Simple Example

This section shows an example web service, as well as an example of a request message that it can recognize and the corresponding response message.

First, the web service is as follows:

/// MyApp.StockService
Class MyApp.StockService Extends %SOAP.WebService 
{

/// Name of the WebService.
Parameter SERVICENAME = "StockService";

/// TODO: change this to actual SOAP namespace.
/// SOAP Namespace for the WebService
Parameter NAMESPACE = "https://tempuri.org";

/// Namespaces of referenced classes will be used in the WSDL.
Parameter USECLASSNAMESPACES = 1;

/// This method returns tomorrow's price for the requested stock
Method Forecast(StockName As %String) As %Integer [WebMethod]
{
    // apply patented, nonlinear, heuristic to find new price
    Set price = $Random(1000)
    Quit price
}
}

When you invoke this method from a web client, the client sends a SOAP message to the web service. This SOAP message might look like the following (with line breaks and spaces added here for readability):

<?xml version="1.0" encoding="UTF-8" ?>
<SOAP-ENV:Envelope 
xmlns:SOAP-ENV='https://schemas.xmlsoap.org/soap/envelope/' 
xmlns:xsi='https://www.w3.org/2001/XMLSchema-instance' 
xmlns:s='https://www.w3.org/2001/XMLSchema'>
  <SOAP-ENV:Body>
    <Forecast xmlns="https://tempuri.org">
     <StockName xsi:type="s:string">GZP</StockName>
    </Forecast>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

Note that the message body (the <SOAP-ENV:Body> element) includes an element named <Forecast>, which is the name of the method that the client is invoking. The <Forecast> includes one element, <StockName>, whose name is based on the argument name of the web method that we are invoking. This element contains the actual value of this argument.

The web service performs the requested action and then sends a SOAP message in reply. The response message might look like the following:

<?xml version="1.0" encoding="UTF-8" ?>
<SOAP-ENV:Envelope 
xmlns:SOAP-ENV='https://schemas.xmlsoap.org/soap/envelope/' 
xmlns:xsi='https://www.w3.org/2001/XMLSchema-instance' 
xmlns:s='https://www.w3.org/2001/XMLSchema'>
  <SOAP-ENV:Body>
    <ForecastResponse xmlns="https://www.myapp.org">
      <ForecastResult>799</ForecastResult>
    </ForecastResponse>
  </SOAP-ENV:Body>
</SOAP-ENV:Envelope>

These examples do not include the HTTP headers that precede the SOAP message itself.

Creating a Web Service

Basic Requirements