图片压缩调用缓存

AGENTS.md

@@ -18,6 +18,13 @@
 - 所有 HTTP 路由仅在 `internal/router/router.go` 中注册。
 - 当 API Handler 发生变化时，更新 Swagger 文档（运行 `make swagger`）。
 - 在提交更改前运行 `make code-check`。
+- 需要缓存或文件管理能力时，必须复用现有平台实现，禁止在业务包中自行创建缓存目录、直接管理缓存文件或重复封装存储后端。
+
+## 缓存与文件能力
+
+- `internal/diskcache`：通过 `diskcache.GetGlobalCache()` 提供字节缓存读写、TTL、最大空间限制、LRU 淘汰、清空、状态统计和配置热更新。
+- `internal/storage`：提供 S3 兼容对象上传、读取、删除、CDN/代理读取及远端文件本地缓存。
+- `internal/apps/upload`：提供上传记录、文件访问控制、本地/S3 文件响应、下载及图片 WebP 压缩；业务应复用这些入口，不直接操作底层文件。
 
 ## 常用命令
 

internal/apps/upload/constants.go

@@ -8,6 +8,4 @@ const (
 	detectContentBytes = 512              // http.DetectContentType 需要的最小字节数
 	uploadDirPerm      = 0755             // 上传目录权限
 	uploadFilePerm     = 0644             // 上传文件权限
-	cacheDirPerm       = 0750             // 缓存目录权限 (gosec)
-	cacheFilePerm      = 0600             // 缓存文件权限 (gosec)
 )

internal/apps/upload/file_server.go

@@ -13,13 +13,13 @@ import (
 	"io"
 	"net/http"
 	"os"
-	"path/filepath"
 	"strconv"
 	"strings"
 
 	"github.com/Rain-kl/Wavelet/internal/apps/oauth"
 	"github.com/Rain-kl/Wavelet/internal/common"
 	"github.com/Rain-kl/Wavelet/internal/db"
+	"github.com/Rain-kl/Wavelet/internal/diskcache"
 	"github.com/Rain-kl/Wavelet/internal/logger"
 	"github.com/Rain-kl/Wavelet/internal/model"
 	"github.com/Rain-kl/Wavelet/internal/storage"
@@ -103,14 +103,13 @@ func ServeUpload(c *gin.Context, upload *model.Upload) {
 		level = "high"
 	}
 
-	// Local cache path for the compressed webp image
-	cachePath := filepath.Join("uploads", "cache", fmt.Sprintf("compressed_%d_%s.webp", upload.ID, level))
-
-	// Check if the compressed file already exists in cache
-	if _, err := os.Stat(cachePath); err == nil {
-		c.Header("Content-Type", "image/webp")
-		c.File(cachePath)
+	cache := diskcache.GetGlobalCache()
+	cacheKey := imageCompressionCacheKey(upload, level)
+	if webpBytes, err := cache.Get(cacheKey); err == nil {
+		c.Data(http.StatusOK, "image/webp", webpBytes)
 		return
+	} else if !errors.Is(err, diskcache.ErrCacheMiss) {
+		logger.WarnF(c.Request.Context(), "failed to read compressed image cache: %v", err)
 	}
 
 	// Cache miss: retrieve original file content
@@ -129,18 +128,25 @@ func ServeUpload(c *gin.Context, upload *model.Upload) {
 		return
 	}
 
-	// Ensure cache directory exists and write cached file
-	if err := os.MkdirAll(filepath.Dir(cachePath), cacheDirPerm); err != nil {
-		logger.ErrorF(c.Request.Context(), "failed to create cache directory: %v", err)
-	} else if err := os.WriteFile(cachePath, webpBytes, cacheFilePerm); err != nil {
-		logger.ErrorF(c.Request.Context(), "failed to write compressed cache file: %v", err)
+	if err := cache.Set(cacheKey, webpBytes, 0); err != nil {
+		logger.WarnF(c.Request.Context(), "failed to cache compressed image: %v", err)
 	}
 
 	// Serve compressed WebP
-	c.Header("Content-Type", "image/webp")
 	c.Data(http.StatusOK, "image/webp", webpBytes)
 }
 
+func imageCompressionCacheKey(upload *model.Upload, level string) string {
+	return fmt.Sprintf(
+		"upload_webp_v1_%d_%d_%d_%s_%s",
+		upload.ID,
+		upload.UpdatedAt.UnixNano(),
+		upload.FileSize,
+		upload.Hash,
+		level,
+	)
+}
+
 // serveOriginal 原始文件的流式响应逻辑
 func serveOriginal(c *gin.Context, upload *model.Upload) {
 	if upload.StorageDriver == "local" || (upload.StorageDriver == "" && !storage.IsEnabled()) {

internal/apps/upload/file_server_test.go

@@ -13,10 +13,10 @@ import (
 	"net/http"
 	"net/http/httptest"
 	"os"
-	"path/filepath"
 	"testing"
 
 	"github.com/Rain-kl/Wavelet/internal/common"
+	"github.com/Rain-kl/Wavelet/internal/diskcache"
 	"github.com/Rain-kl/Wavelet/internal/model"
 	"github.com/Rain-kl/Wavelet/internal/testhelper"
 	"github.com/gin-contrib/sessions"
@@ -205,10 +205,20 @@ func TestImageCompression(t *testing.T) {
 	dbConn, _, cleanup := testhelper.SetupTestEnvironment(t)
 	defer cleanup()
 
+	cache := diskcache.GetGlobalCache()
+	if err := cache.Clear(); err != nil {
+		t.Fatalf("failed to clear disk cache before test: %v", err)
+	}
+
 	// Ensure uploads dir is cleaned up
 	defer func() {
 		_ = os.RemoveAll("uploads")
 	}()
+	defer func() {
+		if err := cache.Clear(); err != nil {
+			t.Errorf("failed to clear disk cache after test: %v", err)
+		}
+	}()
 
 	// Create test user
 	user := model.User{
@@ -282,25 +292,31 @@ func TestImageCompression(t *testing.T) {
 			t.Errorf("expected Content-Type image/webp, got %s", w.Header().Get("Content-Type"))
 		}
 
-		// Check if local cache file was created
-		cachePath := filepath.Join("uploads", "cache", "compressed_3001_medium.webp")
-		if _, err := os.Stat(cachePath); os.IsNotExist(err) {
-			t.Errorf("expected cached webp file to be created at %s, but it doesn't exist", cachePath)
+		cacheKey := imageCompressionCacheKey(&uploadRecord, "medium")
+		cachedBytes, err := cache.Get(cacheKey)
+		if err != nil {
+			t.Fatalf("disk cache Get(%q) returned error: %v", cacheKey, err)
+		}
+		if !bytes.Equal(cachedBytes, w.Body.Bytes()) {
+			t.Errorf("cached compressed image differs from response")
 		}
 
-		// Subsequent request should hit the cache (modify the cached file to verify)
-		testBytes := []byte("cached webp content")
-		if err := os.WriteFile(cachePath, testBytes, 0644); err != nil {
-			t.Fatalf("failed to write test bytes to cache: %v", err)
+		if err := os.Remove(filePath); err != nil {
+			t.Fatalf("failed to remove source image before cache-hit request: %v", err)
 		}
+		t.Cleanup(func() {
+			if err := os.WriteFile(filePath, pngBuf.Bytes(), 0644); err != nil {
+				t.Errorf("failed to restore source image: %v", err)
+			}
+		})
 
 		w2 := httptest.NewRecorder()
 		r.ServeHTTP(w2, req)
 		if w2.Code != http.StatusOK {
 			t.Fatalf("expected status 200, got %d", w2.Code)
 		}
-		if string(w2.Body.Bytes()) != "cached webp content" {
-			t.Errorf("expected cached content, got %s", string(w2.Body.Bytes()))
+		if !bytes.Equal(w2.Body.Bytes(), cachedBytes) {
+			t.Errorf("cache-hit response differs from cached compressed image")
 		}
 	})
 
@@ -312,10 +328,9 @@ func TestImageCompression(t *testing.T) {
 		if w.Code != http.StatusOK {
 			t.Fatalf("expected status 200, got %d", w.Code)
 		}
-		// Check if local cache file with "high" was created
-		cachePath := filepath.Join("uploads", "cache", "compressed_3001_high.webp")
-		if _, err := os.Stat(cachePath); os.IsNotExist(err) {
-			t.Errorf("expected cached webp file to be created at %s for default level", cachePath)
+		cacheKey := imageCompressionCacheKey(&uploadRecord, "high")
+		if _, err := cache.Get(cacheKey); err != nil {
+			t.Errorf("disk cache Get(%q) returned error: %v", cacheKey, err)
 		}
 	})
 }