added google drive

pkg/utils/path.go

@@ -0,0 +1,81 @@
+package utils
+
+import (
+	"errors"
+	"net/url"
+	stdpath "path"
+	"strings"
+)
+
+// FixAndCleanPath
+// The upper layer of the root directory is still the root directory.
+// So ".." And "." will be cleared
+// for example
+// 1. ".." or "." => "/"
+// 2. "../..." or "./..." => "/..."
+// 3. "../.x." or "./.x." => "/.x."
+// 4. "x//\\y" = > "/z/x"
+func FixAndCleanPath(path string) string {
+	path = strings.ReplaceAll(path, "\\", "/")
+	if !strings.HasPrefix(path, "/") {
+		path = "/" + path
+	}
+	return stdpath.Clean(path)
+}
+
+// PathAddSeparatorSuffix Add path '/' suffix
+// for example /root => /root/
+func PathAddSeparatorSuffix(path string) string {
+	if !strings.HasSuffix(path, "/") {
+		path = path + "/"
+	}
+	return path
+}
+
+// PathEqual judge path is equal
+func PathEqual(path1, path2 string) bool {
+	return FixAndCleanPath(path1) == FixAndCleanPath(path2)
+}
+
+func IsSubPath(path string, subPath string) bool {
+	path, subPath = FixAndCleanPath(path), FixAndCleanPath(subPath)
+	return path == subPath || strings.HasPrefix(subPath, PathAddSeparatorSuffix(path))
+}
+
+func Ext(path string) string {
+	ext := stdpath.Ext(path)
+	if strings.HasPrefix(ext, ".") {
+		return ext[1:]
+	}
+	return ext
+}
+
+func EncodePath(path string, all ...bool) string {
+	seg := strings.Split(path, "/")
+	toReplace := []struct {
+		Src string
+		Dst string
+	}{
+		{Src: "%", Dst: "%25"},
+		{"%", "%25"},
+		{"?", "%3F"},
+		{"#", "%23"},
+	}
+	for i := range seg {
+		if len(all) > 0 && all[0] {
+			seg[i] = url.PathEscape(seg[i])
+		} else {
+			for j := range toReplace {
+				seg[i] = strings.ReplaceAll(seg[i], toReplace[j].Src, toReplace[j].Dst)
+			}
+		}
+	}
+	return strings.Join(seg, "/")
+}
+
+func JoinBasePath(basePath, reqPath string) (string, error) {
+	if strings.HasSuffix(reqPath, "..") || strings.Contains(reqPath, "../") {
+		return "", errors.New("access using relative path is not allowed")
+	}
+	return stdpath.Join(FixAndCleanPath(basePath), FixAndCleanPath(reqPath)), nil
+}