Example Containerized Go Development Environment

This repository contains an example Go project with a containerized development environment. The example project is a simple CLI tool that echos back its inputs.

Why should I containerize my development environment?

There are several advantages to containerizing your development environment:

• You make explicit the tools and versions of tools required to develop your project
• Your builds will be more deterministic and reproducible

These will both make it easier for people to collaborate on your project, as everyone will have the same environment, and make it easier to debug things like CI failures.

Prerequisites

The only requirements to build and use this project are Docker and make. The latter can easily be substituted with your scripting tool of choice.

You will also need to enable the BuildKit builder in the Docker CLI. This can be done by setting DOCKER_BUILDKIT=1 in your environment.

macOS

• Install Docker Desktop
• Ensure that you have make (included with Xcode)
• Run export DOCKER_BUILDKIT=1 in your terminal or add to your shell initialization scripts

Windows

• Install Docker Desktop
• Ensure that you have make
• If using PowerShell, run $env:DOCKER_BUILDKIT=1
• If using command prompt, run set DOCKER_BUILDKIT=1

Linux

• Install Docker
• Ensure that you have make
• Run export DOCKER_BUILDKIT=1 in your terminal or add to your shell initialization scripts

Getting started

Building the project will output a static binary in the bin/ folder. The default platform is for macOS but this can be changed using the PLATFORM variable:

$ make                        # build for your host OS
$ make PLATFORM=darwin/amd64  # build for macOS
$ make PLATFORM=windows/amd64 # build for Windows x86_64
$ make PLATFORM=linux/amd64   # build for Linux x86_64
$ make PLATFORM=linux/arm     # build for Linux ARM

You can then run the binary, which is a simple echo binary, as follows:

$ ./bin/example hello world!
hello world!

To run the unit tests run:

$ make unit-test

To run the linter:

$ make lint

There's then a helpful test alias for running both the linter and the unit tests:

$ make test

Structure of project

Dockerfile

The Dockerfile codifies all the tools needed for the project and the commands that need to be run for building and testing it.

Makefile

The Makefile is purely used to script the required docker build commands as these can get quite long. You can replace this file with a scripting language of your choice.

CI

The CI is configured in the ci.yaml file. By containerizing the toolchain, the CI relies on the toolchain we defined in the Dockerfile and doesn't require any custom setup.

Related Blog

Containerize your local Go developer environment series

Read more

• Docker build reference documentation
• Experimental Dockerfile syntax