Add additional header to BBR for debugging purposes

Author: rramkumar1

pkg/body-based-routing/handlers/request.go

@@ -29,7 +29,10 @@ import (
 	logutil "sigs.k8s.io/gateway-api-inference-extension/pkg/epp/util/logging"
 )
 
-const modelHeader = "X-Gateway-Model-Name"
+const (
+	modelHeader     = "X-Gateway-Model-Name"
+	processedHeader = "X-Gateway-BBR"
+)
 
 // HandleRequestBody handles request bodies.
 func (s *Server) HandleRequestBody(ctx context.Context, data map[string]any) ([]*eppb.ProcessingResponse, error) {
@@ -79,14 +82,7 @@ func (s *Server) HandleRequestBody(ctx context.Context, data map[string]any) ([]
 					Response: &eppb.CommonResponse{
 						ClearRouteCache: true,
 						HeaderMutation: &eppb.HeaderMutation{
-							SetHeaders: []*basepb.HeaderValueOption{
-								{
-									Header: &basepb.HeaderValue{
-										Key:      modelHeader,
-										RawValue: []byte(modelStr),
-									},
-								},
-							},
+							SetHeaders: headersToAdd(modelStr),
 						},
 					},
 				},
@@ -104,14 +100,7 @@ func (s *Server) HandleRequestBody(ctx context.Context, data map[string]any) ([]
 						// Necessary so that the new headers are used in the routing decision.
 						ClearRouteCache: true,
 						HeaderMutation: &eppb.HeaderMutation{
-							SetHeaders: []*basepb.HeaderValueOption{
-								{
-									Header: &basepb.HeaderValue{
-										Key:      modelHeader,
-										RawValue: []byte(modelStr),
-									},
-								},
-							},
+							SetHeaders: headersToAdd(modelStr),
 						},
 					},
 				},
@@ -120,6 +109,23 @@ func (s *Server) HandleRequestBody(ctx context.Context, data map[string]any) ([]
 	}, nil
 }
 
+func headersToAdd(model string) []*basepb.HeaderValueOption {
+	return []*basepb.HeaderValueOption{
+		{
+			Header: &basepb.HeaderValue{
+				Key:      modelHeader,
+				RawValue: []byte(model),
+			},
+		},
+		{
+			Header: &basepb.HeaderValue{
+				Key:      processedHeader,
+				RawValue: []byte("true"),
+			},
+		},
+	}
+}
+
 func addStreamedBodyResponse(responses []*eppb.ProcessingResponse, requestBodyBytes []byte) []*eppb.ProcessingResponse {
 	return append(responses, &extProcPb.ProcessingResponse{
 		Response: &extProcPb.ProcessingResponse_RequestBody{

pkg/body-based-routing/handlers/request_test.go

@@ -117,6 +117,12 @@ func TestHandleRequestBody(t *testing.T) {
 												RawValue: []byte("foo"),
 											},
 										},
+										{
+											Header: &basepb.HeaderValue{
+												Key:      "X-Gateway-BBR",
+												RawValue: []byte("true"),
+											},
+										},
 									},
 								},
 							},
@@ -146,6 +152,12 @@ func TestHandleRequestBody(t *testing.T) {
 												RawValue: []byte("foo"),
 											},
 										},
+										{
+											Header: &basepb.HeaderValue{
+												Key:      "X-Gateway-BBR",
+												RawValue: []byte("true"),
+											},
+										},
 									},
 								},
 							},

test/integration/bbr/hermetic_test.go

@@ -54,6 +54,12 @@ func TestBodyBasedRouting(t *testing.T) {
 						RawValue: []byte("llama"),
 					},
 				},
+				{
+					Header: &configPb.HeaderValue{
+						Key:      "X-Gateway-BBR",
+						RawValue: []byte("true"),
+					},
+				},
 			},
 			wantErr: false,
 		},