blob: 0464fe7e68152518c3d83c89a01061d0e3fd55c1 [file] [log] [blame]
// Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package datastore
import (
"encoding/base64"
"strings"
"cloud.google.com/go/datastore/internal/gaepb"
"github.com/golang/protobuf/proto"
)
// decodeGAEKey attempts to decode the given encoded key generated by the
// GAE Datastore package (google.golang.org/appengine/datastore), returning nil
// if the key couldn't be decoded.
func decodeGAEKey(encoded string) *Key {
// Re-add padding.
if m := len(encoded) % 4; m != 0 {
encoded += strings.Repeat("=", 4-m)
}
b, err := base64.URLEncoding.DecodeString(encoded)
if err != nil {
return nil
}
ref := new(gaepb.Reference)
if err := proto.Unmarshal(b, ref); err != nil {
return nil
}
return gaeProtoToKey(ref)
}
// gaeProtoToKey accepts a GAE Datastore key and converts it to a Cloud Datastore key.
// This is adapted from the "protoToKey" function in the appengine/datastore package.
//
// NOTE(cbro): this is a lossy operation, as GAE Datastore keys include the project/app ID,
// but Cloud Datastore keys do not.
func gaeProtoToKey(r *gaepb.Reference) *Key {
namespace := r.GetNameSpace()
var k *Key
for _, e := range r.Path.Element {
k = &Key{
Kind: e.GetType(),
Name: e.GetName(),
ID: e.GetId(),
Parent: k,
Namespace: namespace,
}
}
if !k.valid() {
return nil
}
return k
}