Docker Configuration for chainguard-dev/apko

This documentation provides a step-by-step guide on how Docker is utilized within the development environment for the chainguard-dev/apko project. It focuses on the relevant Makefile targets and the interplay between Go and Docker within the setup.

Prerequisites

Ensure that Docker is installed and running on your development machine. You should also have a basic understanding of Makefiles, Go programming, and Docker concepts.

Using Docker in the Development Environment

Docker is a critical component in the development workflow for chainguard-dev/apko. It is primarily used for packaging and distributing images during development. Below are detailed steps and code examples illustrating how to effectively use Docker as part of your development process.

Makefile Targets

The Makefile associated with the project contains various targets that leverage Docker for building and signing images.

Build and Sign Images

The sign-image target is essential for creating and verifying images. To sign an image, use the following command:
```
make sign-image
```
This command will execute the signing process as defined in the Makefile.
Local Image Creation

The ko-local target utilizes ko, which is a tool for building images specifically for Kubernetes.

To build an image using this target, run:
```
make ko-local
```
This will initiate a build process that uses local Docker to create the images as specified in your configuration.
Interacting with Docker through Makefile

The Makefile provides several capabilities for interacting with Docker. An example to perform a complete workflow can be outlined as follows:
```
make clean          # Clean previous builds
make golangci-lint  # Run linting
make test           # Execute tests
make ko-local       # Build the image
make sign-image     # Sign the image
```
Each of these targets plays a role in ensuring that the code is properly packaged and verified through Docker.

Example of Dockerized Build with Go

Within the chainguard.dev/apko module, Docker is utilized in conjunction with Go to ensure an efficient build process. The following example demonstrates a typical Docker build configuration within a Makefile.

.PHONY: build
build:
    docker build -t my-apko-image .

This command runs a Docker build using the Dockerfile located in the current directory and tags the resulting image as my-apko-image.

Generating and Applying Konfigurations

The generate and ko-apply targets allow users to generate Kubernetes configurations and apply them using Docker facilities. Use the below commands in sequence:

make generate       # Generate configurations
make ko-apply       # Apply generated configurations

Cleaning Up Docker Resources

To remove unnecessary Docker images, containers, or volumes that were created during the build and testing phases, the clean target can be run:

make clean

Ensure to review the Makefile for any specific Docker cleanup commands, which may be tailored to your local environment.

Troubleshooting and Logs

For troubleshooting, the logs can be viewed with the corresponding Makefile target. For example:

make log-%

Replace % with the specific log you wish to view to assist in debugging any issues related to Docker runs.

Conclusion

The Docker configuration within the chainguard-dev/apko development environment plays an integral role in building, signing, and managing images effectively. By leveraging the provided Makefile targets, developers can harness Docker’s capabilities to streamline their development workflows, ensure consistency, and enhance collaboration.

This documentation reflects the workings of Docker in the context of development and is built upon the available Makefile functionalities. For a more detailed exploration, direct reference to the project documentation and the Makefile itself may be beneficial.