Implement Vertex Raw mode support in AI Proxy (#3375)

2026-06-07 11:47:30 +08:00 · 2026-01-21 14:45:06 +08:00
parent 3a28a9b6a7
commit a2eb599eff
4 changed files with 403 additions and 12 deletions
--- a/plugins/wasm-go/extensions/ai-proxy/main_test.go
+++ b/plugins/wasm-go/extensions/ai-proxy/main_test.go
@@ -137,6 +137,10 @@ func TestVertex(t *testing.T) {
 	test.RunVertexExpressModeOnStreamingResponseBodyTests(t)
 	test.RunVertexExpressModeImageGenerationRequestBodyTests(t)
 	test.RunVertexExpressModeImageGenerationResponseBodyTests(t)
+	// Vertex Raw 模式测试
+	test.RunVertexRawModeOnHttpRequestHeadersTests(t)
+	test.RunVertexRawModeOnHttpRequestBodyTests(t)
+	test.RunVertexRawModeOnHttpResponseBodyTests(t)
 }

 func TestBedrock(t *testing.T) {
--- a/plugins/wasm-go/extensions/ai-proxy/provider/provider.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/provider.go
@@ -70,6 +70,7 @@ const (
 	ApiNameGeminiStreamGenerateContent ApiName = "gemini/v1beta/streamgeneratecontent"
 	ApiNameAnthropicMessages           ApiName = "anthropic/v1/messages"
 	ApiNameAnthropicComplete           ApiName = "anthropic/v1/complete"
+	ApiNameVertexRaw                   ApiName = "vertex/raw"

 	// OpenAI
 	PathOpenAIPrefix                               = "/v1"
--- a/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go
+++ b/plugins/wasm-go/extensions/ai-proxy/provider/vertex.go
@@ -44,9 +44,15 @@ const (
 	vertexGlobalRegion                 = "global"
 	contextClaudeMarker                = "isClaudeRequest"
 	contextOpenAICompatibleMarker      = "isOpenAICompatibleRequest"
+	contextVertexRawMarker             = "isVertexRawRequest"
 	vertexAnthropicVersion             = "vertex-2023-10-16"
 )

+// vertexRawPathRegex 匹配原生 Vertex AI REST API 路径
+// 格式: [任意前缀]/{api-version}/projects/{project}/locations/{location}/publishers/{publisher}/models/{model}:{action}
+// 允许任意 basePath 前缀，兼容 basePathHandling 配置
+var vertexRawPathRegex = regexp.MustCompile(`^.*/([^/]+)/projects/([^/]+)/locations/([^/]+)/publishers/([^/]+)/models/([^/:]+):([^/?]+)`)
+
 type vertexProviderInitializer struct{}

 func (v *vertexProviderInitializer) ValidateConfig(config *ProviderConfig) error {
@@ -92,6 +98,7 @@ func (v *vertexProviderInitializer) DefaultCapabilities() map[string]string {
 		string(ApiNameChatCompletion):  vertexPathTemplate,
 		string(ApiNameEmbeddings):      vertexPathTemplate,
 		string(ApiNameImageGeneration): vertexPathTemplate,
+		string(ApiNameVertexRaw):       "", // 空字符串表示保持原路径，不做路径转换
 	}
 }

@@ -143,6 +150,12 @@ func (v *vertexProvider) GetProviderType() string {
 }

 func (v *vertexProvider) GetApiName(path string) ApiName {
+	// 优先匹配原生 Vertex AI REST API 路径，支持任意 basePath 前缀
+	// 格式: [任意前缀]/{api-version}/projects/{project}/locations/{location}/publishers/{publisher}/models/{model}:{action}
+	// 必须在其他 action 检查之前，因为 :predict、:generateContent 等 action 会被其他规则匹配
+	if vertexRawPathRegex.MatchString(path) {
+		return ApiNameVertexRaw
+	}
 	if strings.HasSuffix(path, vertexChatCompletionAction) || strings.HasSuffix(path, vertexChatCompletionStreamAction) {
 		return ApiNameChatCompletion
 	}
@@ -211,6 +224,27 @@ func (v *vertexProvider) OnRequestBody(ctx wrapper.HttpContext, apiName ApiName,
 	if !v.config.isSupportedAPI(apiName) {
 		return types.ActionContinue, errUnsupportedApiName
 	}
+
+	// Vertex Raw 模式: 透传请求体，只做 OAuth 认证
+	// 用于直接访问 Vertex AI REST API，不做协议转换
+	// 注意：此检查必须在 IsOriginal() 之前，因为 Vertex Raw 模式通常与 original 协议一起使用
+	if apiName == ApiNameVertexRaw {
+		ctx.SetContext(contextVertexRawMarker, true)
+		// Express Mode 不需要 OAuth 认证
+		if v.isExpressMode() {
+			return types.ActionContinue, nil
+		}
+		// 标准模式需要获取 OAuth token
+		cached, err := v.getToken()
+		if cached {
+			return types.ActionContinue, nil
+		}
+		if err == nil {
+			return types.ActionPause, nil
+		}
+		return types.ActionContinue, err
+	}
+
 	if v.config.IsOriginal() {
 		return types.ActionContinue, nil
 	}
--- a/plugins/wasm-go/extensions/ai-proxy/test/vertex.go
+++ b/plugins/wasm-go/extensions/ai-proxy/test/vertex.go
@@ -82,12 +82,12 @@ var invalidVertexStandardModeConfig = func() json.RawMessage {
 var vertexOpenAICompatibleModeConfig = func() json.RawMessage {
 	data, _ := json.Marshal(map[string]interface{}{
 		"provider": map[string]interface{}{
-			"type":                    "vertex",
-			"vertexOpenAICompatible":  true,
-			"vertexAuthKey":           `{"type":"service_account","client_email":"test@test.iam.gserviceaccount.com","private_key":"-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC7k1v5C7y8L4SN\n-----END PRIVATE KEY-----\n","token_uri":"https://oauth2.googleapis.com/token"}`,
-			"vertexRegion":            "us-central1",
-			"vertexProjectId":         "test-project-id",
-			"vertexAuthServiceName":   "test-auth-service",
+			"type":                   "vertex",
+			"vertexOpenAICompatible": true,
+			"vertexAuthKey":          `{"type":"service_account","client_email":"test@test.iam.gserviceaccount.com","private_key":"-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC7k1v5C7y8L4SN\n-----END PRIVATE KEY-----\n","token_uri":"https://oauth2.googleapis.com/token"}`,
+			"vertexRegion":           "us-central1",
+			"vertexProjectId":        "test-project-id",
+			"vertexAuthServiceName":  "test-auth-service",
 		},
 	})
 	return data
@@ -97,12 +97,12 @@ var vertexOpenAICompatibleModeConfig = func() json.RawMessage {
 var vertexOpenAICompatibleModeWithModelMappingConfig = func() json.RawMessage {
 	data, _ := json.Marshal(map[string]interface{}{
 		"provider": map[string]interface{}{
-			"type":                    "vertex",
-			"vertexOpenAICompatible":  true,
-			"vertexAuthKey":           `{"type":"service_account","client_email":"test@test.iam.gserviceaccount.com","private_key":"-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC7k1v5C7y8L4SN\n-----END PRIVATE KEY-----\n","token_uri":"https://oauth2.googleapis.com/token"}`,
-			"vertexRegion":            "us-central1",
-			"vertexProjectId":         "test-project-id",
-			"vertexAuthServiceName":   "test-auth-service",
+			"type":                   "vertex",
+			"vertexOpenAICompatible": true,
+			"vertexAuthKey":          `{"type":"service_account","client_email":"test@test.iam.gserviceaccount.com","private_key":"-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC7k1v5C7y8L4SN\n-----END PRIVATE KEY-----\n","token_uri":"https://oauth2.googleapis.com/token"}`,
+			"vertexRegion":           "us-central1",
+			"vertexProjectId":        "test-project-id",
+			"vertexAuthServiceName":  "test-auth-service",
 			"modelMapping": map[string]string{
 				"gpt-4":         "gemini-2.0-flash",
 				"gpt-3.5-turbo": "gemini-1.5-flash",
@@ -124,6 +124,47 @@ var invalidVertexExpressAndOpenAICompatibleConfig = func() json.RawMessage {
 	return data
 }()

+// 测试配置：Vertex Raw 模式配置（Express Mode + 原生 Vertex API 路径）
+var vertexRawModeExpressConfig = func() json.RawMessage {
+	data, _ := json.Marshal(map[string]interface{}{
+		"provider": map[string]interface{}{
+			"type":      "vertex",
+			"apiTokens": []string{"test-api-key-for-raw-mode"},
+			"protocol":  "original",
+		},
+	})
+	return data
+}()
+
+// 测试配置：Vertex Raw 模式配置（标准模式 + 原生 Vertex API 路径）
+var vertexRawModeStandardConfig = func() json.RawMessage {
+	data, _ := json.Marshal(map[string]interface{}{
+		"provider": map[string]interface{}{
+			"type":                  "vertex",
+			"vertexAuthKey":         `{"type":"service_account","client_email":"test@test.iam.gserviceaccount.com","private_key":"-----BEGIN PRIVATE KEY-----\nMIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC7k1v5C7y8L4SN\n-----END PRIVATE KEY-----\n","token_uri":"https://oauth2.googleapis.com/token"}`,
+			"vertexRegion":          "us-central1",
+			"vertexProjectId":       "test-project-id",
+			"vertexAuthServiceName": "test-auth-service",
+			"protocol":              "original",
+		},
+	})
+	return data
+}()
+
+// 测试配置：Vertex Raw 模式配置（Express Mode + basePath removePrefix）
+var vertexRawModeWithBasePathConfig = func() json.RawMessage {
+	data, _ := json.Marshal(map[string]interface{}{
+		"provider": map[string]interface{}{
+			"type":             "vertex",
+			"apiTokens":        []string{"test-api-key-for-raw-mode"},
+			"protocol":         "original",
+			"basePath":         "/vertex-proxy",
+			"basePathHandling": "removePrefix",
+		},
+	})
+	return data
+}()
+
 func RunVertexParseConfigTests(t *testing.T) {
 	test.RunGoTest(t, func(t *testing.T) {
 		// 测试 Vertex 标准模式配置解析
@@ -1231,3 +1272,314 @@ func RunVertexExpressModeImageGenerationResponseBodyTests(t *testing.T) {
 		})
 	})
 }
+
+// ==================== Vertex Raw 模式测试 ====================
+
+func RunVertexRawModeOnHttpRequestHeadersTests(t *testing.T) {
+	test.RunTest(t, func(t *testing.T) {
+		// 测试 Vertex Raw 模式请求头处理（Express Mode + 原生 Vertex API 路径）
+		t.Run("vertex raw mode express - request headers with native vertex path", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeExpressConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 使用原生 Vertex AI REST API 路径
+			action := host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:generateContent"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 应该返回 HeaderStopIteration，因为需要处理请求体
+			require.Equal(t, types.HeaderStopIteration, action)
+
+			// 验证请求头是否被正确处理
+			requestHeaders := host.GetRequestHeaders()
+			require.NotNil(t, requestHeaders)
+
+			// 验证 Host 是否被改为 vertex 域名（Express Mode 使用不带 region 前缀的域名）
+			require.True(t, test.HasHeaderWithValue(requestHeaders, ":authority", "aiplatform.googleapis.com"),
+				"Host header should be changed to vertex domain without region prefix")
+		})
+
+		// 测试 Vertex Raw 模式请求头处理（标准模式 + 原生 Vertex API 路径）
+		t.Run("vertex raw mode standard - request headers with native vertex path", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeStandardConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 使用原生 Vertex AI REST API 路径
+			action := host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:generateContent"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			require.Equal(t, types.HeaderStopIteration, action)
+
+			// 验证请求头是否被正确处理
+			requestHeaders := host.GetRequestHeaders()
+			require.NotNil(t, requestHeaders)
+
+			// 验证 Host 是否被改为 vertex 域名（标准模式使用带 region 前缀的域名）
+			require.True(t, test.HasHeaderWithValue(requestHeaders, ":authority", "us-central1-aiplatform.googleapis.com"),
+				"Host header should be changed to vertex domain with region prefix")
+		})
+
+		// 测试 Vertex Raw 模式请求头处理（带 basePath 前缀）
+		t.Run("vertex raw mode with basePath - request headers", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeWithBasePathConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 使用带 basePath 前缀的原生 Vertex AI REST API 路径
+			action := host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/vertex-proxy/v1/projects/test-project/locations/us-central1/publishers/google/models/imagen-4.0-generate-preview-06-06:predict"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			require.Equal(t, types.HeaderStopIteration, action)
+
+			// 验证请求头是否被正确处理
+			requestHeaders := host.GetRequestHeaders()
+			require.NotNil(t, requestHeaders)
+
+			// 验证 Host 是否被改为 vertex 域名
+			require.True(t, test.HasHeaderWithValue(requestHeaders, ":authority", "aiplatform.googleapis.com"),
+				"Host header should be changed to vertex domain")
+
+			// 验证路径是否移除了 basePath 前缀
+			pathHeader := ""
+			for _, header := range requestHeaders {
+				if header[0] == ":path" {
+					pathHeader = header[1]
+					break
+				}
+			}
+			require.NotContains(t, pathHeader, "/vertex-proxy", "Path should have basePath prefix removed")
+			require.Contains(t, pathHeader, "/v1/projects/", "Path should contain original vertex path after basePath removal")
+		})
+
+		// 测试 Vertex Raw 模式请求头处理（Anthropic 模型路径）
+		t.Run("vertex raw mode express - request headers with anthropic model path", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeExpressConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 使用 Anthropic 模型的原生 Vertex AI REST API 路径
+			action := host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-east5/publishers/anthropic/models/claude-sonnet-4@20250514:rawPredict"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			require.Equal(t, types.HeaderStopIteration, action)
+
+			// 验证请求头是否被正确处理
+			requestHeaders := host.GetRequestHeaders()
+			require.NotNil(t, requestHeaders)
+
+			// 验证 Host 是否被改为 vertex 域名
+			require.True(t, test.HasHeaderWithValue(requestHeaders, ":authority", "aiplatform.googleapis.com"),
+				"Host header should be changed to vertex domain")
+		})
+	})
+}
+
+func RunVertexRawModeOnHttpRequestBodyTests(t *testing.T) {
+	test.RunTest(t, func(t *testing.T) {
+		// 测试 Vertex Raw 模式请求体处理（Express Mode - 透传请求体）
+		t.Run("vertex raw mode express - request body passthrough", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeExpressConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 先设置请求头
+			host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:generateContent"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 设置原生 Vertex 格式的请求体
+			requestBody := `{"contents":[{"role":"user","parts":[{"text":"Hello, world!"}]}],"generationConfig":{"temperature":0.7}}`
+			action := host.CallOnHttpRequestBody([]byte(requestBody))
+
+			// Express Mode 不需要暂停等待 OAuth token
+			require.Equal(t, types.ActionContinue, action)
+
+			// 验证请求体被透传（不做格式转换）
+			processedBody := host.GetRequestBody()
+			require.NotNil(t, processedBody)
+
+			// 请求体应该保持原样
+			require.Equal(t, requestBody, string(processedBody), "Request body should be passed through unchanged")
+		})
+
+		// 测试 Vertex Raw 模式请求体处理（标准模式 - 需要 OAuth token）
+		// 注意：使用 countTokens action，因为 generateContent/predict 等会被识别为其他 API 类型
+		// 注意：在单元测试环境中，由于测试配置使用的是无效的私钥，JWT 创建会失败，
+		// 因此 getToken() 会返回错误，导致 ActionContinue 而不是 ActionPause。
+		// 这个测试主要验证代码正确进入了 Vertex Raw 模式的处理分支，请求体被透传。
+		t.Run("vertex raw mode standard - request body with oauth", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeStandardConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 先设置请求头 - 使用 countTokens action，这是一个不会被其他 API 类型匹配的原生 Vertex API
+			host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:countTokens"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 设置原生 Vertex 格式的请求体
+			requestBody := `{"contents":[{"role":"user","parts":[{"text":"Hello, world!"}]}]}`
+			action := host.CallOnHttpRequestBody([]byte(requestBody))
+
+			// 注意：在单元测试环境中，由于私钥无效，JWT 创建失败会返回 ActionContinue
+			// 在真实环境中，如果 JWT 创建成功，会返回 ActionPause 等待 OAuth token
+			// 这里我们只验证代码正确进入了 Vertex Raw 模式的处理分支
+			require.Equal(t, types.ActionContinue, action)
+
+			// 验证请求体被透传（不做格式转换）
+			processedBody := host.GetRequestBody()
+			require.NotNil(t, processedBody)
+
+			// 请求体应该保持原样（这是 Vertex Raw 模式的核心功能）
+			require.Equal(t, requestBody, string(processedBody), "Request body should be passed through unchanged")
+		})
+
+		// 测试 Vertex Raw 模式请求体处理（带 basePath 前缀 - 路径正确处理）
+		t.Run("vertex raw mode with basePath - request body passthrough", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeWithBasePathConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 先设置请求头（带 basePath 前缀）
+			host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/vertex-proxy/v1/projects/test-project/locations/us-central1/publishers/google/models/imagen-4.0-generate-preview-06-06:predict"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 设置原生 Vertex 格式的请求体（图片生成）
+			requestBody := `{"instances":[{"prompt":"A beautiful sunset"}],"parameters":{"sampleCount":1}}`
+			action := host.CallOnHttpRequestBody([]byte(requestBody))
+
+			// Express Mode 不需要暂停等待 OAuth token
+			require.Equal(t, types.ActionContinue, action)
+
+			// 验证请求体被透传
+			processedBody := host.GetRequestBody()
+			require.NotNil(t, processedBody)
+			require.Equal(t, requestBody, string(processedBody), "Request body should be passed through unchanged")
+
+			// 验证路径已正确处理（移除 basePath）
+			requestHeaders := host.GetRequestHeaders()
+			pathHeader := ""
+			for _, header := range requestHeaders {
+				if header[0] == ":path" {
+					pathHeader = header[1]
+					break
+				}
+			}
+			require.NotContains(t, pathHeader, "/vertex-proxy", "Path should have basePath prefix removed")
+		})
+
+		// 测试 Vertex Raw 模式请求体处理（流式请求）
+		t.Run("vertex raw mode express - streaming request body passthrough", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeExpressConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 先设置请求头（流式端点）
+			host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:streamGenerateContent?alt=sse"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 设置原生 Vertex 格式的请求体
+			requestBody := `{"contents":[{"role":"user","parts":[{"text":"Tell me a story"}]}]}`
+			action := host.CallOnHttpRequestBody([]byte(requestBody))
+
+			require.Equal(t, types.ActionContinue, action)
+
+			// 验证请求体被透传
+			processedBody := host.GetRequestBody()
+			require.NotNil(t, processedBody)
+			require.Equal(t, requestBody, string(processedBody), "Request body should be passed through unchanged")
+		})
+	})
+}
+
+func RunVertexRawModeOnHttpResponseBodyTests(t *testing.T) {
+	test.RunTest(t, func(t *testing.T) {
+		// 测试 Vertex Raw 模式响应体处理（透传响应）
+		t.Run("vertex raw mode express - response body passthrough", func(t *testing.T) {
+			host, status := test.NewTestHost(vertexRawModeExpressConfig)
+			defer host.Reset()
+			require.Equal(t, types.OnPluginStartStatusOK, status)
+
+			// 先设置请求头
+			host.CallOnHttpRequestHeaders([][2]string{
+				{":authority", "example.com"},
+				{":path", "/v1/projects/test-project/locations/us-central1/publishers/google/models/gemini-2.0-flash:generateContent"},
+				{":method", "POST"},
+				{"Content-Type", "application/json"},
+			})
+
+			// 设置请求体
+			requestBody := `{"contents":[{"role":"user","parts":[{"text":"Hello"}]}]}`
+			host.CallOnHttpRequestBody([]byte(requestBody))
+
+			// 设置响应属性
+			host.SetProperty([]string{"response", "code_details"}, []byte("via_upstream"))
+
+			// 设置响应头
+			responseHeaders := [][2]string{
+				{":status", "200"},
+				{"Content-Type", "application/json"},
+			}
+			host.CallOnHttpResponseHeaders(responseHeaders)
+
+			// 设置原生 Vertex 格式的响应体
+			responseBody := `{
+				"candidates": [{
+					"content": {
+						"role": "model",
+						"parts": [{"text": "Hello! How can I help you?"}]
+					},
+					"finishReason": "STOP"
+				}],
+				"usageMetadata": {
+					"promptTokenCount": 5,
+					"candidatesTokenCount": 10,
+					"totalTokenCount": 15
+				}
+			}`
+			action := host.CallOnHttpResponseBody([]byte(responseBody))
+
+			require.Equal(t, types.ActionContinue, action)
+
+			// 验证响应体被透传（不做格式转换）
+			processedResponseBody := host.GetResponseBody()
+			require.NotNil(t, processedResponseBody)
+
+			responseStr := string(processedResponseBody)
+			// 响应应该保持原生 Vertex 格式
+			require.Contains(t, responseStr, "candidates", "Response should keep native vertex format with candidates")
+			require.Contains(t, responseStr, "usageMetadata", "Response should keep native vertex format with usageMetadata")
+		})
+	})
+}