/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.logging.log4j.core.config.composite;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.logging.log4j.Level;
import org.apache.logging.log4j.core.Filter;
import org.apache.logging.log4j.core.config.AbstractConfiguration;
import org.apache.logging.log4j.core.config.Node;
import org.apache.logging.log4j.core.config.plugins.util.PluginManager;
import org.apache.logging.log4j.core.config.plugins.util.PluginType;
import org.apache.logging.log4j.core.filter.CompositeFilter;
/**
* The default merge strategy for composite configurations.
* <p>
* The default merge strategy performs the merge according to the following rules:
* <ol>
* <li>Aggregates the global configuration attributes with those in later configurations replacing those in previous
* configurations with the exception that the highest status level and the lowest monitorInterval greater than 0 will
* be used.</li>
* <li>Properties from all configurations are aggregated. Duplicate properties replace those in previous
* configurations.</li>
* <li>Filters are aggregated under a CompositeFilter if more than one Filter is defined. Since Filters are not named
* duplicates may be present.</li>
* <li>Scripts and ScriptFile references are aggregated. Duplicate definiations replace those in previous
* configurations.</li>
* <li>Appenders are aggregated. Appenders with the same name are replaced by those in later configurations, including
* all of the Appender's subcomponents.</li>
* <li>Loggers are all aggregated. Logger attributes are individually merged with duplicates being replaced by those
* in later configurations. Appender references on a Logger are aggregated with duplicates being replaced by those in
* later configurations. Filters on a Logger are aggregated under a CompositeFilter if more than one Filter is defined.
* Since Filters are not named duplicates may be present. Filters under Appender references included or discarded
* depending on whether their parent Appender reference is kept or discarded.</li>
* </ol>
*/
public class DefaultMergeStrategy implements MergeStrategy {
private static final String APPENDERS = "appenders";
private static final String PROPERTIES = "properties";
private static final String LOGGERS = "loggers";
private static final String SCRIPTS = "scripts";
private static final String FILTERS = "filters";
private static final String STATUS = "status";
private static final String NAME = "name";
private static final String REF = "ref";
/**
* Merge the root properties.
* @param rootNode The composite root node.
* @param configuration The configuration to merge.
*/
@Override
public void mergeRootProperties(final Node rootNode, final AbstractConfiguration configuration) {
for (final Map.Entry<String, String> attribute : configuration.getRootNode().getAttributes().entrySet()) {
boolean isFound = false;
for (final Map.Entry<String, String> targetAttribute : rootNode.getAttributes().entrySet()) {
if (targetAttribute.getKey().equalsIgnoreCase(attribute.getKey())) {
if (attribute.getKey().equalsIgnoreCase(STATUS)) {
final Level targetLevel = Level.getLevel(targetAttribute.getValue().toUpperCase());
final Level sourceLevel = Level.getLevel(attribute.getValue().toUpperCase());
if (targetLevel != null && sourceLevel != null) {
if (sourceLevel.isLessSpecificThan(targetLevel)) {
targetAttribute.setValue(attribute.getValue());
}
} else
if (sourceLevel != null) {
targetAttribute.setValue(attribute.getValue());
}
} else {
if (attribute.getKey().equalsIgnoreCase("monitorInterval")) {
final int sourceInterval = Integer.parseInt(attribute.getValue());
final int targetInterval = Integer.parseInt(targetAttribute.getValue());
if (targetInterval == 0 || sourceInterval < targetInterval) {
targetAttribute.setValue(attribute.getValue());
}
} else {
targetAttribute.setValue(attribute.getValue());
}
}
isFound = true;
}
}
if (!isFound) {
rootNode.getAttributes().put(attribute.getKey(), attribute.getValue());
}
}
}
/**
* Merge the source Configuration into the target Configuration.
*
* @param target The target node to merge into.
* @param source The source node.
* @param pluginManager The PluginManager.
*/
@Override
public void mergConfigurations(final Node target, final Node source, final PluginManager pluginManager) {
for (final Node sourceChildNode : source.getChildren()) {
final boolean isFilter = isFilterNode(sourceChildNode);
boolean isMerged = false;
for (final Node targetChildNode : target.getChildren()) {
if (isFilter) {
if (isFilterNode(targetChildNode)) {
updateFilterNode(target, targetChildNode, sourceChildNode, pluginManager);
isMerged = true;
break;
}
continue;
}
if (!targetChildNode.getName().equalsIgnoreCase(sourceChildNode.getName())) {
continue;
}
switch (targetChildNode.getName().toLowerCase()) {
case PROPERTIES:
case SCRIPTS:
case APPENDERS: {
for (final Node node : sourceChildNode.getChildren()) {
for (final Node targetNode : targetChildNode.getChildren()) {
if (targetNode.getAttributes().get(NAME).equals(node.getAttributes().get(NAME))) {
targetChildNode.getChildren().remove(targetNode);
break;
}
}
targetChildNode.getChildren().add(node);
}
isMerged = true;
break;
}
case LOGGERS: {
final Map<String, Node> targetLoggers = new HashMap<>();
for (final Node node : targetChildNode.getChildren()) {
targetLoggers.put(node.getName(), node);
}
for (final Node node : sourceChildNode.getChildren()) {
final Node targetNode = getLoggerNode(targetChildNode, node.getAttributes().get(NAME));
final Node loggerNode = new Node(targetChildNode, node.getName(), node.getType());
if (targetNode != null) {
targetNode.getAttributes().putAll(node.getAttributes());
for (final Node sourceLoggerChild : node.getChildren()) {
if (isFilterNode(sourceLoggerChild)) {
boolean foundFilter = false;
for (final Node targetChild : targetNode.getChildren()) {
if (isFilterNode(targetChild)) {
updateFilterNode(loggerNode, targetChild, sourceLoggerChild,
pluginManager);
foundFilter = true;
break;
}
}
if (!foundFilter) {
final Node childNode = new Node(loggerNode, sourceLoggerChild.getName(),
sourceLoggerChild.getType());
targetNode.getChildren().add(childNode);
}
} else {
final Node childNode = new Node(loggerNode, sourceLoggerChild.getName(),
sourceLoggerChild.getType());
childNode.getAttributes().putAll(sourceLoggerChild.getAttributes());
childNode.getChildren().addAll(sourceLoggerChild.getChildren());
if (childNode.getName().equalsIgnoreCase("AppenderRef")) {
for (final Node targetChild : targetNode.getChildren()) {
if (isSameReference(targetChild, childNode)) {
targetNode.getChildren().remove(targetChild);
break;
}
}
} else {
for (final Node targetChild : targetNode.getChildren()) {
if (isSameName(targetChild, childNode)) {
targetNode.getChildren().remove(targetChild);
break;
}
}
}
targetNode.getChildren().add(childNode);
}
}
} else {
loggerNode.getAttributes().putAll(node.getAttributes());
loggerNode.getChildren().addAll(node.getChildren());
targetChildNode.getChildren().add(loggerNode);
}
}
isMerged = true;
break;
}
default: {
targetChildNode.getChildren().addAll(sourceChildNode.getChildren());
isMerged = true;
break;
}
}
}
if (!isMerged) {
if (sourceChildNode.getName().equalsIgnoreCase("Properties")) {
target.getChildren().add(0, sourceChildNode);
} else {
target.getChildren().add(sourceChildNode);
}
}
}
}
private Node getLoggerNode(final Node parentNode, final String name) {
for (final Node node : parentNode.getChildren()) {
final String nodeName = node.getAttributes().get(NAME);
if (name == null && nodeName == null) {
return node;
}
if (nodeName != null && nodeName.equals(name)) {
return node;
}
}
return null;
}
private void updateFilterNode(final Node target, final Node targetChildNode, final Node sourceChildNode,
final PluginManager pluginManager) {
if (CompositeFilter.class.isAssignableFrom(targetChildNode.getType().getPluginClass())) {
final Node node = new Node(targetChildNode, sourceChildNode.getName(), sourceChildNode.getType());
node.getChildren().addAll(sourceChildNode.getChildren());
node.getAttributes().putAll(sourceChildNode.getAttributes());
targetChildNode.getChildren().add(node);
} else {
final PluginType pluginType = pluginManager.getPluginType(FILTERS);
final Node filtersNode = new Node(targetChildNode, FILTERS, pluginType);
final Node node = new Node(filtersNode, sourceChildNode.getName(), sourceChildNode.getType());
node.getAttributes().putAll(sourceChildNode.getAttributes());
final List<Node> children = filtersNode.getChildren();
children.add(targetChildNode);
children.add(node);
final List<Node> nodes = target.getChildren();
nodes.remove(targetChildNode);
nodes.add(filtersNode);
}
}
private boolean isFilterNode(final Node node) {
return Filter.class.isAssignableFrom(node.getType().getPluginClass());
}
private boolean isSameName(final Node node1, final Node node2) {
final String value = node1.getAttributes().get(NAME);
return value != null && value.toLowerCase().equals(node2.getAttributes().get(NAME).toLowerCase());
}
private boolean isSameReference(final Node node1, final Node node2) {
final String value = node1.getAttributes().get(REF);
return value != null && value.toLowerCase().equals(node2.getAttributes().get(REF).toLowerCase());
}
}