001/*
002 * Logback: the reliable, generic, fast and flexible logging framework.
003 * Copyright (C) 1999-2026, QOS.ch. All rights reserved.
004 *
005 * This program and the accompanying materials are dual-licensed under
006 * either the terms of the Eclipse Public License v2.0 as published by
007 * the Eclipse Foundation
008 *
009 *   or (per the licensee's choosing)
010 *
011 * under the terms of the GNU Lesser General Public License version 2.1
012 * as published by the Free Software Foundation.
013 */
014
015package ch.qos.logback.core.model.processor;
016
017import ch.qos.logback.core.Context;
018import ch.qos.logback.core.FileAppender;
019import ch.qos.logback.core.model.AppenderModel;
020import ch.qos.logback.core.model.ImplicitModel;
021import ch.qos.logback.core.model.Model;
022import ch.qos.logback.core.rolling.RollingFileAppender;
023import ch.qos.logback.core.rolling.helper.FileNamePattern;
024
025import java.util.HashMap;
026import java.util.List;
027import java.util.Map;
028import java.util.Optional;
029import java.util.function.Supplier;
030import java.util.stream.Collectors;
031import java.util.stream.Stream;
032
033@PhaseIndicator(phase = ProcessingPhase.DEPENDENCY_ANALYSIS)
034public class FileCollisionAnalyser extends ModelHandlerBase {
035
036    public FileCollisionAnalyser(Context context) {
037        super(context);
038    }
039
040    @Override
041    protected Class<AppenderModel> getSupportedModelClass() {
042        return AppenderModel.class;
043    }
044
045
046    @Override
047    public void handle(ModelInterpretationContext mic, Model model) throws ModelHandlerException {
048        AppenderModel appenderModel = (AppenderModel) model;
049
050        String originalClassName = appenderModel.getClassName();
051        String className = mic.getImport(originalClassName);
052
053        String appenderName = appenderModel.getName();
054
055        if (!fileAppenderOrRollingFileAppender(className)) {
056            return;
057        }
058
059        String tagName0 = "file";
060        checkForCollisions(mic, MapKey.FILE_COLLISION_MAP_KEY, appenderModel, appenderName, tagName0);
061
062        String tagName1 = "fileNamePattern";
063        checkForCollisions(mic, MapKey.RFA_FILENAME_COLLISION_MAP, appenderModel, appenderName, tagName1);
064    }
065
066    private static boolean fileAppenderOrRollingFileAppender(String className) {
067        return FileAppender.class.getName().equals(className) || RollingFileAppender.class.getName().equals(className);
068    }
069
070
071    boolean tagPredicate(Model model, String tagName) {
072        return (model instanceof ImplicitModel) && tagName.equals(model.getTag());
073    }
074
075    enum MapKey {
076        FILE_COLLISION_MAP_KEY, RFA_FILENAME_COLLISION_MAP
077    }
078
079    private void checkForCollisions(ModelInterpretationContext mic, MapKey mapKey, AppenderModel appenderModel, String appenderName, final String tagName) {
080
081
082        Stream<Model> streamLevel1 = appenderModel.getSubModels().stream();
083        Stream<Model> streamLevel2 = appenderModel.getSubModels().stream().flatMap(child -> child.getSubModels().stream());
084
085        List<Model> matchingModels = Stream.concat(streamLevel1, streamLevel2).filter(m -> tagPredicate(m, tagName)).collect(Collectors.toList());
086
087        if(!matchingModels.isEmpty()) {
088            ImplicitModel implicitModel = (ImplicitModel) matchingModels.get(0);
089            String bodyValue = mic.subst(implicitModel.getBodyText());
090
091
092            Map<String, String> collisionMap = getCollisionMapByKey(mic, mapKey);
093
094            Optional<Map.Entry<String, String>> collision = collisionMap.entrySet()
095                    .stream()
096                    .filter(entry -> bodyValue.equals(entry.getValue()))
097                    .findFirst();
098
099            if (collision.isPresent()) {
100                addErrorForCollision(tagName, appenderName, collision.get().getKey(), bodyValue);
101                appenderModel.markAsHandled();
102                appenderModel.deepMarkAsSkipped();
103            } else {
104                // add to collision map if and only if no collision detected
105                // reasoning: single entry is as effective as multiple entries for collision detection
106                collisionMap.put(appenderName, bodyValue);
107            }
108        }
109    }
110
111    private Map<String, String> getCollisionMapByKey(ModelInterpretationContext mic, MapKey mapKey) {
112        Map<String, String> map = (Map<String, String>) mic.getObjectMap().get(mapKey.name());
113        if(map == null) {
114            map = new HashMap<>();
115            mic.getObjectMap().put(mapKey.name(), map);
116        }
117        return map;
118    }
119
120
121    static public final String COLLISION_DETECTED = "Collision detected. Skipping initialization of appender named [%s]";
122    static public final String COLLISION_MESSAGE = "In appender [%s] option '%s' has the same value '%s' as that set for appender [%s] defined earlier";
123    private void addErrorForCollision(String optionName, String appenderName, String previousAppenderName, String optionValue) {
124        addError(String.format(COLLISION_DETECTED, appenderName));
125        addError(String.format(COLLISION_MESSAGE, appenderName, optionName, optionValue, previousAppenderName));
126    }
127}