Docker action

This action builds Rust code, builds a thin Docker container with the resulting executable, then saves the image as <output-file-name>.tar.zip.

Inputs

• app-name: App name (from Cargo.toml)
• output-file-name: Name of the output file (without extension)

Refer to action.yaml for details.

The action assumes the presence of Cargo.toml, Cargo.lock and a src folder contains Rust code.

Outputs

• output_file_path: output file path

Refer to action.yaml for details.

Example usage

steps:
  - uses: john-cd/rust_github_action@v1

An example workflow is found in ./test_workflow/.

Testing the Docker image locally

The Dockerfile is a multi-stage build.

To build the "build" Docker image, which contains the Rust tooling, use the following from the root directory:

docker build --tag test_app --target build \
  --build-arg RUST_VERSION=1.75 --build-arg APP_NAME=test_app \
  --platform linux/amd64 --file ./Dockerfile   ./test_app

Substitute --target final to build the "final" stage, which only contains the final executable.

Run the Docker image and exec into it to inspect it.

docker run -d --name test_container test_app
docker exec -it test_container ash

# or simply
docker run -it --name test_container test_app ash

Create a new version of the GitHub Action

Create a tag, push it to the remote origin. The tag will be used by GitHub Action as the Action version. Then update the version in your workflows e.g. john-cd/rust_github_action@v2

# List existing tags
git tag
# Create local tag
git tag -a -m "Description of this release" v2
git tag
# Show details about the tag
git show v2
# Push tag to remote
git push origin v2
# git push --follow-tags

Git Basics - Tagging

Docker Compose config

Docker Compose configuration is also provided, but it is not used by the GitHub Action itself.

compose.yaml uses the build stage.

To build the Docker image using Compose, use

docker compose build

To test the build stage with the provided test_app, use

docker compose -f compose.yaml -f compose-test.yaml build

To build and run the final Docker image using Compose, use compose-final.yaml:

docker compose -f compose.yaml -f compose-final.yaml build
docker compose -f compose.yaml -f compose-final.yaml up -d

# or simply
docker compose -f compose.yaml -f compose-final.yaml up -d --build

To test the final stage with the provided test_app, use

docker compose -f compose.yaml -f compose-final.yaml -f compose-test.yaml up -d --build

References

• Creating a composite action
• Creating a Docker container action
• Docker's Rust guide