71 lines
1.8 KiB
Go
71 lines
1.8 KiB
Go
/*
|
|
Copyright 2017 The Kubernetes 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 preflight
|
|
|
|
import (
|
|
"fmt"
|
|
"math/rand"
|
|
"net"
|
|
"net/url"
|
|
"time"
|
|
)
|
|
|
|
const connectionTimeout = 1 * time.Second
|
|
|
|
// EtcdConnection holds the Etcd server list
|
|
type EtcdConnection struct {
|
|
ServerList []string
|
|
}
|
|
|
|
func (EtcdConnection) serverReachable(connURL *url.URL) bool {
|
|
scheme := connURL.Scheme
|
|
if scheme == "http" || scheme == "https" || scheme == "tcp" {
|
|
scheme = "tcp"
|
|
}
|
|
if conn, err := net.DialTimeout(scheme, connURL.Host, connectionTimeout); err == nil {
|
|
defer conn.Close()
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
func parseServerURI(serverURI string) (*url.URL, error) {
|
|
connURL, err := url.Parse(serverURI)
|
|
if err != nil {
|
|
return &url.URL{}, fmt.Errorf("unable to parse etcd url: %v", err)
|
|
}
|
|
return connURL, nil
|
|
}
|
|
|
|
// CheckEtcdServers will attempt to reach all etcd servers once. If any
|
|
// can be reached, return true.
|
|
func (con EtcdConnection) CheckEtcdServers() (done bool, err error) {
|
|
// Attempt to reach every Etcd server randomly.
|
|
serverNumber := len(con.ServerList)
|
|
serverPerms := rand.Perm(serverNumber)
|
|
for _, index := range serverPerms {
|
|
host, err := parseServerURI(con.ServerList[index])
|
|
if err != nil {
|
|
return false, err
|
|
}
|
|
if con.serverReachable(host) {
|
|
return true, nil
|
|
}
|
|
}
|
|
return false, nil
|
|
}
|