Sub2API v1.0 - AI API 网关（二开初始版本，基于上游 Wei-Shaw/sub2api）

backend/internal/handler/openai_responses_image_intent_benchmark_test.go

@@ -0,0 +1,53 @@
+package handler
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/Wei-Shaw/sub2api/internal/service"
+)
+
+var openAIResponsesImageIntentRoutingBenchmarkSink service.OpenAIEndpointCapability
+
+func BenchmarkOpenAIResponsesImageIntentRouting_LargeToolsBody(b *testing.B) {
+	body := buildLargeOpenAIResponsesToolsBody(32 << 20)
+	if service.IsExplicitImageGenerationIntent("/v1/responses", "gpt-5.4", body) {
+		b.Fatal("large tools body must not have explicit image intent")
+	}
+	platform := service.PlatformOpenAI
+
+	b.Run("reuse_once", func(b *testing.B) {
+		b.SetBytes(int64(len(body)))
+		b.ReportAllocs()
+		for range b.N {
+			imageIntent := service.IsExplicitImageGenerationIntent("/v1/responses", "gpt-5.4", body)
+			openAIResponsesImageIntentRoutingBenchmarkSink = openAIResponsesRequiredCapability(imageIntent, platform)
+		}
+	})
+
+	b.Run("rescan_twice", func(b *testing.B) {
+		b.SetBytes(int64(len(body)))
+		b.ReportAllocs()
+		for range b.N {
+			imageIntent := service.IsExplicitImageGenerationIntent("/v1/responses", "gpt-5.4", body)
+			// 对照优化前路径：路由阶段会再次扫描同一份未修改的 body。
+			requiredCapability := service.OpenAIEndpointCapabilityChatCompletions
+			if service.IsExplicitImageGenerationIntent("/v1/responses", "gpt-5.4", body) && platform == service.PlatformOpenAI {
+				requiredCapability = service.OpenAIEndpointCapabilityResponses
+			}
+			if imageIntent && requiredCapability != service.OpenAIEndpointCapabilityResponses {
+				b.Fatal("explicit image intent must require Responses")
+			}
+			openAIResponsesImageIntentRoutingBenchmarkSink = requiredCapability
+		}
+	})
+}
+
+func buildLargeOpenAIResponsesToolsBody(targetBytes int) []byte {
+	var builder strings.Builder
+	builder.Grow(targetBytes + 256)
+	_, _ = builder.WriteString(`{"model":"gpt-5.4","tools":[{"type":"function","name":"search","description":"`)
+	_, _ = builder.WriteString(strings.Repeat("x", targetBytes))
+	_, _ = builder.WriteString(`"}],"tool_choice":"auto","input":"write code"}`)
+	return []byte(builder.String())
+}