# Docker images for act

Ubuntu-based images for [nektos/act][nektos/act], kept small while staying compatible with most GitHub Actions.

## Images

Built from [`scripts/act.sh`](./scripts/act.sh). Published to this repo’s Gitea registry:

- **Registry:** `git.keligrubb.com`
- **Image:** `git.keligrubb.com/actions/ubuntu`
- **Tags:** `act-22.04`, `act-24.04`, `act-latest` (and dated tags e.g. `act-24.04-YYYYMMDD`)

## When images are updated

- Dependencies required for actions change
- Changes to GitHub Actions, Act, or the container registry
- Size or performance improvements

## Build locally

You can build and push from this repo without using CI.

**Prereqs:** Docker with `buildx`, and push access to your registry (e.g. `git.keligrubb.com`).

**1. Set env (repo root):**

```sh
export IMAGE_LABEL_OWNER="actions"
export IMAGE_LABEL_REPO="ubuntu"
export SLUG="actions/ubuntu"

export DISTRO="ubuntu"
export TYPE="act"
export RUNNER="root"
export NODE="20 24"
export PLATFORMS="linux/amd64,linux/arm64"

export FROM_IMAGE="buildpack-deps"
export FROM_TAG="24.04"

export TAG="act-24.04"
export LATEST_TAG="act-latest"
export PART_TAG="$(date +%Y%m%d)"
export BUILD_TAG="${TAG}"
export BUILD_TAG_VERSION="${PART_TAG}"
export BUILD_REF="$(git rev-parse HEAD 2>/dev/null || echo unknown)"
```

**2. Log in to your registry:**

```sh
docker login git.keligrubb.com
```

**3. Build and push:**

```sh
tags=""
tags="${tags} git.keligrubb.com/${SLUG}:${TAG}-${PART_TAG}"
tags="${tags} git.keligrubb.com/${SLUG}:${LATEST_TAG}-${PART_TAG}"
tags="${tags} git.keligrubb.com/${SLUG}:${TAG}"
tags="${tags} git.keligrubb.com/${SLUG}:${LATEST_TAG}"

./build.sh --push --tags ${tags}
```

This builds the root `Dockerfile` (which runs `scripts/act.sh`), then pushes to each tag. For a local build only (no push), run `./build.sh`.

**4. Use with act**

Point act at your image, e.g.:

```sh
act -P ubuntu-latest=git.keligrubb.com/actions/ubuntu:act-24.04
```

Or put the image in `.actrc` or your workflow’s `runs-on` image.

## Customising

Edit [`scripts/act.sh`](./scripts/act.sh) to add or remove packages. Keep `DISTRO=ubuntu`, `TYPE=act`, and a valid `RUNNER` user, then re-run the build steps above.

## Licence

Parts of this repository are from [actions/virtual-environments][actions/virtual-environments], used under the [MIT License](https://github.com/actions/virtual-environments/blob/main/LICENSE).

[nektos/act]: https://github.com/nektos/act
[actions/virtual-environments]: https://github.com/actions/virtual-environments