fix: 修复 golangci-lint 检查错误

- SA1029: 创建 ctxkey 包定义类型安全的 context key
- ST1005: 错误字符串首字母改小写
- errcheck: 显式忽略 bytes.Buffer.Write 返回值
- 修复单元测试中 GatewayService 缺少 cfg 字段的问题

backend/internal/pkg/antigravity/client.go

@@ -114,7 +114,7 @@ func (c *Client) ExchangeCode(ctx context.Context, code, codeVerifier string) (*
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {
-		return nil, fmt.Errorf("Token 交换请求失败: %w", err)
+		return nil, fmt.Errorf("token 交换请求失败: %w", err)
 	}
 	defer func() { _ = resp.Body.Close() }()
 
@@ -124,12 +124,12 @@ func (c *Client) ExchangeCode(ctx context.Context, code, codeVerifier string) (*
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("Token 交换失败 (HTTP %d): %s", resp.StatusCode, string(bodyBytes))
+		return nil, fmt.Errorf("token 交换失败 (HTTP %d): %s", resp.StatusCode, string(bodyBytes))
 	}
 
 	var tokenResp TokenResponse
 	if err := json.Unmarshal(bodyBytes, &tokenResp); err != nil {
-		return nil, fmt.Errorf("Token 解析失败: %w", err)
+		return nil, fmt.Errorf("token 解析失败: %w", err)
 	}
 
 	return &tokenResp, nil
@@ -151,7 +151,7 @@ func (c *Client) RefreshToken(ctx context.Context, refreshToken string) (*TokenR
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {
-		return nil, fmt.Errorf("Token 刷新请求失败: %w", err)
+		return nil, fmt.Errorf("token 刷新请求失败: %w", err)
 	}
 	defer func() { _ = resp.Body.Close() }()
 
@@ -161,12 +161,12 @@ func (c *Client) RefreshToken(ctx context.Context, refreshToken string) (*TokenR
 	}
 
 	if resp.StatusCode != http.StatusOK {
-		return nil, fmt.Errorf("Token 刷新失败 (HTTP %d): %s", resp.StatusCode, string(bodyBytes))
+		return nil, fmt.Errorf("token 刷新失败 (HTTP %d): %s", resp.StatusCode, string(bodyBytes))
 	}
 
 	var tokenResp TokenResponse
 	if err := json.Unmarshal(bodyBytes, &tokenResp); err != nil {
-		return nil, fmt.Errorf("Token 解析失败: %w", err)
+		return nil, fmt.Errorf("token 解析失败: %w", err)
 	}
 
 	return &tokenResp, nil

backend/internal/pkg/antigravity/gemini_types.go

@@ -14,13 +14,13 @@ type V1InternalRequest struct {
 
 // GeminiRequest Gemini 请求内容
 type GeminiRequest struct {
-	Contents          []GeminiContent          `json:"contents"`
+	Contents          []GeminiContent         `json:"contents"`
-	SystemInstruction *GeminiContent           `json:"systemInstruction,omitempty"`
+	SystemInstruction *GeminiContent          `json:"systemInstruction,omitempty"`
-	GenerationConfig  *GeminiGenerationConfig  `json:"generationConfig,omitempty"`
+	GenerationConfig  *GeminiGenerationConfig `json:"generationConfig,omitempty"`
-	Tools             []GeminiToolDeclaration  `json:"tools,omitempty"`
+	Tools             []GeminiToolDeclaration `json:"tools,omitempty"`
-	ToolConfig        *GeminiToolConfig        `json:"toolConfig,omitempty"`
+	ToolConfig        *GeminiToolConfig       `json:"toolConfig,omitempty"`
-	SafetySettings    []GeminiSafetySetting    `json:"safetySettings,omitempty"`
+	SafetySettings    []GeminiSafetySetting   `json:"safetySettings,omitempty"`
-	SessionID         string                   `json:"sessionId,omitempty"`
+	SessionID         string                  `json:"sessionId,omitempty"`
 }
 
 // GeminiContent Gemini 内容
@@ -31,10 +31,10 @@ type GeminiContent struct {
 
 // GeminiPart Gemini 内容部分
 type GeminiPart struct {
-	Text             string            `json:"text,omitempty"`
+	Text             string                  `json:"text,omitempty"`
-	Thought          bool              `json:"thought,omitempty"`
+	Thought          bool                    `json:"thought,omitempty"`
-	ThoughtSignature string            `json:"thoughtSignature,omitempty"`
+	ThoughtSignature string                  `json:"thoughtSignature,omitempty"`
-	InlineData       *GeminiInlineData `json:"inlineData,omitempty"`
+	InlineData       *GeminiInlineData       `json:"inlineData,omitempty"`
 	FunctionCall     *GeminiFunctionCall     `json:"functionCall,omitempty"`
 	FunctionResponse *GeminiFunctionResponse `json:"functionResponse,omitempty"`
 }
@@ -61,12 +61,12 @@ type GeminiFunctionResponse struct {
 
 // GeminiGenerationConfig Gemini 生成配置
 type GeminiGenerationConfig struct {
-	MaxOutputTokens int                      `json:"maxOutputTokens,omitempty"`
+	MaxOutputTokens int                   `json:"maxOutputTokens,omitempty"`
-	Temperature     *float64                 `json:"temperature,omitempty"`
+	Temperature     *float64              `json:"temperature,omitempty"`
-	TopP            *float64                 `json:"topP,omitempty"`
+	TopP            *float64              `json:"topP,omitempty"`
-	TopK            *int                     `json:"topK,omitempty"`
+	TopK            *int                  `json:"topK,omitempty"`
-	ThinkingConfig  *GeminiThinkingConfig    `json:"thinkingConfig,omitempty"`
+	ThinkingConfig  *GeminiThinkingConfig `json:"thinkingConfig,omitempty"`
-	StopSequences   []string                 `json:"stopSequences,omitempty"`
+	StopSequences   []string              `json:"stopSequences,omitempty"`
 }
 
 // GeminiThinkingConfig Gemini thinking 配置

backend/internal/pkg/antigravity/stream_transformer.go

@@ -72,7 +72,7 @@ func (p *StreamingProcessor) ProcessLine(line string) []byte {
 
 	// 发送 message_start
 	if !p.messageStartSent {
-		result.Write(p.emitMessageStart(&v1Resp))
+		_, _ = result.Write(p.emitMessageStart(&v1Resp))
 	}
 
 	// 更新 usage
@@ -84,7 +84,7 @@ func (p *StreamingProcessor) ProcessLine(line string) []byte {
 	// 处理 parts
 	if len(geminiResp.Candidates) > 0 && geminiResp.Candidates[0].Content != nil {
 		for _, part := range geminiResp.Candidates[0].Content.Parts {
-			result.Write(p.processPart(&part))
+			_, _ = result.Write(p.processPart(&part))
 		}
 	}
 
@@ -92,7 +92,7 @@ func (p *StreamingProcessor) ProcessLine(line string) []byte {
 	if len(geminiResp.Candidates) > 0 {
 		finishReason := geminiResp.Candidates[0].FinishReason
 		if finishReason != "" {
-			result.Write(p.emitFinish(finishReason))
+			_, _ = result.Write(p.emitFinish(finishReason))
 		}
 	}
 
@@ -104,7 +104,7 @@ func (p *StreamingProcessor) Finish() ([]byte, *ClaudeUsage) {
 	var result bytes.Buffer
 
 	if !p.messageStopSent {
-		result.Write(p.emitFinish(""))
+		_, _ = result.Write(p.emitFinish(""))
 	}
 
 	usage := &ClaudeUsage{
@@ -164,21 +164,21 @@ func (p *StreamingProcessor) processPart(part *GeminiPart) []byte {
 	if part.FunctionCall != nil {
 		// 先处理 trailingSignature
 		if p.trailingSignature != "" {
-			result.Write(p.endBlock())
+			_, _ = result.Write(p.endBlock())
-			result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
+			_, _ = result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
 			p.trailingSignature = ""
 		}
 
-		result.Write(p.processFunctionCall(part.FunctionCall, signature))
+		_, _ = result.Write(p.processFunctionCall(part.FunctionCall, signature))
 		return result.Bytes()
 	}
 
 	// 2. Text 处理
 	if part.Text != "" || part.Thought {
 		if part.Thought {
-			result.Write(p.processThinking(part.Text, signature))
+			_, _ = result.Write(p.processThinking(part.Text, signature))
 		} else {
-			result.Write(p.processText(part.Text, signature))
+			_, _ = result.Write(p.processText(part.Text, signature))
 		}
 	}
 
@@ -186,7 +186,7 @@ func (p *StreamingProcessor) processPart(part *GeminiPart) []byte {
 	if part.InlineData != nil && part.InlineData.Data != "" {
 		markdownImg := fmt.Sprintf("![image](data:%s;base64,%s)",
 			part.InlineData.MimeType, part.InlineData.Data)
-		result.Write(p.processText(markdownImg, ""))
+		_, _ = result.Write(p.processText(markdownImg, ""))
 	}
 
 	return result.Bytes()
@@ -198,21 +198,21 @@ func (p *StreamingProcessor) processThinking(text, signature string) []byte {
 
 	// 处理之前的 trailingSignature
 	if p.trailingSignature != "" {
-		result.Write(p.endBlock())
+		_, _ = result.Write(p.endBlock())
-		result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
+		_, _ = result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
 		p.trailingSignature = ""
 	}
 
 	// 开始或继续 thinking 块
 	if p.blockType != BlockTypeThinking {
-		result.Write(p.startBlock(BlockTypeThinking, map[string]interface{}{
+		_, _ = result.Write(p.startBlock(BlockTypeThinking, map[string]interface{}{
 			"type":     "thinking",
 			"thinking": "",
 		}))
 	}
 
 	if text != "" {
-		result.Write(p.emitDelta("thinking_delta", map[string]interface{}{
+		_, _ = result.Write(p.emitDelta("thinking_delta", map[string]interface{}{
 			"thinking": text,
 		}))
 	}
@@ -239,34 +239,34 @@ func (p *StreamingProcessor) processText(text, signature string) []byte {
 
 	// 处理之前的 trailingSignature
 	if p.trailingSignature != "" {
-		result.Write(p.endBlock())
+		_, _ = result.Write(p.endBlock())
-		result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
+		_, _ = result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
 		p.trailingSignature = ""
 	}
 
 	// 非空 text 带签名 - 特殊处理
 	if signature != "" {
-		result.Write(p.startBlock(BlockTypeText, map[string]interface{}{
+		_, _ = result.Write(p.startBlock(BlockTypeText, map[string]interface{}{
 			"type": "text",
 			"text": "",
 		}))
-		result.Write(p.emitDelta("text_delta", map[string]interface{}{
+		_, _ = result.Write(p.emitDelta("text_delta", map[string]interface{}{
 			"text": text,
 		}))
-		result.Write(p.endBlock())
+		_, _ = result.Write(p.endBlock())
-		result.Write(p.emitEmptyThinkingWithSignature(signature))
+		_, _ = result.Write(p.emitEmptyThinkingWithSignature(signature))
 		return result.Bytes()
 	}
 
 	// 普通 text (无签名)
 	if p.blockType != BlockTypeText {
-		result.Write(p.startBlock(BlockTypeText, map[string]interface{}{
+		_, _ = result.Write(p.startBlock(BlockTypeText, map[string]interface{}{
 			"type": "text",
 			"text": "",
 		}))
 	}
 
-	result.Write(p.emitDelta("text_delta", map[string]interface{}{
+	_, _ = result.Write(p.emitDelta("text_delta", map[string]interface{}{
 		"text": text,
 	}))
 
@@ -295,17 +295,17 @@ func (p *StreamingProcessor) processFunctionCall(fc *GeminiFunctionCall, signatu
 		toolUse["signature"] = signature
 	}
 
-	result.Write(p.startBlock(BlockTypeFunction, toolUse))
+	_, _ = result.Write(p.startBlock(BlockTypeFunction, toolUse))
 
 	// 发送 input_json_delta
 	if fc.Args != nil {
 		argsJSON, _ := json.Marshal(fc.Args)
-		result.Write(p.emitDelta("input_json_delta", map[string]interface{}{
+		_, _ = result.Write(p.emitDelta("input_json_delta", map[string]interface{}{
 			"partial_json": string(argsJSON),
 		}))
 	}
 
-	result.Write(p.endBlock())
+	_, _ = result.Write(p.endBlock())
 
 	return result.Bytes()
 }
@@ -315,7 +315,7 @@ func (p *StreamingProcessor) startBlock(blockType BlockType, contentBlock map[st
 	var result bytes.Buffer
 
 	if p.blockType != BlockTypeNone {
-		result.Write(p.endBlock())
+		_, _ = result.Write(p.endBlock())
 	}
 
 	event := map[string]interface{}{
@@ -324,7 +324,7 @@ func (p *StreamingProcessor) startBlock(blockType BlockType, contentBlock map[st
 		"content_block": contentBlock,
 	}
 
-	result.Write(p.formatSSE("content_block_start", event))
+	_, _ = result.Write(p.formatSSE("content_block_start", event))
 	p.blockType = blockType
 
 	return result.Bytes()
@@ -340,7 +340,7 @@ func (p *StreamingProcessor) endBlock() []byte {
 
 	// Thinking 块结束时发送暂存的签名
 	if p.blockType == BlockTypeThinking && p.pendingSignature != "" {
-		result.Write(p.emitDelta("signature_delta", map[string]interface{}{
+		_, _ = result.Write(p.emitDelta("signature_delta", map[string]interface{}{
 			"signature": p.pendingSignature,
 		}))
 		p.pendingSignature = ""
@@ -351,7 +351,7 @@ func (p *StreamingProcessor) endBlock() []byte {
 		"index": p.blockIndex,
 	}
 
-	result.Write(p.formatSSE("content_block_stop", event))
+	_, _ = result.Write(p.formatSSE("content_block_stop", event))
 
 	p.blockIndex++
 	p.blockType = BlockTypeNone
@@ -381,17 +381,17 @@ func (p *StreamingProcessor) emitDelta(deltaType string, deltaContent map[string
 func (p *StreamingProcessor) emitEmptyThinkingWithSignature(signature string) []byte {
 	var result bytes.Buffer
 
-	result.Write(p.startBlock(BlockTypeThinking, map[string]interface{}{
+	_, _ = result.Write(p.startBlock(BlockTypeThinking, map[string]interface{}{
 		"type":     "thinking",
 		"thinking": "",
 	}))
-	result.Write(p.emitDelta("thinking_delta", map[string]interface{}{
+	_, _ = result.Write(p.emitDelta("thinking_delta", map[string]interface{}{
 		"thinking": "",
 	}))
-	result.Write(p.emitDelta("signature_delta", map[string]interface{}{
+	_, _ = result.Write(p.emitDelta("signature_delta", map[string]interface{}{
 		"signature": signature,
 	}))
-	result.Write(p.endBlock())
+	_, _ = result.Write(p.endBlock())
 
 	return result.Bytes()
 }
@@ -401,11 +401,11 @@ func (p *StreamingProcessor) emitFinish(finishReason string) []byte {
 	var result bytes.Buffer
 
 	// 关闭最后一个块
-	result.Write(p.endBlock())
+	_, _ = result.Write(p.endBlock())
 
 	// 处理 trailingSignature
 	if p.trailingSignature != "" {
-		result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
+		_, _ = result.Write(p.emitEmptyThinkingWithSignature(p.trailingSignature))
 		p.trailingSignature = ""
 	}
 
@@ -431,13 +431,13 @@ func (p *StreamingProcessor) emitFinish(finishReason string) []byte {
 		"usage": usage,
 	}
 
-	result.Write(p.formatSSE("message_delta", deltaEvent))
+	_, _ = result.Write(p.formatSSE("message_delta", deltaEvent))
 
 	if !p.messageStopSent {
 		stopEvent := map[string]interface{}{
 			"type": "message_stop",
 		}
-		result.Write(p.formatSSE("message_stop", stopEvent))
+		_, _ = result.Write(p.formatSSE("message_stop", stopEvent))
 		p.messageStopSent = true
 	}
 

backend/internal/pkg/ctxkey/ctxkey.go

@@ -0,0 +1,10 @@
+// Package ctxkey 定义用于 context.Value 的类型安全 key
+package ctxkey
+
+// Key 定义 context key 的类型，避免使用内置 string 类型（staticcheck SA1029）
+type Key string
+
+const (
+	// ForcePlatform 强制平台（用于 /antigravity 路由），由 middleware.ForcePlatform 设置
+	ForcePlatform Key = "ctx_force_platform"
+)

backend/internal/server/middleware/middleware.go

@@ -3,6 +3,7 @@ package middleware
 import (
 	"context"
 
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	"github.com/gin-gonic/gin"
 )
 
@@ -22,16 +23,12 @@ const (
 	ContextKeyForcePlatform ContextKey = "force_platform"
 )
 
-// ctxKeyForcePlatformStr 用于 request.Context 的字符串 key（供 Service 读取）
-// 注意：service 包中也需要使用相同的字符串 "ctx_force_platform"
-const ctxKeyForcePlatformStr = "ctx_force_platform"
-
 // ForcePlatform 返回设置强制平台的中间件
 // 同时设置 request.Context（供 Service 使用）和 gin.Context（供 Handler 快速检查）
 func ForcePlatform(platform string) gin.HandlerFunc {
 	return func(c *gin.Context) {
-		// 设置到 request.Context，使用字符串 key 供 Service 层读取
+		// 设置到 request.Context，使用 ctxkey.ForcePlatform 供 Service 层读取
-		ctx := context.WithValue(c.Request.Context(), ctxKeyForcePlatformStr, platform)
+		ctx := context.WithValue(c.Request.Context(), ctxkey.ForcePlatform, platform)
 		c.Request = c.Request.WithContext(ctx)
 		// 同时设置到 gin.Context，供 Handler 快速检查
 		c.Set(string(ContextKeyForcePlatform), platform)

backend/internal/service/antigravity_oauth_service.go

@@ -116,7 +116,7 @@ func (s *AntigravityOAuthService) ExchangeCode(ctx context.Context, input *Antig
 	// 交换 token
 	tokenResp, err := client.ExchangeCode(ctx, input.Code, session.CodeVerifier)
 	if err != nil {
-		return nil, fmt.Errorf("Token 交换失败: %w", err)
+		return nil, fmt.Errorf("token 交换失败: %w", err)
 	}
 
 	// 删除 session
@@ -184,7 +184,7 @@ func (s *AntigravityOAuthService) RefreshToken(ctx context.Context, refreshToken
 		lastErr = err
 	}
 
-	return nil, fmt.Errorf("Token 刷新失败 (重试后): %w", lastErr)
+	return nil, fmt.Errorf("token 刷新失败 (重试后): %w", lastErr)
 }
 
 func isNonRetryableAntigravityOAuthError(err error) bool {

backend/internal/service/gateway_multiplatform_test.go

@@ -8,10 +8,16 @@ import (
 	"testing"
 	"time"
 
+	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/pagination"
 	"github.com/stretchr/testify/require"
 )
 
+// testConfig 返回一个用于测试的默认配置
+func testConfig() *config.Config {
+	return &config.Config{RunMode: config.RunModeStandard}
+}
+
 // mockAccountRepoForPlatform 单平台测试用的 mock
 type mockAccountRepoForPlatform struct {
 	accounts          []Account
@@ -177,6 +183,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_Anthropic(t *testing.T
 	svc := &GatewayService{
 		accountRepo: repo,
 		cache:       cache,
+		cfg:         testConfig(),
 	}
 
 	acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -206,6 +213,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_Antigravity(t *testing
 	svc := &GatewayService{
 		accountRepo: repo,
 		cache:       cache,
+		cfg:         testConfig(),
 	}
 
 	acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAntigravity)
@@ -236,6 +244,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_PriorityAndLastUsed(t
 	svc := &GatewayService{
 		accountRepo: repo,
 		cache:       cache,
+		cfg:         testConfig(),
 	}
 
 	acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -258,6 +267,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_NoAvailableAccounts(t
 	svc := &GatewayService{
 		accountRepo: repo,
 		cache:       cache,
+		cfg:         testConfig(),
 	}
 
 	acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -286,6 +296,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_AllExcluded(t *testing
 	svc := &GatewayService{
 		accountRepo: repo,
 		cache:       cache,
+		cfg:         testConfig(),
 	}
 
 	excludedIDs := map[int64]struct{}{1: {}, 2: {}}
@@ -361,6 +372,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_Schedulability(t *test
 			svc := &GatewayService{
 				accountRepo: repo,
 				cache:       cache,
+				cfg:         testConfig(),
 			}
 
 			acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -394,6 +406,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_StickySession(t *testi
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "session-123", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -421,6 +434,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_StickySession(t *testi
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		// 请求 anthropic 平台，但粘性会话绑定的是 antigravity 账户
@@ -450,6 +464,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_StickySession(t *testi
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		excludedIDs := map[int64]struct{}{1: {}}
@@ -478,6 +493,7 @@ func TestGatewayService_SelectAccountForModelWithPlatform_StickySession(t *testi
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountForModelWithPlatform(ctx, nil, "session-123", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -569,6 +585,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -594,6 +611,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -622,6 +640,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "session-123", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -649,6 +668,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "session-123", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -673,6 +693,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)
@@ -698,6 +719,7 @@ func TestGatewayService_selectAccountWithMixedScheduling(t *testing.T) {
 		svc := &GatewayService{
 			accountRepo: repo,
 			cache:       cache,
+			cfg:         testConfig(),
 		}
 
 		acc, err := svc.selectAccountWithMixedScheduling(ctx, nil, "", "claude-3-5-sonnet-20241022", nil, PlatformAnthropic)

backend/internal/service/gateway_service.go

@@ -18,6 +18,7 @@ import (
 
 	"github.com/Wei-Shaw/sub2api/internal/config"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/claude"
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	"github.com/tidwall/gjson"
 	"github.com/tidwall/sjson"
 
@@ -30,9 +31,6 @@ const (
 	stickySessionTTL        = time.Hour // 粘性会话TTL
 )
 
-// ctxKeyForcePlatform 用于从 context 读取强制平台（由 middleware.ForcePlatform 设置）
-// 必须与 middleware.ctxKeyForcePlatformStr 使用相同的字符串值
-const ctxKeyForcePlatform = "ctx_force_platform"
 
 // sseDataRe matches SSE data lines with optional whitespace after colon.
 // Some upstream APIs return non-standard "data:" without space (should be "data: ").
@@ -300,7 +298,7 @@ func (s *GatewayService) SelectAccountForModel(ctx context.Context, groupID *int
 func (s *GatewayService) SelectAccountForModelWithExclusions(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}) (*Account, error) {
 	// 优先检查 context 中的强制平台（/antigravity 路由）
 	var platform string
-	forcePlatform, hasForcePlatform := ctx.Value(ctxKeyForcePlatform).(string)
+	forcePlatform, hasForcePlatform := ctx.Value(ctxkey.ForcePlatform).(string)
 	if hasForcePlatform && forcePlatform != "" {
 		platform = forcePlatform
 	} else if groupID != nil {

backend/internal/service/gemini_messages_compat_service.go

@@ -18,6 +18,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/Wei-Shaw/sub2api/internal/pkg/ctxkey"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/geminicli"
 	"github.com/Wei-Shaw/sub2api/internal/pkg/googleapi"
 
@@ -74,7 +75,7 @@ func (s *GeminiMessagesCompatService) SelectAccountForModel(ctx context.Context,
 func (s *GeminiMessagesCompatService) SelectAccountForModelWithExclusions(ctx context.Context, groupID *int64, sessionHash string, requestedModel string, excludedIDs map[int64]struct{}) (*Account, error) {
 	// 优先检查 context 中的强制平台（/antigravity 路由）
 	var platform string
-	forcePlatform, hasForcePlatform := ctx.Value(ctxKeyForcePlatform).(string)
+	forcePlatform, hasForcePlatform := ctx.Value(ctxkey.ForcePlatform).(string)
 	if hasForcePlatform && forcePlatform != "" {
 		platform = forcePlatform
 	} else if groupID != nil {