| // Copyright 2017 The etcd Authors |
| // |
| // 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 namespace |
| |
| import ( |
| "bytes" |
| "context" |
| |
| "github.com/coreos/etcd/clientv3" |
| ) |
| |
| type leasePrefix struct { |
| clientv3.Lease |
| pfx []byte |
| } |
| |
| // NewLease wraps a Lease interface to filter for only keys with a prefix |
| // and remove that prefix when fetching attached keys through TimeToLive. |
| func NewLease(l clientv3.Lease, prefix string) clientv3.Lease { |
| return &leasePrefix{l, []byte(prefix)} |
| } |
| |
| func (l *leasePrefix) TimeToLive(ctx context.Context, id clientv3.LeaseID, opts ...clientv3.LeaseOption) (*clientv3.LeaseTimeToLiveResponse, error) { |
| resp, err := l.Lease.TimeToLive(ctx, id, opts...) |
| if err != nil { |
| return nil, err |
| } |
| if len(resp.Keys) > 0 { |
| var outKeys [][]byte |
| for i := range resp.Keys { |
| if len(resp.Keys[i]) < len(l.pfx) { |
| // too short |
| continue |
| } |
| if !bytes.Equal(resp.Keys[i][:len(l.pfx)], l.pfx) { |
| // doesn't match prefix |
| continue |
| } |
| // strip prefix |
| outKeys = append(outKeys, resp.Keys[i][len(l.pfx):]) |
| } |
| resp.Keys = outKeys |
| } |
| return resp, nil |
| } |