Exploring Helm Template Dictionary Objects: Syntax Evolution and Best Practices

#kubernetes #go #tpl #tooling

Helm, the Kubernetes package manager, offers a robust templating system to streamline the deployment of applications. One powerful feature within Helm charts is the ability to define and manipulate dictionary objects using its templating language. In this blog post, we'll delve into the usage of Helm template dictionary objects, examining the evolution of syntax for storing properties and highlighting best practices.

Introduction to Helm Template Dictionary Objects

Template File viewed with Word Wrap on

Template File viewed with Word Wrap off

This syntax allowed for creating a dictionary ($globDict) containing multiple properties and their corresponding values. The problem with the above syntax is that it is too difficult to add/update/delete entries where we have a large set of properties as it stores them in a single line.

Syntax Evolution: Refining Dictionary Property Addition

As Helm evolved, a more concise and efficient syntax for adding properties to an existing dictionary emerged. Instead of creating the entire dictionary in a single line, the set function became the preferred method for appending properties to an existing dictionary.

The evolution looks like this:

This refined approach allows for the incremental addition of properties to the $globDict dictionary. Each subsequent set function appends a new key-value pair without recreating the entire dictionary, improving code readability and maintainability.

Best Practices and Considerations

Incremental Addition

Embrace the incremental addition of properties to dictionaries using the set function. This practice enhances code clarity and reduces redundancy.

Avoiding Reassignment

Minimize reassignment of variables like $globDict to maintain consistency and prevent unintentional overrides or data loss.

Consistent Naming Conventions

Adopt consistent naming conventions for keys within dictionaries to facilitate readability and maintainability across the Helm charts.

Testing and Validation

Validate Helm templates by rendering them and conducting thorough testing to ensure that the generated Kubernetes manifests reflect the expected configurations.

Conclusion:
Helm template dictionary objects offer a flexible and powerful way to manage properties within Kubernetes deployments. By understanding the evolution of syntax and following best practices, developers can create cleaner, more maintainable Helm charts. For more information on this, you can visit here.