001/*
002 * (C) Copyright 2013 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Thomas Roger
018 */
019
020package org.nuxeo.ecm.core.api.impl;
021
022import java.util.Collections;
023import java.util.HashSet;
024import java.util.List;
025import java.util.Set;
026
027import org.apache.commons.logging.Log;
028import org.apache.commons.logging.LogFactory;
029import org.nuxeo.ecm.core.api.CoreSession;
030import org.nuxeo.ecm.core.api.DocumentModel;
031import org.nuxeo.ecm.core.api.Filter;
032
033/**
034 * A filter based on permissions.
035 * <p>
036 * If one of the permission check throws an Exception, the {@link #accept} method returns false.
037 *
038 * @since 5.7.2
039 */
040public class PermissionFilter implements Filter {
041
042    private static final long serialVersionUID = 1L;
043
044    private static final Log log = LogFactory.getLog(PermissionFilter.class);
045
046    protected final Set<String> required;
047
048    protected final Set<String> excluded;
049
050    public PermissionFilter(List<String> required, List<String> excluded) {
051        if (required == null) {
052            this.required = Collections.emptySet();
053        } else {
054            this.required = new HashSet<>(required);
055        }
056        if (excluded == null) {
057            this.excluded = Collections.emptySet();
058        } else {
059            this.excluded = new HashSet<>(excluded);
060        }
061    }
062
063    public PermissionFilter(String permission, boolean isRequired) {
064        if (isRequired) {
065            required = Collections.singleton(permission);
066            excluded = Collections.emptySet();
067        } else {
068            required = Collections.emptySet();
069            excluded = Collections.singleton(permission);
070        }
071    }
072
073    @Override
074    public boolean accept(DocumentModel docModel) {
075        CoreSession session = docModel.getCoreSession();
076        return session != null && hasPermission(session, docModel, excluded, false)
077                && hasPermission(session, docModel, required, true);
078
079    }
080
081    protected boolean hasPermission(CoreSession session, DocumentModel doc, Set<String> permissions, boolean required) {
082        for (String permission : permissions) {
083            if ((required && !session.hasPermission(doc.getRef(), permission))
084                    || (!required && session.hasPermission(doc.getRef(), permission))) {
085                return false;
086            }
087        }
088        return true;
089    }
090
091}