2016-05-13 06:51:48 +03:00
|
|
|
// Copyright 2015 The etcd Authors
|
2015-04-17 17:57:01 +03:00
|
|
|
//
|
|
|
|
// 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 client
|
|
|
|
|
|
|
|
import (
|
|
|
|
"fmt"
|
|
|
|
"net"
|
|
|
|
"net/url"
|
|
|
|
)
|
|
|
|
|
|
|
|
var (
|
|
|
|
// indirection for testing
|
|
|
|
lookupSRV = net.LookupSRV
|
|
|
|
)
|
|
|
|
|
|
|
|
type srvDiscover struct{}
|
|
|
|
|
2016-02-01 08:42:39 +03:00
|
|
|
// NewSRVDiscover constructs a new Discoverer that uses the stdlib to lookup SRV records.
|
2015-04-17 17:57:01 +03:00
|
|
|
func NewSRVDiscover() Discoverer {
|
|
|
|
return &srvDiscover{}
|
|
|
|
}
|
|
|
|
|
|
|
|
// Discover looks up the etcd servers for the domain.
|
|
|
|
func (d *srvDiscover) Discover(domain string) ([]string, error) {
|
|
|
|
var urls []*url.URL
|
|
|
|
|
|
|
|
updateURLs := func(service, scheme string) error {
|
|
|
|
_, addrs, err := lookupSRV(service, "tcp", domain)
|
|
|
|
if err != nil {
|
|
|
|
return err
|
|
|
|
}
|
|
|
|
for _, srv := range addrs {
|
|
|
|
urls = append(urls, &url.URL{
|
|
|
|
Scheme: scheme,
|
|
|
|
Host: net.JoinHostPort(srv.Target, fmt.Sprintf("%d", srv.Port)),
|
|
|
|
})
|
|
|
|
}
|
|
|
|
return nil
|
|
|
|
}
|
|
|
|
|
2016-01-12 07:22:53 +03:00
|
|
|
errHTTPS := updateURLs("etcd-client-ssl", "https")
|
|
|
|
errHTTP := updateURLs("etcd-client", "http")
|
2015-04-17 17:57:01 +03:00
|
|
|
|
|
|
|
if errHTTPS != nil && errHTTP != nil {
|
|
|
|
return nil, fmt.Errorf("dns lookup errors: %s and %s", errHTTPS, errHTTP)
|
|
|
|
}
|
|
|
|
|
|
|
|
endpoints := make([]string, len(urls))
|
|
|
|
for i := range urls {
|
|
|
|
endpoints[i] = urls[i].String()
|
|
|
|
}
|
|
|
|
return endpoints, nil
|
|
|
|
}
|