Web Service Project Contents
A Web service project is used to access a single ClearPath application. Each ePortal client message is exposed as an object, derived from Message. A Web service method for each ePortal client message is created with a parameterized list of input fields. The methods have the form
ComponentName.Message = <prefix><ePortal client message name>(arg1, arg2…)
A call to the corresponding method passes all input field values. An object derived from Message is returned, and the MessageClassName can be interrogated to determine the type of a message returned. Any information returned from the ClearPath server application is included in this message object.
When the methods are consumed by a client, the HTTP session should be maintained if the presentation generation option, RequiresSession, is true. Refer to Presentation Generation Properties.
When a Web service project is built in the ClearPath ePortal Developer environment, the following methods are created.
Method | Action | When To Use in a Web Service Client |
|---|---|---|
Connect | Note: this method exists if, and only if, the presentation generation option IncludeConnectMethod is true. Refer to Presentation Generation Properties. This method initiates the connection to the ClearPath server application. Calling this method establishes a session on which all other calls from the Web service client can be made. | Must be the first method called, if applicable. |
Disconnect | Note: this method exists if, and only if, the presentation generation option IncludeDisconnectMethod is true. Refer to Presentation Generation Properties.
This method terminates the session with the ClearPath application. | Must be the last method called, if applicable. |
SendMessage | Note: This method sends message objects to the ClearPath server application and receives message objects from the ClearPath server application.
For every message object sent, the next message object that corresponds to a returned message is received. | Anytime between the first call and last call. |
Understanding Web Service WSDL Files
WSDL files are used to communicate interface information between Web service producers and consumers. A WSDL description allows a client to utilize the capabilities of a Web service without knowledge of the implementation details of the Web service.
A WSDL file contains the following information. This information is necessary for a Web service client to invoke the methods of a Web service:
The data types used as method parameters or return values
The individual methods names and signatures (WSDL refers to methods as operations)
The protocols and message formats allowed for each method
The URLs used to access the Web service
Optional documentation to describe the web service, web service methods, and method parameters. Refer to Choosing WCF or Web API.
The WSDL file for a Web service is available to any potential client that can reach the URL of the Web service. Refer to "XML Web Services" in the Visual Studio documentation for more details.
To obtain a WSDL file of a Web service from the ePortal Web Partition
In a browser, browse to the URL of the Web service with ?WSDL appended. For example:
http://myServer/MyProject/Service.asmx?WSDL
On the File menu of the browser, select SaveAs. The WSDL file is saved to the local system.