iSharkFly-Docs
/
packer-cn
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

First version of reworked snapshot implementation

This commit is contained in:
Thomas Meckel 2019-03-17 20:50:13 +01:00 committed by Thomas Meckel
parent a6074894f1
commit 092e32fe9e
7 changed files with 305 additions and 137 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
builder/virtualbox/common/driver.go
View File

@ -42,6 +42,7 @@ type Driver interface {
SuppressMessages() error
// VBoxManage executes the given VBoxManage command
// and returns the stdout channel as string
VBoxManage(...string) error
// Verify checks to make sure that this driver should function
@ -52,26 +53,24 @@ type Driver interface {
// Version reads the version of VirtualBox that is installed.
Version() (string, error)
//
// LoadSnapshots Loads all defined snapshots for a vm.
// if no snapshots are defined nil will be returned
LoadSnapshots(string) (*VBoxSnapshot, error)
// CreateSnapshot Creates a snapshot for a vm with a given name
CreateSnapshot(string, string) error
//
// HasSnapshots tests if a vm has snapshots
HasSnapshots(string) (bool, error)
//
GetCurrentSnapshot(string) (string, error)
// GetCurrentSnapshot Returns the current snapshot for a vm
GetCurrentSnapshot(string) (*VBoxSnapshot, error)
//
SetSnapshot(string, string) error
// SetSnapshot sets the for a vm
SetSnapshot(string, *VBoxSnapshot) error
//
DeleteSnapshot(string, string) error
//
SnapshotExists(string, string) (bool, error)
//
GetParentSnapshot(string, string) (string, error)
// DeleteSnapshot deletes the specified snapshot from a vm
DeleteSnapshot(string, *VBoxSnapshot) error
}
func NewDriver() (Driver, error) {

171
builder/virtualbox/common/driver_4_2.go
View File

@ -1,6 +1,7 @@
package common
import (
"bufio"
"bytes"
"context"
"fmt"
@ -11,8 +12,8 @@ import (
"strings"
"time"
"github.com/golang-collections/collections/stack"
versionUtil "github.com/hashicorp/go-version"
packer "github.com/hashicorp/packer/common"
)
@ -178,6 +179,11 @@ func (d *VBox42Driver) SuppressMessages() error {
}
func (d *VBox42Driver) VBoxManage(args ...string) error {
_, err := d.VBoxManageWithOutput(args...)
return err
}
func (d *VBox42Driver) VBoxManageWithOutput(args ...string) (string, error) {
var stdout, stderr bytes.Buffer
log.Printf("Executing VBoxManage: %#v", args)
@ -205,7 +211,7 @@ func (d *VBox42Driver) VBoxManage(args ...string) error {
log.Printf("stdout: %s", stdoutString)
log.Printf("stderr: %s", stderrString)
return err
return stdoutString, err
}
func (d *VBox42Driver) Verify() error {
@ -243,89 +249,133 @@ func (d *VBox42Driver) Version() (string, error) {
// LoadSnapshots load the snapshots for a VM instance
func (d *VBox42Driver) LoadSnapshots(vmName string) (*VBoxSnapshot, error) {
return nil, nil
if vmName == "" {
panic("Argument empty exception: vmName")
}
log.Printf("Executing LoadSnapshots: VM: %s", vmName)
stdoutString, err := d.VBoxManageWithOutput("snapshot", vmName, "list", "--machinereadable")
if nil != err {
return nil, err
}
var rootNode *VBoxSnapshot
if stdoutString != "This machine does not have any snapshots" {
scanner := bufio.NewScanner(strings.NewReader(stdoutString))
SnapshotNamePartsRe := regexp.MustCompile("Snapshot(?P<Type>Name|UUID)(?P<Path>(-[1-9]+)*)=\"(?P<Value>[^\"]*)\"")
var currentIndicator string
parentStack := stack.New()
var node *VBoxSnapshot
for scanner.Scan() {
txt := scanner.Text()
idx := strings.Index(txt, "=")
if idx > 0 {
if strings.HasPrefix(txt, "Current") {
node.IsCurrent = true
} else {
matches := SnapshotNamePartsRe.FindStringSubmatch(txt)
log.Printf("************ Snapshot %s name parts", txt)
log.Printf("Matches %#v\n", matches)
log.Printf("Node %s\n", matches[0])
log.Printf("Type %s\n", matches[1])
log.Printf("Path %s\n", matches[2])
log.Printf("Leaf %s\n", matches[3])
log.Printf("Value %s\n", matches[4])
if matches[1] == "Name" {
if nil == rootNode {
node = new(VBoxSnapshot)
rootNode = node
currentIndicator = matches[2]
} else {
pathLenCur := strings.Count(currentIndicator, "-")
pathLen := strings.Count(matches[2], "-")
if pathLen > pathLenCur {
currentIndicator = matches[2]
parentStack.Push(node)
} else if pathLen < pathLenCur {
for i := 0; i < pathLenCur-1; i++ {
parentStack.Pop()
}
}
node = new(VBoxSnapshot)
parent := parentStack.Peek().(*VBoxSnapshot)
if nil != parent {
parent.Children = append(parent.Children, node)
}
}
node.Name = matches[4]
} else if matches[1] == "UUID" {
node.UUID = matches[4]
}
}
} else {
log.Printf("Invalid key,value pair [%s]", txt)
}
}
}
return rootNode, nil
}
func (d *VBox42Driver) CreateSnapshot(vmname string, snapshotName string) error {
if vmname == "" {
panic("Argument empty exception: vmname")
}
log.Printf("Executing CreateSnapshot: VM: %s, SnapshotName %s", vmname, snapshotName)
return d.VBoxManage("snapshot", vmname, "take", snapshotName)
}
func (d *VBox42Driver) HasSnapshots(vmname string) (bool, error) {
if vmname == "" {
panic("Argument empty exception: vmname")
}
log.Printf("Executing HasSnapshots: VM: %s", vmname)
var stdout, stderr bytes.Buffer
var hasSnapshots = false
cmd := exec.Command(d.VBoxManagePath, "snapshot", vmname, "list", "--machinereadable")
cmd.Stdout = &stdout
cmd.Stderr = &stderr
err := cmd.Run()
stdoutString := strings.TrimSpace(stdout.String())
stderrString := strings.TrimSpace(stderr.String())
if _, ok := err.(*exec.ExitError); ok {
if stdoutString != "This machine does not have any snapshots" {
err = fmt.Errorf("VBoxManage error: %s", stderrString)
sn, err := d.LoadSnapshots(vmname)
if nil != err {
return false, err
}
} else {
hasSnapshots = true
return nil != sn, nil
}
return hasSnapshots, err
func (d *VBox42Driver) GetCurrentSnapshot(vmname string) (*VBoxSnapshot, error) {
if vmname == "" {
panic("Argument empty exception: vmname")
}
func (d *VBox42Driver) GetCurrentSnapshot(vmname string) (string, error) {
log.Printf("Executing GetCurrentSnapshot: VM: %s", vmname)
var stdout, stderr bytes.Buffer
cmd := exec.Command(d.VBoxManagePath, "snapshot", vmname, "list", "--machinereadable")
cmd.Stdout = &stdout
cmd.Stderr = &stderr
err := cmd.Run()
stdoutString := strings.TrimSpace(stdout.String())
stderrString := strings.TrimSpace(stderr.String())
if _, ok := err.(*exec.ExitError); ok {
if stdoutString == "This machine does not have any snapshots" {
return "", nil
} else {
return "", (fmt.Errorf("VBoxManage error: %s", stderrString))
sn, err := d.LoadSnapshots(vmname)
if nil != err {
return nil, err
}
return sn.GetCurrentSnapshot(), nil
}
CurrentSnapshotNameRe := regexp.MustCompile("CurrentSnapshotName=\"(?P<snapshotName>[^\"]*)\"")
for _, line := range strings.Split(stdout.String(), "\n") {
result := CurrentSnapshotNameRe.FindStringSubmatch(line)
if len(result) > 1 {
return result[1], nil
func (d *VBox42Driver) SetSnapshot(vmname string, sn *VBoxSnapshot) error {
if vmname == "" {
panic("Argument empty exception: vmname")
}
if nil == sn {
panic("Argument null exception: sn")
}
log.Printf("Executing SetSnapshot: VM: %s, SnapshotName %s", vmname, sn.UUID)
return d.VBoxManage("snapshot", vmname, "restore", sn.UUID)
}
return "", (fmt.Errorf("VBoxManage unable to find current snapshot name"))
}
func (d *VBox42Driver) SetSnapshot(vmname string, snapshotName string) error {
log.Printf("Executing SetSnapshot: VM: %s, SnapshotName %s", vmname, snapshotName)
var err error
if snapshotName == "" {
err = d.VBoxManage("snapshot", vmname, "restorecurrent")
} else {
err = d.VBoxManage("snapshot", vmname, "restore", snapshotName)
}
return err
}
func (d *VBox42Driver) DeleteSnapshot(vmname string, snapshotName string) error {
return d.VBoxManage("snapshot", vmname, "delete", snapshotName)
func (d *VBox42Driver) DeleteSnapshot(vmname string, sn *VBoxSnapshot) error {
if vmname == "" {
panic("Argument empty exception: vmname")
}
if nil == sn {
panic("Argument null exception: sn")
}
log.Printf("Executing DeleteSnapshot: VM: %s, SnapshotName %s", vmname, sn.UUID)
return d.VBoxManage("snapshot", vmname, "delete", sn.UUID)
}
/*
func (d *VBox42Driver) SnapshotExists(vmname string, snapshotName string) (bool, error) {
log.Printf("Executing SnapshotExists: VM %s, SnapshotName %s", vmname, snapshotName)
@ -412,3 +462,4 @@ func (d *VBox42Driver) GetParentSnapshot(vmname string, snapshotName string) (st
}
return "", nil
}
*/

116
builder/virtualbox/common/snapshot.go
View File

@ -1,15 +1,127 @@
package common
import (
"strings"
)
// VBoxSnapshot stores the hierarchy of snapshots for a VM instance
type VBoxSnapshot struct {
Name string
UUID string
IsCurrent bool
Parent *VBoxSnapshot // nil if topmost (root) snapshot
Children []VBoxSnapshot
Children []*VBoxSnapshot
}
// IsChildOf verifies if the current snaphot is a child of the passed as argument
func (sn *VBoxSnapshot) IsChildOf(candidate *VBoxSnapshot) bool {
return false
if nil == candidate {
panic("Missing parameter value: candidate")
}
node := sn
for nil != node {
if candidate.UUID == node.UUID {
break
}
node = node.Parent
}
return nil != node
}
// the walker uses a channel to return nodes from a snapshot tree in breadth approach
func walk(sn *VBoxSnapshot, ch chan *VBoxSnapshot) {
if nil == sn {
return
}
if 0 < len(sn.Children) {
for _, child := range sn.Children {
walk(child, ch)
}
} else {
ch <- sn
}
}
func walker(sn *VBoxSnapshot) <-chan *VBoxSnapshot {
if nil == sn {
panic("Argument null exception: sn")
}
ch := make(chan *VBoxSnapshot)
go func() {
walk(sn, ch)
close(ch)
}()
return ch
}
// GetRoot returns the top-most (root) snapshot for a given snapshot
func (sn *VBoxSnapshot) GetRoot() *VBoxSnapshot {
if nil == sn {
panic("Argument null exception: sn")
}
node := sn
for nil != node.Parent {
node = node.Parent
}
return node
}
// GetSnapshotsByName find all snapshots with a given name
func (sn *VBoxSnapshot) GetSnapshotsByName(name string) []*VBoxSnapshot {
var result []*VBoxSnapshot
root := sn.GetRoot()
ch := walker(root)
for {
node, ok := <-ch
if !ok {
panic("Internal channel error while traversing the snapshot tree")
}
if strings.EqualFold(node.Name, name) {
result = append(result, node)
}
}
return result
}
// GetSnapshotByUUID returns a snapshot by it's UUID
func (sn *VBoxSnapshot) GetSnapshotByUUID(uuid string) *VBoxSnapshot {
root := sn.GetRoot()
ch := walker(root)
for {
node, ok := <-ch
if !ok {
panic("Internal channel error while traversing the snapshot tree")
}
if strings.EqualFold(node.UUID, uuid) {
return node
}
}
return nil
}
// GetCurrentSnapshot returns the currently attached snapshot
func (sn *VBoxSnapshot) GetCurrentSnapshot() *VBoxSnapshot {
root := sn.GetRoot()
ch := walker(root)
for {
node, ok := <-ch
if !ok {
panic("Internal channel error while traversing the snapshot tree")
}
if node.IsCurrent {
return node
}
}
return nil
}
func (sn *VBoxSnapshot) GetChildWithName(name string) *VBoxSnapshot {
for _, child := range sn.Children {
if child.Name == name {
return child
}
}
return nil
}

3
builder/virtualbox/vm/builder.go
View File

@ -32,7 +32,7 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
// Run executes a Packer build and returns a packer.Artifact representing
// a VirtualBox appliance.
func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packer.Artifact, error) {
func (b *Builder) Run(ui packer.Ui, hook packer.Hook) (packer.Artifact, error) {
// Create the driver that we'll use to communicate with VirtualBox
driver, err := vboxcommon.NewDriver()
if err != nil {
@ -44,7 +44,6 @@ func (b *Builder) Run(ui packer.Ui, hook packer.Hook, cache packer.Cache) (packe
state.Put("config", b.config)
state.Put("debug", b.config.PackerDebug)
state.Put("driver", driver)
state.Put("cache", cache)
state.Put("hook", hook)
state.Put("ui", ui)

56
builder/virtualbox/vm/config.go
View File

@ -2,6 +2,7 @@ package vm
import (
"fmt"
"log"
"strings"
vboxcommon "github.com/hashicorp/packer/builder/virtualbox/common"
@ -128,52 +129,39 @@ func NewConfig(raws ...interface{}) (*Config, []string, error) {
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed creating VirtualBox driver: %s", err))
} else {
if c.AttachSnapshot != "" {
snapshotExists, err := driver.SnapshotExists(c.VMName, c.AttachSnapshot)
snapshotTree, err := driver.LoadSnapshots(c.VMName)
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed to check for snapshot: %s with VM %s ; Error: %s", c.AttachSnapshot, c.VMName, err))
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed creating VirtualBox driver: %s", err))
} else {
if !snapshotExists {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Snapshot %s does not exist on with VM %s", c.AttachSnapshot, c.VMName))
if c.AttachSnapshot != "" && c.TargetSnapshot != "" && c.AttachSnapshot == c.TargetSnapshot {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Attach snapshot %s and target snapshot %s cannot be the same", c.AttachSnapshot, c.TargetSnapshot))
}
attachSnapshot := snapshotTree.GetCurrentSnapshot()
if c.AttachSnapshot != "" {
snapshots := snapshotTree.GetSnapshotsByName(c.AttachSnapshot)
if 0 >= len(snapshots) {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Snapshot %s does not exist on with VM %s", c.AttachSnapshot, c.VMName))
} else if 1 < len(snapshots) {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Multiple Snapshots %s exist on with VM %s", c.AttachSnapshot, c.VMName))
} else {
attachSnapshot = snapshots[0]
}
}
if c.TargetSnapshot != "" {
snapshotExists, err := driver.SnapshotExists(c.VMName, c.TargetSnapshot)
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed to check for snapshot: %s", err))
} else {
if snapshotExists {
parent, err := driver.GetParentSnapshot(c.VMName, c.TargetSnapshot)
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed to get parent for snapshot %s: %s", c.TargetSnapshot, err))
return nil, warnings, errs
} else {
var selfSnapshotName string
if "" != c.AttachSnapshot {
selfSnapshotName = c.AttachSnapshot
} else {
currentSnapshot, err := driver.GetCurrentSnapshot(c.VMName)
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed to get current snapshot for VM %s: %s", c.VMName, err))
return nil, warnings, errs
snapshots := snapshotTree.GetSnapshotsByName(c.TargetSnapshot)
if 0 >= len(snapshots) {
isChild := false
for _, snapshot := range snapshots {
log.Printf("Checking if target snaphot %v is child of %s")
isChild = nil != snapshot.Parent && snapshot.Parent.UUID == attachSnapshot.UUID
}
selfSnapshotName = currentSnapshot
}
selfSnapshotParent, err := driver.GetParentSnapshot(c.VMName, selfSnapshotName)
if err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Failed to get parent for snapshot %s: %s", selfSnapshotName, err))
} else if parent != selfSnapshotName {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Target snapshot %s already exists and is not a direct child of %s", c.TargetSnapshot, selfSnapshotParent))
if !isChild {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Target snapshot %s already exists and is not a direct child of %s", c.TargetSnapshot, attachSnapshot.Name))
}
}
}
}
}
if c.AttachSnapshot != "" && c.TargetSnapshot != "" && c.AttachSnapshot == c.TargetSnapshot {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("Attach snapshot %s and target snapshot %s cannot be the same", c.AttachSnapshot, c.TargetSnapshot))
}
}
// Check for any errors.
if errs != nil && len(errs.Errors) > 0 {
return nil, warnings, errs

12
builder/virtualbox/vm/step_create_snapshot.go
View File

@ -22,15 +22,19 @@ func (s *StepCreateSnapshot) Run(_ context.Context, state multistep.StateBag) mu
if s.TargetSnapshot != "" {
time.Sleep(10 * time.Second) // Wait after the Vm has been shutdown, otherwise creating the snapshot might make the VM unstartable
ui.Say(fmt.Sprintf("Creating snapshot %s on virtual machine %s", s.TargetSnapshot, s.Name))
snapshotExists, err := driver.SnapshotExists(s.Name, s.TargetSnapshot)
snapshotTree, err := driver.LoadSnapshots(s.Name)
if err != nil {
err = fmt.Errorf("Failed to check for snapshot: %s", err)
err = fmt.Errorf("Failed to load snapshots for VM %s: %s", s.Name, err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
} else if snapshotExists {
}
currentSnapshot := snapshotTree.GetCurrentSnapshot()
targetSnapshot := currentSnapshot.GetChildWithName(s.TargetSnapshot)
if nil != targetSnapshot {
log.Printf("Deleting existing target snapshot %s", s.TargetSnapshot)
err = driver.DeleteSnapshot(s.Name, s.TargetSnapshot)
err = driver.DeleteSnapshot(s.Name, targetSnapshot)
if nil != err {
err = fmt.Errorf("Unable to delete snapshot %s from VM %s: %s", s.TargetSnapshot, s.Name, err)
state.Put("error", err)

43
builder/virtualbox/vm/step_set_snapshot.go
View File

@ -19,31 +19,37 @@ type StepSetSnapshot struct {
func (s *StepSetSnapshot) Run(_ context.Context, state multistep.StateBag) multistep.StepAction {
driver := state.Get("driver").(vboxcommon.Driver)
ui := state.Get("ui").(packer.Ui)
hasSnapshots, err := driver.HasSnapshots(s.Name)
snapshotTree, err := driver.LoadSnapshots(s.Name)
if err != nil {
err := fmt.Errorf("Error checking for snapshots VM: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
} else if hasSnapshots {
currentSnapshot, err := driver.GetCurrentSnapshot(s.Name)
if err != nil {
err := fmt.Errorf("Unable to get current snapshot for VM: %s", err)
err := fmt.Errorf("Error loading snapshots for VM: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
s.revertToSnapshot = currentSnapshot
}
if s.AttachSnapshot != "" {
if !hasSnapshots {
if nil == snapshotTree {
err := fmt.Errorf("Unable to attach snapshot on VM %s when no snapshots exist", s.Name)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
currentSnapshot := snapshotTree.GetCurrentSnapshot()
s.revertToSnapshot = currentSnapshot.UUID
ui.Say(fmt.Sprintf("Attaching snapshot %s on virtual machine %s", s.AttachSnapshot, s.Name))
err = driver.SetSnapshot(s.Name, s.AttachSnapshot)
candidateSnapshots := snapshotTree.GetSnapshotsByName(s.AttachSnapshot)
if 0 <= len(candidateSnapshots) {
err := fmt.Errorf("Snapshot %s not found on VM %s", s.AttachSnapshot, s.Name)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
} else if 1 > len(candidateSnapshots) {
err := fmt.Errorf("More than one Snapshot %s found on VM %s", s.AttachSnapshot, s.Name)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
} else {
err = driver.SetSnapshot(s.Name, candidateSnapshots[0])
if err != nil {
err := fmt.Errorf("Unable to set snapshot for VM: %s", err)
state.Put("error", err)
@ -51,6 +57,7 @@ func (s *StepSetSnapshot) Run(_ context.Context, state multistep.StateBag) multi
return multistep.ActionHalt
}
}
}
return multistep.ActionContinue
}
@ -63,7 +70,15 @@ func (s *StepSetSnapshot) Cleanup(state multistep.StateBag) {
return
} else {
ui.Say(fmt.Sprintf("Reverting to snapshot %s on virtual machine %s", s.revertToSnapshot, s.Name))
err := driver.SetSnapshot(s.Name, s.revertToSnapshot)
snapshotTree, err := driver.LoadSnapshots(s.Name)
revertTo := snapshotTree.GetSnapshotByUUID(s.revertToSnapshot)
if nil == revertTo {
err := fmt.Errorf("Snapshot with UUID %s not found for VM %s", s.revertToSnapshot, s.Name)
state.Put("error", err)
ui.Error(err.Error())
return
}
err = driver.SetSnapshot(s.Name, revertTo)
if err != nil {
err := fmt.Errorf("Unable to set snapshot for VM: %s", err)
state.Put("error", err)