helmgap

Helmgap allows you to deploy a Helm Chart into airgap environments by generating a container image registry archive for a given chart. Under the hood it wraps a combination of Helm and kbld (k14s) to firstly generate the manifest with images and then derive the chart images.

The end product is a tar file containing all the images required by the chart which can be read using docker load registry.tar or crd import registry.tar

Requirements

You will need

• helm (brew install helm)
• kbld (brew tap k14s/tap && brew install kbld)
• Java 9+
• Linux

Usage

1. Add the helmgap dependency to your maven pom.xml

<dependency>
    <groupId>uk.co.solong</groupId>
    <artifactId>helmgap</artifactId>
    <version>1.7</version>
</dependency>

2. Call the library

ChartDescriptor chartDescriptor = ChartDescriptor.byShortName("bitnami", "redis", "6.0.0");
HelmGap helmgap = new HelmGap();
AirgapInstall result = helmgap.buildAirgap(chartDescriptor);
File imageArchive = result.getAirgapInstallerArchive(); //the airgap registry you requested.
File lockFile = result.getLockFile(); //the associated lockfile requried for loading.

The above imageArchive file is

• redis-airgap-6.0.0.tgz - the container images required by the helm chart, in KBLD image format.

You can also get a copy of the helm chart (useful!).

File chart = files.getOriginalChart(); //the original chart

The above chart file is

• redis-6.0.0.tgz - the original helm chart.

That's it!

Advanced Usage

There are 3 different chart descriptors supported which cover all valid helm pull syntax:

• Short Name (can be used when the repository already exists on the machine via helm repo add)

ChartDescriptor chartDescriptor = ChartDescriptor.byShortName("stable", "hackmd", "0.1.0");

• Repo URL (can be used when the repo url is known, but the repo has not necessarily been added to the machine)

ChartDescriptor chartDescriptor = ChartDescriptor.byRepoUrl("https://charts.bitnami.com/bitnami", "hackmd", "0.1.0");

• Chart URL (use if only the chart url is known)

ChartDescriptor chartDescriptor = ChartDescriptor.byChartUrl("http://storage.googleapis.com/kubernetes-charts/dask-1.1.0.tgz");

Specifying helm and kbld

new HelmGap("/path/to/helm", "/path/to/kbld")