You can configure the XML Parser transformation to validate XML before parsing it. The XML Parser transformation validates the XML against a schema. If the XML is not valid for the schema, a row error occurs. The XML Parser transformation returns the XML and associated error messages to a separate output group. You can pass the invalid XML and error message to a target.

For example, a real-time PowerCenter session reads XML messages from a WebSphere MQSeries source. The session runs with a source-based commit. A message in the commit transaction has an invalid XML payload. To prevent the commit from failing, you can configure the XML Parser transformation to return the invalid XML to a separate output group from the valid data. The XML Parser transformation processes the valid XML messages and completes the transaction.

The session log contains a message that indicates when Route Invalid Payload Through Data Flow is enabled. When you set the session tracing level to Normal, the Integration Service writes a message to the session log that indicates whether the validation is successful. The log message contains the location of the schema the XML Parser accessed to validate the XML. When XML streaming is enabled and the XML is invalid, the Integration Service truncates the XML and passes it to the Invalid_Payload port. The Integration Service logs the invalid XML in the session log.

To configure the XML Parser transformation to validate the XML, enable the Route Invalid Payload Through Data Flow option on the Midstream XML Parser tab. The Designer adds the following ports to the XML Parser transformation:

The following figure shows an XML Parser transformation that routes invalid XML messages to an Errors target table:

The mapping contains the following objects:

Configure the XML Schema Location attribute in the session properties for the transformation. Enter the name and location of the schema to validate the XML against. You can configure workflow, session, or mapping variables and parameters for the XML schema definition. You can configure multiple schemas for validation if you separate them with semi-colons.

You can use a DTD for validation if you include it in the input XML payload. You cannot configure a DTD in the XML Schema Location attribute or use it to route invalid XML data to the Invalid Payload port.

If you enable XML streaming, verify that the precision for the Invalid_Payload port matches the maximum message size. If the port precision is less than the message size, the XML Parser transformation returns truncated XML in the Invalid_Payload port, and writes an error in the session log.