WSDL

A WSDL document is written in XML and describes a Web service. In addition to specifying the location of the Web service, a WSDL description also specifies the methods provided by the Web service, and the messages, datatypes, and communication protocols used by the Web service with the following tags:

• <service> – defines the name of the Web service. For example, a Web service called ExecuteStoredProcService could be named as follows:

   <wsdl:service name="ExecuteStoredProcService">
    <wsdl:port binding="impl:aseSoapBinding" name="ase">
     <wsdlsoap:address location="http://myserver:8181/services/ase"/>
    </wsdl:port>
   </wsdl:service>
  

  A WSDL document may contain one or more <service> tags. In the case of the ASE Web Services Engine, there is only one service, which is named “ase.”

• <binding> – defines the communication protocols used. The following example uses the SOAP protocol:

   <wsdl:binding name="aseSoapBinding" type="impl:ExecuteStoredProc">
  ...
   </wsdl:binding>
  

  WSDL also supports use of HTTP and MIME protocols.

• <port> – specifies the Web service address. For example:

    <wsdl:port binding="impl:aseSoapBinding" name="ase">
     <wsdlsoap:address location="http://myserver:8181/services/ase"/>
    </wsdl:port>
  

  The <port> tag has attributes for name and binding.

• <message> – defines the messages used. For example:

   <wsdl:message name="executeRequest">
    <wsdl:part name="service" type="xsd:string"/>
    <wsdl:part name="userName" type="xsd:string"/>
    <wsdl:part name="password" type="xsd:string"/>
    <wsdl:part name="sqlxOptions" type="xsd:string"/>
    <wsdl:part name="sql" type="xsd:string"/>
   </wsdl:message>
  

  This is a request message for a method called executeRequest. The <part> tags correspond to parameter values for the method call in a request message and to return values in a response.

• <operation> – associates a message with a Web method request or response. For example:

    <wsdl:operation name="execute" parameterOrder="service userName
     password sqlxOptions sql">
     <wsdl:input message="impl:executeRequest" name="executeRequest"/>
     <wsdl:output message="impl:executeResponse" name="executeResponse"/>
    </wsdl:operation>
  
  

• <portType> – defines the methods provided. The <operation> tag is a child element of <portType>. For example:

   <wsdl:portType name="ExecuteStoredProc">
    <wsdl:operation name="execute" parameterOrder="aseServerName asePortNumber
  ....
    </wsdl:operation>
   </wsdl:portType>
  

• <types> – defines the datatypes used. WSDL uses XML schema syntax to define datatypes.

WSDL is usually automatically generated by the ASE Web Services Engine and can be viewed in a Web browser at the following location:

http://myserver:producer_port/services/ase?wsdl

where:

• myserver – is the name of the host on which the ASE Web Services Engine is running,

• producer_port – is the port number.