added tracing

engine/Cargo.toml

@@ -7,3 +7,5 @@ members = ["crates/*"]
 tokio = { version = "1.35.1", features = ["full"] }
 color-eyre = "0.6.2"
 axum = "0.7.4"
+tracing = "0.1.40"
+tracing-subscriber = "0.3.18"

engine/crates/engine/Cargo.toml

@@ -9,3 +9,5 @@ edition = "2021"
 tokio.workspace = true
 color-eyre.workspace = true
 axum.workspace = true
+tracing.workspace = true
+tracing-subscriber.workspace = true

engine/crates/engine/src/main.rs

@@ -1,14 +1,22 @@
 use axum::{routing::get, Router};
 use color_eyre::eyre::Result;
+use tracing::info;
 
 #[tokio::main]
 async fn main() -> Result<()> {
   color_eyre::install()?;
+  let subscriber = tracing_subscriber::fmt().finish();
+  tracing::subscriber::set_global_default(subscriber)?;
 
   let app = Router::new().route("/", get(|| async { "Hello, World!" }));
 
   // run our app with hyper, listening globally on port 3000
-  let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await?;
+  let port = std::env::var("PORT").unwrap_or_else(|_| "3000".to_string());
+  let host = std::env::var("HOST").unwrap_or_else(|_| "0.0.0.0".to_string());
+  let address = format!("{}:{}", host, port);
+  let listener = tokio::net::TcpListener::bind(&address).await?;
+
+  info!("Listening on {}", address);
   axum::serve(listener, app).await?;
 
   Ok(())