/// <summary>
/// Selects a <see cref="EventHandlerDescriptor"/> for the given <see cref="HandlerRequest"/>.
/// </summary>
/// <param name="request">The request.</param>
/// <returns>An <see cref="EventHandlerDescriptor"/> instance.</returns>
public EventHandlersDescriptor SelectHandlers(EventHandlerRequest request)
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
EventHandlersDescriptor result;
if (!this.handlerInfoCache.Value.TryGetValue(request.MessageType, out result))
{
throw Error.InvalidOperation(Resources.DefaultHandlerSelector_HandlerNotFound, request.MessageType.Name);
}
return result;
}
/// <summary>
/// Selects a <see cref="EventHandlerDescriptor"/> for the given <see cref="HandlerRequest"/>.
/// </summary>
/// <param name="request">The request.</param>
/// <returns>An <see cref="EventHandlerDescriptor"/> instance.</returns>
public EventHandlersDescriptor SelectHandlers(EventHandlerRequest request)
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
EventHandlersDescriptor result;
if (!this.handlerInfoCache.Value.TryGetValue(request.MessageType, out result))
{
throw Error.InvalidOperation(Resources.DefaultHandlerSelector_HandlerNotFound, request.MessageType.Name);
}
return(result);
}
/// <summary>
/// Execute the request via the worker.
/// </summary>
/// <param name="request">The <see cref="EventHandlerRequest"/> to execute.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> to cancel the execution.</param>
/// <returns>The <see cref="Task"/> of the event.</returns>
public async Task PublishAsync(EventHandlerRequest request, CancellationToken cancellationToken)
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
IEventHandlerSelector handlerSelector = this.Configuration.Services.GetEventHandlerSelector();
EventHandlersDescriptor eventDescriptor = handlerSelector.SelectHandlers(request);
var descriptors = eventDescriptor.EventHandlerDescriptors;
for (int i = 0; i < descriptors.Count; i++)
{
await InvokeHandlerAsync(descriptors[i], request, cancellationToken);
}
}
/// <summary>
/// Execute the request via the worker.
/// </summary>
/// <param name="request">The <see cref="EventHandlerRequest"/> to execute.</param>
/// <param name="cancellationToken">The <see cref="CancellationToken"/> to cancel the execution.</param>
/// <returns>The <see cref="Task"/> of the event.</returns>
public async Task PublishAsync(EventHandlerRequest request, CancellationToken cancellationToken)
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
IEventHandlerSelector handlerSelector = this.Configuration.Services.GetEventHandlerSelector();
EventHandlersDescriptor eventDescriptor = handlerSelector.SelectHandlers(request);
var descriptors = eventDescriptor.EventHandlerDescriptors;
for (int i = 0; i < descriptors.Count; i++)
{
await InvokeHandlerAsync(descriptors[i], request, cancellationToken);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="CommandHandlerContext"/> class.
/// </summary>
/// <param name="request">The handler request.</param>
/// <param name="descriptor">The handler descriptor.</param>
public EventHandlerContext(EventHandlerRequest request, EventHandlerDescriptor descriptor)
: this()
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
if (request.Configuration == null)
{
throw Error.Argument("request");
}
this.Configuration = request.Configuration;
this.Request = request;
this.Event = request.Event;
this.Descriptor = descriptor;
this.User = this.Configuration.Services.GetPrincipalProvider().Principal;
}
/// <summary>
/// Initializes a new instance of the <see cref="CommandHandlerContext"/> class.
/// </summary>
/// <param name="request">The handler request.</param>
/// <param name="descriptor">The handler descriptor.</param>
public EventHandlerContext(EventHandlerRequest request, EventHandlerDescriptor descriptor)
: this()
{
if (request == null)
{
throw Error.ArgumentNull("request");
}
if (request.Configuration == null)
{
throw Error.Argument("request");
}
this.Configuration = request.Configuration;
this.Request = request;
this.Event = request.Event;
this.Descriptor = descriptor;
this.User = this.Configuration.Services.GetPrincipalProvider().Principal;
}
private static Task InvokeHandlerAsync(EventHandlerDescriptor descriptor, EventHandlerRequest request, CancellationToken cancellationToken)
{
Contract.Requires(descriptor != null);
Contract.Requires(request != null);
IEventHandler handler = descriptor.CreateHandler(request);
if (handler == null)
{
throw CreateHandlerNotFoundException(descriptor);
}
request.RegisterForDispose(handler, true);
EventHandlerContext context = new EventHandlerContext(request, descriptor);
context.Handler = handler;
handler.EventContext = context;
EventFilterGrouping filterGrouping = descriptor.GetFilterGrouping();
ServicesContainer servicesContainer = request.Configuration.Services;
IEventHandlerResult result = new EventHandlerFilterResult(context, servicesContainer, filterGrouping.EventHandlerFilters);
return result.ExecuteAsync(cancellationToken);
}
private static Task InvokeHandlerAsync(EventHandlerDescriptor descriptor, EventHandlerRequest request, CancellationToken cancellationToken)
{
Contract.Requires(descriptor != null);
Contract.Requires(request != null);
IEventHandler handler = descriptor.CreateHandler(request);
if (handler == null)
{
throw CreateHandlerNotFoundException(descriptor);
}
request.RegisterForDispose(handler, true);
EventHandlerContext context = new EventHandlerContext(request, descriptor);
context.Handler = handler;
handler.EventContext = context;
EventFilterGrouping filterGrouping = descriptor.GetFilterGrouping();
ServicesContainer servicesContainer = request.Configuration.Services;
IEventHandlerResult result = new EventHandlerFilterResult(context, servicesContainer, filterGrouping.EventHandlerFilters);
return(result.ExecuteAsync(cancellationToken));
}
/// <summary>
/// Creates a handler instance for the given <see cref="HandlerRequest"/>.
/// </summary>
/// <param name="request">The request.</param>
/// <returns>The created handler instance.</returns>
public virtual IEventHandler CreateHandler(EventHandlerRequest request)
{
return(this.handlerActivator.Create(request, this));
}
