Add Opentelemetry tracing

Cargo.toml

@@ -10,3 +10,10 @@ reqwest = { version = "0.11", default-features = false, features = ["json", "rus
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 eyre = "0.6"
+
+# Insights
+tower-http = { version = "0.4", features = ["trace"] }
+tracing = "0.1"
+axum-tracing-opentelemetry = { version = "0.10", features = ["otlp", "tracing_subscriber_ext"] }
+opentelemetry = { version = "0.19", features = ["rt-tokio"] }
+tracing-opentelemetry = "0.18"

src/lifecycle/mod.rs

@@ -0,0 +1 @@
+pub mod shutdown;

src/lifecycle/shutdown.rs

@@ -0,0 +1,26 @@
+pub async fn shutdown_signal() {
+    let ctrl_c = async {
+        tokio::signal::ctrl_c()
+            .await
+            .expect("failed to install Ctrl+C handler");
+    };
+
+    #[cfg(unix)]
+        let terminate = async {
+        tokio::signal::unix::signal(tokio::signal::unix::SignalKind::terminate())
+            .expect("failed to install signal handler")
+            .recv()
+            .await;
+    };
+
+    #[cfg(not(unix))]
+        let terminate = std::future::pending::<()>();
+
+    tokio::select! {
+        _ = ctrl_c => {},
+        _ = terminate => {},
+    }
+
+    tracing::warn!("signal received, starting graceful shutdown");
+    opentelemetry::global::shutdown_tracer_provider();
+}

src/main.rs

@@ -1,10 +1,13 @@
 mod collectors;
+mod lifecycle;
 
-use axum::routing::get;
-use axum::Router;
+use axum::{Router, BoxError};
 use axum::extract::Path;
 use axum::http::StatusCode;
-use axum::response::IntoResponse;
+use axum::response::{IntoResponse};
+use axum::routing::get;
+use axum_tracing_opentelemetry::{response_with_trace_layer, opentelemetry_tracing_layer};
+use std::net::SocketAddr;
 use collectors::PromMetric;
 
 fn convert_into_metrics(data: Vec<impl PromMetric>) -> String {
@@ -36,15 +39,22 @@ async fn stats(Path(rsn): Path<String>) -> impl IntoResponse {
 
 
 #[tokio::main]
-async fn main() {
+async fn main() -> Result<(), BoxError> {
+    axum_tracing_opentelemetry::tracing_subscriber_ext::init_subscribers()?;
+
     let app = Router::new()
         .route("/worlds", get(worlds))
-        .route("/stats/:rsn", get(stats));
+        .route("/stats/:rsn", get(stats))
+        .layer(response_with_trace_layer())
+        .layer(opentelemetry_tracing_layer());
 
-    println!("Starting...");
+    let addr = SocketAddr::from(([0, 0, 0, 0], 3030));
 
+    tracing::warn!("listening on {}", addr);
     axum::Server::bind(&"0.0.0.0:3030".parse().unwrap())
         .serve(app.into_make_service())
-        .await
-        .unwrap();
+        .with_graceful_shutdown(lifecycle::shutdown::shutdown_signal())
+        .await?;
+
+    Ok(())
 }