protected override void AddEventHandlerDefinition <TEventArgs>(
RpcEventInfo eventInfo,
Func <RpcObjectRequest, IServiceProvider?, IRpcAsyncStreamWriter <TEventArgs>, IRpcContext, ValueTask> beginEventProducer,
RpcStub <TService> serviceStub,
IGrpcMethodBinder binder)
{
GrpcCore.ServerStreamingServerMethod <RpcObjectRequest, TEventArgs> handler = (request, responseStream, context) =>
{
using (var scope = CreateServiceScope(serviceStub))
{
return(beginEventProducer(request,
scope?.ServiceProvider,
new GrpcAsyncStreamWriter <TEventArgs>(responseStream),
new GrpcCallContext(context)).AsTask());
}
};
var beginEventProducerName = $"Begin{eventInfo.Name}";
binder.AddMethod(
GrpcMethodDefinition.Create <RpcObjectRequest, TEventArgs>(
GrpcCore.MethodType.ServerStreaming,
eventInfo.FullServiceName,
beginEventProducerName,
serviceStub.Serializer),
handler);
}
protected override void AddEventHandlerDefinition <TEventArgs>(
RpcEventInfo eventInfo,
Func <RpcObjectRequest, IServiceProvider?, IRpcAsyncStreamWriter <TEventArgs>, IRpcContext, ValueTask> beginEventProducer,
RpcStub <TService> serviceStub,
ILightweightMethodBinder binder)
{
var beginEventProducerName = $"{eventInfo.FullServiceName}.Begin{eventInfo.Name}";
var methodStub = new LightweightStreamingMethodStub <RpcObjectRequest, TEventArgs>(beginEventProducerName, beginEventProducer, serviceStub.Serializer, null);
binder.AddMethod(methodStub);
}
internal void AddEventHandler(RpcStub <TService> serviceStub, RpcEventInfo eventInfo, TMethodBinder binder)
{
if (typeof(EventHandler).Equals(eventInfo.Event.EventHandlerType))
{
this.AddPlainEventHandler(serviceStub, eventInfo, binder);
return;
}
// TODO: Cache.
var addEventHandlerDelegate = (Action <RpcStub <TService>, RpcEventInfo, TMethodBinder>)
GetBuilderMethod(nameof(this.AddGenericEventHandler))
.MakeGenericMethod(eventInfo.EventArgsType)
.CreateDelegate(typeof(Action <RpcStub <TService>, RpcEventInfo, TMethodBinder>), this);
addEventHandlerDelegate(serviceStub, eventInfo, binder);
}
protected override void AddEventHandlerDefinition <TEventArgs>(
RpcEventInfo eventInfo,
Func <RpcObjectRequest, IServiceProvider?, IRpcAsyncStreamWriter <TEventArgs>, IRpcContext, ValueTask> beginEventProducer,
RpcStub <TService> serviceStub,
INetGrpcBinder <TService> binder)
{
ServerStreamingServerMethod <NetGrpcServiceActivator <TService>, RpcObjectRequest, TEventArgs> handler = (activator, request, responseStream, context) =>
beginEventProducer(request, activator.ServiceProvider, new GrpcAsyncStreamWriter <TEventArgs>(responseStream), new GrpcCallContext(context)).AsTask();
var beginEventProducerName = $"Begin{eventInfo.Name}";
binder.AddServerStreamingMethod(
GrpcMethodDefinition.Create <RpcObjectRequest, TEventArgs>(
MethodType.ServerStreaming,
eventInfo.FullServiceName,
beginEventProducerName,
serviceStub.Serializer),
eventInfo.Metadata,
handler);
}
protected abstract void AddEventHandlerDefinition <TEventArgs>(
RpcEventInfo eventInfo,
Func <RpcObjectRequest, IServiceProvider?, IRpcAsyncStreamWriter <TEventArgs>, IRpcContext, ValueTask> beginEventProducer,
RpcStub <TService> serviceStub,
TMethodBinder binder)
where TEventArgs : class;
internal void AddGenericEventHandler <TEventArgs>(RpcStub <TService> serviceStub, RpcEventInfo eventInfo, TMethodBinder binder) where TEventArgs : class
{
if (eventInfo.Event.EventHandlerType == null || eventInfo.Event.AddMethod == null || eventInfo.Event.RemoveMethod == null)
{
throw new NotSupportedException($"Service event handler for '{eventInfo.DeclaringMember.Name}' must be full defined.");
}
var serviceParameter = Expression.Parameter(typeof(TService));
var delegateParameter = Expression.Parameter(typeof(Delegate));
var castDelegateExpression = Expression.Convert(delegateParameter, eventInfo.Event.EventHandlerType);
var addHandlerExpression = Expression.Call(serviceParameter, eventInfo.Event.AddMethod, castDelegateExpression);
var addHandlerAction = Expression.Lambda <Action <TService, Delegate> >(addHandlerExpression, serviceParameter, delegateParameter).Compile();
var removeHandlerExpression = Expression.Call(serviceParameter, eventInfo.Event.RemoveMethod, castDelegateExpression);
var removeHandlerAction = Expression.Lambda <Action <TService, Delegate> >(removeHandlerExpression, serviceParameter, delegateParameter).Compile();
ValueTask LocalBeginEventProducer(RpcObjectRequest request, IServiceProvider?serviceProvider, IRpcAsyncStreamWriter <TEventArgs> responseStream, IRpcContext context)
{
var eventProducer = new GenericEventHandlerProducer <TEventArgs>(responseStream, addHandlerAction, removeHandlerAction, context.CancellationToken);
return(serviceStub.BeginEventProducer(request, serviceProvider, eventProducer));
}
this.AddEventHandlerDefinition <TEventArgs>(eventInfo, LocalBeginEventProducer, serviceStub, binder);
}
