feat: add conditional, allows adding or waiting for close

crates/mad/Cargo.toml

@@ -4,8 +4,8 @@ version.workspace = true
 description = "notmad is a life-cycle manager for long running rust operations"
 license = "MIT"
 repository = "https://github.com/kjuulh/mad"
-author = "kjuulh"
-edition = "2021"
+authors = ["kjuulh"]
+edition = "2024"
 
 [dependencies]
 anyhow.workspace = true

crates/mad/src/lib.rs

@@ -1,10 +1,14 @@
 use futures::stream::FuturesUnordered;
 use futures_util::StreamExt;
 use std::{fmt::Display, sync::Arc};
-use tokio::signal::unix::{signal, SignalKind};
+use tokio::signal::unix::{SignalKind, signal};
 
 use tokio_util::sync::CancellationToken;
 
+use crate::waiter::Waiter;
+
+mod waiter;
+
 #[derive(thiserror::Error, Debug)]
 pub enum MadError {
     #[error("component failed: {0}")]
@@ -70,6 +74,17 @@ impl Mad {
         self
     }
 
+    pub fn add_conditional(&mut self, condition: bool, component: impl IntoComponent) -> &mut Self {
+        if condition {
+            self.components.push(component.into_component());
+        } else {
+            self.components
+                .push(Waiter::new(component.into_component()).into_component())
+        }
+
+        self
+    }
+
     pub fn add_fn<F, Fut>(&mut self, f: F) -> &mut Self
     where
         F: Fn(CancellationToken) -> Fut + Send + Sync + 'static,
@@ -100,7 +115,7 @@ impl Mad {
             (Err(run), Err(close)) => {
                 return Err(MadError::AggregateError(AggregateError {
                     errors: vec![run, close],
-                }))
+                }));
             }
             (Ok(_), Ok(_)) => {}
             (Ok(_), Err(close)) => return Err(close),

crates/mad/src/waiter.rs

@@ -0,0 +1,32 @@
+use std::sync::Arc;
+
+use async_trait::async_trait;
+use tokio_util::sync::CancellationToken;
+
+use crate::{Component, MadError};
+
+pub struct Waiter {
+    comp: Arc<dyn Component + Send + Sync + 'static>,
+}
+
+impl Waiter {
+    pub fn new(c: Arc<dyn Component + Send + Sync + 'static>) -> Self {
+        Self { comp: c }
+    }
+}
+
+#[async_trait]
+impl Component for Waiter {
+    fn name(&self) -> Option<String> {
+        match self.comp.name() {
+            Some(name) => Some(format!("waiter/{name}")),
+            None => Some("waiter".into()),
+        }
+    }
+
+    async fn run(&self, cancellation_token: CancellationToken) -> Result<(), MadError> {
+        cancellation_token.cancelled().await;
+
+        Ok(())
+    }
+}