[model-gateway] Wire classify pipeline to gRPC router (#16098)

Co-authored-by: Chang Su <chang.s.su@oracle.com>

sgl-model-gateway/src/routers/grpc/router.rs

@@ -27,6 +27,7 @@ use crate::{
     observability::metrics::{metrics_labels, Metrics},
     protocols::{
         chat::ChatCompletionRequest,
+        classify::ClassifyRequest,
         embedding::EmbeddingRequest,
         generate::GenerateRequest,
         responses::{ResponsesGetParams, ResponsesRequest},
@@ -41,7 +42,8 @@ pub struct GrpcRouter {
     worker_registry: Arc<WorkerRegistry>,
     pipeline: RequestPipeline,
     harmony_pipeline: RequestPipeline,
-    embedding_pipeline: RequestPipeline, // New field for embedding pipeline
+    embedding_pipeline: RequestPipeline,
+    classify_pipeline: RequestPipeline,
     shared_components: Arc<SharedComponents>,
     responses_context: responses::ResponsesContext,
     harmony_responses_context: responses::ResponsesContext,
@@ -99,6 +101,10 @@ impl GrpcRouter {
         let embedding_pipeline =
             RequestPipeline::new_embeddings(worker_registry.clone(), _policy_registry.clone());
 
+        // Create Classify pipeline
+        let classify_pipeline =
+            RequestPipeline::new_classify(worker_registry.clone(), _policy_registry.clone());
+
         // Extract shared dependencies for responses contexts
         let mcp_manager = ctx
             .mcp_manager
@@ -128,6 +134,7 @@ impl GrpcRouter {
             pipeline,
             harmony_pipeline,
             embedding_pipeline,
+            classify_pipeline,
             shared_components,
             responses_context,
             harmony_responses_context,
@@ -324,6 +331,25 @@ impl GrpcRouter {
             )
             .await
     }
+
+    /// Main route_classify implementation
+    async fn route_classify_impl(
+        &self,
+        headers: Option<&HeaderMap>,
+        body: &ClassifyRequest,
+        model_id: Option<&str>,
+    ) -> Response {
+        debug!("Processing classify request for model: {:?}", model_id);
+
+        self.classify_pipeline
+            .execute_classify(
+                Arc::new(body.clone()),
+                headers.cloned(),
+                model_id.map(|s| s.to_string()),
+                self.shared_components.clone(),
+            )
+            .await
+    }
 }
 
 impl std::fmt::Debug for GrpcRouter {
@@ -390,6 +416,15 @@ impl RouterTrait for GrpcRouter {
         self.route_embeddings_impl(headers, body, model_id).await
     }
 
+    async fn route_classify(
+        &self,
+        headers: Option<&HeaderMap>,
+        body: &ClassifyRequest,
+        model_id: Option<&str>,
+    ) -> Response {
+        self.route_classify_impl(headers, body, model_id).await
+    }
+
     fn router_type(&self) -> &'static str {
         "grpc"
     }