tosub 2.2.2

A subsystem lifecycle management library for tokio applications
Documentation 
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/*
 *  Copyright (C) 2025 Michael Bachmann
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

use miette::{Context, bail};
use std::{io, time::Duration};
use tracing::level_filters::LevelFilter;
use tracing_subscriber::{EnvFilter, Layer, fmt, layer::SubscriberExt, util::SubscriberInitExt};

#[tokio::main]
async fn main() -> miette::Result<()> {
    tracing_subscriber::registry()
        .with(
            fmt::Layer::new().with_writer(io::stderr).with_filter(
                EnvFilter::builder()
                    .with_default_directive(LevelFilter::INFO.into())
                    .from_env_lossy(),
            ),
        )
        .init();

    tosub::build_root("hello_world")
        .catch_signals()
        .with_timeout(Duration::from_secs(5))
        .start(run)
        .await?;

    Ok(())
}

async fn run(root: tosub::Subsystem) -> miette::Result<()> {
    root.spawn("child 1", |_| async {
        do_the_third_thing().wrap_err("failed to do the third thing")
    });

    Ok(())
}

fn do_the_third_thing() -> miette::Result<()> {
    do_the_second_thing().wrap_err("failed to do the second thing")?;
    Ok(())
}

fn do_the_second_thing() -> miette::Result<()> {
    do_the_first_thing().wrap_err("failed to do the first thing")?;
    Ok(())
}

fn do_the_first_thing() -> miette::Result<()> {
    bail!("aargh")
}