Daemon

• SystemD

daemon provides a clap-compatible daemon command backed directly by the systemd D-Bus API. Configuration-file loading is intentionally outside this crate.

Features

• install, uninstall/remove, start, stop, restart, and status
• install -- [args...] forwards arguments to ExecStart
• Structured SystemdUnit models [Unit], [Service], and [Install]
• Root users use the system systemd manager
• Non-root users use systemd --user and install to ~/.config/systemd/user
• Detailed state transitions and error context are printed for every action

Embed In A Clap CLI

Use DaemonCli when service metadata is supplied by command-line options:

use anyhow::Result;
use clap::Parser;
use daemon_rs::DaemonCli;

#[derive(Debug, Parser)]
struct Cli {
    #[command(flatten)]
    daemon: DaemonCli,
}

fn main() -> Result<()> {
    Cli::parse().daemon.execute()
}

Example invocation:

my-app \
  --name my-app \
  --description "My application" \
  --program /usr/local/bin/my-app \
  --workdir /var/lib/my-app \
  install -- --config /etc/my-app/config.toml

config_dir defaults to workdir. Optional --user and --group are available for system services; user-level services run as the current user and must not set these fields.

Embed With Programmatic Metadata

Use Daemon and Command when metadata is already available in the host application:

use daemon_rs::{Command, Daemon};
use std::ffi::OsString;

let daemon = Daemon::new(
    "my-app",
    "My application",
    "/usr/local/bin/my-app",
    "/var/lib/my-app",
)
.config_dir("/etc/my-app");

daemon.execute(&Command::Install {
    args: vec![OsString::from("--config"), OsString::from("/etc/my-app/config.toml")],
})?;

The generated model can be inspected before installation:

let unit = daemon.systemd_unit()?;
println!("{}", unit.render());

Commands

Command	Aliases
install	i
uninstall	rm, remove, uni, un
start	run
stop
restart	r, re
status	info, if

The D-Bus session/system bus must be available. The lifecycle integration test requires an active user systemd session:

cargo test
cargo test --test systemd systemd_lifecycle -- --ignored