feat(logging): add a logging middleware to log all api requests (#3437)

crates/router/src/middleware.rs

@@ -1,3 +1,4 @@
+use router_env::tracing::{field::Empty, Instrument};
 /// Middleware to include request ID in response header.
 pub struct RequestId;
 
@@ -48,20 +49,23 @@ where
         let request_id_fut = req.extract::<router_env::tracing_actix_web::RequestId>();
         let response_fut = self.service.call(req);
 
-        Box::pin(async move {
-            let request_id = request_id_fut.await?;
-            let request_id = request_id.as_hyphenated().to_string();
-            if let Some(upstream_request_id) = old_x_request_id {
-                router_env::logger::info!(?request_id, ?upstream_request_id);
-            }
-            let mut response = response_fut.await?;
-            response.headers_mut().append(
-                http::header::HeaderName::from_static("x-request-id"),
-                http::HeaderValue::from_str(&request_id)?,
-            );
+        Box::pin(
+            async move {
+                let request_id = request_id_fut.await?;
+                let request_id = request_id.as_hyphenated().to_string();
+                if let Some(upstream_request_id) = old_x_request_id {
+                    router_env::logger::info!(?request_id, ?upstream_request_id);
+                }
+                let mut response = response_fut.await?;
+                response.headers_mut().append(
+                    http::header::HeaderName::from_static("x-request-id"),
+                    http::HeaderValue::from_str(&request_id)?,
+                );
 
-            Ok(response)
-        })
+                Ok(response)
+            }
+            .in_current_span(),
+        )
     }
 }
 
@@ -81,3 +85,67 @@ pub fn default_response_headers() -> actix_web::middleware::DefaultHeaders {
         .add((header::STRICT_TRANSPORT_SECURITY, "max-age=31536000"))
         .add((header::VIA, "HyperSwitch"))
 }
+
+/// Middleware to build a TOP level domain span for each request.
+pub struct LogSpanInitializer;
+
+impl<S, B> actix_web::dev::Transform<S, actix_web::dev::ServiceRequest> for LogSpanInitializer
+where
+    S: actix_web::dev::Service<
+        actix_web::dev::ServiceRequest,
+        Response = actix_web::dev::ServiceResponse<B>,
+        Error = actix_web::Error,
+    >,
+    S::Future: 'static,
+    B: 'static,
+{
+    type Response = actix_web::dev::ServiceResponse<B>;
+    type Error = actix_web::Error;
+    type Transform = LogSpanInitializerMiddleware<S>;
+    type InitError = ();
+    type Future = std::future::Ready<Result<Self::Transform, Self::InitError>>;
+
+    fn new_transform(&self, service: S) -> Self::Future {
+        std::future::ready(Ok(LogSpanInitializerMiddleware { service }))
+    }
+}
+
+pub struct LogSpanInitializerMiddleware<S> {
+    service: S,
+}
+
+impl<S, B> actix_web::dev::Service<actix_web::dev::ServiceRequest>
+    for LogSpanInitializerMiddleware<S>
+where
+    S: actix_web::dev::Service<
+        actix_web::dev::ServiceRequest,
+        Response = actix_web::dev::ServiceResponse<B>,
+        Error = actix_web::Error,
+    >,
+    S::Future: 'static,
+    B: 'static,
+{
+    type Response = actix_web::dev::ServiceResponse<B>;
+    type Error = actix_web::Error;
+    type Future = futures::future::LocalBoxFuture<'static, Result<Self::Response, Self::Error>>;
+
+    actix_web::dev::forward_ready!(service);
+
+    // TODO: have a common source of truth for the list of top level fields
+    // /crates/router_env/src/logger/storage.rs also has a list of fields  called PERSISTENT_KEYS
+    fn call(&self, req: actix_web::dev::ServiceRequest) -> Self::Future {
+        let response_fut = self.service.call(req);
+
+        Box::pin(
+            response_fut.instrument(
+                router_env::tracing::info_span!(
+                    "golden_log_line",
+                    payment_id = Empty,
+                    merchant_id = Empty,
+                    connector_name = Empty
+                )
+                .or_current(),
+            ),
+        )
+    }
+}