[router] Forward all request headers from router to workers (#3070)

scripts/killall_sglang.sh

 #!/bin/bash
 
+# Check if sudo is available
+if command -v sudo >/dev/null 2>&1; then
+    sudo apt-get update
+    sudo apt-get install -y lsof
+else
+    apt-get update
+    apt-get install -y lsof
+fi
+
 # Show current GPU status
 nvidia-smi
 

sgl-router/py_test/test_launch_server.py

@@ -22,6 +22,7 @@ def popen_launch_router(
     timeout: float,
     policy: str = "cache_aware",
     max_payload_size: int = None,
+    api_key: str = None,
 ):
     """
     Launch the router server process.
@@ -33,6 +34,7 @@ def popen_launch_router(
         timeout: Server launch timeout
         policy: Router policy, one of "cache_aware", "round_robin", "random"
         max_payload_size: Maximum payload size in bytes
+        api_key: API key for the router
     """
     _, host, port = base_url.split(":")
     host = host[2:]
@@ -55,6 +57,9 @@ def popen_launch_router(
         policy,
     ]
 
+    if api_key is not None:
+        command.extend(["--api-key", api_key])
+
     if max_payload_size is not None:
         command.extend(["--router-max-payload-size", str(max_payload_size)])
 
@@ -333,6 +338,57 @@ class TestLaunchServer(unittest.TestCase):
                 f"1.2MB payload should fail with 413 but got status {response.status_code}",
             )
 
+    def test_5_api_key(self):
+        print("Running test_5_api_key...")
+
+        self.process = popen_launch_router(
+            self.model,
+            self.base_url,
+            dp_size=1,
+            timeout=DEFAULT_TIMEOUT_FOR_SERVER_LAUNCH,
+            policy="round_robin",
+            api_key="correct_api_key",
+        )
+
+        # # Test case 1: request without api key should fail
+        with requests.Session() as session:
+            response = session.post(
+                f"{self.base_url}/generate",
+                json={"text": "Kanye west is, ", "temperature": 0},
+            )
+            print(f"status code: {response.status_code}, response: {response.text}")
+            self.assertEqual(
+                response.status_code,
+                401,
+                "Request without api key should fail with 401",
+            )
+
+        # Test case 2: request with invalid api key should fail
+        with requests.Session() as session:
+            response = requests.post(
+                f"{self.base_url}/generate",
+                json={"text": "Kanye west is, ", "temperature": 0},
+                headers={"Authorization": "Bearer 123"},
+            )
+            print(f"status code: {response.status_code}, response: {response.text}")
+            self.assertEqual(
+                response.status_code,
+                401,
+                "Request with invalid api key should fail with 401",
+            )
+
+        # Test case 3: request with correct api key should succeed
+        with requests.Session() as session:
+            response = session.post(
+                f"{self.base_url}/generate",
+                json={"text": "Kanye west is ", "temperature": 0},
+                headers={"Authorization": "Bearer correct_api_key"},
+            )
+            print(f"status code: {response.status_code}, response: {response.text}")
+            self.assertEqual(
+                response.status_code, 200, "Request with correct api key should succeed"
+            )
+
 
 if __name__ == "__main__":
     unittest.main()

sgl-router/src/router.rs

@@ -12,6 +12,18 @@ use std::thread;
 use std::time::Duration;
 use tokio;
 
+fn copy_request_headers(req: &HttpRequest) -> Vec<(String, String)> {
+    req.headers()
+        .iter()
+        .filter_map(|(name, value)| {
+            value
+                .to_str()
+                .ok()
+                .map(|v| (name.to_string(), v.to_string()))
+        })
+        .collect()
+}
+
 #[derive(Debug)]
 pub enum Router {
     RoundRobin {
@@ -303,8 +315,18 @@ impl Router {
         client: &reqwest::Client,
         worker_url: &str,
         route: &str,
+        req: &HttpRequest,
     ) -> HttpResponse {
-        match client.get(format!("{}{}", worker_url, route)).send().await {
+        let mut request_builder = client.get(format!("{}{}", worker_url, route));
+
+        // Copy all headers from original request except for /health because it does not need authorization
+        if route != "/health" {
+            for (name, value) in copy_request_headers(req) {
+                request_builder = request_builder.header(name, value);
+            }
+        }
+
+        match request_builder.send().await {
             Ok(res) => {
                 let status = actix_web::http::StatusCode::from_u16(res.status().as_u16())
                     .unwrap_or(actix_web::http::StatusCode::INTERNAL_SERVER_ERROR);
@@ -322,7 +344,12 @@ impl Router {
         }
     }
 
-    pub async fn route_to_first(&self, client: &reqwest::Client, route: &str) -> HttpResponse {
+    pub async fn route_to_first(
+        &self,
+        client: &reqwest::Client,
+        route: &str,
+        req: &HttpRequest,
+    ) -> HttpResponse {
         const MAX_REQUEST_RETRIES: u32 = 3;
         const MAX_TOTAL_RETRIES: u32 = 6;
         let mut total_retries = 0;
@@ -338,10 +365,17 @@ impl Router {
                             info!("Retrying request after {} failed attempts", total_retries);
                         }
 
-                        let response = self.send_request(client, &worker_url, route).await;
+                        let response = self.send_request(client, &worker_url, route, req).await;
 
                         if response.status().is_success() {
                             return response;
+                        } else {
+                            // if the worker is healthy, it means the request is bad, so return the error response
+                            let health_response =
+                                self.send_request(client, &worker_url, "/health", req).await;
+                            if health_response.status().is_success() {
+                                return response;
+                            }
                         }
 
                         warn!(
@@ -496,19 +530,16 @@ impl Router {
             .map(|v| v.get("stream").and_then(|s| s.as_bool()).unwrap_or(false))
             .unwrap_or(false);
 
-        let res = match client
+        let mut request_builder = client
             .post(format!("{}{}", worker_url, route))
-            .header(
-                "Content-Type",
-                req.headers()
-                    .get("Content-Type")
-                    .and_then(|h| h.to_str().ok())
-                    .unwrap_or("application/json"),
-            )
-            .body(body.to_vec())
-            .send()
-            .await
-        {
+            .body(body.to_vec());
+
+        // Copy all headers from original request
+        for (name, value) in copy_request_headers(req) {
+            request_builder = request_builder.header(name, value);
+        }
+
+        let res = match request_builder.send().await {
             Ok(res) => res,
             Err(_) => return HttpResponse::InternalServerError().finish(),
         };
@@ -596,6 +627,13 @@ impl Router {
 
                 if response.status().is_success() {
                     return response;
+                } else {
+                    // if the worker is healthy, it means the request is bad, so return the error response
+                    let health_response =
+                        self.send_request(client, &worker_url, "/health", req).await;
+                    if health_response.status().is_success() {
+                        return response;
+                    }
                 }
 
                 warn!(

sgl-router/src/server.rs

@@ -26,33 +26,37 @@ impl AppState {
 }
 
 #[get("/health")]
-async fn health(data: web::Data<AppState>) -> impl Responder {
-    data.router.route_to_first(&data.client, "/health").await
+async fn health(req: HttpRequest, data: web::Data<AppState>) -> impl Responder {
+    data.router
+        .route_to_first(&data.client, "/health", &req)
+        .await
 }
 
 #[get("/health_generate")]
-async fn health_generate(data: web::Data<AppState>) -> impl Responder {
+async fn health_generate(req: HttpRequest, data: web::Data<AppState>) -> impl Responder {
     data.router
-        .route_to_first(&data.client, "/health_generate")
+        .route_to_first(&data.client, "/health_generate", &req)
         .await
 }
 
 #[get("/get_server_info")]
-async fn get_server_info(data: web::Data<AppState>) -> impl Responder {
+async fn get_server_info(req: HttpRequest, data: web::Data<AppState>) -> impl Responder {
     data.router
-        .route_to_first(&data.client, "/get_server_info")
+        .route_to_first(&data.client, "/get_server_info", &req)
         .await
 }
 
 #[get("/v1/models")]
-async fn v1_models(data: web::Data<AppState>) -> impl Responder {
-    data.router.route_to_first(&data.client, "/v1/models").await
+async fn v1_models(req: HttpRequest, data: web::Data<AppState>) -> impl Responder {
+    data.router
+        .route_to_first(&data.client, "/v1/models", &req)
+        .await
 }
 
 #[get("/get_model_info")]
-async fn get_model_info(data: web::Data<AppState>) -> impl Responder {
+async fn get_model_info(req: HttpRequest, data: web::Data<AppState>) -> impl Responder {
     data.router
-        .route_to_first(&data.client, "/get_model_info")
+        .route_to_first(&data.client, "/get_model_info", &req)
         .await
 }