added docker image update option

WatcherAgent/src/serverclientcomm.rs

@@ -0,0 +1,60 @@
+use bollard::Docker;
+use bollard::image::CreateImageOptions;
+use bollard::container::{RestartContainerOptions};
+
+pub fn parse_message(raw: &str) -> ServerMessage {
+    match raw {
+        "restart" => ServerMessage::Restart,
+        "update" => ServerMessage::Update,
+        msg if msg.starts_with("log:") => ServerMessage::Log(msg[4..].to_string()),
+        msg if msg.starts_with("update:") => ServerMessage::Update(msg[7..].to_string()),
+        _ => ServerMessage::Unknown,
+    }
+}
+
+pub async fn handle_server_message(docker: &Docker, msg: ServerMessage) {
+    match msg {
+        ServerMessage::Update(version) => update_docker_image(docker, &version).await,
+        ServerMessage::Restart => restart_container(docker).await,
+        ServerMessage::Unknown => eprintln!("Unknown message"),
+    }
+}
+
+pub async fn update_docker_image(docker: &Docker, image: &str) {
+    println!("Updating to {}", image);
+
+    // 1. Pull new image
+    let mut stream = docker.create_image(
+        Some(CreateImageOptions {
+            from_image: image,
+            ..Default::default()
+        }),
+        None,
+        None,
+    );
+
+    while let Some(progress) = stream.try_next().await.unwrap_or(None) {
+        if let Some(status) = progress.status {
+            println!("Pull status: {}", status);
+        }
+    }
+
+    // 2. Restart the current container
+    if let Ok(container_id) = std::env::var("HOSTNAME") {
+        println!("Restarting container: {}", container_id);
+        docker.restart_container(&container_id, Some(RestartContainerOptions { t: 0 }))
+            .await
+            .unwrap();
+    } else {
+        eprintln!("No container ID found (HOSTNAME not set?)");
+    }
+}
+
+pub async fn restart_container(docker: &Docker) {
+    if let Ok(container_id) = std::env::var("HOSTNAME") {
+        println!("Restarting container {}", container_id);
+        docker.restart_container(&container_id, Some(RestartContainerOptions { t: 0 }))
+            .await
+            .unwrap();
+    }
+}