/// <summary>
/// This method executes the request against the command collection.
/// </summary>
/// <param name="request">The request state.</param>
private async Task TransmitResponses(TransmissionPayloadState request)
{
//Set the follow on security.
request.Responses
.Where((p) => p.SecurityPrincipal == null)
.ForEach((p) => p.SecurityPrincipal = Thread.CurrentPrincipal as ClaimsPrincipal);
//Get the payloads that can be processed internally.
var internalPayload = request.Responses
.Where((p) => ((request.CurrentOptions & ProcessOptions.RouteInternal) > 0) && mCommands.Resolve(p))
.ToList();
//OK, send the payloads off to the Task Manager for processing.
internalPayload.ForEach((p) =>
{
//Mark internal only to stop any looping.
//We can do this as we have checked with the command handler that they will be processed
p.Options = ProcessOptions.RouteInternal;
mTaskManager.ExecuteOrEnqueue(p, "Dispatcher");
});
//Extract the payloads that have been processed internally so that we only have the external payloads left
var externalPayload = request.Responses.Except(internalPayload).ToList();
//Send the external payload to their specific destination in paralle;.
await Task.WhenAll(externalPayload.Select(async(p) => await TransmitPayload(p, request)));
}
/// <summary>
/// This method executes the request against the command collection.
/// </summary>
/// <param name="request">The request state.</param>
private async Task ExecuteCommands(TransmissionPayloadState request)
{
try
{
request.ExecuteSuccess = await mCommands.Execute(request.Payload, request.Responses);
}
catch (Exception ex)
{
request.Ex = ex;
}
//All good.
if (request.ExecuteSuccess)
{
return;
}
//Switch the incoming message to the outgoing collection to be processed
//by the sender as it has not been processed internally. This will happen if it
//is not marked as internal only and cannot be resolved locally.
if (!request.InternalOnly)
{
//OK, we are going to send this to the senders, first make sure that this doesn't route back in.
request.CurrentOptions = ProcessOptions.RouteExternal;
//Switch the incoming message to the response payload so that they are picked up by the senders.
request.Responses.Add(request.Payload);
return;
}
ProcessUnhandledPayload(Policies.Microservice.DispatcherUnresolvedRequestMode
, DispatcherRequestUnresolvedReason.MessageHandlerNotFound
, request.Payload);
}
/// <summary>
/// This method transits a payload and captures and exceptions.
/// </summary>
/// <param name="payload">The payload to process.</param>
/// <param name="request">The request state.</param>
private async Task TransmitPayload(TransmissionPayload payload, TransmissionPayloadState request)
{
try
{
request.TransmitSuccess &= await Send(payload);
}
catch (Exception ex)
{
request.Ex = ex;
request.TransmitSuccess = false;
}
}
/// <summary>
/// This method executes the request against the command collection.
/// </summary>
/// <param name="request">The request state.</param>
private async Task ExecuteCommands(TransmissionPayloadState request)
{
try
{
request.ExecuteSuccess = await mCommands.Execute(request.Payload, request.Responses);
}
catch (Exception ex)
{
request.Ex = ex;
}
//All good.
if (request.ExecuteSuccess)
{
return;
}
//Switch the incoming message to the outgoing collection to be processed
//by the sender as it has not been processed internally. This will happen if it
//is not marked as internal only and cannot be resolved locally.
if (!request.InternalOnly)
{
//OK, we are going to send this to the senders, first make sure that this doesn't route back in.
request.CurrentOptions = ProcessOptions.RouteExternal;
//Switch the incoming message to the response payload so that they are picked up by the senders.
request.Responses.Add(request.Payload);
return;
}
//OK, we have an problem. We log this as an error and get out of here.
mDataCollection.DispatcherPayloadUnresolved(request.Payload, DispatcherRequestUnresolvedReason.MessageHandler);
//Raise an event for the unresolved wrapper
mEventsWrapper.OnProcessRequestUnresolved(request.Payload, DispatcherRequestUnresolvedReason.MessageHandler);
switch (Policy.Microservice.DispatcherUnhandledMode)
{
case DispatcherUnhandledMessageAction.Ignore:
//request.IsSuccess = !request.IsFaulted;
break;
case DispatcherUnhandledMessageAction.AttemptResponseFailMessage:
//request.IsSuccess = true;
break;
case DispatcherUnhandledMessageAction.Exception:
//request.IsSuccess = true;
break;
}
}
/// <summary>
/// This is the core method that messages are sent to to be routed and processed.
/// You can override this task in your service to help debug the messages that are passing
/// though.
/// </summary>
/// <param name="requestPayload">The request payload.</param>
protected virtual async Task Execute(TransmissionPayload requestPayload)
{
var request = new TransmissionPayloadState(requestPayload
, Policy.Microservice.DispatcherTransitCountMax
, StatisticsInternal.ActiveIncrement());
try
{
Thread.CurrentPrincipal = request.Payload.SecurityPrincipal;
mEventsWrapper.OnExecuteBegin(request);
//Validate the imcoming request is correct and not cancelled.
request.IncomingValidate();
//Log the telemtry for the incoming message.
mDataCollection.DispatcherPayloadIncoming(request.Payload);
//Check that we have not exceeded the maximum transit count.
request.IncrementAndVerifyDispatcherTransitCount();
//Shortcut for external messages - send straight out
if (request.ExternalOnly)
{
await TransmitPayload(request.Payload, request);
}
else
{
//Execute the message against the internal commands
await ExecuteCommands(request);
//OK, do we have any response from the commands to send on, both internal and external messages?
if (request.Responses.Count > 0)
{
await TransmitResponses(request);
}
}
}
catch (DispatcherException dex)
{
mDataCollection.DispatcherPayloadException(dex.Payload, dex);
mEventsWrapper.OnProcessRequestError(dex.Payload, dex);
}
catch (Exception ex)
{
mDataCollection.DispatcherPayloadException(request.Payload, ex);
mEventsWrapper.OnProcessRequestError(request.Payload, ex);
}
finally
{
//Signal to the underlying listener that the message can be released.
request.Signal();
int delta = StatisticsInternal.ActiveDecrement(request.TimerStart);
//Log the telemtry for the specific message channelId.
mDataCollection.DispatcherPayloadComplete(request.Payload, delta, request.IsSuccess());
if (!request.IsSuccess())
{
StatisticsInternal.ErrorIncrement();
}
mEventsWrapper.OnExecuteComplete(request);
//Set the thread principal to null before leaving.
Thread.CurrentPrincipal = null;
}
}
