Add translation v35 to v34

go.mod

@@ -2,6 +2,8 @@ module github.com/coreos/ign-converter
 
 go 1.18
 
+replace github.com/coreos/ign-converter/translate/v34tov35 => ./translate/v35tov34
+
 require (
 	github.com/clarketm/json v1.17.1
 	github.com/coreos/ignition v0.35.0

translate/v35tov34/v35tov34.go

@@ -0,0 +1,97 @@
+// Copyright 2020 Red Hat, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package v35tov34
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/coreos/ignition/v2/config/translate"
+	"github.com/coreos/ignition/v2/config/v3_4/types"
+
+	old_types "github.com/coreos/ignition/v2/config/v3_5/types"
+	"github.com/coreos/ignition/v2/config/validate"
+)
+
+// Copy of github.com/coreos/ignition/v2/config/v3_4/translate/translate.go
+// with the types & old_types imports reversed (the referenced file translates
+// from 3.4 -> 3.5 but as a result only touches fields that are understood by
+// the 3.4 spec).
+func translateIgnition(old old_types.Ignition) (ret types.Ignition) {
+	// use a new translator so we don't recurse infinitely
+	translate.NewTranslator().Translate(&old, &ret)
+	ret.Version = types.MaxVersion.String()
+	return
+}
+func translateLuks(old old_types.Luks) (ret types.Luks) {
+	tr := translate.NewTranslator()
+	tr.AddCustomTranslator(translateTang)
+	tr.Translate(&old.Clevis, &ret.Clevis)
+	tr.Translate(&old.Device, &ret.Device)
+	tr.Translate(&old.KeyFile, &ret.KeyFile)
+	tr.Translate(&old.Label, &ret.Label)
+	tr.Translate(&old.Name, &ret.Name)
+	tr.Translate(&old.OpenOptions, &ret.OpenOptions)
+	tr.Translate(&old.Options, &ret.Options)
+	tr.Translate(&old.Discard, &ret.Discard)
+	tr.Translate(&old.UUID, &ret.UUID)
+	tr.Translate(&old.WipeVolume, &ret.WipeVolume)
+	return
+}
+func translateTang(old old_types.Tang) (ret types.Tang) {
+	tr := translate.NewTranslator()
+	tr.Translate(&old.Thumbprint, &ret.Thumbprint)
+	tr.Translate(&old.URL, &ret.URL)
+	return
+}
+func translateConfig(old old_types.Config) (ret types.Config) {
+	tr := translate.NewTranslator()
+	tr.AddCustomTranslator(translateIgnition)
+	tr.AddCustomTranslator(translateLuks)
+	tr.Translate(&old, &ret)
+	return
+}
+
+// end copied Ignition v3_5/translate block
+
+// Translate translates Ignition spec config v3.5 to spec v3.4
+func Translate(cfg old_types.Config) (types.Config, error) {
+	rpt := validate.ValidateWithContext(cfg, nil)
+	if rpt.IsFatal() {
+		return types.Config{}, fmt.Errorf("invalid input config:\n%s", rpt.String())
+	}
+
+	err := checkValue(reflect.ValueOf(cfg))
+	if err != nil {
+		return types.Config{}, err
+	}
+
+	res := translateConfig(cfg)
+
+	// Sanity check the returned config
+	oldrpt := validate.ValidateWithContext(res, nil)
+	if oldrpt.IsFatal() {
+		return types.Config{}, fmt.Errorf("converted spec has unexpected fatal error:\n%s", oldrpt.String())
+	}
+	return res, nil
+}
+
+func checkValue(v reflect.Value) error {
+	// v3.5 introduced Cex type
+	if v.Type() == reflect.TypeOf(old_types.Cex{}) {
+		return fmt.Errorf("invalid input config: 'Cex' type is not supported in spec v3.4")
+	}
+
+	return nil
+}