ct is the the tool for testing Helm charts.
It is meant to be used for linting and testing pull requests.
It automatically detects charts changed against the target branch.
It is recommended to use the provided Docker image which can be found on Quay. It comes with all necessary tools installed.
Download the release distribution for your OS from the Releases page:
ct binary, add it to your PATH, and you are good to go!
A Docker image is available at
quay.io/helmpack/chart-testing with list of
available tags here.
$ brew install chart-testing
See documentation for individual commands:
For a more extensive how-to guide, please see:
ct is a command-line application.
All command-line flags can also be set via environment variables or config file.
Environment variables must be prefixed with
Underscores must be used instead of hyphens.
CLI flags, environment variables, and a config file can be mixed. The following order of precedence applies:
- CLI flags
- Environment variables
- Config file
Note that linting requires config file for yamllint and yamale.
If not specified, these files are search in the current directory, the
.ct directory in current directory,
/etc/ct, in that order.
Samples are provided in the etc folder.
The following example show various way of configuring the same thing:
With remote repo:
ct install --remote upstream --chart-dirs stable,incubator --build-id pr-42
If you have a chart in current directory and ct installed on the host then you can run:
ct install --chart-dirs . --charts .
With docker it works with:
docker run -it --network host --workdir=/data --volume ~/.kube/config:/root/.kube/config:ro --volume $(pwd):/data quay.io/helmpack/chart-testing:v3.7.1 ct install --chart-dirs . --charts .
workdir param is important and must be the same as volume mounted.
export CT_REMOTE=upstream export CT_CHART_DIRS=stable,incubator export CT_BUILD_ID ct install
remote: upstream chart-dirs: - stable - incubator build-id: pr-42
ct install --config config.yaml
ct supports any format Viper can read, i. e. JSON, TOML, YAML, HCL, and Java properties files.
Notice that if no config file is specified, then
ct.yaml (or any of the supported formats) is loaded from the current directory,
/etc/ct, in that order, if found.
Using private chart repositories
When adding chart-repos you can specify additional arguments for the
helm repo add command using
helm-repo-extra-args on a per-repo basis.
This could for example be used to authenticate a private chart repository.
chart-repos: - incubator=https://incubator.io - basic-auth=https://private.com - ssl-repo=https://self-signed.ca helm-repo-extra-args: - ssl-repo=--ca-file ./my-ca.crt
ct install --config config.yaml --helm-repo-extra-args "basic-auth=--username user --password secret"
Building from Source
ct is built using Go 1.13 or higher.
build.sh is used to build and release the tool.
It uses Goreleaser under the covers.
Note: on MacOS you will need
GNU Coreutils readlink.
You can install it with:
brew install coreutils
gnubin to your
echo 'export PATH="$(brew --prefix coreutils)/libexec/gnubin:$PATH"' >> ~/.bash_profile bash --login
To use the build script:
$ ./build.sh -h Usage: build.sh <options> Build ct using Goreleaser. -h, --help Display help -d, --debug Display verbose output and run Goreleaser with --debug -r, --release Create a release using Goreleaser. This includes the creation of a GitHub release and building and pushing the Docker image. If this flag is not specified, Goreleaser is run with --snapshot
Before a release is created, versions have to be updated in the examples. A pull request needs to be created for this, which should be merged right before the release is cut. Here's a previous one for reference: https://github.com/helm/chart-testing/pull/89
The release workflow is dispatched from github actions
Versions must start with a lower-case
v, e. g.
The previous MAJOR version will be supported for three months after each new MAJOR release.
Within this support window, pull requests for the previous MAJOR version should be made against the previous release branch.
For example, if the current MAJOR version is
v2, the pull request base branch should be
When upgrading from
< v2.0.0 you will also need to change the usage in your scripts.
This is because, while the v2.0.0 release has parity with
v1, it was refactored from a bash library to Go so there are minor syntax differences.
Compare v1 usage with this (
v2) version's README usage section above.