istio

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// Copyright Istio Authors
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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//     http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package translate
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import (
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	"gopkg.in/yaml.v2"
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	"istio.io/istio/operator/pkg/tpath"
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	"istio.io/istio/operator/pkg/util"
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)
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// YAMLTree takes an input tree inTreeStr, a partially constructed output tree outTreeStr, and a map of
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// translations of source-path:dest-path in pkg/tpath format. It returns an output tree with paths from the input
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// tree, translated and overlaid on the output tree.
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func YAMLTree(inTreeStr, outTreeStr string, translations map[string]string) (string, error) {
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	inTree := make(map[string]any)
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	if err := yaml.Unmarshal([]byte(inTreeStr), &inTree); err != nil {
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		return "", err
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	}
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	outTree := make(map[string]any)
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	if err := yaml.Unmarshal([]byte(outTreeStr), &outTree); err != nil {
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		return "", err
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	}
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	for inPath, translation := range translations {
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		path := util.PathFromString(inPath)
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		node, found, err := tpath.Find(inTree, path)
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		if err != nil {
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			return "", err
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		}
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		if !found {
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			continue
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		}
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		if err := tpath.MergeNode(outTree, util.PathFromString(translation), node); err != nil {
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			return "", err
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		}
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	}
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	outYAML, err := yaml.Marshal(outTree)
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	if err != nil {
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		return "", err
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	}
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	return string(outYAML), nil
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}
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