Building an XML Web service with an ATL Server

--visual Studio in the next version of Visual studio®. NET will include an application called an ATL Server for C + + programmers, which greatly simplifies the development of high-performance, scalable Web applications. The ATL server provides a set of classes that extend the Active Template Library (ATL) to access all of the functionality of IIS through ISAPI. The classes provided by the ATL Server enable developers to easily handle issues such as buffering, thread-pool, and session state. By making the template Library lightweight, scalable, and leveraging ATL's "work only for what is needed" model, it enables developers to gain the performance of ISAPI heights in a very short time. For more comprehensive information on ATL servers, read the article: ATL Server: Creating High-performance Web Applications with Visual C + +. An important part of the ATL Server architecture is that it is ideal for efficiently processing XML Web service requests. Because this template library is extended to support XML Web services, this enables organizations to quickly and efficiently expose enterprise logic as XML Web services. Using disco files, ATL Server Web services are easily published and positioned via the Soap/xml protocol. The ATL Server Web service can be invoked in any language that is run on any platform through the HTTP protocol. This extends the programming capability through the firewall to the remote client.

Creating an XML Web service in ATL

Select the "Create as Web Service" checkbox (in Application Options) in the ATL Server Application Wizard to create an XML Web service on an ATL server by using the ATL Server Web Service Engineering Wizard. (Note that the ATL Server Web Service Engineering Wizard runs the ATL Server Engineering Wizard, except that the "Create as Web service" check box is selected by default.) ）

Figure 1. ATL Server Wizard check box

The Create as Web Service check box generates a standard ATL Server application with the default XML Web service named "HelloWorld." The HelloWorld function demonstrates how to create a basic ATL Server Web service.

The following code explains what happened in the wizard that generated the source file.

We need to implement the class for this interface. This class must implement the methods of the interfaces that have been written. An XML Web service is marked with two properties. The first, [Soap_handler], is placed in the class, indicating that the property provider (the application that is responsible for providing the code will be inserted as a substitute for the property) will handle the SOAP request. The second, [Soap_method], is used to mark a method that is exposed as an XML Web service and indicates that the property provider this method will be used to receive and send SOAP messages (that is, we need to decode and encode the input and output of this method).

You can build and deploy the XML Web services that the wizard creates, but you cannot use this service unless you have an XML Web service client.