feat: add tracing

src/main.rs

@@ -1,3 +1,4 @@
+use env_logger::Env;
 use learn_axum::configuration::get_configuration;
 use learn_axum::startup;
 use sqlx::PgPool;
@@ -5,7 +6,9 @@ use tokio::net::TcpListener;
 
 #[tokio::main]
 /// Entry point for the application.
+/// Log level default can be overridden with the RUST_LOG environment variable.
 async fn main() {
+    env_logger::Builder::from_env(Env::default().default_filter_or("info")).init();
     let configuration = get_configuration().expect("Failed to read configuration.");
     let addr = format!("127.0.0.1:{}", configuration.application_port);
     let listener = TcpListener::bind(addr).await.unwrap(); //.expect("Unable to bind to port");

src/routes/subscriptions.rs

@@ -14,7 +14,18 @@ struct FormData {
 }
 
 async fn subscribe(State(pool): State<PgPool>, Form(form): Form<FormData>) {
-    let _ = sqlx::query!(
+    let request_id = Uuid::new_v4();
+    tracing::info!(
+        "request_id {} - Adding '{}' '{}' as a new subscriber.",
+        request_id,
+        form.email,
+        form.name
+    );
+    tracing::info!(
+        "request_id {} - Saving new subscriber details in the database",
+        request_id
+    );
+    match sqlx::query!(
         r#"
         INSERT INTO subscriptions (id, email, name, subscribed_at)
         VALUES ($1, $2, $3, $4)
@@ -27,7 +38,22 @@ async fn subscribe(State(pool): State<PgPool>, Form(form): Form<FormData>) {
     // We use `get_ref` to get an immutable reference to the `PgConnection`
     // wrapped by `web::Data`.
     .execute(&pool)
-    .await;
+    .await
+    {
+        Ok(_) => {
+            tracing::info!(
+                "request_id {} - New subscriber details have been saved",
+                request_id
+            );
+        }
+        Err(e) => {
+            tracing::error!(
+                "request_id {} - Failed to execute query: {:?}",
+                request_id,
+                e
+            );
+        }
+    };
 }
 
 pub fn routes_subscriptions(pool: PgPool) -> Router {