cloudinit/datasource/metadata/ec2/metadata.go
2015-08-23 19:30:03 -07:00

116 lines
3.3 KiB
Go

// Copyright 2015 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 ec2
import (
"bufio"
"bytes"
"fmt"
"log"
"net"
"strings"
"github.com/coreos/coreos-cloudinit/datasource"
"github.com/coreos/coreos-cloudinit/datasource/metadata"
"github.com/coreos/coreos-cloudinit/pkg"
)
const (
DefaultAddress = "http://169.254.169.254/"
apiVersion = "2009-04-04/"
userdataPath = apiVersion + "user-data"
metadataPath = apiVersion + "meta-data"
)
type metadataService struct {
metadata.MetadataService
}
func NewDatasource(root string) *metadataService {
return &metadataService{metadata.NewDatasource(root, apiVersion, userdataPath, metadataPath)}
}
func (ms metadataService) FetchMetadata() (datasource.Metadata, error) {
metadata := datasource.Metadata{}
if keynames, err := ms.fetchAttributes(fmt.Sprintf("%s/public-keys", ms.MetadataUrl())); err == nil {
keyIDs := make(map[string]string)
for _, keyname := range keynames {
tokens := strings.SplitN(keyname, "=", 2)
if len(tokens) != 2 {
return metadata, fmt.Errorf("malformed public key: %q", keyname)
}
keyIDs[tokens[1]] = tokens[0]
}
metadata.SSHPublicKeys = map[string]string{}
for name, id := range keyIDs {
sshkey, err := ms.fetchAttribute(fmt.Sprintf("%s/public-keys/%s/openssh-key", ms.MetadataUrl(), id))
if err != nil {
return metadata, err
}
metadata.SSHPublicKeys[name] = sshkey
log.Printf("Found SSH key for %q\n", name)
}
} else if _, ok := err.(pkg.ErrNotFound); !ok {
return metadata, err
}
if hostname, err := ms.fetchAttribute(fmt.Sprintf("%s/hostname", ms.MetadataUrl())); err == nil {
metadata.Hostname = strings.Split(hostname, " ")[0]
} else if _, ok := err.(pkg.ErrNotFound); !ok {
return metadata, err
}
if localAddr, err := ms.fetchAttribute(fmt.Sprintf("%s/local-ipv4", ms.MetadataUrl())); err == nil {
metadata.PrivateIPv4 = net.ParseIP(localAddr)
} else if _, ok := err.(pkg.ErrNotFound); !ok {
return metadata, err
}
if publicAddr, err := ms.fetchAttribute(fmt.Sprintf("%s/public-ipv4", ms.MetadataUrl())); err == nil {
metadata.PublicIPv4 = net.ParseIP(publicAddr)
} else if _, ok := err.(pkg.ErrNotFound); !ok {
return metadata, err
}
return metadata, nil
}
func (ms metadataService) Type() string {
return "ec2-metadata-service"
}
func (ms metadataService) fetchAttributes(url string) ([]string, error) {
resp, err := ms.FetchData(url)
if err != nil {
return nil, err
}
scanner := bufio.NewScanner(bytes.NewBuffer(resp))
data := make([]string, 0)
for scanner.Scan() {
data = append(data, scanner.Text())
}
return data, scanner.Err()
}
func (ms metadataService) fetchAttribute(url string) (string, error) {
if attrs, err := ms.fetchAttributes(url); err == nil && len(attrs) > 0 {
return attrs[0], nil
} else {
return "", err
}
}