mirror of
https://gitee.com/rainbond/Rainbond.git
synced 2024-12-02 19:57:42 +08:00
62 lines
1.9 KiB
Go
62 lines
1.9 KiB
Go
|
|
// RAINBOND, Application Management Platform
|
|
// Copyright (C) 2014-2017 Goodrain Co., Ltd.
|
|
|
|
// This program is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version. For any non-GPL usage of Rainbond,
|
|
// one or multiple Commercial Licenses authorized by Goodrain Co., Ltd.
|
|
// must be obtained first.
|
|
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package etcd
|
|
|
|
import (
|
|
"errors"
|
|
|
|
v3 "github.com/coreos/etcd/clientv3"
|
|
spb "github.com/coreos/etcd/mvcc/mvccpb"
|
|
"golang.org/x/net/context"
|
|
)
|
|
|
|
var (
|
|
ErrKeyExists = errors.New("key already exists")
|
|
ErrWaitMismatch = errors.New("unexpected wait result")
|
|
ErrTooManyClients = errors.New("too many clients")
|
|
ErrNoWatcher = errors.New("no watcher channel")
|
|
)
|
|
|
|
// deleteRevKey deletes a key by revision, returning false if key is missing
|
|
func deleteRevKey(ctx context.Context, kv v3.KV, key string, rev int64) (bool, error) {
|
|
cmp := v3.Compare(v3.ModRevision(key), "=", rev)
|
|
req := v3.OpDelete(key)
|
|
txnresp, err := kv.Txn(ctx).If(cmp).Then(req).Commit()
|
|
if err != nil {
|
|
return false, err
|
|
} else if !txnresp.Succeeded {
|
|
return false, nil
|
|
}
|
|
return true, nil
|
|
}
|
|
|
|
//claimFirstKey 获取队列第一个key,并从队列删除
|
|
func claimFirstKey(ctx context.Context, kv v3.KV, kvs []*spb.KeyValue) (*spb.KeyValue, error) {
|
|
for _, k := range kvs {
|
|
ok, err := deleteRevKey(ctx, kv, string(k.Key), k.ModRevision)
|
|
if err != nil {
|
|
return nil, err
|
|
} else if ok {
|
|
return k, nil
|
|
}
|
|
}
|
|
return nil, nil
|
|
}
|