public ListenerScanner(IReqResBus messageBus, ILogger logger)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
_logger = logger ?? messageBus.Logger;
_builder = new UntypedListenerBuilder(messageBus);
}
/// <summary>
/// Setup round-robin distribution rules for Request/Response channels
/// </summary>
/// <typeparam name="TRequest"></typeparam>
/// <typeparam name="TResponse"></typeparam>
/// <param name="messageBus"></param>
/// <param name="inTopics"></param>
/// <param name="outTopics"></param>
/// <returns></returns>
public static IDisposable SetupRequestDistribution <TRequest, TResponse>(this IReqResBus messageBus, string inTopics, IEnumerable <string> outTopics)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
var rule = new RoundRobinDistributeRule <TRequest>(outTopics);
return(messageBus.RequestRouter.AddRequestRouteRule <TRequest, TResponse>(inTopics, rule));
}
public ListenerBuilder(IReqResBus messageBus, IWorkerPool workerPool)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
Assert.ArgumentNotNull(workerPool, nameof(workerPool));
_messageBus = messageBus;
_workerPool = workerPool;
}
public static IRequest <TResponse> Request <TRequest, TResponse>(this IReqResBus messageBus, string topic, TRequest requestPayload)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
var envelope = messageBus.EnvelopeFactory.Create(topic, requestPayload);
return(messageBus.RequestEnvelope <TRequest, TResponse>(envelope));
}
/// <summary>
/// Setup rules to route the Request/Response channel by inspecting the contents of the request payload
/// </summary>
/// <typeparam name="TRequest"></typeparam>
/// <typeparam name="TResponse"></typeparam>
/// <param name="messageBus"></param>
/// <param name="inTopic"></param>
/// <param name="getTopic"></param>
/// <returns></returns>
public static IDisposable SetupRequestByExamination <TRequest, TResponse>(this IReqResBus messageBus, string inTopic, Func <TRequest, string> getTopic)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
Assert.ArgumentNotNull(getTopic, nameof(getTopic));
var rule = new PayloadExamineRule <TRequest>(getTopic);
return(messageBus.RequestRouter.AddRequestRouteRule <TRequest, TResponse>(inTopic, rule));
}
/// <summary>
/// Build a listener to handle requests of the given type using common options.
/// </summary>
/// <typeparam name="TRequest">The type of the request object</typeparam>
/// <typeparam name="TResponse">The type of the response object</typeparam>
/// <param name="messageBus">The message bus</param>
/// <param name="build">The lambda function to build the listener</param>
/// <returns>A token representing the subscription whic, when disposed, cancels the subscription</returns>
public static IDisposable Listen <TRequest, TResponse>(this IReqResBus messageBus, Action <ITopicListenerBuilder <TRequest, TResponse> > build)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
var builder = new ListenerBuilder <TRequest, TResponse>(messageBus, messageBus.WorkerPool);
build(builder);
var listener = builder.BuildListener();
var token = messageBus.Listen(builder.Topic, listener);
return(builder.WrapToken(token));
}
/// <summary>
/// Add predicate-based routing rules for Request/Response operations
/// </summary>
/// <typeparam name="TRequest"></typeparam>
/// <typeparam name="TResponse"></typeparam>
/// <param name="messageBus"></param>
/// <param name="build"></param>
/// <returns></returns>
public static IDisposable SetupRequestRouting <TRequest, TResponse>(this IReqResBus messageBus, Action <IFilterRouteBuilderSingleInput <TRequest> > build)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
Assert.ArgumentNotNull(build, nameof(build));
var builder = new FilterRouteBuilder <TRequest>();
build(builder);
var router = builder.Build();
return(messageBus.RequestRouter.AddRequestRouteRule <TRequest, TResponse>(builder.InTopics.FirstOrDefault(), router));
}
private static IDisposable BuildListener(IReqResBus messageBus, Func <TRequest, TResponse> func, Action <IThreadListenerBuilder <TRequest, TResponse> > build, string topic)
{
var token = messageBus.Listen <TRequest, TResponse>(b =>
{
var c = b
.WithTopic(topic)
.Invoke(func);
build?.Invoke(c);
});
return(token);
}
public WrappedFunction <TRequest, TResponse> WrapFunction(IReqResBus messageBus, Func <TRequest, TResponse> func, Action <IThreadListenerBuilder <TRequest, TResponse> > build)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
Assert.ArgumentNotNull(func, nameof(func));
var topic = Guid.NewGuid().ToString();
var token = BuildListener(messageBus, func, build, topic);
var newFunc = BuildFunction(messageBus, topic);
return(new WrappedFunction <TRequest, TResponse>(newFunc, token, topic));
}
/// <summary>
/// Make a request for cases where the type of request is not known until runtime. The bus
/// attempts to infer the response type from metadata, and performs the request if possible.
/// The request type must inherit from <see cref="IRequestWithResponse{TResponse}"/> in order to make
/// the necessary type inferences.
/// </summary>
/// <param name="messageBus">The message bus</param>
/// <param name="topic">The name of the channel</param>
/// <param name="requestType">The runtime type of the request</param>
/// <param name="request">The request object</param>
/// <returns>The response object</returns>
public static object Request(this IReqResBus messageBus, string topic, Type requestType, object request)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
var requestInterface = requestType.GetInterfaces().FirstOrDefault(i => i.IsGenericType && i.GetGenericTypeDefinition() == typeof(IRequestWithResponse <>));
if (requestInterface == null)
{
return(null);
}
var factoryMethod = messageBus.EnvelopeFactory.GetType()
.GetMethod(nameof(messageBus.EnvelopeFactory.Create))
.MakeGenericMethod(requestType);
var envelope = factoryMethod.Invoke(messageBus.EnvelopeFactory, new[] { new [] { topic }, request, null });
var responseType = requestInterface.GetGenericArguments().Single();
var method = messageBus.GetType().GetMethod(nameof(messageBus.RequestEnvelope)).MakeGenericMethod(requestType, responseType);
var waiter = (Request)method.Invoke(messageBus, new[] { envelope });
waiter.WaitForResponse();
waiter.ThrowExceptionIfError();
return(waiter.GetResponseObject());
}
private static Func <TRequest, TResponse> BuildFunction(IReqResBus messageBus, string topic)
{
TResponse NewFunc(TRequest req) => messageBus.RequestWait <TRequest, TResponse>(topic, req);
return(NewFunc);
}
public static Task <TResponse> RequestAsync <TRequest, TResponse>(this IReqResBus messageBus, TRequest requestPayload)
{
var request = Request <TRequest, TResponse>(messageBus, requestPayload);
return(request.GetResponseAsync());
}
public static TResponse RequestWait <TRequest, TResponse>(this IReqResBus messageBus, TRequest requestPayload)
{
return(Request <TRequest, TResponse>(messageBus, requestPayload).GetResponseOrWait());
}
/// <summary>
/// Make a request of the given type on the default channel
/// </summary>
/// <typeparam name="TRequest">The type of request object</typeparam>
/// <typeparam name="TResponse">The type of response object</typeparam>
/// <param name="messageBus">The message bus</param>
/// <param name="requestPayload">The request object, which represents the input arguments to the RPC</param>
/// <returns>A token representing the subscription which, when disposed, cancels the subscription</returns>
public static IRequest <TResponse> Request <TRequest, TResponse>(this IReqResBus messageBus, TRequest requestPayload)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
return(messageBus.Request <TRequest, TResponse>(string.Empty, requestPayload));
}
public static IDisposable ListenEnvelopeUntyped(this IReqResBus messageBus, Type requestType, Type responseType, string topic, object target, MethodInfo listener, bool useWeakReferences = false)
{
return(new UntypedListenerBuilder(messageBus).ListenEnvelopeUntyped(requestType, responseType, topic, target, listener, useWeakReferences));
}
public UntypedListenerBuilder(IReqResBus messageBus)
{
_messageBus = messageBus;
}
public static WrappedFunction <TRequest, TResponse> WrapFunction <TRequest, TResponse>(this IReqResBus messageBus, Func <TRequest, TResponse> func, Action <IThreadListenerBuilder <TRequest, TResponse> > build)
{
return(new RequestFuncWrapper <TRequest, TResponse>().WrapFunction(messageBus, func, build));
}
/// <summary>
/// Get a typed request channel to simplify request/response calls
/// </summary>
/// <typeparam name="TRequest"></typeparam>
/// <typeparam name="TResponse"></typeparam>
/// <param name="messageBus"></param>
/// <returns></returns>
public static RequestChannelProxy <TRequest, TResponse> GetRequestChannel <TRequest, TResponse>(this IReqResBus messageBus)
{
return(new RequestChannelProxy <TRequest, TResponse>(messageBus));
}
public RequestChannelProxy(IReqResBus messageBus)
{
Assert.ArgumentNotNull(messageBus, nameof(messageBus));
_messageBus = messageBus;
}
public static IDisposable AutoWireupListeners(this IReqResBus messageBus, object obj, bool useWeakReferences = false)
{
var tokens = new ListenerScanner(messageBus, messageBus.Logger).DetectAndWireUpAll(obj, useWeakReferences);
return(new DisposableCollection(tokens));
}
public static IDisposable ListenUntyped(this IReqResBus messageBus, Type requestType, Type responseType, string topic, Func <object, object> handle, bool useWeakReferences = false)
{
return(new UntypedListenerBuilder(messageBus).ListenUntyped(requestType, responseType, topic, handle, useWeakReferences));
}
