The Agile School

The WCF architecture is based on the design principles of service-oriented architecture (SOA). SOA is a framework that is used to design service-based distributed systems. In an SOA-based system, platform-independent services communicate across networked computers or computer processes. WCF implements. Explicit boundaries WCF services function using defined interfaces to identify the communications that flow outside the boundaries of the service. Independent services All WCF services are deployed and managed independently; they are independent of deployment, installation, and version issues. Also, each service interaction is independent of other interactions. Schema and contract-based communication WCF services communicate with clients by providing only the schema of the message and not its implementation classes. This helps developers change the service implementation in the future without impacting the clients. Policy-based compatibility Compatibility betw...

WCF Fundamentals Service are applications that wait for clients to communicate with them and respond to that communication. They expose the functionalities to client. Client initiate the communication. They consume the service offered by Service. Message: A message is a self-contained unit of data that may consist of seveal parts, including a body and headers. Clients & Service  communicate using XML messages. A single application can act as both a client and a service. Endpoints Messages are sent between endpoints. Endpoints are places where messages are sent or received (or both), and they define all the information required for the message exchange. A service exposes one or more application endpoints (as well as zero or more infrastructure endpoints), and the client generates an endpoint that is compatible with one of the service's endpoints. An  endpoint  describes in a standard-based way where messages should be sent, how they should be ...

WCF is a framework ( yep another framework :D ). It is a unified programming model for building service oriented applications   The WCF architecture uses message-based communication. This involves messages being sent between endpoints generated by either a service or a client. A service is an application that responds to a request, and a client is an application that initiates a request. In many cases, a single application can act as both a client and a service, depending on the situation. WCF is implemented primarily as a set of classes on top of the .NET Framework’s Common Language Runtime (CLR). Because it extends their familiar environment, WCF allows .NET developers to build service-oriented applications in a familiar way. The benefits of WCF asynchronous one-way messaging Many applications use asynchronous one-way messaging. For example, web browsers send requests to web servers and wait for replies. WCF supports asynchronous on...

After playing with Web services for so many years this was a tricky error which kept me thinking for few minutes.  Today when i tried to add WCF reference to my application it gave the following error, Error --------------------------- Microsoft Visual Studio --------------------------- Failed to update Service Reference 'XXXBusiness.Reference'. Error:The components required to enumerate Web references are not installed on this computer. Please re-install Visual Studio.(0x80004002)

This was a simple issue which baffled few brains in my project. For the past few weeks i was seeing the mails about this. What was the exact problem?  Whenever a large xml stream is passed through WCF it generated the following error. Everything was fins at the ASP.net client side. Almost all the known properties of   Problem: The maximum string content length quota (8192)  has been exceeded while reading XML data. This quota may be increased by changing the MaxStringContentLength property on the XmlDictionaryReaderQuotas object used when creating the XML reader. Cause:  By default WCF allows a string content of size 8192  (8K) to pass through without any problems. If the size increases above this set limit WCF treats the incoming message as bad message & hence throws an exception. This level was set considering the security aspect of distributed system. If we have to pass more data we will have to manually override this default setting. Now h...