/*
* 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.solr.search.join;
import org.apache.lucene.search.Query;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.request.SolrQueryRequest;
import org.apache.solr.search.QParser;
import org.apache.solr.search.QueryParsing;
import org.apache.solr.search.SyntaxError;
/**
* Solr query parser that will handle parsing graph query requests.
*/
public class GraphQueryParser extends QParser {
public GraphQueryParser(String qstr, SolrParams localParams, SolrParams params, SolrQueryRequest req) {
super(qstr, localParams, params, req);
}
@Override
public Query parse() throws SyntaxError {
// grab query params and defaults
SolrParams localParams = getLocalParams();
Query rootNodeQuery = subQuery(localParams.get(QueryParsing.V), null).getQuery();
String traversalFilterS = localParams.get("traversalFilter");
Query traversalFilter = traversalFilterS == null ? null : subQuery(traversalFilterS, null).getQuery();
String fromField = localParams.get("from", "node_id");
String toField = localParams.get("to", "edge_ids");
// only documents that do not have values in the edge id fields.
boolean onlyLeafNodes = localParams.getBool("returnOnlyLeaf", false);
// choose if you want to return documents that match the initial query or not.
boolean returnRootNodes = localParams.getBool("returnRoot", true);
// enable or disable the use of an automaton term for the frontier traversal.
int maxDepth = localParams.getInt("maxDepth", -1);
// if true, an automaton will be compiled to issue the next graph hop
// this avoid having a large number of boolean clauses. (and it's faster too!)
boolean useAutn = localParams.getBool("useAutn", false);
// Construct a graph query object based on parameters passed in.
GraphQuery gq = new GraphQuery(rootNodeQuery, fromField, toField, traversalFilter);
// set additional parameters that are not in the constructor.
gq.setMaxDepth(maxDepth);
gq.setOnlyLeafNodes(onlyLeafNodes);
gq.setReturnRoot(returnRootNodes);
gq.setUseAutn(useAutn);
// return the parsed graph query.
return gq;
}
}