001/*
002 * (C) Copyright 2017 Nuxeo (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 *     Florent Guillaume
018 */
019package org.nuxeo.ecm.core.storage.dbs;
020
021import static org.nuxeo.ecm.core.storage.dbs.DBSDocument.KEY_ACL;
022import static org.nuxeo.ecm.core.storage.dbs.DBSDocument.KEY_ACP;
023
024import java.util.regex.Matcher;
025import java.util.regex.Pattern;
026
027import org.nuxeo.ecm.core.query.sql.NXQL;
028import org.nuxeo.ecm.core.storage.QueryOptimizer;
029
030/**
031 * DBS-specific query optimizer.
032 * <p>
033 * Knows how reference prefixes are computed, especially for the ACL case which has a storage structure different than
034 * what the NXQL syntax suggests.
035 *
036 * @since 9.3
037 */
038public class DBSQueryOptimizer extends QueryOptimizer {
039
040    protected static final Pattern CORRELATED_WILDCARD_SPLIT = Pattern.compile("(([^*]+)/(\\*\\d+))/(.*)");
041
042    protected static final Pattern CORRELATED_ECM_TAG = Pattern.compile(NXQL.ECM_TAG + "/\\*\\d+");
043
044    protected static final String CORRELATED_ECM_TAG_IMPLICIT = "__ecm_tag_correlated__";
045
046    @Override
047    public String getCorrelatedWildcardPrefix(String name) {
048        if (name.startsWith(NXQL.ECM_TAG)) {
049            if (name.equals(NXQL.ECM_TAG)) {
050                // naked ecm:tag are always correlated with themselves
051                return CORRELATED_ECM_TAG_IMPLICIT;
052            } else if (CORRELATED_ECM_TAG.matcher(name).matches()) {
053                return name;
054            } else {
055                return "";
056            }
057        }
058        Matcher m = CORRELATED_WILDCARD_SPLIT.matcher(name);
059        if (!m.matches()) {
060            return "";
061        }
062        String start = m.group(2);
063        String wildcard = m.group(3);
064        String end = m.group(4);
065        if (start.equals(NXQL.ECM_ACL)) {
066            if (end.equals(NXQL.ECM_ACL_NAME)) {
067                return KEY_ACP + '/' + wildcard;
068            } else {
069                return KEY_ACP + '/' + wildcard + '/' + KEY_ACL + '/' + wildcard;
070            }
071        } else {
072            return m.group(1);
073        }
074    }
075
076}