Feat: hash id decode and verification

pkg/hashid/hash.go

@@ -1,6 +1,9 @@
 package hashid
 
-import "github.com/HFO4/cloudreve/pkg/conf"
+import (
+	"errors"
+	"github.com/HFO4/cloudreve/pkg/conf"
+)
 import "github.com/speps/go-hashids"
 
 // ID类型
@@ -9,6 +12,10 @@ const (
 	UserID         // 用户
 )
 
+var (
+	ErrTypeNotMatch = errors.New("ID类型不匹配")
+)
+
 // HashEncode 对给定数据计算HashID
 func HashEncode(v []int) (string, error) {
 	hd := hashids.NewData()
@@ -26,8 +33,32 @@ func HashEncode(v []int) (string, error) {
 	return id, nil
 }
 
+// HashDecode 对给定数据计算原始数据
+func HashDecode(raw string) ([]int, error) {
+	hd := hashids.NewData()
+	hd.Salt = conf.SystemConfig.HashIDSalt
+
+	h, err := hashids.NewWithData(hd)
+	if err != nil {
+		return []int{}, err
+	}
+
+	return h.DecodeWithError(raw)
+
+}
+
 // HashID 计算数据库内主键对应的HashID
 func HashID(id uint, t int) string {
 	v, _ := HashEncode([]int{int(id), t})
 	return v
 }
+
+// DecodeHashID 计算HashID对应的数据库ID
+// TODO 测试
+func DecodeHashID(id string, t int) (uint, error) {
+	v, _ := HashDecode(id)
+	if len(v) != 2 || v[1] != t {
+		return 0, ErrTypeNotMatch
+	}
+	return uint(v[0]), nil
+}