packer-cn/builder/amazon/common/access_config.go
Matthew Hooker 9a91ae4e8f
fix new session error when creating cred chain.
the old and deprecated method won't error and so is safe to use
even if we're not in amazon.
2016-11-14 11:39:22 -08:00

120 lines
3.1 KiB
Go

package common
import (
"fmt"
"io/ioutil"
"net/http"
"strings"
"unicode"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/credentials/ec2rolecreds"
"github.com/aws/aws-sdk-go/aws/ec2metadata"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/mitchellh/packer/template/interpolate"
)
// AccessConfig is for common configuration related to AWS access
type AccessConfig struct {
AccessKey string `mapstructure:"access_key"`
SecretKey string `mapstructure:"secret_key"`
RawRegion string `mapstructure:"region"`
SkipValidation bool `mapstructure:"skip_region_validation"`
Token string `mapstructure:"token"`
ProfileName string `mapstructure:"profile"`
}
// Config returns a valid aws.Config object for access to AWS services, or
// an error if the authentication and region couldn't be resolved
func (c *AccessConfig) Config() (*aws.Config, error) {
var creds *credentials.Credentials
region, err := c.Region()
if err != nil {
return nil, err
}
config := aws.NewConfig().WithRegion(region).WithMaxRetries(11)
if c.ProfileName != "" {
profile, err := NewFromProfile(c.ProfileName)
if err != nil {
return nil, err
}
creds, err = profile.CredentialsFromProfile(config)
if err != nil {
return nil, err
}
} else {
creds = credentials.NewChainCredentials([]credentials.Provider{
&credentials.StaticProvider{Value: credentials.Value{
AccessKeyID: c.AccessKey,
SecretAccessKey: c.SecretKey,
SessionToken: c.Token,
}},
&credentials.EnvProvider{},
&credentials.SharedCredentialsProvider{Filename: "", Profile: ""},
&ec2rolecreds.EC2RoleProvider{
Client: ec2metadata.New(session.New(config)),
},
})
}
return config.WithCredentials(creds), nil
}
// Region returns the aws.Region object for access to AWS services, requesting
// the region from the instance metadata if possible.
func (c *AccessConfig) Region() (string, error) {
if c.RawRegion != "" {
if !c.SkipValidation {
if valid := ValidateRegion(c.RawRegion); valid == false {
return "", fmt.Errorf("Not a valid region: %s", c.RawRegion)
}
}
return c.RawRegion, nil
}
md, err := GetInstanceMetaData("placement/availability-zone")
if err != nil {
return "", err
}
region := strings.TrimRightFunc(string(md), unicode.IsLetter)
return region, nil
}
func (c *AccessConfig) Prepare(ctx *interpolate.Context) []error {
var errs []error
if c.RawRegion != "" && !c.SkipValidation {
if valid := ValidateRegion(c.RawRegion); valid == false {
errs = append(errs, fmt.Errorf("Unknown region: %s", c.RawRegion))
}
}
if len(errs) > 0 {
return errs
}
return nil
}
func GetInstanceMetaData(path string) (contents []byte, err error) {
url := "http://169.254.169.254/latest/meta-data/" + path
resp, err := http.Get(url)
if err != nil {
return
}
defer resp.Body.Close()
if resp.StatusCode != 200 {
err = fmt.Errorf("Code %d returned for url %s", resp.StatusCode, url)
return
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return
}
return []byte(body), err
}