Kubernetes

apiVersion: v2
name: simple-webapp
version: 0.1.0

replicaCount: 2
image:
  repository: nginx
  tag: stable

---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ .Chart.Name }}
spec:
  replicas: {{ .Values.replicaCount }}
  selector:
    matchLabels:
      app: {{ .Chart.Name }}
  template:
    metadata:
      labels:
        app: {{ .Chart.Name }}
    spec:
      containers:
        - name: {{ .Chart.Name }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          ports:
            - containerPort: 80

# Run the command 'helm template simple-webapp .' in your terminal to see the rendered output
# Your code here

Need a hint?

Use the helm template command in your terminal inside the chart directory to see the rendered Kubernetes manifest.