Introduction

Helm, the package manager for Kubernetes, offers the helm template command to render Helm charts into Kubernetes YAML manifests. This command is useful for generating and inspecting the Kubernetes resources that would be deployed using Helm charts. In this article, we'll explore the helm template command, its purpose, and how to use it effectively, accompanied by a practical example.

Understanding helm template Command: The helm template the command is used to render Helm charts into Kubernetes YAML manifests. It processes the templates in the Helm chart and substitutes the values to generate Kubernetes resource definitions. This allows users to preview the resources that would be deployed without actually installing them.

Rendering Kubernetes Manifests: Let's explore how to use the helm template command to render Helm charts into Kubernetes YAML manifests.

Example:

$ helm template my-chart/

Output:

---
# Source: my-chart/templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-chart
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: my-chart
    spec:
      containers:
      - name: my-chart
        image: nginx:1.21.5
        ports:
        - containerPort: 80
---
# Source: my-chart/templates/service.yaml
apiVersion: v1
kind: Service
metadata:
  name: my-chart
spec:
  ports:
  - port: 80
    targetPort: 80
  selector:
    app: my-chart

Interpreting the Output:

The output displays the rendered Kubernetes YAML manifests generated from the Helm chart my-chart.
Each YAML document represents a Kubernetes resource, including Deployments and Services, with substituted values.

Using Rendered Kubernetes Manifests: Once rendered, users can inspect the generated Kubernetes YAML manifests to ensure they match the expected configurations before deploying them to a Kubernetes cluster.

Conclusion

The helm template command is a valuable tool for generating Kubernetes YAML manifests from Helm charts. By using this command, users can preview the resources that would be deployed without actually installing them, facilitating validation and customization of Kubernetes configurations.

An Overview of helm template Command

Introduction

Conclusion