public IList <SearchItem> SearchByLocation(string queryString, double longitude, double latitude, double searchRadiusKm, int maxHits = 10)
{
IList <SearchItem> results;
using (var searcher = new IndexSearcher(Directory, true))
using (var analyser = new StandardAnalyzer(LuceneVersion))
{
var distance = DistanceUtils.Dist2Degrees(searchRadiusKm, DistanceUtils.EARTH_MEAN_RADIUS_KM);
var searchArea = _spatialContext.MakeCircle(longitude, latitude, distance);
var fields = new[] { Name };
var parser = new MultiFieldQueryParser(LuceneVersion, fields, analyser);
parser.DefaultOperator = QueryParser.Operator.OR; // Allow multiple terms.
var query = ParseQuery(queryString, parser);
var spatialArgs = new SpatialArgs(SpatialOperation.Intersects, searchArea);
var spatialQuery = _strategy.MakeQuery(spatialArgs);
var valueSource = _strategy.MakeRecipDistanceValueSource(searchArea);
var valueSourceFilter = new ValueSourceFilter(new QueryWrapperFilter(spatialQuery), valueSource, 0, 1);
var filteredSpatial = new FilteredQuery(query, valueSourceFilter);
var spatialRankingQuery = new FunctionQuery(valueSource);
BooleanQuery bq = new BooleanQuery();
bq.Add(filteredSpatial, Occur.MUST);
bq.Add(spatialRankingQuery, Occur.MUST);
var hits = searcher.Search(bq, maxHits).ScoreDocs;
results = MapResultsToSearchItems(hits, searcher);
}
return(results);
}
public Query MakeQuery(Query existingQuery, SpatialStrategy spatialStrategy, string shapeWKT, SpatialRelation relation,
double distanceErrorPct = 0.025, SpatialUnits?unitOverride = null)
{
SpatialOperation spatialOperation;
var shape = ReadShape(shapeWKT, unitOverride);
switch (relation)
{
case SpatialRelation.Within:
spatialOperation = SpatialOperation.IsWithin;
break;
case SpatialRelation.Contains:
spatialOperation = SpatialOperation.Contains;
break;
case SpatialRelation.Disjoint:
spatialOperation = SpatialOperation.IsDisjointTo;
break;
case SpatialRelation.Intersects:
spatialOperation = SpatialOperation.Intersects;
break;
case SpatialRelation.Nearby:
// only sort by this, do not filter
return(new FunctionQuery(spatialStrategy.MakeDistanceValueSource(shape.GetCenter())));
default:
throw new ArgumentOutOfRangeException("relation");
}
var args = new SpatialArgs(spatialOperation, shape)
{
DistErrPct = distanceErrorPct
};
if (existingQuery is MatchAllDocsQuery)
{
return(new CustomScoreQuery(spatialStrategy.MakeQuery(args), new ValueSourceQuery(spatialStrategy.MakeRecipDistanceValueSource(shape))));
}
return(spatialStrategy.MakeQuery(args));
}
