Pull request testing is done by running Helm's Chart Testing automatically, which lints the chart and installs it in a cluster created using Kubernetes in Docker (KIND).
The Helm's Chart Testing action runs ct lint-and-install. This is the main logic for validating pull requests. Only charts that have changed are tested.
Testing logic has been extracted from the chart-testing project, a Go library that provides utilities to lint, install, and test charts. Its Docker image can be run by anyone on their own charts.
Testing charts with default values may not always be suitable. For example, some charts may require values that are not part of the chart's default values.yaml (such as keys). Furthermore, it is often desirable to test a chart with different configurations, reflecting different use cases (for example, setting a password instead of using the default generated one, activating persistence instead of using the default emptyDir volume, etc.).
To enable custom test values, create a directory named ci in the chart's directory and add any number of *-values.yaml files to it Only files with the suffix -values.yaml are considered. Instead of using defaults, the chart is installed and tested separately for each files using --values.
For examples, take a look at the existing tests in this repository.
To use default test values, an empty
valuesfile must be present in thecidirectory.