/// <summary>
/// Filter out any points outside of the queried area from the input list.
/// </summary>
/// <param name="list">List of items return by Amazon DynamoDB. It may contains points outside of the actual area queried.</param>
/// <param name="geoQueryRequest">List of items within the queried area.</param>
/// <returns></returns>
private IEnumerable <IDictionary <string, AttributeValue> > Filter(IEnumerable <IDictionary <string, AttributeValue> > list,
GeoQueryRequest geoQueryRequest)
{
var result = new List <IDictionary <String, AttributeValue> >();
S2LatLngRect?latLngRect = null;
S2LatLng? centerLatLng = null;
double radiusInMeter = 0;
if (geoQueryRequest is QueryRectangleRequest)
{
latLngRect = S2Util.GetBoundingLatLngRect(geoQueryRequest);
}
foreach (var item in list)
{
var geoJson = item[_config.GeoJsonAttributeName].S;
var geoPoint = GeoJsonMapper.GeoPointFromString(geoJson);
var latLng = S2LatLng.FromDegrees(geoPoint.lat, geoPoint.lng);
if (latLngRect != null && latLngRect.Value.Contains(latLng))
{
result.Add(item);
}
else if (centerLatLng != null && radiusInMeter > 0 &&
centerLatLng.Value.GetEarthDistance(latLng) <= radiusInMeter)
{
result.Add(item);
}
}
return(result);
}
public async Task <QueryRectangleResult> QueryRectangleAsync(QueryRectangleRequest queryRectangleRequest, CancellationToken cancellationToken = default(CancellationToken))
{
if (queryRectangleRequest == null)
{
throw new ArgumentNullException("queryRectangleRequest");
}
var latLngRect = S2Util.GetBoundingLatLngRect(queryRectangleRequest);
var cellUnion = S2Manager.FindCellIds(latLngRect);
var ranges = MergeCells(cellUnion);
var result = await DispatchQueries(ranges, queryRectangleRequest, cancellationToken).ConfigureAwait(false);
return(new QueryRectangleResult(result));
}
/// <summary>
/// <p>
/// Query a circular area constructed by a center point and its radius.
/// </p>
/// <b>Sample usage:</b>
/// <pre>
/// GeoPoint centerPoint = new GeoPoint(47.5, -122.3);
/// QueryRadiusRequest queryRadiusRequest = new QueryRadiusRequest(centerPoint, 100);
/// QueryRadiusResult queryRadiusResult = geoIndexManager.queryRadius(queryRadiusRequest);
/// for (Map<String, AttributeValue> item : queryRadiusResult.getItem()) {
/// System.out.println("item: " + item);
/// }
/// </pre>
/// </summary>
/// <param name="queryRadiusRequest">Container for the necessary parameters to execute radius query request.</param>
/// <returns>Result of radius query request.</returns>
public async Task <QueryRadiusResult> QueryRadiusAsync(QueryRadiusRequest queryRadiusRequest, CancellationToken cancellationToken = default(CancellationToken))
{
if (queryRadiusRequest == null)
{
throw new ArgumentNullException("queryRadiusRequest");
}
if (queryRadiusRequest.RadiusInMeter <= 0 || queryRadiusRequest.RadiusInMeter > S2LatLng.EarthRadiusMeters)
{
throw new ArgumentOutOfRangeException("queryRadiusRequest", "RadiusInMeter needs to be > 0 and <= " + S2LatLng.EarthRadiusMeters);
}
var latLngRect = S2Util.GetBoundingLatLngRect(queryRadiusRequest);
var cellUnion = S2Manager.FindCellIds(latLngRect);
var ranges = MergeCells(cellUnion);
var result = await DispatchQueries(ranges, queryRadiusRequest, cancellationToken).ConfigureAwait(false);
return(new QueryRadiusResult(result));
}
