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

106 lines
2.6 KiB
Go

package chroot
import (
"bytes"
"fmt"
"github.com/mitchellh/multistep"
"github.com/mitchellh/packer/packer"
"log"
"os"
"path/filepath"
)
type mountPathData struct {
Device string
}
// StepMountDevice mounts the attached device.
//
// Produces:
// mount_path string - The location where the volume was mounted.
// mount_device_cleanup CleanupFunc - To perform early cleanup
type StepMountDevice struct {
mountPath string
}
func (s *StepMountDevice) Run(state multistep.StateBag) multistep.StepAction {
config := state.Get("config").(*Config)
ui := state.Get("ui").(packer.Ui)
device := state.Get("device").(string)
mountPath, err := config.tpl.Process(config.MountPath, &mountPathData{
Device: filepath.Base(device),
})
if err != nil {
err := fmt.Errorf("Error preparing mount directory: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
mountPath, err = filepath.Abs(mountPath)
if err != nil {
err := fmt.Errorf("Error preparing mount directory: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
log.Printf("Mount path: %s", mountPath)
if err := os.MkdirAll(mountPath, 0755); err != nil {
err := fmt.Errorf("Error creating mount directory: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
ui.Say("Mounting the root device...")
stderr := new(bytes.Buffer)
mountCommand := fmt.Sprintf("mount %s %s", device, mountPath)
wrappedCommand := state.Get("wrappedCommand").(Command)
cmd := wrappedCommand(mountCommand)
cmd.Stderr = stderr
if err := cmd.Run(); err != nil {
err := fmt.Errorf(
"Error mounting root volume: %s\nStderr: %s", err, stderr.String())
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
// Set the mount path so we remember to unmount it later
s.mountPath = mountPath
state.Put("mount_path", s.mountPath)
state.Put("mount_device_cleanup", s)
return multistep.ActionContinue
}
func (s *StepMountDevice) Cleanup(state multistep.StateBag) {
ui := state.Get("ui").(packer.Ui)
if err := s.CleanupFunc(state); err != nil {
ui.Error(err.Error())
}
}
func (s *StepMountDevice) CleanupFunc(state multistep.StateBag) error {
if s.mountPath == "" {
return nil
}
ui := state.Get("ui").(packer.Ui)
ui.Say("Unmounting the root device...")
unmountCommand := fmt.Sprintf("umount %s", s.mountPath)
wrappedCommand := state.Get("wrappedCommand").(Command)
cmd := wrappedCommand(unmountCommand)
if err := cmd.Run(); err != nil {
return fmt.Errorf("Error unmounting root device: %s", err)
}
s.mountPath = ""
return nil
}