Simple tool to migrate kardianos's govendor to golang's dep

govendor_to_dep.go

import (
	"io/ioutil"
	"log"
	"sort"

	vendorfile "github.com/kardianos/govendor/vendorfile"
)

func readFile(file string) (string, error) {
	data, err := ioutil.ReadFile(file)
	if err != nil {
		return "", err
	}

	return string(data), nil
}

func writeFile(file string, text string) error {
	err := ioutil.WriteFile(file, []byte(text), 0644)
	if err != nil {
		return err
	}

	return nil
}

type PackageSorter []*vendorfile.Package

func (pkgs PackageSorter) Len() int           { return len(pkgs) }
func (pkgs PackageSorter) Swap(i, j int)      { pkgs[i], pkgs[j] = pkgs[j], pkgs[i] }
func (pkgs PackageSorter) Less(i, j int) bool { return pkgs[i].Path < pkgs[j].Path }

func main() {
	// read from vendor.json
	vendorString, err := readFile("vendor/vendor.json")
	if err != nil {
		log.Println(err)
		return
	}

	vf := &vendorfile.File{}

	err = vf.Unmarshal(strings.NewReader(vendorString))
	if err != nil {
		log.Println(err)
		return
	}

	sort.Sort(PackageSorter(vf.Package))

	var output string
	for _, pkg := range vf.Package {
		output += "[[constraint]]\n"
		output += "  name = \"" + pkg.Path + "\"\n"
		if pkg.Revision != "" {
			output += "  revision = \"" + pkg.Revision + "\"\n"
		} else if pkg.Version != "" {
			output += "  version = \"" + pkg.Version + "\"\n"
		}
		output += "\n"
	}

	manifest := "Gopkg.toml"
	if err := writeFile(manifest, output); err != nil {
		log.Println(err)
		return
	}

	return
}