public override RequestInvocationHandle InvokeRequest(IRequestDescriptor <IHandlerDescriptor?> descriptor, Request request)
{
if (descriptor.Default is null)
{
throw new ArgumentNullException(nameof(descriptor.Default));
}
var handle = new RequestInvocationHandle(request);
var type = _requestProcessIdentifier.Identify(descriptor.Default);
var schedulerDelegate = RouteRequest(descriptor, request, handle);
_processScheduler.Add(type, $"{request.Method}:{request.Id}", schedulerDelegate);
return(handle);
}
private SchedulerDelegate RouteRequest(
IRequestDescriptor <IHandlerDescriptor?> descriptor,
Request request,
RequestInvocationHandle handle)
{
var cts = handle.CancellationTokenSource;
return((contentModifiedToken, scheduler) =>
Observable.Create <ErrorResponse>(
observer => {
// ITS A RACE!
var sub = Observable.Amb(
contentModifiedToken.Select(
_ => {
_logger.LogTrace(
"Request {Id} was abandoned due to content be modified", request.Id
);
return new ErrorResponse(
new ContentModified(request.Id, request.Method)
);
}
),
Observable.Timer(_options.RequestTimeout, scheduler).Select(
_ => new ErrorResponse(new RequestCancelled(request.Id, request.Method))
),
Observable.FromAsync(
async ct => {
using var timer = _logger.TimeDebug(
"Processing request {Method} {ResponseId}", request.Method,
request.Id
);
ct.Register(cts.Cancel);
// ObservableToToken(contentModifiedToken).Register(cts.Cancel);
try
{
var result = await _requestRouter.RouteRequest(
descriptor, request, cts.Token
).ConfigureAwait(false);
return result;
}
catch (OperationCanceledException)
{
_logger.LogTrace("Request {Id} was cancelled", request.Id);
return new RequestCancelled(request.Id, request.Method);
}
catch (RpcErrorException e)
{
_logger.LogCritical(
Events.UnhandledRequest, e,
"Failed to handle request {Method} {RequestId}", request.Method,
request.Id
);
return new RpcError(
request.Id, request.Method,
new ErrorMessage(e.Code, e.Message, e.Error)
);
}
catch (Exception e)
{
_logger.LogCritical(
Events.UnhandledRequest, e,
"Failed to handle request {Method} {RequestId}", request.Method,
request.Id
);
return new InternalError(request.Id, request.Method, e.ToString());
}
}
)
)
.Subscribe(observer);
return new CompositeDisposable(sub, handle);
}
)
.Select(
response => {
_outputHandler.Send(response.Value);
return Unit.Default;
}
));
}
