feat: s3 server support (#6088 close #5186)

Currently tested: List, Get, Remove

server/s3/list.go

@@ -0,0 +1,53 @@
+// Credits: https://pkg.go.dev/github.com/rclone/rclone@v1.65.2/cmd/serve/s3
+// Package s3 implements a fake s3 server for alist
+package s3
+
+import (
+	"path"
+	"strings"
+
+	"github.com/Mikubill/gofakes3"
+)
+
+func (b *s3Backend) entryListR(bucket, fdPath, name string, addPrefix bool, response *gofakes3.ObjectList) error {
+	fp := path.Join(bucket, fdPath)
+
+	dirEntries, err := getDirEntries(fp)
+	if err != nil {
+		return err
+	}
+
+	for _, entry := range dirEntries {
+		object := entry.GetName()
+
+		// workround for control-chars detect
+		objectPath := path.Join(fdPath, object)
+
+		if !strings.HasPrefix(object, name) {
+			continue
+		}
+
+		if entry.IsDir() {
+			if addPrefix {
+				// response.AddPrefix(gofakes3.URLEncode(objectPath))
+				response.AddPrefix(objectPath)
+				continue
+			}
+			err := b.entryListR(bucket, path.Join(fdPath, object), "", false, response)
+			if err != nil {
+				return err
+			}
+		} else {
+			item := &gofakes3.Content{
+				// Key:          gofakes3.URLEncode(objectPath),
+				Key:          objectPath,
+				LastModified: gofakes3.NewContentTime(entry.ModTime()),
+				ETag:         getFileHash(entry),
+				Size:         entry.GetSize(),
+				StorageClass: gofakes3.StorageStandard,
+			}
+			response.Add(item)
+		}
+	}
+	return nil
+}