packer-cn/builder/amazon/common/access_config.go

121 lines
3.1 KiB
Go

package common
import (
"fmt"
"log"
"os"
"time"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/credentials"
"github.com/aws/aws-sdk-go/aws/ec2metadata"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/hashicorp/go-cleanhttp"
"github.com/hashicorp/packer/template/interpolate"
)
// AccessConfig is for common configuration related to AWS access
type AccessConfig struct {
AccessKey string `mapstructure:"access_key"`
CustomEndpointEc2 string `mapstructure:"custom_endpoint_ec2"`
MFACode string `mapstructure:"mfa_code"`
ProfileName string `mapstructure:"profile"`
RawRegion string `mapstructure:"region"`
SecretKey string `mapstructure:"secret_key"`
SkipValidation bool `mapstructure:"skip_region_validation"`
Token string `mapstructure:"token"`
session *session.Session
}
// 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) Session() (*session.Session, error) {
if c.session != nil {
return c.session, nil
}
if c.ProfileName != "" {
if err := os.Setenv("AWS_PROFILE", c.ProfileName); err != nil {
return nil, fmt.Errorf("Set env error: %s", err)
}
}
config := aws.NewConfig().WithMaxRetries(11).WithCredentialsChainVerboseErrors(true)
if region := c.region(); region != "" {
config = config.WithRegion(region)
}
if c.CustomEndpointEc2 != "" {
config = config.WithEndpoint(c.CustomEndpointEc2)
}
if c.AccessKey != "" {
creds := credentials.NewChainCredentials(
[]credentials.Provider{
&credentials.StaticProvider{
Value: credentials.Value{
AccessKeyID: c.AccessKey,
SecretAccessKey: c.SecretKey,
SessionToken: c.Token,
},
},
})
config = config.WithCredentials(creds)
}
opts := session.Options{
SharedConfigState: session.SharedConfigEnable,
Config: *config,
}
if c.MFACode != "" {
opts.AssumeRoleTokenProvider = func() (string, error) {
return c.MFACode, nil
}
}
var err error
c.session, err = session.NewSessionWithOptions(opts)
if err != nil {
return nil, err
}
return c.session, nil
}
// region returns either the region from config or region from metadata service
func (c *AccessConfig) region() string {
if c.RawRegion != "" {
return c.RawRegion
}
client := cleanhttp.DefaultClient()
// Keep the default timeout (100ms) low as we don't want to wait in non-EC2 environments
client.Timeout = 100 * time.Millisecond
ec2meta := ec2metadata.New(session.New(), &aws.Config{
HTTPClient: client,
})
region, err := ec2meta.Region()
if err != nil {
log.Println("Error getting region from metadata service, "+
"probably because we're not running on AWS.", err)
return ""
}
return region
}
func (c *AccessConfig) Prepare(ctx *interpolate.Context) []error {
var errs []error
if c.RawRegion != "" && !c.SkipValidation {
if valid := ValidateRegion(c.RawRegion); !valid {
errs = append(errs, fmt.Errorf("Unknown region: %s", c.RawRegion))
}
}
if len(errs) > 0 {
return errs
}
return nil
}