In a world where different communities cluster environments using one command, the deployment process can be much easier with the use of Helm charts. Helm is a package manager and templating engine for Kubernetes, which allows for easier deployment and management of applications. In this blog post, we will take a closer look at the structure of a Helm chart to gain a better understanding of how it works.
The Directory Structure of a Helm Chart
A Helm chart is typically made up of a directory structure that includes the following components:
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Chart.yaml: This file contains all the meta information about the chart, such as its name, version, list of dependencies, and other details.
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values.yaml: This is the place where all the values are configured for the template files. These values will be the default values that can be overridden later.
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Charts: This directory contains the chart dependencies. If this chart depends on other charts, those dependencies will be stored here.
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Templates: This is where the template files are stored. When you execute the
helm installcommand to deploy the files into Kubernetes, the template files from here will be filled with the values from thevalues.yamlfile. This produces valid Kubernetes manifests that can then be deployed into Kubernetes. -
Other Files: Optionally, you can also include other files in this folder, such as a readme or license file.
Use Cases for Helm
Helm can be practical when using continuous delivery and continuous integration for applications. In your built pipeline, you can use Helm to template the YAML files and replace the values on the fly before deploying them. This allows for faster and more efficient deployment of applications.
Another use case for Helm is when you need to deploy the same set of applications across different Kubernetes clusters. Instead of deploying the individual YAML files separately in each cluster, you can package them up to make your own application chart. This chart will have all the necessary YAML files that the deployment needs, and can be used to redeploy the same application in multiple clusters.
Conclusion
Understanding the structure of a Helm chart can be beneficial for managing and deploying applications in Kubernetes. With its package manager and templating engine, Helm can streamline the deployment process and make it easier to manage and deploy applications. Whether you are using continuous delivery, continuous integration, or deploying applications across multiple clusters, Helm can be a useful tool for your deployment needs.
