Validate Mediator

The Valiade Mediator is used for schema validation of messages.

The portion of the message that needs to be validated is choosen by evaluating the XPath expression. Then this message is validated against the schema specified. User can specify a sequence to be executed in case of a validation failure. This mediator provides an extension point by providing properties to configure the underline validation engine.

Syntax

<validate [source="xpath"]>
   <property name="validation-feature-id" value="true|false"/>*
   <schema key="string"/>+
   <on-fail>
     mediator+
   </on-fail>
 </validate>

The Validate Mediator validates the result of the evaluation of the source XPath expression, against the schema specified. If the source attribute is not specified, the validation is performed against the first child of the SOAP body of the current message. If the validation fails, the on-fail sequence of mediators is executed. Properties could be used to turn on/off some of the features of the validator.

UI Configuration

• Key - Schema location. It can  be chosen either from Configuration Registry or Governance Registry. See more information about the Registry Browser in Registry Browser and Namespace.

  Tip

  To add a new Schema Key, use the "Add New Schema Key" link.

• Source - XPath expression to extract the XML that need to be validated. If not specified, validation is performed against the first child of the SOAP body.

  Tip

  You can click this link to add namespaces if you are providing an expression. You will be provided another panel named "Namespace Editor," where you can provide any number of namespace prefixes and URL that you have used in the XPath expression.

• Features 
  • Feature Name

  • Action - Delete.

    Note

    Here is the only mandatory feature supported by the validator.  For more information look at http://java.sun.com/javase/6/docs/api/constant-values.html#javax.xml.XMLConstants.FEATURE_SECURE_PROCESSING

Example

<validate>
    <schema key="schema\sample.xsd"/>
         <on-fail>
                <makefault>
                    <code value="tns:Receiver"
                            xmlns:tns="http://www.w3.org/2003/05/soap-envelope"/>
                    <reason value="Invalid Request!!!"/>
                </makefault>
                <property name="RESPONSE" value="true"/>
                <header name="To" expression="get-property('ReplyTo')"/>
         </on-fail>
</validate>

In the above Validate Mediator configuration the required schema for validating message going through the validate mediator has been given as a registry key, schema\sample.xsd. In this sample configuration, there is no source attribute. Therefore, in this case, the Validate Mediator takes source as the first child of SOAP Body. Within on-fail it is possible to specify mediation logic that should to be happened if the validation is failed. In the above configuration it creates a SOAP fault using makefault mediator and send back that to requested party.