feat(config): Add max file size threshold and improve path configuration

- Extend PathConfig with MaxSize parameter to define upper file size limit
- Update routing logic to handle both minimum and maximum file size thresholds
- Enhance frontend configuration UI to support max size input
- Improve file routing decision-making with comprehensive size range checks

internal/config/types.go

@@ -12,9 +12,11 @@ type Config struct {
 }
 
 type PathConfig struct {
-	DefaultTarget   string            `json:"DefaultTarget"` // 默认回源地址
-	ExtensionMap    map[string]string `json:"ExtensionMap"`  // 特定后缀的回源地址
-	SizeThreshold   int64             `json:"SizeThreshold"` // 文件大小阈值(字节)，超过此大小才使用ExtensionMap
+	Path            string            `json:"Path"`
+	DefaultTarget   string            `json:"DefaultTarget"`
+	ExtensionMap    map[string]string `json:"ExtensionMap"`
+	SizeThreshold   int64             `json:"SizeThreshold"` // 最小文件大小阈值
+	MaxSize         int64             `json:"MaxSize"`       // 最大文件大小阈值
 	processedExtMap map[string]string // 内部使用，存储拆分后的映射
 }
 

internal/utils/utils.go

@@ -22,10 +22,19 @@ type fileSizeCache struct {
 	timestamp time.Time
 }
 
+// 可访问性缓存项
+type accessibilityCache struct {
+	accessible bool
+	timestamp  time.Time
+}
+
 var (
 	// 文件大小缓存，过期时间5分钟
-	sizeCache    sync.Map
+	sizeCache sync.Map
+	// 可访问性缓存，过期时间30秒
+	accessCache  sync.Map
 	cacheTTL     = 5 * time.Minute
+	accessTTL    = 30 * time.Second
 	maxCacheSize = 10000 // 最大缓存条目数
 )
 
@@ -35,6 +44,7 @@ func init() {
 		ticker := time.NewTicker(time.Minute)
 		for range ticker.C {
 			now := time.Now()
+			// 清理文件大小缓存
 			var items []struct {
 				key       interface{}
 				timestamp time.Time
@@ -59,6 +69,15 @@ func init() {
 					sizeCache.Delete(items[i].key)
 				}
 			}
+
+			// 清理可访问性缓存
+			accessCache.Range(func(key, value interface{}) bool {
+				cache := value.(accessibilityCache)
+				if now.Sub(cache.timestamp) > accessTTL {
+					accessCache.Delete(key)
+				}
+				return true
+			})
 		}
 	}()
 }
@@ -168,10 +187,16 @@ func GetTargetURL(client *http.Client, r *http.Request, pathConfig config.PathCo
 	// 默认使用默认目标
 	targetBase := pathConfig.DefaultTarget
 
-	// 如果没有设置阈值，使用默认值 500KB
-	threshold := pathConfig.SizeThreshold
-	if threshold <= 0 {
-		threshold = 500 * 1024
+	// 如果没有设置最小阈值，使用默认值 500KB
+	minThreshold := pathConfig.SizeThreshold
+	if minThreshold <= 0 {
+		minThreshold = 500 * 1024
+	}
+
+	// 如果没有设置最大阈值，使用默认值 10MB
+	maxThreshold := pathConfig.MaxSize
+	if maxThreshold <= 0 {
+		maxThreshold = 10 * 1024 * 1024
 	}
 
 	// 检查文件扩展名
@@ -181,44 +206,58 @@ func GetTargetURL(client *http.Client, r *http.Request, pathConfig config.PathCo
 			ext = ext[1:] // 移除开头的点
 			// 先检查是否在扩展名映射中
 			if altTarget, exists := pathConfig.GetExtensionTarget(ext); exists {
-				// 先检查扩展名映射的目标是否可访问
-				if isTargetAccessible(client, altTarget+path) {
-					// 检查文件大小
-					contentLength := r.ContentLength
-					if contentLength <= 0 {
-						// 如果无法获取 Content-Length，尝试发送 HEAD 请求到备用源
-						if size, err := GetFileSize(client, altTarget+path); err == nil {
-							contentLength = size
-							log.Printf("[FileSize] Path: %s, Size: %s (from alternative source)",
-								path, FormatBytes(contentLength))
-						} else {
-							log.Printf("[FileSize] Failed to get size from alternative source for %s: %v", path, err)
-							// 如果从备用源获取失败，尝试从默认源获取
-							if size, err := GetFileSize(client, targetBase+path); err == nil {
-								contentLength = size
-								log.Printf("[FileSize] Path: %s, Size: %s (from default source)",
-									path, FormatBytes(contentLength))
-							} else {
-								log.Printf("[FileSize] Failed to get size from default source for %s: %v", path, err)
-							}
-						}
-					} else {
-						log.Printf("[FileSize] Path: %s, Size: %s (from Content-Length)",
-							path, FormatBytes(contentLength))
-					}
+				// 使用 channel 来并发获取文件大小和检查可访问性
+				type result struct {
+					size       int64
+					accessible bool
+					err        error
+				}
+				defaultChan := make(chan result, 1)
+				altChan := make(chan result, 1)
 
-					// 只有当文件大于阈值时才使用扩展名映射的目标
-					if contentLength > threshold {
-						log.Printf("[Route] %s -> %s (size: %s > %s)",
-							path, altTarget, FormatBytes(contentLength), FormatBytes(threshold))
-						targetBase = altTarget
+				// 并发检查默认源和备用源
+				go func() {
+					size, err := GetFileSize(client, targetBase+path)
+					defaultChan <- result{size: size, err: err}
+				}()
+				go func() {
+					accessible := isTargetAccessible(client, altTarget+path)
+					altChan <- result{accessible: accessible}
+				}()
+
+				// 获取默认源结果
+				defaultResult := <-defaultChan
+				if defaultResult.err != nil {
+					log.Printf("[FileSize] Failed to get size from default source for %s: %v", path, defaultResult.err)
+					return targetBase
+				}
+				contentLength := defaultResult.size
+				log.Printf("[FileSize] Path: %s, Size: %s (from default source)",
+					path, FormatBytes(contentLength))
+
+				// 检查文件大小是否在阈值范围内
+				if contentLength > minThreshold && contentLength <= maxThreshold {
+					// 获取备用源检查结果
+					altResult := <-altChan
+					if altResult.accessible {
+						log.Printf("[Route] %s -> %s (size: %s > %s and <= %s)",
+							path, altTarget, FormatBytes(contentLength),
+							FormatBytes(minThreshold), FormatBytes(maxThreshold))
+						return altTarget
 					} else {
-						log.Printf("[Route] %s -> %s (size: %s <= %s)",
-							path, targetBase, FormatBytes(contentLength), FormatBytes(threshold))
+						log.Printf("[Route] %s -> %s (fallback: alternative target not accessible)",
+							path, targetBase)
 					}
+				} else if contentLength <= minThreshold {
+					// 如果文件大小不合适，直接丢弃备用源检查结果
+					go func() { <-altChan }()
+					log.Printf("[Route] %s -> %s (size: %s <= %s)",
+						path, targetBase, FormatBytes(contentLength), FormatBytes(minThreshold))
 				} else {
-					log.Printf("[Route] %s -> %s (fallback: alternative target not accessible)",
-						path, targetBase)
+					// 如果文件大小不合适，直接丢弃备用源检查结果
+					go func() { <-altChan }()
+					log.Printf("[Route] %s -> %s (size: %s > %s)",
+						path, targetBase, FormatBytes(contentLength), FormatBytes(maxThreshold))
 				}
 			} else {
 				// 记录没有匹配扩展名映射的情况
@@ -238,6 +277,15 @@ func GetTargetURL(client *http.Client, r *http.Request, pathConfig config.PathCo
 
 // isTargetAccessible 检查目标URL是否可访问
 func isTargetAccessible(client *http.Client, url string) bool {
+	// 先查缓存
+	if cache, ok := accessCache.Load(url); ok {
+		cacheItem := cache.(accessibilityCache)
+		if time.Since(cacheItem.timestamp) < accessTTL {
+			return cacheItem.accessible
+		}
+		accessCache.Delete(url)
+	}
+
 	req, err := http.NewRequest("HEAD", url, nil)
 	if err != nil {
 		log.Printf("[Check] Failed to create request for %s: %v", url, err)
@@ -255,8 +303,14 @@ func isTargetAccessible(client *http.Client, url string) bool {
 	}
 	defer resp.Body.Close()
 
-	// 检查状态码是否表示成功
-	return resp.StatusCode >= 200 && resp.StatusCode < 400
+	accessible := resp.StatusCode >= 200 && resp.StatusCode < 400
+	// 缓存结果
+	accessCache.Store(url, accessibilityCache{
+		accessible: accessible,
+		timestamp:  time.Now(),
+	})
+
+	return accessible
 }
 
 // SafeInt64 安全地将 interface{} 转换为 int64

web/app/dashboard/config/page.tsx

@@ -40,7 +40,8 @@ import {
 interface PathMapping {
   DefaultTarget: string
   ExtensionMap?: Record<string, string>
-  SizeThreshold?: number
+  SizeThreshold?: number  // 最小文件大小阈值
+  MaxSize?: number       // 最大文件大小阈值
 }
 
 interface FixedPath {
@@ -80,6 +81,7 @@ export default function ConfigPage() {
     defaultTarget: "",
     extensionMap: {} as Record<string, string>,
     sizeThreshold: 0,
+    maxSize: 0,
     sizeUnit: 'MB' as 'B' | 'KB' | 'MB' | 'GB',
   })
   const [fixedPathDialogOpen, setFixedPathDialogOpen] = useState(false)
@@ -98,6 +100,7 @@ export default function ConfigPage() {
     path: string;
     defaultTarget: string;
     sizeThreshold: number;
+    maxSize: number;
     sizeUnit: 'B' | 'KB' | 'MB' | 'GB';
   } | null>(null);
 
@@ -218,6 +221,7 @@ export default function ConfigPage() {
           defaultTarget: "",
           extensionMap: {},
           sizeThreshold: 0,
+          maxSize: 0,
           sizeUnit: 'MB',
         })
       }
@@ -251,10 +255,11 @@ export default function ConfigPage() {
 
   const addOrUpdatePath = () => {
     if (!config) return
-    const data = editingPathData ? editingPathData : newPathData
     
-    // 验证输入
-    if (!data.path.trim() || !data.defaultTarget.trim()) {
+    const data = editingPathData || newPathData
+    const { path, defaultTarget, sizeThreshold, maxSize, sizeUnit } = data
+    
+    if (!path || !defaultTarget) {
       toast({
         title: "错误",
         description: "路径和默认目标不能为空",
@@ -263,66 +268,55 @@ export default function ConfigPage() {
       return
     }
 
-    // 验证路径格式
-    if (!data.path.startsWith('/')) {
+    // 转换大小为字节
+    const sizeThresholdBytes = convertToBytes(sizeThreshold, sizeUnit)
+    const maxSizeBytes = convertToBytes(maxSize, sizeUnit)
+
+    // 验证阈值
+    if (maxSizeBytes > 0 && sizeThresholdBytes >= maxSizeBytes) {
       toast({
         title: "错误",
-        description: "路径必须以/开头",
+        description: "最大文件大小阈值必须大于最小文件大小阈值",
         variant: "destructive",
       })
       return
     }
 
-    // 验证URL格式
-    try {
-      new URL(data.defaultTarget)
-    } catch {
-      toast({
-        title: "错误",
-        description: "默认目标URL格式不正确",
-        variant: "destructive",
-      })
-      return
-    }
-
-    const sizeInBytes = convertToBytes(data.sizeThreshold, data.sizeUnit)
     const newConfig = { ...config }
-    const existingMapping = newConfig.MAP[data.path]
+    const pathConfig: PathMapping = {
+      DefaultTarget: defaultTarget,
+      ExtensionMap: {},
+      SizeThreshold: sizeThresholdBytes,
+      MaxSize: maxSizeBytes
+    }
+
+    // 如果是编辑现有路径，保留原有的扩展名映射
+    if (editingPathData && typeof config.MAP[path] === 'object') {
+      const existingConfig = config.MAP[path] as PathMapping
+      pathConfig.ExtensionMap = existingConfig.ExtensionMap
+    }
+
+    newConfig.MAP[path] = pathConfig
+    setConfig(newConfig)
     
     if (editingPathData) {
-      if (typeof existingMapping === 'object') {
-        newConfig.MAP[data.path] = {
-          DefaultTarget: data.defaultTarget,
-          SizeThreshold: sizeInBytes,
-          ExtensionMap: existingMapping.ExtensionMap || {}
-        }
-      } else {
-        newConfig.MAP[data.path] = {
-          DefaultTarget: data.defaultTarget,
-          SizeThreshold: sizeInBytes
-        }
-      }
+      setEditingPathData(null)
     } else {
-      newConfig.MAP[data.path] = {
-        DefaultTarget: data.defaultTarget,
-        SizeThreshold: sizeInBytes
-      }
+      setNewPathData({
+        path: "",
+        defaultTarget: "",
+        extensionMap: {},
+        sizeThreshold: 0,
+        maxSize: 0,
+        sizeUnit: 'MB',
+      })
     }
     
-    setConfig(newConfig)
     setPathDialogOpen(false)
-    setEditingPathData(null)
-    setNewPathData({
-      path: "",
-      defaultTarget: "",
-      extensionMap: {},
-      sizeThreshold: 0,
-      sizeUnit: 'MB',
-    })
     
     toast({
       title: "成功",
-      description: "路径映射已更新",
+      description: `${editingPathData ? '更新' : '添加'}路径配置成功`,
     })
   }
 
@@ -552,6 +546,7 @@ export default function ConfigPage() {
       defaultTarget: "",
       extensionMap: {},
       sizeThreshold: 0,
+      maxSize: 0,
       sizeUnit: 'MB',
     })
     setPathDialogOpen(true)
@@ -671,15 +666,18 @@ export default function ConfigPage() {
         path,
         defaultTarget: target,
         sizeThreshold: 0,
+        maxSize: 0,
         sizeUnit: 'MB'
       })
     } else {
       const sizeThreshold = target.SizeThreshold || 0
+      const maxSize = target.MaxSize || 0
       const { value, unit } = convertBytesToUnit(sizeThreshold)
       setEditingPathData({
         path,
         defaultTarget: target.DefaultTarget,
         sizeThreshold: value,
+        maxSize: maxSize,
         sizeUnit: unit
       })
     }
@@ -787,43 +785,99 @@ export default function ConfigPage() {
                           默认的回源地址，所有请求都会转发到这个地址
                         </p>
                       </div>
-                      <div className="space-y-2">
-                        <Label>大小阈值</Label>
-                        <div className="flex items-center space-x-2">
-                          <Input
-                            type="number"
-                            value={editingPathData ? editingPathData.sizeThreshold : newPathData.sizeThreshold}
-                            onChange={(e) => {
-                              const value = parseInt(e.target.value) || 0
-                              if (editingPathData) {
-                                setEditingPathData({ ...editingPathData, sizeThreshold: value })
-                              } else {
-                                setNewPathData({ ...newPathData, sizeThreshold: value })
-                              }
-                            }}
-                            min={0}
-                          />
-                          <select
-                            className="h-10 rounded-md border border-input bg-background px-3"
-                            value={editingPathData ? editingPathData.sizeUnit : newPathData.sizeUnit}
-                            onChange={(e) => {
-                              const unit = e.target.value as 'B' | 'KB' | 'MB' | 'GB'
-                              if (editingPathData) {
-                                setEditingPathData({ ...editingPathData, sizeUnit: unit })
-                              } else {
-                                setNewPathData({ ...newPathData, sizeUnit: unit })
-                              }
-                            }}
-                          >
-                            <option value="B">B</option>
-                            <option value="KB">KB</option>
-                            <option value="MB">MB</option>
-                            <option value="GB">GB</option>
-                          </select>
+                      <div className="grid gap-4">
+                        <div className="grid gap-2">
+                          <Label htmlFor="sizeThreshold">最小文件大小阈值</Label>
+                          <div className="flex gap-2">
+                            <Input
+                              id="sizeThreshold"
+                              type="number"
+                              value={editingPathData?.sizeThreshold ?? newPathData.sizeThreshold}
+                              onChange={(e) => {
+                                if (editingPathData) {
+                                  setEditingPathData({
+                                    ...editingPathData,
+                                    sizeThreshold: Number(e.target.value),
+                                  })
+                                } else {
+                                  setNewPathData({
+                                    ...newPathData,
+                                    sizeThreshold: Number(e.target.value),
+                                  })
+                                }
+                              }}
+                            />
+                            <select
+                              className="w-24 rounded-md border border-input bg-background px-3"
+                              value={editingPathData?.sizeUnit ?? newPathData.sizeUnit}
+                              onChange={(e) => {
+                                const unit = e.target.value as 'B' | 'KB' | 'MB' | 'GB'
+                                if (editingPathData) {
+                                  setEditingPathData({
+                                    ...editingPathData,
+                                    sizeUnit: unit,
+                                  })
+                                } else {
+                                  setNewPathData({
+                                    ...newPathData,
+                                    sizeUnit: unit,
+                                  })
+                                }
+                              }}
+                            >
+                              <option value="B">B</option>
+                              <option value="KB">KB</option>
+                              <option value="MB">MB</option>
+                              <option value="GB">GB</option>
+                            </select>
+                          </div>
+                        </div>
+                        <div className="grid gap-2">
+                          <Label htmlFor="maxSize">最大文件大小阈值</Label>
+                          <div className="flex gap-2">
+                            <Input
+                              id="maxSize"
+                              type="number"
+                              value={editingPathData?.maxSize ?? newPathData.maxSize}
+                              onChange={(e) => {
+                                if (editingPathData) {
+                                  setEditingPathData({
+                                    ...editingPathData,
+                                    maxSize: Number(e.target.value),
+                                  })
+                                } else {
+                                  setNewPathData({
+                                    ...newPathData,
+                                    maxSize: Number(e.target.value),
+                                  })
+                                }
+                              }}
+                            />
+                            <select
+                              className="w-24 rounded-md border border-input bg-background px-3"
+                              value={editingPathData?.sizeUnit ?? newPathData.sizeUnit}
+                              onChange={(e) => {
+                                const unit = e.target.value as 'B' | 'KB' | 'MB' | 'GB'
+                                if (editingPathData) {
+                                  setEditingPathData({
+                                    ...editingPathData,
+                                    sizeUnit: unit,
+                                  })
+                                } else {
+                                  setNewPathData({
+                                    ...newPathData,
+                                    sizeUnit: unit,
+                                  })
+                                }
+                              }}
+                            >
+                              <option value="B">B</option>
+                              <option value="KB">KB</option>
+                              <option value="MB">MB</option>
+                              <option value="GB">GB</option>
+                            </select>
+                          </div>
                         </div>
-                        <p className="text-sm text-muted-foreground">
-                          文件大小超过此阈值时，将使用扩展名映射中的目标地址（如果存在）
-                        </p>
                       </div>
                       <Button onClick={addOrUpdatePath}>
                         {editingPathData ? "保存" : "添加"}