public Task <Result <FindNearestRouteNodesResult> > HandleAsync(FindNearestRouteNodes query)
{
Stopwatch sw = new();
sw.Start();
var getRouteNetworkElementsResult = _routeNodeRepository.GetRouteElements(new RouteNetworkElementIdList()
{
query.SourceRouteNodeId
});
// Here we return a error result, because we're dealing with invalid route network ids provided by the client
if (getRouteNetworkElementsResult.IsFailed || getRouteNetworkElementsResult.Value.Count != 1)
{
return(Task.FromResult(
Result.Fail <FindNearestRouteNodesResult>(new FindNearestRouteNodesError(FindNearestRouteNodesErrorCodes.INVALID_QUERY_ARGUMENT_ERROR_LOOKING_UP_SPECIFIED_ROUTE_NETWORK_ELEMENT_BY_ID, $"Error looking up route network node with id: {query.SourceRouteNodeId}")).
WithError(getRouteNetworkElementsResult.Errors.First())
));
}
var sourceRouteNode = getRouteNetworkElementsResult.Value.First() as RouteNode;
if (sourceRouteNode == null)
{
return(Task.FromResult(
Result.Fail <FindNearestRouteNodesResult>(new FindNearestRouteNodesError(FindNearestRouteNodesErrorCodes.INVALID_QUERY_ARGUMENT_ERROR_LOOKING_UP_SPECIFIED_ROUTE_NETWORK_ELEMENT_BY_ID, $"Error looking up route network node. Got { getRouteNetworkElementsResult.Value.First().GetType().Name} querying element with id: {query.SourceRouteNodeId}")).
WithError(getRouteNetworkElementsResult.Errors.First())
));
}
var sourceRouteNodePoint = GetPoint(sourceRouteNode.Coordinates);
long version = _routeNetworkState.GetLatestCommitedVersion();
var stopHash = query.NodeKindStops.ToHashSet();
var interestHash = query.NodeKindOfInterests.ToHashSet();
// Fetch objects from route network graph to query on
var routeNetworkSubset = sourceRouteNode.UndirectionalDFS <RouteNode, RouteSegment>(
version: version,
nodeCriteria: n => (n.RouteNodeInfo == null || n.RouteNodeInfo.Kind == null || !stopHash.Contains(n.RouteNodeInfo.Kind.Value)) && GetPoint(n.Coordinates).Distance(sourceRouteNodePoint) < query.SearchRadiusMeters,
includeElementsWhereCriteriaIsFalse: true
);
// Find nodes to check/trace shortest path
var nodeCandidates = GetAllNodeCandidates(sourceRouteNode, interestHash, routeNetworkSubset);
var graphForTracing = GetGraphForTracing(version, nodeCandidates, routeNetworkSubset);
var nodesOfInterest = GetNodesOfInterest(nodeCandidates, interestHash).ToList();
ConcurrentBag <NearestRouteNodeTraceResult> nodeTraceResults = new();
int nShortestPathTraces = 0;
ParallelOptions po = new ParallelOptions();
po.MaxDegreeOfParallelism = Environment.ProcessorCount;
foreach (var nodeToTrace in nodesOfInterest)
{
var shortestPathTrace = ShortestPath(nodeToTrace.Node, sourceRouteNode.Id, graphForTracing);
nodeTraceResults.Add(shortestPathTrace);
nShortestPathTraces++;
if (NumberOfShortestPathTracesWithinDistance(nodeTraceResults, nodeToTrace.BirdDistanceToSource) >= query.MaxHits)
{
break;
}
}
var nodeTraceResultOrdered = nodeTraceResults.OrderBy(n => n.Distance).ToList();
sw.Stop();
_logger.LogInformation($"{nShortestPathTraces} shortets path trace(s) processed in {sw.ElapsedMilliseconds} milliseconds finding the {query.MaxHits} nearest nodes to source node with id: {sourceRouteNode.Id}");
List <NearestRouteNodeTraceResult> tracesToReturn = new();
List <IRouteNetworkElement> routeNodeElementsToReturn = new();
for (int i = 0; i < query.MaxHits && i < nodeTraceResultOrdered.Count; i++)
{
// Add trace
var traceToAdd = nodeTraceResultOrdered[i];
tracesToReturn.Add(traceToAdd);
var routeElementToAdd = _routeNodeRepository.NetworkState.GetRouteNetworkElement(traceToAdd.DestNodeId);
if (routeElementToAdd != null)
{
routeNodeElementsToReturn.Add(routeElementToAdd);
}
}
var result = new FindNearestRouteNodesResult(
sourceRouteNodeId: sourceRouteNode.Id,
routeNetworkElements: GetRouteNetworkDetailsQueryHandler.MapRouteElementDomainObjectsToQueryObjects(query.RouteNetworkElementFilter, routeNodeElementsToReturn),
routeNetworkTraces: tracesToReturn
);
return(Task.FromResult(
Result.Ok <FindNearestRouteNodesResult>(
result
)
));
}