packer-cn/builder/common/config.go

120 lines
2.8 KiB
Go

package common
import (
"fmt"
"github.com/mitchellh/mapstructure"
"github.com/mitchellh/packer/packer"
"net/url"
"os"
"path/filepath"
"sort"
"strings"
)
// CheckUnusedConfig is a helper that makes sure that the there are no
// unused configuration keys, properly ignoring keys that don't matter.
func CheckUnusedConfig(md *mapstructure.Metadata) *packer.MultiError {
errs := make([]error, 0)
if md.Unused != nil && len(md.Unused) > 0 {
sort.Strings(md.Unused)
for _, unused := range md.Unused {
if unused != "type" && !strings.HasPrefix(unused, "packer_") {
errs = append(
errs, fmt.Errorf("Unknown configuration key: %s", unused))
}
}
}
if len(errs) > 0 {
return &packer.MultiError{errs}
}
return nil
}
// DecodeConfig is a helper that handles decoding raw configuration using
// mapstructure. It returns the metadata and any errors that may happen.
// If you need extra configuration for mapstructure, you should configure
// it manually and not use this helper function.
func DecodeConfig(target interface{}, raws ...interface{}) (*mapstructure.Metadata, error) {
var md mapstructure.Metadata
decoderConfig := &mapstructure.DecoderConfig{
Metadata: &md,
Result: target,
}
decoder, err := mapstructure.NewDecoder(decoderConfig)
if err != nil {
return nil, err
}
for _, raw := range raws {
err := decoder.Decode(raw)
if err != nil {
return nil, err
}
}
return &md, nil
}
// DownloadableURL processes a URL that may also be a file path and returns
// a completely valid URL. For example, the original URL might be "local/file.iso"
// which isn't a valid URL. DownloadableURL will return "file:///local/file.iso"
func DownloadableURL(original string) (string, error) {
url, err := url.Parse(original)
if err != nil {
return "", err
}
if url.Scheme == "" {
url.Scheme = "file"
}
if url.Scheme == "file" {
if _, err := os.Stat(url.Path); err != nil {
return "", err
}
url.Path, err = filepath.Abs(url.Path)
if err != nil {
return "", err
}
url.Path, err = filepath.EvalSymlinks(url.Path)
if err != nil {
return "", err
}
url.Path = filepath.Clean(url.Path)
}
// Make sure it is lowercased
url.Scheme = strings.ToLower(url.Scheme)
// This is to work around issue #5927. This can safely be removed once
// we distribute with a version of Go that fixes that bug.
//
// See: https://code.google.com/p/go/issues/detail?id=5927
if url.Path != "" && url.Path[0] != '/' {
url.Path = "/" + url.Path
}
// Verify that the scheme is something we support in our common downloader.
supported := []string{"file", "http", "https"}
found := false
for _, s := range supported {
if url.Scheme == s {
found = true
break
}
}
if !found {
return "", fmt.Errorf("Unsupported URL scheme: %s", url.Scheme)
}
return url.String(), nil
}