public override bool Init()
{
log.Info("()");
bool res = false;
try
{
client = new LocClient(Config.Configuration.LocEndPoint, new LocMessageProcessor(), ShutdownSignaling);
this.Location = Config.Configuration.LocLocation;
locConnectionThread = new Thread(new ThreadStart(LocConnectionThread));
locConnectionThread.Start();
RegisterCronJobs();
res = true;
Initialized = true;
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
if (!res)
{
ShutdownSignaling.SignalShutdown();
if ((locConnectionThread != null) && !locConnectionThreadFinished.WaitOne(10000))
{
log.Error("LOC connection thread did not terminated in 10 seconds.");
}
}
log.Info("(-):{0}", res);
return(res);
}
/// <summary>
/// Processing of a message received from a client.
/// </summary>
/// <param name="Client">TCP client who received the message.</param>
/// <param name="IncomingMessage">Full ProtoBuf message to be processed.</param>
/// <returns>true if the conversation with the client should continue, false if a protocol violation error occurred and the client should be disconnected.</returns>
public async Task <bool> ProcessMessageAsync(ClientBase Client, IProtocolMessage IncomingMessage)
{
LocClient client = (LocClient)Client;
LocProtocolMessage incomingMessage = (LocProtocolMessage)IncomingMessage;
log.Debug("()");
bool res = false;
try
{
log.Trace("Received message type is {0}, message ID is {1}.", incomingMessage.MessageTypeCase, incomingMessage.Id);
switch (incomingMessage.MessageTypeCase)
{
case Message.MessageTypeOneofCase.Request:
{
LocProtocolMessage responseMessage = client.MessageBuilder.CreateErrorProtocolViolationResponse(incomingMessage);
Request request = incomingMessage.Request;
SemVer version = new SemVer(request.Version);
log.Trace("Request type is {0}, version is {1}.", request.RequestTypeCase, version);
switch (request.RequestTypeCase)
{
case Request.RequestTypeOneofCase.LocalService:
{
log.Trace("Local service request type is {0}.", request.LocalService.LocalServiceRequestTypeCase);
switch (request.LocalService.LocalServiceRequestTypeCase)
{
case LocalServiceRequest.LocalServiceRequestTypeOneofCase.NeighbourhoodChanged:
{
responseMessage = await ProcessMessageNeighbourhoodChangedNotificationRequestAsync(client, incomingMessage);
break;
}
default:
log.Warn("Invalid local service request type '{0}'.", request.LocalService.LocalServiceRequestTypeCase);
break;
}
break;
}
default:
log.Warn("Invalid request type '{0}'.", request.RequestTypeCase);
break;
}
if (responseMessage != null)
{
// Send response to client.
res = await client.SendMessageAsync(responseMessage);
if (res)
{
// If the message was sent successfully to the target, we close the connection only in case of protocol violation error.
if (responseMessage.MessageTypeCase == Message.MessageTypeOneofCase.Response)
{
res = responseMessage.Response.Status != Status.ErrorProtocolViolation;
}
}
}
else
{
// If there is no response to send immediately to the client,
// we want to keep the connection open.
res = true;
}
break;
}
case Message.MessageTypeOneofCase.Response:
{
Response response = incomingMessage.Response;
log.Trace("Response status is {0}, details are '{1}', response type is {2}.", response.Status, response.Details, response.ResponseTypeCase);
// The only response we should ever receive here is GetNeighbourNodesByDistanceResponse in response to our refresh request that we do from time to time.
bool isGetNeighbourNodesByDistanceResponse = (response.Status == Status.Ok) &&
(response.ResponseTypeCase == Response.ResponseTypeOneofCase.LocalService) &&
(response.LocalService.LocalServiceResponseTypeCase == LocalServiceResponse.LocalServiceResponseTypeOneofCase.GetNeighbourNodes);
if (!isGetNeighbourNodesByDistanceResponse)
{
log.Error("Unexpected response type {0} received, status code {1}.", response.ResponseTypeCase, response.Status);
break;
}
// Process the response.
res = await ProcessMessageGetNeighbourNodesByDistanceResponseAsync(incomingMessage, false);
break;
}
default:
log.Error("Unknown message type '{0}', connection to the client will be closed.", incomingMessage.MessageTypeCase);
await SendProtocolViolation(client);
// Connection will be closed in ReceiveMessageLoop.
break;
}
}
catch (Exception e)
{
log.Error("Exception occurred, connection to the client will be closed: {0}", e.ToString());
await SendProtocolViolation(client);
// Connection will be closed in ReceiveMessageLoop.
}
log.Debug("(-):{0}", res);
return(res);
}
/// <summary>
/// Processes NeighbourhoodChangedNotificationRequest message from LOC server.
/// <para>Adds, changes, or deletes neighbor and possibly adds new neighborhood action to the database.</para>
/// </summary>
/// <param name="Client">TCP client who received the message.</param>
/// <param name="RequestMessage">Full request message.</param>
/// <returns>Response message to be sent to the client.</returns>
public async Task <LocProtocolMessage> ProcessMessageNeighbourhoodChangedNotificationRequestAsync(LocClient Client, LocProtocolMessage RequestMessage)
{
log.Trace("()");
LocProtocolMessage res = Client.MessageBuilder.CreateErrorInternalResponse(RequestMessage);
bool signalActionProcessor = false;
NeighbourhoodChangedNotificationRequest neighbourhoodChangedNotificationRequest = RequestMessage.Request.LocalService.NeighbourhoodChanged;
using (UnitOfWork unitOfWork = new UnitOfWork())
{
DatabaseLock[] lockObjects = new DatabaseLock[] { UnitOfWork.NeighborLock, UnitOfWork.NeighborhoodActionLock };
using (IDbContextTransaction transaction = await unitOfWork.BeginTransactionWithLockAsync(lockObjects))
{
bool success = false;
bool saveDb = false;
try
{
int neighborhoodSize = await unitOfWork.NeighborRepository.CountAsync();
foreach (NeighbourhoodChange change in neighbourhoodChangedNotificationRequest.Changes)
{
// We do ignore errors here for each individual change and just continue processing the next item from the list.
log.Trace("Neighborhood change type is {0}.", change.ChangeTypeCase);
switch (change.ChangeTypeCase)
{
case NeighbourhoodChange.ChangeTypeOneofCase.AddedNodeInfo:
case NeighbourhoodChange.ChangeTypeOneofCase.UpdatedNodeInfo:
{
bool isAdd = change.ChangeTypeCase == NeighbourhoodChange.ChangeTypeOneofCase.AddedNodeInfo;
NodeInfo nodeInfo = isAdd ? change.AddedNodeInfo : change.UpdatedNodeInfo;
// Check whether a proximity server is running on this node.
// If not, it is not interesting for us at all, skip it.
int proximityServerPort;
byte[] proximityServerId;
if (!HasProximityServerService(nodeInfo, out proximityServerPort, out proximityServerId))
{
break;
}
NodeContact contact = nodeInfo.Contact;
IPAddress ipAddress = new IPAddress(contact.IpAddress.ToByteArray());
Iop.Locnet.GpsLocation location = nodeInfo.Location;
int latitude = location.Latitude;
int longitude = location.Longitude;
AddOrChangeNeighborResult addChangeRes = await AddOrChangeNeighborAsync(unitOfWork, proximityServerId, ipAddress, proximityServerPort, latitude, longitude, neighborhoodSize);
neighborhoodSize = addChangeRes.NeighborhoodSize;
if (addChangeRes.SaveDb)
{
saveDb = true;
}
if (addChangeRes.SignalActionProcessor)
{
signalActionProcessor = true;
}
break;
}
case NeighbourhoodChange.ChangeTypeOneofCase.RemovedNodeId:
{
byte[] serverId = change.RemovedNodeId.ToByteArray();
bool serverIdValid = serverId.Length == ProtocolHelper.NetworkIdentifierLength;
if (!serverIdValid)
{
log.Error("Received invalid neighbor server ID '{0}' from LOC server.", serverId.ToHex());
break;
}
// Data processing.
Neighbor existingNeighbor = (await unitOfWork.NeighborRepository.GetAsync(n => n.NetworkId == serverId)).FirstOrDefault();
if (existingNeighbor != null)
{
log.Trace("Creating neighborhood action to deleting neighbor ID '{0}' from the database.", serverId.ToHex());
string neighborInfo = JsonConvert.SerializeObject(existingNeighbor);
// Delete neighbor completely.
// This will cause our proximity server to erase all activities of the neighbor that has been removed.
bool deleted = await unitOfWork.NeighborRepository.DeleteNeighborAsync(serverId, -1, true);
if (deleted)
{
// Add action that will contact the neighbor and ask it to stop sending updates.
// Note that the neighbor information will be deleted by the time this action
// is executed and this is why we have to fill in AdditionalData.
NeighborhoodAction stopUpdatesAction = new NeighborhoodAction()
{
ServerId = serverId,
Timestamp = DateTime.UtcNow,
Type = NeighborhoodActionType.StopNeighborhoodUpdates,
TargetActivityId = 0,
TargetActivityOwnerId = null,
ExecuteAfter = DateTime.UtcNow,
AdditionalData = neighborInfo
};
await unitOfWork.NeighborhoodActionRepository.InsertAsync(stopUpdatesAction);
signalActionProcessor = true;
saveDb = true;
}
else
{
log.Error("Failed to remove neighbor ID '{0}' from the database.", serverId.ToHex());
// This is actually bad, we failed to remove a record from the database, which should never happen.
// We try to insert action to remove this neighbor later, but adding the action might fail as well.
NeighborhoodAction action = new NeighborhoodAction()
{
ServerId = serverId,
Timestamp = DateTime.UtcNow,
Type = NeighborhoodActionType.RemoveNeighbor,
TargetActivityId = 0,
TargetActivityOwnerId = null,
AdditionalData = null
};
await unitOfWork.NeighborhoodActionRepository.InsertAsync(action);
signalActionProcessor = true;
saveDb = true;
}
}
else
{
log.Debug("Neighbor ID '{0}' not found, can not be removed.", serverId.ToHex());
// It can be the case that this node has not an associated proximity server, so in that case we should ignore it.
// If the node has an associated proximity server, then nothing bad really happens here if we have activities
// of such a neighbor in NeighborActivity table. Those entries will expire and will be deleted.
}
break;
}
default:
log.Error("Invalid neighborhood change type '{0}'.", change.ChangeTypeCase);
break;
}
}
if (saveDb)
{
await unitOfWork.SaveThrowAsync();
transaction.Commit();
}
success = true;
res = Client.MessageBuilder.CreateNeighbourhoodChangedNotificationResponse(RequestMessage);
}
catch (Exception e)
{
log.Error("Exception occurred: {0}", e.ToString());
}
if (!success)
{
log.Warn("Rolling back transaction.");
unitOfWork.SafeTransactionRollback(transaction);
}
unitOfWork.ReleaseLock(lockObjects);
}
}
if (signalActionProcessor)
{
NeighborhoodActionProcessor neighborhoodActionProcessor = (NeighborhoodActionProcessor)Base.ComponentDictionary[NeighborhoodActionProcessor.ComponentName];
neighborhoodActionProcessor.Signal();
}
log.Trace("(-):*.Response.Status={0}", res.Response.Status);
return(res);
}
