feat: update readme with gif

Signed-off-by: kjuulh <contact@kjuulh.io>

examples/worker/src/main.rs

@@ -0,0 +1,87 @@
+use std::{future::Future, time::Duration};
+
+use noprocess::{HandleID, Process, ProcessHandler, ProcessManager, ProcessResult};
+use tokio_util::sync::CancellationToken;
+
+#[tokio::main]
+async fn main() -> Result<(), noprocess::Error> {
+    tracing_subscriber::fmt::init();
+
+    let manager = ProcessManager::new();
+
+    // Start with 2 workers
+    println!("--- Starting 2 workers ---");
+    let mut workers = vec![];
+    for i in 0..2 {
+        let id = spawn_worker(&manager, i).await;
+        workers.push(id);
+    }
+
+    tokio::time::sleep(Duration::from_secs(2)).await;
+
+    // Scale up to 4 workers
+    println!("\n--- Scaling up to 4 workers ---");
+    for i in 2..4 {
+        let id = spawn_worker(&manager, i).await;
+        workers.push(id);
+    }
+
+    tokio::time::sleep(Duration::from_secs(2)).await;
+
+    // Scale down to 2 workers
+    println!("\n--- Scaling down to 2 workers ---");
+    for id in workers.drain(2..) {
+        manager.stop_process(&id).await?;
+    }
+
+    tokio::time::sleep(Duration::from_secs(2)).await;
+
+    // Stop all remaining workers
+    println!("\n--- Stopping all workers ---");
+    for id in workers {
+        manager.stop_process(&id).await?;
+    }
+
+    println!("All workers stopped");
+    Ok(())
+}
+
+async fn spawn_worker(manager: &ProcessManager, id: usize) -> HandleID {
+    let process = Process::builder(Worker { id })
+        .handle_id(format!("worker-{id}"))
+        .build();
+
+    let handle_id = manager.add_process(process).await;
+    manager.start_process(&handle_id).await.unwrap();
+    handle_id
+}
+
+struct Worker {
+    id: usize,
+}
+
+impl ProcessHandler for Worker {
+    fn call(&self, cancel: CancellationToken) -> impl Future<Output = ProcessResult> + Send {
+        let id = self.id;
+        async move {
+            println!("[worker-{id}] started");
+            let mut interval = tokio::time::interval(Duration::from_millis(500));
+            let mut jobs = 0;
+
+            loop {
+                tokio::select! {
+                    _ = cancel.cancelled() => {
+                        println!("[worker-{id}] stopping after {jobs} jobs");
+                        break;
+                    }
+                    _ = interval.tick() => {
+                        // Simulate doing work
+                        jobs += 1;
+                        println!("[worker-{id}] completed job #{jobs}");
+                    }
+                }
+            }
+            Ok(())
+        }
+    }
+}