/**
* 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.schema;
import org.apache.lucene.document.Fieldable;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.SortField;
import org.apache.lucene.spatial.DistanceUtils;
import org.apache.lucene.spatial.geohash.GeoHashUtils;
import org.apache.lucene.spatial.tier.InvalidGeoException;
import org.apache.solr.common.SolrException;
import org.apache.solr.response.TextResponseWriter;
import org.apache.solr.response.XMLWriter;
import org.apache.solr.search.QParser;
import org.apache.solr.search.SolrConstantScoreQuery;
import org.apache.solr.search.SpatialOptions;
import org.apache.solr.search.function.LiteralValueSource;
import org.apache.solr.search.function.ValueSource;
import org.apache.solr.search.function.ValueSourceRangeFilter;
import org.apache.solr.search.function.distance.GeohashHaversineFunction;
import java.io.IOException;
/**
* This is a class that represents a <a
* href="http://en.wikipedia.org/wiki/Geohash">Geohash</a> field. The field is
* provided as a lat/lon pair and is internally represented as a string.
*
* @see org.apache.lucene.spatial.DistanceUtils#parseLatitudeLongitude(double[], String)
*/
public class GeoHashField extends FieldType implements SpatialQueryable {
@Override
public SortField getSortField(SchemaField field, boolean top) {
return getStringSort(field, top);
}
//QUESTION: Should we do a fast and crude one? Or actually check distances
//Fast and crude could use EdgeNGrams, but that would require a different
//encoding. Plus there are issues around the Equator/Prime Meridian
public Query createSpatialQuery(QParser parser, SpatialOptions options) {
double [] point = new double[0];
try {
point = DistanceUtils.parsePointDouble(null, options.pointStr, 2);
} catch (InvalidGeoException e) {
throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e);
}
String geohash = GeoHashUtils.encode(point[0], point[1]);
//TODO: optimize this
return new SolrConstantScoreQuery(new ValueSourceRangeFilter(new GeohashHaversineFunction(getValueSource(options.field, parser),
new LiteralValueSource(geohash), options.radius), "0", String.valueOf(options.distance), true, true));
}
@Override
public void write(XMLWriter xmlWriter, String name, Fieldable f)
throws IOException {
xmlWriter.writeStr(name, toExternal(f));
}
@Override
public void write(TextResponseWriter writer, String name, Fieldable f)
throws IOException {
writer.writeStr(name, toExternal(f), false);
}
@Override
public String toExternal(Fieldable f) {
double[] latLon = GeoHashUtils.decode(f.stringValue());
return latLon[0] + "," + latLon[1];
}
@Override
public String toInternal(String val) {
// validate that the string is of the form
// latitude, longitude
double[] latLon = new double[0];
try {
latLon = DistanceUtils.parseLatitudeLongitude(null, val);
} catch (InvalidGeoException e) {
throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, e);
}
return GeoHashUtils.encode(latLon[0], latLon[1]);
}
@Override
public ValueSource getValueSource(SchemaField field, QParser parser) {
field.checkFieldCacheSource(parser);
return new StrFieldSource(field.name);
}
}