fix(canvas): 模型生成 - 保留安全的上游失败原因并展示到用户卡片

backend/internal/app/analytics.go

@@ -995,7 +995,7 @@ func (s *Service) enrichAPICallLogFailureSummary(log *model.ApiCallLog, response
 		Body:       string(responseBody),
 	})
 	detail := strings.TrimSpace(log.Error)
-	if detail == "" || detail == userMessage {
+	if detail == "" || detail == userMessage || strings.Contains(userMessage, "；上游："+detail) {
 		log.Error = userMessage
 		return
 	}

backend/internal/app/provider.go

@@ -128,7 +128,7 @@ type providerError struct {
 }
 
 // providerPayloadError 在进程内保留上游原始原因，供协议兼容分支做机器判断；
-// 对调用方只暴露归类后的稳定文案。Provider 正文可能包含密钥或内部诊断，
+// 对调用方只暴露经过过滤的错误原因。Provider 正文可能包含密钥或内部诊断，
 // 禁止原样进入用户错误和日志。
 type providerPayloadError struct {
 	raw     string
@@ -230,6 +230,13 @@ func withProviderRequestKind(ctx context.Context, requestKind string) context.Co
 }
 
 func (e providerHTTPError) Error() string {
+	if e.StatusCode == http.StatusBadRequest || e.StatusCode == http.StatusUnprocessableEntity {
+		return providerErrorWithDetail(e.summary(), e.Body)
+	}
+	return appendProviderErrorDetail(e.summary(), e.Body)
+}
+
+func (e providerHTTPError) summary() string {
 	switch e.StatusCode {
 	case 524:
 		return "上游网关超时（524）：模型请求可能仍在服务端执行并产生费用，请勿立即重试，请先到供应商后台核对任务或账单"
@@ -266,14 +273,6 @@ func providerUserFacingErrorMessage(err error) string {
 	}
 	var httpErr providerHTTPError
 	if errors.As(err, &httpErr) {
-		// 仅对上游参数校验类状态码解析正文。其他状态码的正文可能是网关 HTML、
-		// 鉴权诊断或含密钥的内部信息，归类价值低且更容易误判。
-		switch httpErr.StatusCode {
-		case http.StatusBadRequest, http.StatusUnprocessableEntity:
-			if message, ok := providerPayloadErrorCategory(httpErr.Body); ok {
-				return message
-			}
-		}
 		return httpErr.Error()
 	}
 	return "连接模型服务失败，请检查渠道地址和网络"
@@ -316,10 +315,7 @@ func providerPayloadErrorCategory(raw string) (string, bool) {
 }
 
 func providerPayloadErrorMessage(raw string) string {
-	if message, ok := providerPayloadErrorCategory(raw); ok {
-		return message
-	}
-	return "模型服务返回失败，请检查请求内容或渠道配置"
+	return providerErrorWithDetail("模型服务返回失败，请检查请求内容或渠道配置", raw)
 }
 
 func (s *Service) processCanvasGenerationTask(ctx context.Context, userID string, taskProjectID string, taskType string, fallbackPrompt string, rawInput string) (map[string]interface{}, error) {

backend/internal/app/provider_error_message.go

@@ -0,0 +1,55 @@
+package app
+
+import (
+	"encoding/json"
+	"regexp"
+	"strings"
+)
+
+var providerErrorURL = regexp.MustCompile(`(?i)https?://[^\s<>"'，。；）]+`)
+var providerErrorSensitive = regexp.MustCompile(`(?i)余额|额度|配额|欠费|账单|充值|计费|密钥|密码|令牌|balance|quota|billing|credit|payment|funds|wallet|api[ _-]?key|authorization|bearer|cookie|(?:access|refresh|auth|session)[ _-]?token|token\s*[=:]|secret|password|credential|sk-[a-z0-9]|tenant|trace[ _-]?id|request[ _-]?id|internal stack|stack\s*trace|dial tcp|no such host|prompt\s*[=:]`)
+
+// 只提取错误消息字段，不序列化整个响应，避免回传 headers、请求正文和诊断信息。
+func providerErrorDetail(raw string) string {
+	raw = strings.TrimSpace(raw)
+	var payload any
+	if json.Unmarshal([]byte(raw), &payload) == nil {
+		raw = providerErrorMessageField(payload)
+	} else if strings.HasPrefix(raw, "{") || strings.HasPrefix(raw, "[") {
+		return ""
+	}
+	// 网关 HTML、敏感账务/凭据诊断整条隐藏；普通消息里的 URL 单独移除。
+	if strings.HasPrefix(raw, "{") || strings.HasPrefix(raw, "[") || strings.ContainsAny(raw, "<>") || providerErrorSensitive.MatchString(raw) {
+		return ""
+	}
+	raw = providerErrorURL.ReplaceAllString(raw, "[链接已隐藏]")
+	return truncateRunes(strings.Join(strings.Fields(raw), " "), 1_500)
+}
+
+func providerErrorMessageField(value any) string {
+	switch value := value.(type) {
+	case string:
+		return strings.TrimSpace(value)
+	case map[string]any:
+		for _, key := range []string{"error", "message", "msg", "detail"} {
+			if message := providerErrorMessageField(value[key]); message != "" {
+				return message
+			}
+		}
+	}
+	return ""
+}
+
+func providerErrorWithDetail(fallback, raw string) string {
+	if message, ok := providerPayloadErrorCategory(raw); ok {
+		fallback = message
+	}
+	return appendProviderErrorDetail(fallback, raw)
+}
+
+func appendProviderErrorDetail(fallback, raw string) string {
+	if detail := providerErrorDetail(raw); detail != "" && detail != fallback {
+		return fallback + "；上游：" + detail
+	}
+	return fallback
+}

backend/internal/app/provider_error_message_test.go

@@ -0,0 +1,71 @@
+package app
+
+import (
+	"errors"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestProviderErrorDetail(t *testing.T) {
+	for _, tt := range []struct{ name, raw, want string }{
+		{"moderation", `{"error":{"message":"非常抱歉，生成的图片可能违反了关于裸露、色情或情色内容的防护限制。请重试或修改提示语。"}}`, "非常抱歉，生成的图片可能违反了关于裸露、色情或情色内容的防护限制。请重试或修改提示语。"},
+		{"parameter", `{"message":"size must be 1024x1024","request_id":"private","url":"https://private.test"}`, "size must be 1024x1024"},
+		{"url", `{"error":"请修改图片尺寸 https://private.test/path?q=value"}`, "请修改图片尺寸 [链接已隐藏]"},
+		{"detail", `{"detail":"请上传 PNG 图片"}`, "请上传 PNG 图片"},
+		{"plain", "请缩短提示词", "请缩短提示词"},
+		{"token limit", `{"message":"max_tokens must be less than 4096"}`, "max_tokens must be less than 4096"},
+		{"balance", `{"message":"渠道余额不足，剩余 1.25 元"}`, ""},
+		{"billing", `{"message":"insufficient credits: $0.25"}`, ""},
+		{"key", `{"message":"invalid api_key=private"}`, ""},
+		{"cookie", `{"message":"Cookie: session=private"}`, ""},
+		{"token", `{"message":"access_token=private"}`, ""},
+		{"html", "<html>502 private gateway</html>", ""},
+		{"malformed", `{"message":"partial`, ""},
+		{"diagnostics", `{"request_id":"private","headers":{"Authorization":"private"}}`, ""},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := providerErrorDetail(tt.raw); got != tt.want {
+				t.Fatalf("got %q, want %q", got, tt.want)
+			}
+		})
+	}
+}
+
+func TestTaskFailurePreservesSafeProviderDetail(t *testing.T) {
+	const detail = "非常抱歉，生成的图片可能违反了关于裸露、色情或情色内容的防护限制。请重试或修改提示语。"
+	for _, status := range []int{400, 403, 422, 429, 500, 502} {
+		err := fmt.Errorf("图片生成失败：%w", providerHTTPError{StatusCode: status, Body: `{"error":{"message":"` + detail + `"}}`})
+		if got := taskFailureMessage(err); !strings.Contains(got, "；上游："+detail) {
+			t.Fatalf("status %d lost detail: %s", status, got)
+		}
+	}
+	if got := taskFailureMessage(errors.New(providerPayloadErrorMessage(detail))); !strings.Contains(got, detail) {
+		t.Fatalf("business failure lost detail: %s", got)
+	}
+}
+
+func TestProviderErrorDetailThroughHTTPAndBusinessFailures(t *testing.T) {
+	t.Setenv("CANVAS_ALLOWED_PRIVATE_UPSTREAM_HOSTS", "127.0.0.1")
+	const detail = "生成的图片可能违反了关于裸露、色情或情色内容的防护限制。请修改提示语。"
+	for _, status := range []int{http.StatusBadRequest, http.StatusOK} {
+		server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(status)
+			fmt.Fprintf(w, `{"error":{"message":%q}}`, detail)
+		}))
+		for _, target := range []any{&imageResponse{}, &map[string]interface{}{}} {
+			req, err := http.NewRequest(http.MethodGet, server.URL, nil)
+			if err != nil {
+				t.Fatal(err)
+			}
+			err = doJSON(req, target)
+			if err == nil || !strings.Contains(taskFailureMessage(err), detail) {
+				t.Errorf("status %d target %T lost upstream detail: %v", status, target, err)
+			}
+		}
+		server.Close()
+	}
+}