golang-tools

Demo how to install binary dependencies for Go with modules without abusing your code dependencies.

Motivation

Before Go 1.13 solution with tools.go (golang/go#25922) had worked well enough without abusing go.mod/go.sum file by dependencies hidden under a tag. Now with go 1.13.x go mod tidy adds such dependencies to module's go.mod go.sum files, which I want to avoid.

How it works

• binary dependencies described in _tools/linter/tools.go.
  • symbol _ in top level directory name hides dependency code from go build tools.
  • second level directory linter exist because it's allows go tools work properly inside it (go tools don't like directory names with underscores)
• Directory _tools/linter initialized as separate go module (in this case github.com/nordicdyno/golang-tools-linter). This allows track binaries dependencies like it was proposed by «tools.go solution» in golang/go#25922, but without mixing tools and project dependencies.
• Binaries could be installed without any extra tools (except shell), just by running _tools/install.sh.
  • This script just runs ls-imports utility in the context of tools module and sends its output to go install command.
  • The tool ls-imports is carried inside _tools/ls-imports directory and all that it does just prints all imports from provided files.

Why it's better than just putting tools.go inside your module context.

• Your project's binary tools and their dependencies separated from your code.
• Versions of dependencies these extra tools don't collide with your dependencies versions and don't interfere with them in unpredictable ways.

Why it's not an ideal solution

1. Dependencies of binary dependencies still interfere with each other, until we separate them in their own dependency holder modules
2. You need a shell to install tools. (It's easily solvable with docker or a little bit more complicated ls-imports/deps-install tool)

How to use

build binary:

go build

install tools (linter):

make tools-install

run linter:

make lint