/
etcd.go
59 lines (49 loc) · 1.25 KB
/
etcd.go
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package etcd
import (
"context"
clientv3 "go.etcd.io/etcd/client/v3"
"go.etcd.io/etcd/client/v3/concurrency"
)
func New(addrs []string, opts ...Option) (*clientv3.Client, error) {
defaultOpts := defaultOptions
for _, o := range opts {
o.apply(&defaultOpts)
}
return clientv3.New(clientv3.Config{
Endpoints: addrs,
DialTimeout: defaultOpts.dialTimeout,
Username: defaultOpts.username,
Password: defaultOpts.password,
TLS: defaultOpts.tls,
})
}
func Elect(ctx context.Context, client *clientv3.Client, pfx, val string, processor func(context.Context)) error {
ctx, cancel := context.WithCancel(ctx)
defer cancel()
session, err := concurrency.NewSession(client, concurrency.WithTTL(10))
if err != nil {
return err
}
defer session.Close()
election := concurrency.NewElection(session, pfx)
if err := election.Campaign(ctx, val); err != nil {
return err
}
// 这里 ctx 不能使用外部传入的,避免不能 resign
defer election.Resign(context.TODO())
go func() {
select {
case <-session.Done():
cancel() // session 过期,取消 ctx
}
}()
// 需要在 processor 中处理 ctx
// select {
// case <-ctx.Done():
// return
// default:
// // do something
// }
processor(ctx)
return nil
}