blob: e4cf7751740114b33e178fccb4c0168afee9bdb6 [file] [log] [blame]
Holger Hildebrandtfa074992020-03-27 15:42:06 +00001// Copyright 2016 The etcd Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package concurrency
16
17import (
18 "context"
19 "fmt"
20
21 v3 "go.etcd.io/etcd/clientv3"
22 pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
23 "go.etcd.io/etcd/mvcc/mvccpb"
24)
25
26func waitDelete(ctx context.Context, client *v3.Client, key string, rev int64) error {
27 cctx, cancel := context.WithCancel(ctx)
28 defer cancel()
29
30 var wr v3.WatchResponse
31 wch := client.Watch(cctx, key, v3.WithRev(rev))
32 for wr = range wch {
33 for _, ev := range wr.Events {
34 if ev.Type == mvccpb.DELETE {
35 return nil
36 }
37 }
38 }
39 if err := wr.Err(); err != nil {
40 return err
41 }
42 if err := ctx.Err(); err != nil {
43 return err
44 }
45 return fmt.Errorf("lost watcher waiting for delete")
46}
47
48// waitDeletes efficiently waits until all keys matching the prefix and no greater
49// than the create revision.
50func waitDeletes(ctx context.Context, client *v3.Client, pfx string, maxCreateRev int64) (*pb.ResponseHeader, error) {
51 getOpts := append(v3.WithLastCreate(), v3.WithMaxCreateRev(maxCreateRev))
52 for {
53 resp, err := client.Get(ctx, pfx, getOpts...)
54 if err != nil {
55 return nil, err
56 }
57 if len(resp.Kvs) == 0 {
58 return resp.Header, nil
59 }
60 lastKey := string(resp.Kvs[0].Key)
61 if err = waitDelete(ctx, client, lastKey, resp.Header.Revision); err != nil {
62 return nil, err
63 }
64 }
65}