packer-cn/builder/azure/chroot/builder.go

453 lines
16 KiB
Go

//go:generate struct-markdown
// Package chroot is able to create an Azure managed image without requiring the
// launch of a new virtual machine for every build. It does this by attaching and
// mounting the root disk and chrooting into that directory.
// It then creates a managed image from that attached disk.
package chroot
import (
"context"
"errors"
"fmt"
"log"
"runtime"
"strings"
"github.com/hashicorp/packer/builder/amazon/chroot"
azcommon "github.com/hashicorp/packer/builder/azure/common"
"github.com/hashicorp/packer/builder/azure/common/client"
"github.com/hashicorp/packer/common"
"github.com/hashicorp/packer/helper/config"
"github.com/hashicorp/packer/helper/multistep"
"github.com/hashicorp/packer/packer"
"github.com/hashicorp/packer/template/interpolate"
"github.com/Azure/azure-sdk-for-go/profiles/latest/compute/mgmt/compute"
"github.com/Azure/go-autorest/autorest/azure"
"github.com/Azure/go-autorest/autorest/to"
)
// BuilderId is the unique ID for this builder
const BuilderId = "azure.chroot"
// Config is the configuration that is chained through the steps and settable
// from the template.
type Config struct {
common.PackerConfig `mapstructure:",squash"`
ClientConfig client.Config `mapstructure:",squash"`
// When set to `true`, starts with an empty, unpartitioned disk. Defaults to `false`.
FromScratch bool `mapstructure:"from_scratch"`
// Either a managed disk resource ID or a publisher:offer:sku:version specifier for plaform image sources.
Source string `mapstructure:"source" required:"true"`
sourceType sourceType
// How to run shell commands. This may be useful to set environment variables or perhaps run
// a command with sudo or so on. This is a configuration template where the `.Command` variable
// is replaced with the command to be run. Defaults to `{{.Command}}`.
CommandWrapper string `mapstructure:"command_wrapper"`
// A series of commands to execute after attaching the root volume and before mounting the chroot.
// This is not required unless using `from_scratch`. If so, this should include any partitioning
// and filesystem creation commands. The path to the device is provided by `{{.Device}}`.
PreMountCommands []string `mapstructure:"pre_mount_commands"`
// Options to supply the `mount` command when mounting devices. Each option will be prefixed with
// `-o` and supplied to the `mount` command ran by Packer. Because this command is ran in a shell,
// user discretion is advised. See this manual page for the `mount` command for valid file system specific options.
MountOptions []string `mapstructure:"mount_options"`
// The partition number containing the / partition. By default this is the first partition of the volume.
MountPartition string `mapstructure:"mount_partition"`
// The path where the volume will be mounted. This is where the chroot environment will be. This defaults
// to `/mnt/packer-amazon-chroot-volumes/{{.Device}}`. This is a configuration template where the `.Device`
// variable is replaced with the name of the device where the volume is attached.
MountPath string `mapstructure:"mount_path"`
// As `pre_mount_commands`, but the commands are executed after mounting the root device and before the
// extra mount and copy steps. The device and mount path are provided by `{{.Device}}` and `{{.MountPath}}`.
PostMountCommands []string `mapstructure:"post_mount_commands"`
// This is a list of devices to mount into the chroot environment. This configuration parameter requires
// some additional documentation which is in the "Chroot Mounts" section below. Please read that section
// for more information on how to use this.
ChrootMounts [][]string `mapstructure:"chroot_mounts"`
// Paths to files on the running Azure instance that will be copied into the chroot environment prior to
// provisioning. Defaults to `/etc/resolv.conf` so that DNS lookups work. Pass an empty list to skip copying
// `/etc/resolv.conf`. You may need to do this if you're building an image that uses systemd.
CopyFiles []string `mapstructure:"copy_files"`
// The name of the temporary disk that will be created in the resource group of the VM that Packer is
// running on. Will be generated if not set.
TemporaryOSDiskName string `mapstructure:"temporary_os_disk_name"`
// Try to resize the OS disk to this size on the first copy. Disks can only be englarged. If not specified,
// the disk will keep its original size. Required when using `from_scratch`
OSDiskSizeGB int32 `mapstructure:"os_disk_size_gb"`
// The [storage SKU](https://docs.microsoft.com/en-us/rest/api/compute/disks/createorupdate#diskstorageaccounttypes)
// to use for the OS Disk. Defaults to `Standard_LRS`.
OSDiskStorageAccountType string `mapstructure:"os_disk_storage_account_type"`
// The [cache type](https://docs.microsoft.com/en-us/rest/api/compute/images/createorupdate#cachingtypes)
// specified in the resulting image and for attaching it to the Packer VM. Defaults to `ReadOnly`
OSDiskCacheType string `mapstructure:"os_disk_cache_type"`
// If set to `true`, leaves the temporary disk behind in the Packer VM resource group. Defaults to `false`
OSDiskSkipCleanup bool `mapstructure:"os_disk_skip_cleanup"`
// The image to create using this build.
ImageResourceID string `mapstructure:"image_resource_id" required:"true"`
// The [Hyper-V generation type](https://docs.microsoft.com/en-us/rest/api/compute/images/createorupdate#hypervgenerationtypes).
// Defaults to `V1`.
ImageHyperVGeneration string `mapstructure:"image_hyperv_generation"`
ctx interpolate.Context
}
type sourceType string
const (
sourcePlatformImage sourceType = "PlatformImage"
sourceDisk sourceType = "Disk"
)
// GetContext implements ContextProvider to allow steps to use the config context
// for template interpolation
func (c *Config) GetContext() interpolate.Context {
return c.ctx
}
type Builder struct {
config Config
runner multistep.Runner
}
func (b *Builder) Prepare(raws ...interface{}) ([]string, error) {
b.config.ctx.Funcs = azcommon.TemplateFuncs
b.config.ctx.Funcs["vm"] = CreateVMMetadataTemplateFunc()
err := config.Decode(&b.config, &config.DecodeOpts{
Interpolate: true,
InterpolateContext: &b.config.ctx,
InterpolateFilter: &interpolate.RenderFilter{
Exclude: []string{
// these fields are interpolated in the steps,
// when more information is available
"command_wrapper",
"post_mount_commands",
"pre_mount_commands",
"mount_path",
},
},
}, raws...)
if err != nil {
return nil, err
}
var errs *packer.MultiError
var warns []string
// Defaults
err = b.config.ClientConfig.SetDefaultValues()
if err != nil {
return nil, err
}
if b.config.ChrootMounts == nil {
b.config.ChrootMounts = make([][]string, 0)
}
if len(b.config.ChrootMounts) == 0 {
b.config.ChrootMounts = [][]string{
{"proc", "proc", "/proc"},
{"sysfs", "sysfs", "/sys"},
{"bind", "/dev", "/dev"},
{"devpts", "devpts", "/dev/pts"},
{"binfmt_misc", "binfmt_misc", "/proc/sys/fs/binfmt_misc"},
}
}
// set default copy file if we're not giving our own
if b.config.CopyFiles == nil {
if !b.config.FromScratch {
b.config.CopyFiles = []string{"/etc/resolv.conf"}
}
}
if b.config.CommandWrapper == "" {
b.config.CommandWrapper = "{{.Command}}"
}
if b.config.MountPath == "" {
b.config.MountPath = "/mnt/packer-azure-chroot-disks/{{.Device}}"
}
if b.config.MountPartition == "" {
b.config.MountPartition = "1"
}
if b.config.TemporaryOSDiskName == "" {
if def, err := interpolate.Render("PackerTemp-{{timestamp}}", &b.config.ctx); err == nil {
b.config.TemporaryOSDiskName = def
} else {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("unable to render temporary disk name: %s", err))
}
}
if b.config.OSDiskStorageAccountType == "" {
b.config.OSDiskStorageAccountType = string(compute.PremiumLRS)
}
if b.config.OSDiskCacheType == "" {
b.config.OSDiskCacheType = string(compute.CachingTypesReadOnly)
}
if b.config.ImageHyperVGeneration == "" {
b.config.ImageHyperVGeneration = string(compute.V1)
}
// checks, accumulate any errors or warnings
if b.config.FromScratch {
if b.config.Source != "" {
errs = packer.MultiErrorAppend(
errs, errors.New("source cannot be specified when building from_scratch"))
}
if b.config.OSDiskSizeGB == 0 {
errs = packer.MultiErrorAppend(
errs, errors.New("os_disk_size_gb is required with from_scratch"))
}
if len(b.config.PreMountCommands) == 0 {
errs = packer.MultiErrorAppend(
errs, errors.New("pre_mount_commands is required with from_scratch"))
}
} else {
if _, err := client.ParsePlatformImageURN(b.config.Source); err == nil {
log.Println("Source is platform image:", b.config.Source)
b.config.sourceType = sourcePlatformImage
} else if id, err := azure.ParseResourceID(b.config.Source); err == nil &&
strings.EqualFold(id.Provider, "Microsoft.Compute") && strings.EqualFold(id.ResourceType, "disks") {
log.Println("Source is a disk resource ID:", b.config.Source)
b.config.sourceType = sourceDisk
} else {
errs = packer.MultiErrorAppend(
errs, fmt.Errorf("source: %q is not a valid platform image specifier, nor is it a disk resource ID", b.config.Source))
}
}
if err := checkDiskCacheType(b.config.OSDiskCacheType); err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("os_disk_cache_type: %v", err))
}
if err := checkStorageAccountType(b.config.OSDiskStorageAccountType); err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("os_disk_storage_account_type: %v", err))
}
if b.config.ImageResourceID == "" {
errs = packer.MultiErrorAppend(errs, errors.New("image_resource_id is required"))
} else {
r, err := azure.ParseResourceID(b.config.ImageResourceID)
if err != nil ||
!strings.EqualFold(r.Provider, "Microsoft.Compute") ||
!strings.EqualFold(r.ResourceType, "images") {
errs = packer.MultiErrorAppend(fmt.Errorf(
"image_resource_id: %q is not a valid image resource id", b.config.ImageResourceID))
}
}
if err := checkHyperVGeneration(b.config.ImageHyperVGeneration); err != nil {
errs = packer.MultiErrorAppend(errs, fmt.Errorf("image_hyperv_generation: %v", err))
}
if errs != nil {
return warns, errs
}
packer.LogSecretFilter.Set(b.config.ClientConfig.ClientSecret, b.config.ClientConfig.ClientJWT)
return warns, nil
}
func checkDiskCacheType(s string) interface{} {
for _, v := range compute.PossibleCachingTypesValues() {
if compute.CachingTypes(s) == v {
return nil
}
}
return fmt.Errorf("%q is not a valid value %v",
s, compute.PossibleCachingTypesValues())
}
func checkStorageAccountType(s string) interface{} {
for _, v := range compute.PossibleDiskStorageAccountTypesValues() {
if compute.DiskStorageAccountTypes(s) == v {
return nil
}
}
return fmt.Errorf("%q is not a valid value %v",
s, compute.PossibleDiskStorageAccountTypesValues())
}
func checkHyperVGeneration(s string) interface{} {
for _, v := range compute.PossibleHyperVGenerationValues() {
if compute.HyperVGeneration(s) == v {
return nil
}
}
return fmt.Errorf("%q is not a valid value %v",
s, compute.PossibleHyperVGenerationValues())
}
func (b *Builder) Run(ctx context.Context, ui packer.Ui, hook packer.Hook) (packer.Artifact, error) {
if runtime.GOOS != "linux" {
return nil, errors.New("the azure-chroot builder only works on Linux environments")
}
err := b.config.ClientConfig.FillParameters()
if err != nil {
return nil, fmt.Errorf("error setting Azure client defaults: %v", err)
}
azcli, err := client.New(b.config.ClientConfig, ui.Say)
if err != nil {
return nil, fmt.Errorf("error creating Azure client: %v", err)
}
wrappedCommand := func(command string) (string, error) {
ictx := b.config.ctx
ictx.Data = &struct{ Command string }{Command: command}
return interpolate.Render(b.config.CommandWrapper, &ictx)
}
// Setup the state bag and initial state for the steps
state := new(multistep.BasicStateBag)
state.Put("config", &b.config)
state.Put("hook", hook)
state.Put("ui", ui)
state.Put("azureclient", azcli)
state.Put("wrappedCommand", chroot.CommandWrapper(wrappedCommand))
info, err := azcli.MetadataClient().GetComputeInfo()
if err != nil {
log.Printf("MetadataClient().GetComputeInfo(): error: %+v", err)
err := fmt.Errorf(
"Error retrieving information ARM resource ID and location" +
"of the VM that Packer is running on.\n" +
"Please verify that Packer is running on a proper Azure VM.")
ui.Error(err.Error())
return nil, err
}
state.Put("instance", info)
// Build the steps
var steps []multistep.Step
if b.config.FromScratch {
steps = append(steps,
&StepCreateNewDisk{
SubscriptionID: info.SubscriptionID,
ResourceGroup: info.ResourceGroupName,
DiskName: b.config.TemporaryOSDiskName,
DiskSizeGB: b.config.OSDiskSizeGB,
DiskStorageAccountType: b.config.OSDiskStorageAccountType,
HyperVGeneration: b.config.ImageHyperVGeneration,
Location: info.Location,
})
} else {
switch b.config.sourceType {
case sourcePlatformImage:
if pi, err := client.ParsePlatformImageURN(b.config.Source); err == nil {
if strings.EqualFold(pi.Version, "latest") {
vmi, err := azcli.VirtualMachineImagesClient().GetLatest(ctx, pi.Publisher, pi.Offer, pi.Sku, info.Location)
if err != nil {
return nil, fmt.Errorf("error retieving latest version of %q: %v", b.config.Source, err)
}
pi.Version = to.String(vmi.Name)
log.Println("Resolved latest version of source image:", pi.Version)
}
steps = append(steps,
&StepCreateNewDisk{
SubscriptionID: info.SubscriptionID,
ResourceGroup: info.ResourceGroupName,
DiskName: b.config.TemporaryOSDiskName,
DiskSizeGB: b.config.OSDiskSizeGB,
DiskStorageAccountType: b.config.OSDiskStorageAccountType,
HyperVGeneration: b.config.ImageHyperVGeneration,
Location: info.Location,
PlatformImage: pi,
SkipCleanup: b.config.OSDiskSkipCleanup,
})
} else {
panic("Unknown image source: " + b.config.Source)
}
case sourceDisk:
steps = append(steps,
&StepVerifySourceDisk{
SourceDiskResourceID: b.config.Source,
SubscriptionID: info.SubscriptionID,
Location: info.Location,
},
&StepCreateNewDisk{
SubscriptionID: info.SubscriptionID,
ResourceGroup: info.ResourceGroupName,
DiskName: b.config.TemporaryOSDiskName,
DiskSizeGB: b.config.OSDiskSizeGB,
DiskStorageAccountType: b.config.OSDiskStorageAccountType,
HyperVGeneration: b.config.ImageHyperVGeneration,
SourceDiskResourceID: b.config.Source,
Location: info.Location,
SkipCleanup: b.config.OSDiskSkipCleanup,
})
default:
panic(fmt.Errorf("Unknown source type: %+q", b.config.sourceType))
}
}
steps = append(steps,
&StepAttachDisk{}, // uses os_disk_resource_id and sets 'device' in stateBag
&chroot.StepPreMountCommands{
Commands: b.config.PreMountCommands,
},
&StepMountDevice{
MountOptions: b.config.MountOptions,
MountPartition: b.config.MountPartition,
MountPath: b.config.MountPath,
},
&chroot.StepPostMountCommands{
Commands: b.config.PostMountCommands,
},
&chroot.StepMountExtra{
ChrootMounts: b.config.ChrootMounts,
},
&chroot.StepCopyFiles{
Files: b.config.CopyFiles,
},
&chroot.StepChrootProvision{},
&chroot.StepEarlyCleanup{},
&StepCreateImage{
ImageResourceID: b.config.ImageResourceID,
ImageOSState: string(compute.Generalized),
OSDiskCacheType: b.config.OSDiskCacheType,
OSDiskStorageAccountType: b.config.OSDiskStorageAccountType,
Location: info.Location,
},
)
// Run!
b.runner = common.NewRunner(steps, b.config.PackerConfig, ui)
b.runner.Run(ctx, state)
// If there was an error, return that
if rawErr, ok := state.GetOk("error"); ok {
return nil, rawErr.(error)
}
// Build the artifact and return it
artifact := &azcommon.Artifact{
Resources: []string{b.config.ImageResourceID},
BuilderIdValue: BuilderId,
}
return artifact, nil
}
var _ packer.Builder = &Builder{}