packer-cn/config.go

307 lines
8.9 KiB
Go

package main
import (
"encoding/json"
"fmt"
"io"
"log"
"os"
"os/exec"
"path/filepath"
"runtime"
"sort"
"strings"
"github.com/hashicorp/packer/command"
"github.com/hashicorp/packer/packer"
"github.com/hashicorp/packer/packer/plugin"
"github.com/kardianos/osext"
)
// PACKERSPACE is used to represent the spaces that separate args for a command
// without being confused with spaces in the path to the command itself.
const PACKERSPACE = "-PACKERSPACE-"
type config struct {
DisableCheckpoint bool `json:"disable_checkpoint"`
DisableCheckpointSignature bool `json:"disable_checkpoint_signature"`
PluginMinPort int
PluginMaxPort int
Builders packer.MapOfBuilder
Provisioners packer.MapOfProvisioner
PostProcessors packer.MapOfPostProcessor `json:"post-processors"`
}
// Decodes configuration in JSON format from the given io.Reader into
// the config object pointed to.
func decodeConfig(r io.Reader, c *config) error {
decoder := json.NewDecoder(r)
return decoder.Decode(c)
}
// Discover discovers plugins.
//
// Search the directory of the executable, then the plugins directory, and
// finally the CWD, in that order. Any conflicts will overwrite previously
// found plugins, in that order.
// Hence, the priority order is the reverse of the search order - i.e., the
// CWD has the highest priority.
func (c *config) Discover() error {
// If we are already inside a plugin process we should not need to
// discover anything.
if os.Getenv(plugin.MagicCookieKey) == plugin.MagicCookieValue {
return nil
}
// First, look in the same directory as the executable.
exePath, err := osext.Executable()
if err != nil {
log.Printf("[ERR] Error loading exe directory: %s", err)
} else {
if err := c.discoverExternalComponents(filepath.Dir(exePath)); err != nil {
return err
}
}
// Next, look in the plugins directory.
dir, err := packer.ConfigDir()
if err != nil {
log.Printf("[ERR] Error loading config directory: %s", err)
} else {
if err := c.discoverExternalComponents(filepath.Join(dir, "plugins")); err != nil {
return err
}
}
// Next, look in the CWD.
if err := c.discoverExternalComponents("."); err != nil {
return err
}
// Finally, try to use an internal plugin. Note that this will not override
// any previously-loaded plugins.
if err := c.discoverInternalComponents(); err != nil {
return err
}
return nil
}
// This is a proper packer.BuilderFunc that can be used to load packer.Builder
// implementations from the defined plugins.
func (c *config) StartBuilder(name string) (packer.Builder, error) {
log.Printf("Loading builder: %s\n", name)
return c.Builders.Start(name)
}
// This is a proper implementation of packer.HookFunc that can be used
// to load packer.Hook implementations from the defined plugins.
func (c *config) StarHook(name string) (packer.Hook, error) {
log.Printf("Loading hook: %s\n", name)
return c.pluginClient(name).Hook()
}
// This is a proper packer.PostProcessorFunc that can be used to load
// packer.PostProcessor implementations from defined plugins.
func (c *config) StartPostProcessor(name string) (packer.PostProcessor, error) {
log.Printf("Loading post-processor: %s", name)
return c.PostProcessors.Start(name)
}
// This is a proper packer.ProvisionerFunc that can be used to load
// packer.Provisioner implementations from defined plugins.
func (c *config) StartProvisioner(name string) (packer.Provisioner, error) {
log.Printf("Loading provisioner: %s\n", name)
return c.Provisioners.Start(name)
}
func (c *config) discoverExternalComponents(path string) error {
var err error
if !filepath.IsAbs(path) {
path, err = filepath.Abs(path)
if err != nil {
return err
}
}
externallyUsed := []string{}
pluginPaths, err := c.discoverSingle(filepath.Join(path, "packer-builder-*"))
if err != nil {
return err
}
for pluginName, pluginPath := range pluginPaths {
newPath := pluginPath // this needs to be stored in a new variable for the func below
c.Builders[pluginName] = func() (packer.Builder, error) {
return c.pluginClient(newPath).Builder()
}
externallyUsed = append(externallyUsed, pluginName)
}
if len(externallyUsed) > 0 {
sort.Strings(externallyUsed)
log.Printf("using external builders %v", externallyUsed)
externallyUsed = nil
}
pluginPaths, err = c.discoverSingle(filepath.Join(path, "packer-post-processor-*"))
if err != nil {
return err
}
for pluginName, pluginPath := range pluginPaths {
newPath := pluginPath // this needs to be stored in a new variable for the func below
c.PostProcessors[pluginName] = func() (packer.PostProcessor, error) {
return c.pluginClient(newPath).PostProcessor()
}
externallyUsed = append(externallyUsed, pluginName)
}
if len(externallyUsed) > 0 {
sort.Strings(externallyUsed)
log.Printf("using external post-processors %v", externallyUsed)
externallyUsed = nil
}
pluginPaths, err = c.discoverSingle(filepath.Join(path, "packer-provisioner-*"))
if err != nil {
return err
}
for pluginName, pluginPath := range pluginPaths {
newPath := pluginPath // this needs to be stored in a new variable for the func below
c.Provisioners[pluginName] = func() (packer.Provisioner, error) {
return c.pluginClient(newPath).Provisioner()
}
externallyUsed = append(externallyUsed, pluginName)
}
if len(externallyUsed) > 0 {
sort.Strings(externallyUsed)
log.Printf("using external provisioners %v", externallyUsed)
externallyUsed = nil
}
return nil
}
func (c *config) discoverSingle(glob string) (map[string]string, error) {
matches, err := filepath.Glob(glob)
if err != nil {
return nil, err
}
res := make(map[string]string)
prefix := filepath.Base(glob)
prefix = prefix[:strings.Index(prefix, "*")]
for _, match := range matches {
file := filepath.Base(match)
// One Windows, ignore any plugins that don't end in .exe.
// We could do a full PATHEXT parse, but this is probably good enough.
if runtime.GOOS == "windows" && strings.ToLower(filepath.Ext(file)) != ".exe" {
log.Printf(
"[DEBUG] Ignoring plugin match %s, no exe extension",
match)
continue
}
// If the filename has a ".", trim up to there
if idx := strings.Index(file, "."); idx >= 0 {
file = file[:idx]
}
// Look for foo-bar-baz. The plugin name is "baz"
pluginName := file[len(prefix):]
log.Printf("[DEBUG] Discovered plugin: %s = %s", pluginName, match)
res[pluginName] = match
}
return res, nil
}
func (c *config) discoverInternalComponents() error {
// Get the packer binary path
packerPath, err := osext.Executable()
if err != nil {
log.Printf("[ERR] Error loading exe directory: %s", err)
return err
}
for builder := range command.Builders {
builder := builder
_, found := (c.Builders)[builder]
if !found {
c.Builders[builder] = func() (packer.Builder, error) {
bin := fmt.Sprintf("%s%splugin%spacker-builder-%s",
packerPath, PACKERSPACE, PACKERSPACE, builder)
return c.pluginClient(bin).Builder()
}
}
}
for provisioner := range command.Provisioners {
provisioner := provisioner
_, found := (c.Provisioners)[provisioner]
if !found {
c.Provisioners[provisioner] = func() (packer.Provisioner, error) {
bin := fmt.Sprintf("%s%splugin%spacker-provisioner-%s",
packerPath, PACKERSPACE, PACKERSPACE, provisioner)
return c.pluginClient(bin).Provisioner()
}
}
}
for postProcessor := range command.PostProcessors {
postProcessor := postProcessor
_, found := (c.PostProcessors)[postProcessor]
if !found {
c.PostProcessors[postProcessor] = func() (packer.PostProcessor, error) {
bin := fmt.Sprintf("%s%splugin%spacker-post-processor-%s",
packerPath, PACKERSPACE, PACKERSPACE, postProcessor)
return c.pluginClient(bin).PostProcessor()
}
}
}
return nil
}
func (c *config) pluginClient(path string) *plugin.Client {
originalPath := path
// Check for special case using `packer plugin PLUGIN`
args := []string{}
if strings.Contains(path, PACKERSPACE) {
parts := strings.Split(path, PACKERSPACE)
path = parts[0]
args = parts[1:]
}
// First attempt to find the executable by consulting the PATH.
path, err := exec.LookPath(path)
if err != nil {
// If that doesn't work, look for it in the same directory
// as the `packer` executable (us).
log.Printf("Plugin could not be found at %s (%v). Checking same directory as executable.", originalPath, err)
exePath, err := osext.Executable()
if err != nil {
log.Printf("Couldn't get current exe path: %s", err)
} else {
log.Printf("Current exe path: %s", exePath)
path = filepath.Join(filepath.Dir(exePath), filepath.Base(originalPath))
}
}
// If everything failed, just use the original path and let the error
// bubble through.
if path == "" {
path = originalPath
}
log.Printf("Creating plugin client for path: %s", path)
var config plugin.ClientConfig
config.Cmd = exec.Command(path, args...)
config.Managed = true
config.MinPort = c.PluginMinPort
config.MaxPort = c.PluginMaxPort
return plugin.NewClient(&config)
}