helm-create-tag-from-version-action

This simple Github Action is designed to help you automatically create tags from your Helm Chart. You would run this action after you have updated your Helm Chart version (and committed the change) - and this chart would then create a tag named {{ .Chart.Name }}-{{ .Chart.Version }} for you.

Basic Flow

The idea behind the workflow below is that there is both "application code" and "chart code" in your repository - and these are fundamentally separate but related. A developer will usually iterate rapidly on the application code, while iterating less frequently on the chart code.

Because your Helm Chart is supposed to point at a specific (and already existing) Docker Image tag, it is not easy to coordinate one git tag that has both the updated chart values AND has already built/published the Docker image. Instead, we treat these two different sets of artifacts as independent releases from within the same repository.

The developer is responsible for iterating on their application code, and creating the tag that triggers the build/publishing of their release artifact (the application Docker image). From there, the CI system automatically updates the Helm chart values, revs its version, and then publishes a new tag and Github Release.

1. Developer pushes their application code continually to HEAD
2. Developer tags an application release v1.2.3
3. CI system builds Docker artifact myapp:v1.2.3 (hint: see Nextdoor/docker-image-retag-action)
4. CI system updates chart/values.yaml and chart/Chart.yaml setting the Chart version to 0.1.52. (hint: see Nextdoor/helm-set-image-tag-action)
5. This action then generates a new Github Tag pointing to myapp-chart-0.1.52 and also moves the production tag to the same commit.

Features

Release Cutting

By default, this action will also create a matching Github Release for your tag. This requires that you set the GITHUB_TOKEN environment variable and provide that token with the right privileges.

Tag Moving

In addition to creating a new git tag, this action can also move an existing tag to point to the current tag that was just created. This is useful if you have a regular tag that you point developers or applications at (say stable or production) and you want to move that tag along with your releases.

Usage

# .github/workflows/release.yml
name: Release
on:
  push:
    branches:
      - '!*'
    tags:
      - v*
jobs:
  release:
    runs-on: ubuntu-latest
    steps:
    - uses: actions/checkout@master
      with:
        fetch-depth: '0'

    # ... insert your code here that handles automatically updating your Helm
    # Chart version and values... or use something like our
    # helm-set-image-tag-action.
    - name: Update Helm Chart Values
      uses: Nextdoor/helm-set-image-tag-action@main
      with:
        verbose: true
        tag: ${{ github.ref }}
        values: charts/app/values.yaml
        keys: .image.tag
        bump_level: patch
        commit_branch: main

    - name: Create Chart Release Tag
      uses: Nextdoor/helm-create-tag-from-version-action@main
      env:
        GITHUB_TOKEN: ${{ github.token }}
      with:
        verbose: true
        chart_dir: charts/app
        create_release: true