| /* |
| * 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.jackrabbit.oak.plugins.observation.filter; |
| |
| import static com.google.common.base.Objects.toStringHelper; |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static org.apache.jackrabbit.oak.commons.PathUtils.elements; |
| |
| import java.util.ArrayList; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.regex.Pattern; |
| |
| import com.google.common.base.Joiner; |
| import com.google.common.collect.Iterators; |
| |
| import org.apache.jackrabbit.oak.api.PropertyState; |
| import org.apache.jackrabbit.oak.spi.state.NodeState; |
| import org.jetbrains.annotations.NotNull; |
| |
| /** |
| * This {@code Filter} implementation supports filtering on paths using |
| * simple glob patterns. Such a pattern is a string denoting a path. Each |
| * element of the pattern is matched against the corresponding element of |
| * a path. Elements of the pattern are matched literally except for the special |
| * elements {@code *} and {@code **} where the former matches an arbitrary |
| * path element and the latter matches any number of path elements (including none). |
| * <p> |
| * Note: an empty path pattern matches no path. |
| * <p> |
| * Note: path patterns only match against the corresponding elements of the path |
| * and <em>do not</em> distinguish between absolute and relative paths. |
| * <p> |
| * Note: there is no way to escape {@code *} and {@code **}. |
| * <p> |
| * Examples: |
| * <pre> |
| * q matches q only |
| * * matches character matches zero or more characters of a name component without crossing path boundaries (ie without crossing /) |
| * ** matches every path |
| * a/b/c matches a/b/c only |
| * a/*/c matches a/x/c for every element x |
| * a/*.html/c matches a/x.html/c for every character sequence x (that doesn't include /) |
| * a/*.*/c matches a/x.y/c for every character sequence x and y (that don't include /) |
| * **/y/z match every path ending in y/z |
| * r/s/t/** matches r/s/t and all its descendants |
| * </pre> |
| */ |
| public class GlobbingPathFilter implements EventFilter { |
| public static final String STAR = "*"; |
| public static final String STAR_STAR = "**"; |
| |
| // OAK-5589 : pattern can be a normal List, it doesn't have to be immutable - |
| // given we create a new list in the public constructor anyway |
| private final List<String> pattern; |
| private final Map<String, Pattern> patternMap; |
| |
| private GlobbingPathFilter(@NotNull List<String> pattern, Map<String, Pattern> patternMap) { |
| // OAK-5589 : for internal constructor case don't copy the pattern, refer to the same one |
| // this will work fine given the public constructors make a copy and internally we're |
| // never fiddling with the pattern list |
| this.pattern = checkNotNull(pattern); |
| this.patternMap = checkNotNull(patternMap); |
| } |
| |
| public GlobbingPathFilter(@NotNull String pattern, Map<String, Pattern> patternMap) { |
| // OAK-5589 : use the fastest way to create a List based on an unknown deep pattern |
| this.pattern = new ArrayList<String>(10); |
| Iterators.addAll(this.pattern, elements(checkNotNull(pattern)).iterator()); |
| this.patternMap = checkNotNull(patternMap); |
| } |
| |
| /** for testing only - use variant which passes the patternMap for productive code **/ |
| public GlobbingPathFilter(@NotNull String pattern) { |
| this(pattern, new HashMap<String, Pattern>()); |
| } |
| |
| @Override |
| public boolean includeAdd(PropertyState after) { |
| return includeItem(after.getName()); |
| } |
| |
| @Override |
| public boolean includeChange(PropertyState before, PropertyState after) { |
| return includeItem(after.getName()); |
| } |
| |
| @Override |
| public boolean includeDelete(PropertyState before) { |
| return includeItem(before.getName()); |
| } |
| |
| @Override |
| public boolean includeAdd(String name, NodeState after) { |
| return includeItem(name); |
| } |
| |
| @Override |
| public boolean includeDelete(String name, NodeState before) { |
| return includeItem(name); |
| } |
| |
| @Override |
| public boolean includeMove(String sourcePath, String name, NodeState moved) { |
| return includeItem(name); |
| } |
| |
| @Override |
| public boolean includeReorder(String destName, String name, NodeState reordered) { |
| return includeItem(name); |
| } |
| |
| private Pattern getPattern(String wildcardStr) { |
| Pattern p = patternMap.get(wildcardStr); |
| if (p == null) { |
| p = Pattern.compile("\\Q"+wildcardStr.replace("*", "\\E[^/]*\\Q") + "\\E"); |
| patternMap.put(wildcardStr, p); |
| } |
| return p; |
| } |
| |
| private boolean wildcardMatch(String pathElement, String wildcardStr) { |
| if (STAR_STAR.equals(wildcardStr) || !wildcardStr.contains(STAR)) { |
| return pathElement.equals(wildcardStr); |
| } |
| Pattern regexPattern = getPattern(wildcardStr); |
| return regexPattern.matcher(pathElement).matches(); |
| } |
| |
| @Override |
| public EventFilter create(String name, NodeState before, NodeState after) { |
| if (pattern.isEmpty()) { |
| return null; |
| } |
| |
| String head = pattern.get(0); |
| if (pattern.size() == 1 && !STAR_STAR.equals(head)) { |
| // shortcut when no further matches are possible |
| return null; |
| } |
| |
| if (wildcardMatch(name, head)) { |
| return new GlobbingPathFilter(pattern.subList(1, pattern.size()), patternMap); |
| } else if (STAR_STAR.equals(head)) { |
| if (pattern.size() >= 2 && wildcardMatch(name, pattern.get(1))) { |
| // ** matches empty list of elements and pattern.get(1) matches name |
| // match the rest of the pattern against the rest of the path and |
| // match the whole pattern against the rest of the path |
| return Filters.any( |
| new GlobbingPathFilter(pattern.subList(2, pattern.size()), patternMap), |
| new GlobbingPathFilter(pattern, patternMap) |
| ); |
| } else { |
| // ** matches name, match the whole pattern against the rest of the path |
| return new GlobbingPathFilter(pattern, patternMap); |
| } |
| } else { |
| return null; |
| } |
| } |
| |
| @Override |
| public String toString() { |
| return toStringHelper(this) |
| .add("path", Joiner.on('/').join(pattern)) |
| .toString(); |
| } |
| |
| //------------------------------------------------------------< private >--- |
| |
| private boolean includeItem(String name) { |
| if (!pattern.isEmpty() && pattern.size() <= 2) { |
| String head = pattern.get(0); |
| if (STAR_STAR.equals(head)) { |
| if (pattern.size() == 1) { |
| return true; |
| } else { |
| return wildcardMatch(name, pattern.get(1)); |
| } |
| } |
| boolean headMatches = wildcardMatch(name, head); |
| boolean result = pattern.size() == 1 |
| ? headMatches |
| : headMatches && STAR_STAR.equals(pattern.get(1)); |
| return result; |
| } else { |
| return false; |
| } |
| } |
| |
| } |