Programming WCF Services, 3rd Edition

Request-Reply Operations

All the samples in the previous chapters included contracts whose operations were of the type known as request-reply. As the name implies, in these operations, the client issues a request in the form of a message and blocks until it gets the reply message. If the service does not respond within a default timeout of one minute, the client will get a TimeoutException. Request-reply is the default operation mode. Programming against request-reply operations is simple enough and resembles programming using the classic client/server model. The returned response message containing the results or returned values is converted to normal method return values. In addition, the proxy will throw an exception on the client side if there are any communication or service-side exceptions. Apart from the NetPeerTcpBinding and the NetMsmqBinding, all bindings support request-reply operations.