2014-10-17 15:36:22 -07:00

125 lines
2.7 KiB
Go

/*
Copyright 2014 CoreOS, Inc.
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 waagent
import (
"encoding/json"
"encoding/xml"
"fmt"
"io/ioutil"
"net"
"os"
"path"
)
type waagent struct {
root string
readFile func(filename string) ([]byte, error)
}
func NewDatasource(root string) *waagent {
return &waagent{root, ioutil.ReadFile}
}
func (a *waagent) IsAvailable() bool {
_, err := os.Stat(path.Join(a.root, "provisioned"))
return !os.IsNotExist(err)
}
func (a *waagent) AvailabilityChanges() bool {
return true
}
func (a *waagent) ConfigRoot() string {
return a.root
}
func (a *waagent) FetchMetadata() ([]byte, error) {
metadataBytes, err := a.tryReadFile(path.Join(a.root, "SharedConfig.xml"))
if err != nil {
return nil, err
}
if len(metadataBytes) == 0 {
return metadataBytes, nil
}
type Instance struct {
Id string `xml:"id,attr"`
Address string `xml:"address,attr"`
InputEndpoints struct {
Endpoints []struct {
LoadBalancedPublicAddress string `xml:"loadBalancedPublicAddress,attr"`
} `xml:"Endpoint"`
}
}
type SharedConfig struct {
Incarnation struct {
Instance string `xml:"instance,attr"`
}
Instances struct {
Instances []Instance `xml:"Instance"`
}
}
var metadata SharedConfig
if err := xml.Unmarshal(metadataBytes, &metadata); err != nil {
return nil, err
}
var instance Instance
for _, i := range metadata.Instances.Instances {
if i.Id == metadata.Incarnation.Instance {
instance = i
break
}
}
attrs := map[string]string{
"local-ipv4": instance.Address,
}
for _, e := range instance.InputEndpoints.Endpoints {
host, _, err := net.SplitHostPort(e.LoadBalancedPublicAddress)
if err == nil {
attrs["public-ipv4"] = host
break
}
}
return json.Marshal(attrs)
}
func (a *waagent) FetchUserdata() ([]byte, error) {
return a.tryReadFile(path.Join(a.root, "CustomData"))
}
func (a *waagent) FetchNetworkConfig(filename string) ([]byte, error) {
return nil, nil
}
func (a *waagent) Type() string {
return "waagent"
}
func (a *waagent) tryReadFile(filename string) ([]byte, error) {
fmt.Printf("Attempting to read from %q\n", filename)
data, err := a.readFile(filename)
if os.IsNotExist(err) {
err = nil
}
return data, err
}