// monitor checks for changes in a path-based connection
func (zconn *zconn) monitor(path string) {
var (
connC chan<- client.Connection
conn client.Connection
err error
)
defer func() {
if conn != nil {
conn.Close()
}
}()
for {
// wait for someone to request a connection, or shutdown
select {
case connC = <-zconn.connC:
case <-zconn.shutdownC:
return
}
retry:
// create a connection if it doesn't exist or ping the existing connection
if conn == nil {
conn, err = zconn.client.GetCustomConnection(path)
if err != nil {
glog.Warningf("Could not obtain a connection to %s: %s", path, err)
}
} else if _, err := conn.Children("/"); err == client.ErrConnectionClosed {
glog.Warningf("Could not ping connection to %s: %s", path, err)
conn = nil
}
// send the connection back
if conn != nil {
connC <- conn
continue
}
// if conn is nil, try to create a new connection
select {
case <-time.After(time.Second):
glog.Infof("Refreshing connection to zookeeper")
goto retry
case <-zconn.shutdownC:
return
}
}
}