Helmule

This tool is not production ready yet, I'm still changing the config format, so don't rely on it for a time being.

What it's supposed to do?

It would be just a yet another tool to mirror helm charts, but there is a couple of features that (I hope) are making this tool special. So let's go through all of them.

So, let's imaging you need to mirror a helm chart for whatever reason. Maybe you just don't trust original authors that much, or you use ArgoCD that doesn't know what is helm and how it's supposed to be used, or whatever else. We'll start by a simple mirroring and then walk through all features later.

First we create a config file

repositories: {}
charts: {}
mirrors: {}

Currently there are two types of mirrors that are supported:

• Git
• Custom Comand

Let's start with git.

# Basic example
mirrors:
  - name: my-git-mirror
    git:
      url: git@git.badhouseplants.net:allanger/helmuled-charts.git
      branch: mirror-something
      path: charts/something
      commit: |-
        chore: mirror something
                

As you can see, it won't work on scale, so all the field can be templated using the chart data and a couple of helpers.

  - name: badhouseplants-git
    git:
      url: git@git.badhouseplants.net:allanger/helmuled-charts.git
      branch: upgrade-{{ name }}-to-{{ version }}
      path: charts/{{ name }}
      commit: |-
        chore: mirror {{ name }}-{{ version }}

        upstream_repo: {{ repo_url }}        

It can be scaled better already. URL can also be templated, and there is special property for variables, that you can also use here

variables:
  git-msg: Hello there

mirrors:
  - name: badhouseplants-git
    git:
      url: git@git.badhouseplants.net:allanger/helmuled-charts.git
      branch: upgrade-{{ name }}-to-{{ version }}
      path: charts/{{ name }}
      commit: |-
        chore: mirror {{ name }}-{{ version }}
        {{ vars.git-msg }}
        upstream_repo: {{ repo_url }}        

Currently, there are two available helpers:

• date: {{ date }}
• time: {{ time }}

Also you can provide rebase<bool> and default_branch<string>, if you want helmiule to rebase before pushing.

That would be it for git, and now the second option: CustomCommand

The process of mirroring is split into two parts:

• Package
• Upload

The second is being executed only if you don't run in the dry-run mode. Git mirror handles it in code. But for custom command you'll have to define it yourself. Just check the following example:

mirrors:
  - name: custom-command
    custom_command:
      package:
        - zip -r {{ name }}-{{ version }}.zip {{ name }}-{{ version }}
      upload:
        - rm -f /tmp/{{ name }}-{{ version }}.zip
        - rm -rf /tmp/{{ name }}-{{ version }}
        - cp {{ name }}-{{ version }}.zip /tmp
        - unzip /tmp/{{ name }}-{{ version }}.zip -d /tmp/{{ name }}-{{ version}}

These command are executed from the workdir. It's created during the run, and by default it's using a library to create a temporary directory, but you also can chose one by providing the -w/--workdir flag. Run will fail if this folder exists though, because it's expected to be created by helmule.

Now, when we got our mirrors, we need to start mirroring.

...to be continued...