traefik/vendor/github.com/mesos/mesos-go/detector/zoo/client2.go
2017-03-09 13:13:02 +01:00

88 lines
1.6 KiB
Go

package zoo
import (
"sync"
"time"
"github.com/samuel/go-zookeeper/zk"
)
const (
defaultSessionTimeout = 60 * time.Second
currentPath = "."
)
var zkSessionTimeout = defaultSessionTimeout
type client2 struct {
*zk.Conn
path string
done chan struct{} // signal chan, closes when the underlying connection terminates
stopOnce sync.Once
}
func connect2(hosts []string, path string) (*client2, error) {
c, ev, err := zk.Connect(hosts, zkSessionTimeout)
if err != nil {
return nil, err
}
done := make(chan struct{})
go func() {
// close the 'done' chan when the zk event chan closes (signals termination of zk connection)
defer close(done)
for {
if _, ok := <-ev; !ok {
return
}
}
}()
return &client2{
Conn: c,
path: path,
done: done,
}, nil
}
func (c *client2) stopped() <-chan struct{} {
return c.done
}
func (c *client2) stop() {
c.stopOnce.Do(c.Close)
}
func (c *client2) data(path string) (data []byte, err error) {
data, _, err = c.Get(path)
return
}
func (c *client2) watchChildren(path string) (string, <-chan []string, <-chan error) {
errCh := make(chan error, 1)
snap := make(chan []string)
watchPath := c.path
if path != "" && path != currentPath {
watchPath = watchPath + path
}
go func() {
defer close(errCh)
for {
children, _, ev, err := c.ChildrenW(watchPath)
if err != nil {
errCh <- err
return
}
select {
case snap <- children:
case <-c.done:
return
}
e := <-ev // wait for the next watch-related event
if e.Err != nil {
errCh <- e.Err
return
}
}
}()
return watchPath, snap, errCh
}