Container Build & Publish Action

A reusable GitHub Actions workflow for building and publishing Docker container images to GitHub Container Registry (GHCR).

Features

• Builds and publishes Docker images to ghcr.io/netwarlan
• Automatic tagging based on branch (main → latest, others → branch name)
• Multi-platform build support (amd64, arm64, etc.)
• GitHub Actions cache for faster builds
• OCI image labels for traceability (git sha, repo URL, etc.)
• Concurrency control to prevent duplicate builds
• Dependabot configured for automatic action updates

Usage

Basic Usage

name: Build Container

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

jobs:
  build:
    uses: netwarlan/action-container-build/.github/workflows/build-publish.yaml@main
    with:
      image-name: my-application

Advanced Usage

jobs:
  build:
    uses: netwarlan/action-container-build/.github/workflows/build-publish.yaml@main
    with:
      image-name: my-application
      dockerfile: ./docker/Dockerfile.prod
      context: ./docker
      platforms: linux/amd64,linux/arm64

Using Outputs

jobs:
  build:
    uses: netwarlan/action-container-build/.github/workflows/build-publish.yaml@main
    with:
      image-name: my-application

  deploy:
    needs: build
    runs-on: ubuntu-latest
    steps:
      - name: Deploy image
        run: |
          echo "Deploying ${{ needs.build.outputs.image }}@${{ needs.build.outputs.digest }}"

Inputs

Input	Description	Required	Default
image-name	Name of the image to build and deploy	Yes	-
dockerfile	Path to Dockerfile	No	./Dockerfile
context	Build context path	No	.
platforms	Target platforms (comma-separated)	No	linux/amd64
version	Semantic version tag to apply to the image (e.g., v1.2.3)	No	''
build-args	Newline-separated list of build-time variables	No	''
push	Whether to push the image to the registry	No	true

Outputs

Output	Description
digest	Image digest (sha256)
image	Full image reference (without tag)

Image Tags

Images are automatically tagged based on the branch:

Branch	Tags
main	latest, <branch>, <sha>
Other	<branch>, <sha>

When version is provided, the version tag (e.g., v1.2.3) is also applied.

Requirements

The calling repository must have:

• A Dockerfile (or specify path via dockerfile input)
• Write access to the ghcr.io/netwarlan registry (automatic for repos in the netwarlan org)

License

MIT