From 3d82c0f17f45eda31e89162c572a116846c60829 Mon Sep 17 00:00:00 2001
From: fzyzcjy <5236035+fzyzcjy@users.noreply.github.com>
Date: Thu, 11 Dec 2025 00:30:53 +0800
Subject: [PATCH] [model-gateway] support engine response http status
 statistics in router (#14712)

---
 sgl-model-gateway/src/observability/metrics.rs | 13 +++++++++++++
 sgl-model-gateway/src/routers/http/router.rs   |  2 ++
 2 files changed, 15 insertions(+)

diff --git a/sgl-model-gateway/src/observability/metrics.rs b/sgl-model-gateway/src/observability/metrics.rs
index 33fb6490c..ad8f93b1a 100644
--- a/sgl-model-gateway/src/observability/metrics.rs
+++ b/sgl-model-gateway/src/observability/metrics.rs
@@ -36,6 +36,10 @@ pub fn init_metrics() {
         "sgl_router_request_errors_total",
         "Total number of request errors by route and error type"
     );
+    describe_counter!(
+        "sgl_router_upstream_http_responses_total",
+        "Total number of upstream engine HTTP responses by status code"
+    );
     describe_counter!(
         "sgl_router_retries_total",
         "Total number of request retries by route"
@@ -325,6 +329,15 @@ impl RouterMetrics {
         .increment(1);
     }
 
+    // TODO unify metric names
+    pub fn record_upstream_http_response(route: &str, status_code: u16) {
+        counter!("sgl_router_upstream_http_responses_total",
+            "route" => route.to_string(),
+            "status_code" => status_code.to_string()
+        )
+        .increment(1);
+    }
+
     pub fn record_retry(route: &str) {
         counter!("sgl_router_retries_total",
             "route" => route.to_string()
diff --git a/sgl-model-gateway/src/routers/http/router.rs b/sgl-model-gateway/src/routers/http/router.rs
index 7aad2c3f7..73b049abf 100644
--- a/sgl-model-gateway/src/routers/http/router.rs
+++ b/sgl-model-gateway/src/routers/http/router.rs
@@ -531,6 +531,8 @@ impl Router {
             }
         };
 
+        RouterMetrics::record_upstream_http_response(route, res.status().as_u16());
+
         let status = StatusCode::from_u16(res.status().as_u16())
             .unwrap_or(StatusCode::INTERNAL_SERVER_ERROR);