muts - Go package with utilities to create Make-like files in Go

Example of a make.go

package main

import (
	"flag"
	. "github.com/bolcom/muts"
)

var BuildNumber = flag.String("buildnumber", "0", "build sequence number")

func main() {
	flag.Parse()

	Task("clean", taskClean)
	Task("readme", func() { Call("cp -v readme.md ./target/") } )
	Task("build", taskBuild)

	RunTasksFromArgs()
}

func taskClean() {
	Call("rm -rf target")
}
func taskBuild() { ... }

Use it like this

go run make.go -buildnumber=42 build

Some background

This package contains a collection of small helper functions to create scripts the easy way. Most of the time, shell scripting is fine but soon it can become complex once you need functions,loops and decision trees. So why not use the Go language and its rich SDK to write real programs which can be organized much easier.

It all started with the Call function that mimics what you would write in a shell script. It can be used both with a single line command and one that is composed of a list of strings. The CallBackground version lets you wait for the program to finish or return the process ID for stopping it later.

Call("zip -q -r", fmt.Sprintf("%s/sql/boqs-db-%s.zip", versionDir, *DeployableVersion), ".")

Next, we added the concept of a simple task (without the dependencies). A task is just a no-argument function. By putting these tasks in the global Tasks map, you can execute them just by passing their names to your program:

go run make.go clean build unit

The last feature to mention is the Workspace variable that refers to the directory in which the program was started. Task execution may change this directory (Chdir) so to keep things simpler, the current directory is reset after each task.

Most functions will produce a log entry. If an error occurs then the program exits (calling the Abort function).

Defer tasks

You can put tasks on a global defer list which are run just before a program exits. This can be useful to stop processes that were started during the make even when tasks fail to run and ask to abort the program.

E.g. you start multiple Docker containers using different tasks for a local testing environment. Then you run your tests but they fail and you want to abort the build. All running containers must be stopped before exiting the build program. You can add a task to the defer list which is run when a task is abort or when the program panics.

Defer("stop-my-container")

All deferred tasks are run as part of the call to RunTasksFromArgs.

Documentation on go.dev

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