fix: record zero OpenAI usage logs

backend/internal/service/openai_compat_model_test.go

@@ -336,7 +336,9 @@ func TestForwardAsAnthropic_TerminalUsageWithoutUpstreamCloseReturns(t *testing.
 
 	upstreamBody := []byte(`data: {"type":"response.completed","response":{"id":"resp_1","object":"response","model":"gpt-5.4","status":"completed","output":[{"type":"message","id":"msg_1","role":"assistant","status":"completed","content":[{"type":"output_text","text":"ok"}]}],"usage":{"input_tokens":15,"output_tokens":6,"total_tokens":21,"input_tokens_details":{"cached_tokens":5}}}}` + "\n\n")
 	upstreamStream := newOpenAICompatBlockingReadCloser(upstreamBody)
-	defer upstreamStream.Close()
+	defer func() {
+		require.NoError(t, upstreamStream.Close())
+	}()
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
 		Header:     http.Header{"Content-Type": []string{"text/event-stream"}, "x-request-id": []string{"rid_terminal_no_close"}},
@@ -389,7 +391,9 @@ func TestForwardAsAnthropic_BufferedTerminalWithoutUpstreamCloseReturns(t *testi
 
 	upstreamBody := []byte(`data: {"type":"response.completed","response":{"id":"resp_1","object":"response","model":"gpt-5.4","status":"completed","output":[{"type":"message","id":"msg_1","role":"assistant","status":"completed","content":[{"type":"output_text","text":"ok"}]}],"usage":{"input_tokens":15,"output_tokens":6,"total_tokens":21,"input_tokens_details":{"cached_tokens":5}}}}` + "\n\n")
 	upstreamStream := newOpenAICompatBlockingReadCloser(upstreamBody)
-	defer upstreamStream.Close()
+	defer func() {
+		require.NoError(t, upstreamStream.Close())
+	}()
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
 		Header:     http.Header{"Content-Type": []string{"text/event-stream"}, "x-request-id": []string{"rid_buffered_terminal_no_close"}},

backend/internal/service/openai_gateway_403_reset_test.go

@@ -20,20 +20,29 @@ func (s *openAI403CounterResetStub) ResetOpenAI403Count(_ context.Context, accou
 	return nil
 }
 
-func TestOpenAIGatewayServiceRecordUsage_ResetsOpenAI403CounterBeforeZeroUsageReturn(t *testing.T) {
+func TestOpenAIGatewayServiceRecordUsage_ResetsOpenAI403CounterForZeroUsage(t *testing.T) {
 	counter := &openAI403CounterResetStub{}
 	rateLimitSvc := NewRateLimitService(nil, nil, nil, nil, nil)
 	rateLimitSvc.SetOpenAI403CounterCache(counter)
 
-	svc := &OpenAIGatewayService{
+	usageRepo := &openAIRecordUsageLogRepoStub{inserted: true}
-		rateLimitService: rateLimitSvc,
+	billingRepo := &openAIRecordUsageBillingRepoStub{result: &UsageBillingApplyResult{Applied: true}}
-	}
+	userRepo := &openAIRecordUsageUserRepoStub{}
+	subRepo := &openAIRecordUsageSubRepoStub{}
+	svc := newOpenAIRecordUsageServiceWithBillingRepoForTest(usageRepo, billingRepo, userRepo, subRepo, nil)
+	svc.rateLimitService = rateLimitSvc
 
 	err := svc.RecordUsage(context.Background(), &OpenAIRecordUsageInput{
-		Result:  &OpenAIForwardResult{},
+		Result: &OpenAIForwardResult{
+			RequestID: "resp_zero_usage_reset_403",
+			Model:     "gpt-5.1",
+		},
+		APIKey:  &APIKey{ID: 1001, Group: &Group{RateMultiplier: 1}},
+		User:    &User{ID: 2001},
 		Account: &Account{ID: 777, Platform: PlatformOpenAI},
 	})
 
 	require.NoError(t, err)
 	require.Equal(t, []int64{777}, counter.resetCalls)
+	require.Equal(t, 1, usageRepo.calls)
 }

backend/internal/service/openai_gateway_chat_completions_test.go

@@ -156,7 +156,9 @@ func TestForwardAsChatCompletions_TerminalUsageWithoutUpstreamCloseReturns(t *te
 
 	upstreamBody := []byte(`data: {"type":"response.completed","response":{"id":"resp_1","object":"response","model":"gpt-5.4","status":"completed","output":[{"type":"message","id":"msg_1","role":"assistant","status":"completed","content":[{"type":"output_text","text":"ok"}]}],"usage":{"input_tokens":17,"output_tokens":8,"total_tokens":25,"input_tokens_details":{"cached_tokens":6}}}}` + "\n\n")
 	upstreamStream := newOpenAICompatBlockingReadCloser(upstreamBody)
-	defer upstreamStream.Close()
+	defer func() {
+		require.NoError(t, upstreamStream.Close())
+	}()
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
 		Header:     http.Header{"Content-Type": []string{"text/event-stream"}, "x-request-id": []string{"rid_chat_terminal_no_close"}},
@@ -209,7 +211,9 @@ func TestForwardAsChatCompletions_BufferedTerminalWithoutUpstreamCloseReturns(t
 
 	upstreamBody := []byte(`data: {"type":"response.completed","response":{"id":"resp_1","object":"response","model":"gpt-5.4","status":"completed","output":[{"type":"message","id":"msg_1","role":"assistant","status":"completed","content":[{"type":"output_text","text":"ok"}]}],"usage":{"input_tokens":17,"output_tokens":8,"total_tokens":25,"input_tokens_details":{"cached_tokens":6}}}}` + "\n\n")
 	upstreamStream := newOpenAICompatBlockingReadCloser(upstreamBody)
-	defer upstreamStream.Close()
+	defer func() {
+		require.NoError(t, upstreamStream.Close())
+	}()
 	upstream := &httpUpstreamRecorder{resp: &http.Response{
 		StatusCode: http.StatusOK,
 		Header:     http.Header{"Content-Type": []string{"text/event-stream"}, "x-request-id": []string{"rid_chat_buffered_terminal_no_close"}},

backend/internal/service/openai_gateway_messages.go

@@ -441,13 +441,13 @@ func (s *OpenAIGatewayService) readOpenAICompatBufferedTerminal(
 				return nil, usage, acc, ev.err
 			}
 
+			if isOpenAICompatDoneSentinelLine(ev.line) {
+				return nil, usage, acc, nil
+			}
 			payload, ok := extractOpenAISSEDataLine(ev.line)
 			if !ok || payload == "" {
 				continue
 			}
-			if strings.TrimSpace(payload) == "[DONE]" {
-				return nil, usage, acc, nil
-			}
 
 			var event apicompat.ResponsesStreamEvent
 			if err := json.Unmarshal([]byte(payload), &event); err != nil {
@@ -640,13 +640,13 @@ func (s *OpenAIGatewayService) handleAnthropicStreamingResponse(
 	if streamInterval <= 0 && keepaliveInterval <= 0 {
 		for scanner.Scan() {
 			line := scanner.Text()
+			if isOpenAICompatDoneSentinelLine(line) {
+				return missingTerminalErr()
+			}
 			payload, ok := extractOpenAISSEDataLine(line)
 			if !ok {
 				continue
 			}
-			if strings.TrimSpace(payload) == "[DONE]" {
-				return missingTerminalErr()
-			}
 			if processDataLine(payload) {
 				return finalizeStream()
 			}
@@ -713,13 +713,13 @@ func (s *OpenAIGatewayService) handleAnthropicStreamingResponse(
 			}
 			lastDataAt = time.Now()
 			line := ev.line
+			if isOpenAICompatDoneSentinelLine(line) {
+				return missingTerminalErr()
+			}
 			payload, ok := extractOpenAISSEDataLine(line)
 			if !ok {
 				continue
 			}
-			if strings.TrimSpace(payload) == "[DONE]" {
-				return missingTerminalErr()
-			}
 			if processDataLine(payload) {
 				return finalizeStream()
 			}

backend/internal/service/openai_gateway_record_usage_test.go

@@ -186,6 +186,56 @@ func max(a, b int) int {
 	return b
 }
 
+func TestOpenAIGatewayServiceRecordUsage_ZeroUsageStillWritesUsageLog(t *testing.T) {
+	usageRepo := &openAIRecordUsageLogRepoStub{inserted: true}
+	billingRepo := &openAIRecordUsageBillingRepoStub{result: &UsageBillingApplyResult{Applied: true}}
+	userRepo := &openAIRecordUsageUserRepoStub{}
+	subRepo := &openAIRecordUsageSubRepoStub{}
+	quotaSvc := &openAIRecordUsageAPIKeyQuotaStub{}
+	svc := newOpenAIRecordUsageServiceWithBillingRepoForTest(usageRepo, billingRepo, userRepo, subRepo, nil)
+
+	err := svc.RecordUsage(context.Background(), &OpenAIRecordUsageInput{
+		Result: &OpenAIForwardResult{
+			RequestID: "resp_zero_usage",
+			Usage:     OpenAIUsage{},
+			Model:     "gpt-5.1",
+			Duration:  time.Second,
+		},
+		APIKey:        &APIKey{ID: 1000, Quota: 100, Group: &Group{RateMultiplier: 1}},
+		User:          &User{ID: 2000},
+		Account:       &Account{ID: 3000, Type: AccountTypeAPIKey},
+		APIKeyService: quotaSvc,
+	})
+
+	require.NoError(t, err)
+	require.Equal(t, 1, billingRepo.calls)
+	require.Equal(t, 1, usageRepo.calls)
+	require.Equal(t, 0, userRepo.deductCalls)
+	require.Equal(t, 0, subRepo.incrementCalls)
+	require.Equal(t, 0, quotaSvc.quotaCalls)
+	require.Equal(t, 0, quotaSvc.rateLimitCalls)
+
+	require.NotNil(t, usageRepo.lastLog)
+	require.Equal(t, "resp_zero_usage", usageRepo.lastLog.RequestID)
+	require.Zero(t, usageRepo.lastLog.InputTokens)
+	require.Zero(t, usageRepo.lastLog.OutputTokens)
+	require.Zero(t, usageRepo.lastLog.CacheCreationTokens)
+	require.Zero(t, usageRepo.lastLog.CacheReadTokens)
+	require.Zero(t, usageRepo.lastLog.ImageOutputTokens)
+	require.Zero(t, usageRepo.lastLog.ImageCount)
+	require.Zero(t, usageRepo.lastLog.InputCost)
+	require.Zero(t, usageRepo.lastLog.OutputCost)
+	require.Zero(t, usageRepo.lastLog.TotalCost)
+	require.Zero(t, usageRepo.lastLog.ActualCost)
+
+	require.NotNil(t, billingRepo.lastCmd)
+	require.Zero(t, billingRepo.lastCmd.BalanceCost)
+	require.Zero(t, billingRepo.lastCmd.SubscriptionCost)
+	require.Zero(t, billingRepo.lastCmd.APIKeyQuotaCost)
+	require.Zero(t, billingRepo.lastCmd.APIKeyRateLimitCost)
+	require.Zero(t, billingRepo.lastCmd.AccountQuotaCost)
+}
+
 func TestOpenAIGatewayServiceRecordUsage_UsesUserSpecificGroupRate(t *testing.T) {
 	groupID := int64(11)
 	groupRate := 1.4

backend/internal/service/openai_gateway_service.go

@@ -5041,13 +5041,6 @@ func (s *OpenAIGatewayService) RecordUsage(ctx context.Context, input *OpenAIRec
 		s.rateLimitService.ResetOpenAI403Counter(ctx, input.Account.ID)
 	}
 
-	// 跳过所有 token 均为零的用量记录——上游未返回 usage 时不应写入数据库
-	if result.Usage.InputTokens == 0 && result.Usage.OutputTokens == 0 &&
-		result.Usage.CacheCreationInputTokens == 0 && result.Usage.CacheReadInputTokens == 0 &&
-		result.Usage.ImageOutputTokens == 0 && result.ImageCount == 0 {
-		return nil
-	}
-
 	apiKey := input.APIKey
 	user := input.User
 	account := input.Account