Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.config.composite;
018
019import java.util.HashMap;
020import java.util.List;
021import java.util.Map;
022import java.util.Objects;
023
024import org.apache.logging.log4j.Level;
025import org.apache.logging.log4j.core.Filter;
026import org.apache.logging.log4j.core.config.AbstractConfiguration;
027import org.apache.logging.log4j.core.config.Node;
028import org.apache.logging.log4j.core.config.plugins.util.PluginManager;
029import org.apache.logging.log4j.core.config.plugins.util.PluginType;
030import org.apache.logging.log4j.core.filter.CompositeFilter;
031
032/**
033 * The default merge strategy for composite configurations.
034 * <p>
035 * The default merge strategy performs the merge according to the following rules:
036 * <ol>
037 * <li>Aggregates the global configuration attributes with those in later configurations replacing those in previous
038 * configurations with the exception that the highest status level and the lowest monitorInterval greater than 0 will
039 * be used.</li>
040 * <li>Properties from all configurations are aggregated. Duplicate properties replace those in previous
041 * configurations.</li>
042 * <li>Filters are aggregated under a CompositeFilter if more than one Filter is defined. Since Filters are not named
043 * duplicates may be present.</li>
044 * <li>Scripts and ScriptFile references are aggregated. Duplicate definiations replace those in previous
045 * configurations.</li>
046 * <li>Appenders are aggregated. Appenders with the same name are replaced by those in later configurations, including
047 * all of the Appender's subcomponents.</li>
048 * <li>Loggers are all aggregated. Logger attributes are individually merged with duplicates being replaced by those
049 * in later configurations. Appender references on a Logger are aggregated with duplicates being replaced by those in
050 * later configurations. Filters on a Logger are aggregated under a CompositeFilter if more than one Filter is defined.
051 * Since Filters are not named duplicates may be present. Filters under Appender references included or discarded
052 * depending on whether their parent Appender reference is kept or discarded.</li>
053 * </ol>
054 */
055public class DefaultMergeStrategy implements MergeStrategy {
056
057    private static final String APPENDERS = "appenders";
058    private static final String PROPERTIES = "properties";
059    private static final String LOGGERS = "loggers";
060    private static final String SCRIPTS = "scripts";
061    private static final String FILTERS = "filters";
062    private static final String STATUS = "status";
063    private static final String NAME = "name";
064    private static final String REF = "ref";
065
066    /**
067     * Merge the root properties.
068     * @param rootNode The composite root node.
069     * @param configuration The configuration to merge.
070     */
071    @Override
072    public void mergeRootProperties(final Node rootNode, final AbstractConfiguration configuration) {
073        for (final Map.Entry<String, String> attribute : configuration.getRootNode().getAttributes().entrySet()) {
074            boolean isFound = false;
075            for (final Map.Entry<String, String> targetAttribute : rootNode.getAttributes().entrySet()) {
076                if (targetAttribute.getKey().equalsIgnoreCase(attribute.getKey())) {
077                    if (attribute.getKey().equalsIgnoreCase(STATUS)) {
078                        final Level targetLevel = Level.getLevel(targetAttribute.getValue().toUpperCase());
079                        final Level sourceLevel = Level.getLevel(attribute.getValue().toUpperCase());
080                        if (targetLevel != null && sourceLevel != null) {
081                            if (sourceLevel.isLessSpecificThan(targetLevel)) {
082                                targetAttribute.setValue(attribute.getValue());
083                            }
084                        } else
085                            if (sourceLevel != null) {
086                                targetAttribute.setValue(attribute.getValue());
087                            }
088                    } else {
089                        if (attribute.getKey().equalsIgnoreCase("monitorInterval")) {
090                            final int sourceInterval = Integer.parseInt(attribute.getValue());
091                            final int targetInterval = Integer.parseInt(targetAttribute.getValue());
092                            if (targetInterval == 0 || sourceInterval < targetInterval) {
093                                targetAttribute.setValue(attribute.getValue());
094                            }
095                        } else {
096                            targetAttribute.setValue(attribute.getValue());
097                        }
098                    }
099                    isFound = true;
100                }
101            }
102            if (!isFound) {
103                rootNode.getAttributes().put(attribute.getKey(), attribute.getValue());
104            }
105        }
106    }
107
108    /**
109     * Merge the source Configuration into the target Configuration.
110     *
111     * @param target        The target node to merge into.
112     * @param source        The source node.
113     * @param pluginManager The PluginManager.
114     */
115    @Override
116    public void mergConfigurations(final Node target, final Node source, final PluginManager pluginManager) {
117        for (final Node sourceChildNode : source.getChildren()) {
118            final boolean isFilter = isFilterNode(sourceChildNode);
119            boolean isMerged = false;
120            for (final Node targetChildNode : target.getChildren()) {
121                if (isFilter) {
122                    if (isFilterNode(targetChildNode)) {
123                        updateFilterNode(target, targetChildNode, sourceChildNode, pluginManager);
124                        isMerged = true;
125                        break;
126                    }
127                    continue;
128                }
129
130                if (!targetChildNode.getName().equalsIgnoreCase(sourceChildNode.getName())) {
131                    continue;
132                }
133
134                switch (targetChildNode.getName().toLowerCase()) {
135                    case PROPERTIES:
136                    case SCRIPTS:
137                    case APPENDERS: {
138                        for (final Node node : sourceChildNode.getChildren()) {
139                            for (final Node targetNode : targetChildNode.getChildren()) {
140                                if (Objects.equals(targetNode.getAttributes().get(NAME), node.getAttributes().get(NAME))) {
141                                    targetChildNode.getChildren().remove(targetNode);
142                                    break;
143                                }
144                            }
145                            targetChildNode.getChildren().add(node);
146                        }
147                        isMerged = true;
148                        break;
149                    }
150                    case LOGGERS: {
151                        final Map<String, Node> targetLoggers = new HashMap<>();
152                        for (final Node node : targetChildNode.getChildren()) {
153                            targetLoggers.put(node.getName(), node);
154                        }
155                        for (final Node node : sourceChildNode.getChildren()) {
156                            final Node targetNode = getLoggerNode(targetChildNode, node.getAttributes().get(NAME));
157                            final Node loggerNode = new Node(targetChildNode, node.getName(), node.getType());
158                            if (targetNode != null) {
159                                targetNode.getAttributes().putAll(node.getAttributes());
160                                for (final Node sourceLoggerChild : node.getChildren()) {
161                                    if (isFilterNode(sourceLoggerChild)) {
162                                        boolean foundFilter = false;
163                                        for (final Node targetChild : targetNode.getChildren()) {
164                                            if (isFilterNode(targetChild)) {
165                                                updateFilterNode(loggerNode, targetChild, sourceLoggerChild,
166                                                        pluginManager);
167                                                foundFilter = true;
168                                                break;
169                                            }
170                                        }
171                                        if (!foundFilter) {
172                                            final Node childNode = new Node(loggerNode, sourceLoggerChild.getName(),
173                                                    sourceLoggerChild.getType());
174                                            targetNode.getChildren().add(childNode);
175                                        }
176                                    } else {
177                                        final Node childNode = new Node(loggerNode, sourceLoggerChild.getName(),
178                                                sourceLoggerChild.getType());
179                                        childNode.getAttributes().putAll(sourceLoggerChild.getAttributes());
180                                        childNode.getChildren().addAll(sourceLoggerChild.getChildren());
181                                        if (childNode.getName().equalsIgnoreCase("AppenderRef")) {
182                                            for (final Node targetChild : targetNode.getChildren()) {
183                                                if (isSameReference(targetChild, childNode)) {
184                                                    targetNode.getChildren().remove(targetChild);
185                                                    break;
186                                                }
187                                            }
188                                        } else {
189                                            for (final Node targetChild : targetNode.getChildren()) {
190                                                if (isSameName(targetChild, childNode)) {
191                                                    targetNode.getChildren().remove(targetChild);
192                                                    break;
193                                                }
194                                            }
195                                        }
196
197                                        targetNode.getChildren().add(childNode);
198                                    }
199                                }
200                            } else {
201                                loggerNode.getAttributes().putAll(node.getAttributes());
202                                loggerNode.getChildren().addAll(node.getChildren());
203                                targetChildNode.getChildren().add(loggerNode);
204                            }
205                        }
206                        isMerged = true;
207                        break;
208                    }
209                    default: {
210                        targetChildNode.getChildren().addAll(sourceChildNode.getChildren());
211                        isMerged = true;
212                        break;
213                    }
214
215                }
216            }
217            if (!isMerged) {
218                if (sourceChildNode.getName().equalsIgnoreCase("Properties")) {
219                    target.getChildren().add(0, sourceChildNode);
220                } else {
221                    target.getChildren().add(sourceChildNode);
222                }
223            }
224        }
225    }
226
227    private Node getLoggerNode(final Node parentNode, final String name) {
228        for (final Node node : parentNode.getChildren()) {
229            final String nodeName = node.getAttributes().get(NAME);
230            if (name == null && nodeName == null) {
231                return node;
232            }
233            if (nodeName != null && nodeName.equals(name)) {
234                return node;
235            }
236        }
237        return null;
238    }
239
240    private void updateFilterNode(final Node target, final Node targetChildNode, final Node sourceChildNode,
241            final PluginManager pluginManager) {
242        if (CompositeFilter.class.isAssignableFrom(targetChildNode.getType().getPluginClass())) {
243            final Node node = new Node(targetChildNode, sourceChildNode.getName(), sourceChildNode.getType());
244            node.getChildren().addAll(sourceChildNode.getChildren());
245            node.getAttributes().putAll(sourceChildNode.getAttributes());
246            targetChildNode.getChildren().add(node);
247        } else {
248            final PluginType pluginType = pluginManager.getPluginType(FILTERS);
249            final Node filtersNode = new Node(targetChildNode, FILTERS, pluginType);
250            final Node node = new Node(filtersNode, sourceChildNode.getName(), sourceChildNode.getType());
251            node.getAttributes().putAll(sourceChildNode.getAttributes());
252            final List<Node> children = filtersNode.getChildren();
253            children.add(targetChildNode);
254            children.add(node);
255            final List<Node> nodes = target.getChildren();
256            nodes.remove(targetChildNode);
257            nodes.add(filtersNode);
258        }
259    }
260
261    private boolean isFilterNode(final Node node) {
262        return Filter.class.isAssignableFrom(node.getType().getPluginClass());
263    }
264
265    private boolean isSameName(final Node node1, final Node node2) {
266        final String value = node1.getAttributes().get(NAME);
267        return value != null && value.toLowerCase().equals(node2.getAttributes().get(NAME).toLowerCase());
268    }
269
270    private boolean isSameReference(final Node node1, final Node node2) {
271        final String value = node1.getAttributes().get(REF);
272        return value != null && value.toLowerCase().equals(node2.getAttributes().get(REF).toLowerCase());
273    }
274}