packer-cn/builder/amazon/chroot/step_attach_volume.go

144 lines
3.8 KiB
Go

package chroot
import (
"errors"
"fmt"
"strings"
"time"
"github.com/aws/aws-sdk-go/service/ec2"
"github.com/mitchellh/multistep"
awscommon "github.com/mitchellh/packer/builder/amazon/common"
"github.com/mitchellh/packer/packer"
)
// StepAttachVolume attaches the previously created volume to an
// available device location.
//
// Produces:
// device string - The location where the volume was attached.
// attach_cleanup CleanupFunc
type StepAttachVolume struct {
attached bool
volumeId string
}
func (s *StepAttachVolume) Run(state multistep.StateBag) multistep.StepAction {
ec2conn := state.Get("ec2").(*ec2.EC2)
device := state.Get("device").(string)
instance := state.Get("instance").(*ec2.Instance)
ui := state.Get("ui").(packer.Ui)
volumeId := state.Get("volume_id").(string)
// For the API call, it expects "sd" prefixed devices.
attachVolume := strings.Replace(device, "/xvd", "/sd", 1)
ui.Say(fmt.Sprintf("Attaching the root volume to %s", attachVolume))
_, err := ec2conn.AttachVolume(&ec2.AttachVolumeInput{
InstanceID: instance.InstanceID,
VolumeID: &volumeId,
Device: &attachVolume,
})
if err != nil {
err := fmt.Errorf("Error attaching volume: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
// Mark that we attached it so we can detach it later
s.attached = true
s.volumeId = volumeId
// Wait for the volume to become attached
stateChange := awscommon.StateChangeConf{
Pending: []string{"attaching"},
StepState: state,
Target: "attached",
Refresh: func() (interface{}, string, error) {
attempts := 0
for attempts < 30 {
resp, err := ec2conn.DescribeVolumes(&ec2.DescribeVolumesInput{VolumeIDs: []*string{&volumeId}})
if err != nil {
return nil, "", err
}
if len(resp.Volumes[0].Attachments) > 0 {
a := resp.Volumes[0].Attachments[0]
return a, *a.State, nil
}
// When Attachment on volume is not present sleep for 2s and retry
attempts += 1
ui.Say(fmt.Sprintf(
"Volume %s show no attachments. Attempt %d/30. Sleeping for 2s and will retry.",
volumeId, attempts))
time.Sleep(2 * time.Second)
}
// Attachment on volume is not present after all attempts
return nil, "", errors.New("No attachments on volume.")
},
}
_, err = awscommon.WaitForState(&stateChange)
if err != nil {
err := fmt.Errorf("Error waiting for volume: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
state.Put("attach_cleanup", s)
return multistep.ActionContinue
}
func (s *StepAttachVolume) Cleanup(state multistep.StateBag) {
ui := state.Get("ui").(packer.Ui)
if err := s.CleanupFunc(state); err != nil {
ui.Error(err.Error())
}
}
func (s *StepAttachVolume) CleanupFunc(state multistep.StateBag) error {
if !s.attached {
return nil
}
ec2conn := state.Get("ec2").(*ec2.EC2)
ui := state.Get("ui").(packer.Ui)
ui.Say("Detaching EBS volume...")
_, err := ec2conn.DetachVolume(&ec2.DetachVolumeInput{VolumeID: &s.volumeId})
if err != nil {
return fmt.Errorf("Error detaching EBS volume: %s", err)
}
s.attached = false
// Wait for the volume to detach
stateChange := awscommon.StateChangeConf{
Pending: []string{"attaching", "attached", "detaching"},
StepState: state,
Target: "detached",
Refresh: func() (interface{}, string, error) {
resp, err := ec2conn.DescribeVolumes(&ec2.DescribeVolumesInput{VolumeIDs: []*string{&s.volumeId}})
if err != nil {
return nil, "", err
}
v := resp.Volumes[0]
if len(v.Attachments) > 0 {
return v, *v.Attachments[0].State, nil
} else {
return v, "detached", nil
}
},
}
_, err = awscommon.WaitForState(&stateChange)
if err != nil {
return fmt.Errorf("Error waiting for volume: %s", err)
}
return nil
}