migrate

go.mod

module k8s.io/kubectx/migrate

go 1.13

require golang.org/x/tools v0.0.0-20200206010605-531cc8856e55

go.sum

golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg=
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
golang.org/x/tools v0.0.0-20200206010605-531cc8856e55 h1:kDk+lF3Oi/w2ujHLfJ8PCevhlfj7GFgH9A0dpxaJvYA=
golang.org/x/tools v0.0.0-20200206010605-531cc8856e55/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28=
golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

migrate.go

// Command migrate moves imports to the deprecated paths.
//
// Run with:
//
//   migrate **/*.go
package main

import (
	"bytes"
	"fmt"
	"go/ast"
	"go/format"
	"go/parser"
	"go/token"
	"io/ioutil"
	"os"
	"path"
	"strconv"
	"strings"

	"golang.org/x/tools/go/ast/astutil"
)

var migratedPkgs = map[string]string{
	"k8s.io/apiextensions-apiserver/pkg/client/clientset/clientset":   "k8s.io/apiextensions-apiserver/pkg/client/clientset/deprecated",
	"k8s.io/client-go/kubernetes":                                     "k8s.io/client-go/deprecated",
	"k8s.io/kube-aggregator/pkg/client/clientset_generated/clientset": "k8s.io/kube-aggregator/pkg/client/clientset_generated/deprecated",
	"k8s.io/metrics/pkg/client/clientset/versioned":                   "k8s.io/metrics/pkg/client/clientset/deprecated",
}

func main() {
	paths := os.Args[1:]
	for _, path := range paths {
		if err := migrate(path); err != nil {
		}
	}
}

type edit struct {
	start, end int
	data       []byte
}

func migrate(path string) error {
	src, err := ioutil.ReadFile(path)
	if err != nil {
		return err
	}

	fset := token.NewFileSet()
	f, err := parser.ParseFile(fset, path, src, parser.ImportsOnly)
	if err != nil {
		return err
	}

	var edits []edit
	for _, group := range astutil.Imports(fset, f) {
		for _, imp := range group {

			to, ok := toPath(fset, imp)
			if !ok {
				continue
			}

			var buf bytes.Buffer
			if err := format.Node(&buf, fset, to); err != nil {
				return err
			}

			edits = append(edits, edit{
				start: fset.File(f.Pos()).Offset(imp.Pos()),
				end:   fset.File(f.Pos()).Offset(imp.End()),
				data:  buf.Bytes(),
			})
		}
	}

	return applyEdits(path, src, edits)
}

func toPath(fset *token.FileSet, from *ast.ImportSpec) (*ast.ImportSpec, bool) {
	fromPath, err := strconv.Unquote(from.Path.Value)
	if err != nil {
		panic(err)
	}

	for src, target := range migratedPkgs {
		if strings.HasPrefix(fromPath, src) {
			base := strings.TrimPrefix(fromPath, src)
			toPath := path.Join(target, base)
			to := &ast.ImportSpec{
				Doc:  from.Doc,
				Name: from.Name,
				Path: &ast.BasicLit{
					Kind:  token.STRING,
					Value: strconv.Quote(toPath),
				},
				Comment: from.Comment,
			}
			if to.Name == nil && fromPath == src {
				to.Name = &ast.Ident{
					Name: path.Base(fromPath),
				}
			}

			fmt.Printf("%v: from=%q to=%q\n", fset.Position(from.Pos()), fromPath, toPath)
			return to, true
		}
	}

	return nil, false
}

func applyEdits(path string, src []byte, edits []edit) error {
	if len(edits) == 0 {
		return nil
	}

	var last int
	var buf bytes.Buffer
	for _, e := range edits {
		buf.Write(src[last:e.start])
		buf.Write(e.data)
		last = e.end
	}
	buf.Write(src[last:len(src)])

	return ioutil.WriteFile(path, buf.Bytes(), 0666)
}