unitard - automatically deploy a systemd unit file from your application

Synopsis

import "github.com/tardisx/unitard"

func main() {
  appName := "coolapp"
  if deploy {
    // error checking ignored for this example
    unit, _ := unitard.NewUnit(appName)
    unit.Deploy()
    os.Exit(0)
  }
  // rest of your application here
}

What it does

This package provides a simple interface to automatically creating and enabling a systemd "user unit" service, as part of your single-binary deployment.

The Deploy() function creates the systemd unit file, reloads the systemd daemon so it reads it, enables the unit (to start on boot) and starts the service running.

Copy your executable to "somewhere" on your target system, run it with -deploy (or however you have enabled the call to Deploy()) and your application starts running in the background and will restart on boot.

There is also an Undeploy() func, which you should of course provide as an option to your users. It stops the running service, removes the unit file and reloads the systemd daemon.

While it does shell out to call the systemctl tool, this does mean this package adds no new non-core dependencies to your project.

What's with the name?

It's the systemd UNIT for Automatic Restart Deployment. Or, just a stupid pun based on my username.

Does this work for root?

It's designed to not. It leverages the systemd --user facility, where users can configure their own services to run persistently, with all configuration being done out of their home directory (in ~/.config/systemd).

See https://wiki.archlinux.org/title/Systemd/User for more information.

It works! Until I logout, and then my program stops!

You need to enable "lingering" - see the link above.

I want it to do X

It's designed to be almost zero configuration - you just provide an application name (which gets used to name the .service file). This is by intent.

However it's not impossible that there are sensible user-configurable things. Raise an issue.