org.springframework.boot.env.OriginTrackedYamlLoader Maven / Gradle / Ivy
/*
* Copyright 2012-2020 the original author or authors.
*
* 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
*
* https://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 org.springframework.boot.env;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import org.yaml.snakeyaml.DumperOptions;
import org.yaml.snakeyaml.LoaderOptions;
import org.yaml.snakeyaml.Yaml;
import org.yaml.snakeyaml.constructor.BaseConstructor;
import org.yaml.snakeyaml.constructor.Constructor;
import org.yaml.snakeyaml.constructor.SafeConstructor;
import org.yaml.snakeyaml.error.Mark;
import org.yaml.snakeyaml.nodes.CollectionNode;
import org.yaml.snakeyaml.nodes.MappingNode;
import org.yaml.snakeyaml.nodes.Node;
import org.yaml.snakeyaml.nodes.NodeTuple;
import org.yaml.snakeyaml.nodes.ScalarNode;
import org.yaml.snakeyaml.nodes.Tag;
import org.yaml.snakeyaml.representer.Representer;
import org.yaml.snakeyaml.resolver.Resolver;
import org.springframework.beans.factory.config.YamlProcessor;
import org.springframework.boot.origin.Origin;
import org.springframework.boot.origin.OriginTrackedValue;
import org.springframework.boot.origin.TextResourceOrigin;
import org.springframework.boot.origin.TextResourceOrigin.Location;
import org.springframework.core.io.Resource;
/**
* Class to load {@code .yml} files into a map of {@code String} to
* {@link OriginTrackedValue}.
*
* @author Madhura Bhave
* @author Phillip Webb
*/
class OriginTrackedYamlLoader extends YamlProcessor {
private final Resource resource;
OriginTrackedYamlLoader(Resource resource) {
this.resource = resource;
setResources(resource);
}
@Override
protected Yaml createYaml() {
LoaderOptions loaderOptions = new LoaderOptions();
loaderOptions.setAllowDuplicateKeys(false);
loaderOptions.setMaxAliasesForCollections(Integer.MAX_VALUE);
loaderOptions.setAllowRecursiveKeys(true);
return createYaml(loaderOptions);
}
private Yaml createYaml(LoaderOptions loaderOptions) {
BaseConstructor constructor = new OriginTrackingConstructor(loaderOptions);
Representer representer = new Representer();
DumperOptions dumperOptions = new DumperOptions();
LimitedResolver resolver = new LimitedResolver();
return new Yaml(constructor, representer, dumperOptions, loaderOptions, resolver);
}
List> load() {
final List> result = new ArrayList<>();
process((properties, map) -> result.add(getFlattenedMap(map)));
return result;
}
/**
* {@link Constructor} that tracks property origins.
*/
private class OriginTrackingConstructor extends SafeConstructor {
OriginTrackingConstructor(LoaderOptions loadingConfig) {
super(loadingConfig);
}
@Override
public Object getData() throws NoSuchElementException {
Object data = super.getData();
if (data instanceof CharSequence && ((CharSequence) data).length() == 0) {
return null;
}
return data;
}
@Override
protected Object constructObject(Node node) {
if (node instanceof CollectionNode && ((CollectionNode) node).getValue().isEmpty()) {
return constructTrackedObject(node, super.constructObject(node));
}
if (node instanceof ScalarNode) {
if (!(node instanceof KeyScalarNode)) {
return constructTrackedObject(node, super.constructObject(node));
}
}
if (node instanceof MappingNode) {
replaceMappingNodeKeys((MappingNode) node);
}
return super.constructObject(node);
}
private void replaceMappingNodeKeys(MappingNode node) {
node.setValue(node.getValue().stream().map(KeyScalarNode::get).collect(Collectors.toList()));
}
private Object constructTrackedObject(Node node, Object value) {
Origin origin = getOrigin(node);
return OriginTrackedValue.of(getValue(value), origin);
}
private Object getValue(Object value) {
return (value != null) ? value : "";
}
private Origin getOrigin(Node node) {
Mark mark = node.getStartMark();
Location location = new Location(mark.getLine(), mark.getColumn());
return new TextResourceOrigin(OriginTrackedYamlLoader.this.resource, location);
}
}
/**
* {@link ScalarNode} that replaces the key node in a {@link NodeTuple}.
*/
private static class KeyScalarNode extends ScalarNode {
KeyScalarNode(ScalarNode node) {
super(node.getTag(), node.getValue(), node.getStartMark(), node.getEndMark(), node.getScalarStyle());
}
static NodeTuple get(NodeTuple nodeTuple) {
Node keyNode = nodeTuple.getKeyNode();
Node valueNode = nodeTuple.getValueNode();
return new NodeTuple(KeyScalarNode.get(keyNode), valueNode);
}
private static Node get(Node node) {
if (node instanceof ScalarNode) {
return new KeyScalarNode((ScalarNode) node);
}
return node;
}
}
/**
* {@link Resolver} that limits {@link Tag#TIMESTAMP} tags.
*/
private static class LimitedResolver extends Resolver {
@Override
public void addImplicitResolver(Tag tag, Pattern regexp, String first) {
if (tag == Tag.TIMESTAMP) {
return;
}
super.addImplicitResolver(tag, regexp, first);
}
}
}