• Introducing JBI
  • What is JBI?
  • JBI MEPs
  • JBI API
• JBI Components
  • servicemix-bean
  • servicemix-camel
  • servicemix-cxf-bc
  • servicemix-cxf-se
  • servicemix-drools
  • servicemix-eip
  • servicemix-exec
  • servicemix-file
  • servicemix-ftp
  • servicemix-http
  • servicemix-jms
  • servicemix-mail
  • servicemix-osworkflow
  • servicemix-quartz
  • servicemix-saxon
  • servicemix-scripting
  • servicemix-snmp
  • servicemix-validation
  • servicemix-vfs
  • servicemix-wsn2005
  • servicemix-xmpp

servicemix-saxon

Overview

The servicemix-saxon component is a standard JBI Service Engine for XSLT / XQuery. This component is based on Saxon and supports XSLT 2.0 and XPath 2.0, and XQuery 1.0.

Namespace and xbean.xml

The namespace URI for the servicemix-bean JBI component is http://servicemix.apache.org/saxon/1.0. This is an example of xbean.xml file with a namespace definition with prefix saxon.

    <beans xmlns:saxon="http://servicemix.apache.org/saxon  /1.0">

      <!-- add saxon:xslt, saxon:xquery or saxon:proxy definitions here -->

    </beans>

Endpoint types

The servicemix-saxon component defines these endpoints:

• saxon:xslt: Translates the in message content using XSLT to send back the translated content in the out message

• saxon:proxy: Acts as a proxy for an endpoint, translating the message passed to/from the endpoint using XSLT

• saxon:xquery: Use xquery to extract parts of the XML

Endpoint saxon:xslt

The XSLT endpoint can be used to apply an XSLT stylesheet to the incoming exchange and will return the transformed result as the output message.

<saxon:xslt service="test:xslt" endpoint="endpoint"
            resource="classpath:transform.xsl" />

Endpoint properties

Mandatory properties

The endpoint requires one of these two properties to be specified:

Optional properties

Using properties and parameters

All properties defined on the JBI exchange and input JBI message will be available for use inside the XSLT stylesheet as parameters.

In addition to those properties and the one specified in the parameters property on the endpoint, the following objects are also available:

• exchange : the JBI exchange

• in : the input JBI NormalizedMessage

• component : the XsltEndpoint instance being called

Below is an example that demonstrates how the properties of the exchange and normalized message can be accessed from inside the xslt.

<?xml version="1.0" encoding="windows-1253"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0"
                xmlns:class="http://saxon.sf.net/java-type"
                xmlns:me="java:javax.jbi.messaging.MessageExchange"
                xmlns:nm="java:javax.jbi.messaging.NormalizedMessage">
    <xsl:output method="xml" indent="yes" encoding="ISO-8859-1"/>
    <xsl:param name="exchange" as="class:javax.jbi.messaging.MessageExchange"/>
    <xsl:param name="in" as="class:javax.jbi.messaging.NormalizedMessage"/>

    <xsl:template match="/">
    <message>
        <!-- The value of messageId will be read from thr property MSG_ID of the "in" NormalizedMessage -->
        <messageId>
            <xsl:value-of select="nm:getProperty($in, 'MSG_ID')"/>
        </messageId>
    </message>
</xsl:stylesheet>    

All those parameters can be accessed using XSLT standard ways using <xsl:param/>.

Endpoint saxon:proxy

One common use case is the need to transform a request coming from a service and send it to another service and do the same with the response. A simple example is the need to translate the request and responses between two SOAP endpoints. Such a use case could be implemented using two XSLT endpoints and an EIP StaticRoutingSlip. However, there are some drawbacks, as the operation is lost in the process, and a static routing slip can not be used to process InOnly exchanges.

<saxon:proxy service="test:proxy" endpoint="endpoint"
             resource="classpath:transform-in.xsl"
             outResource="classpath:transform-out.xsl"
             faultResource="classpath:transform-fault.xsl">
  <saxon:target>
    <saxon:exchange-target service="test:echo" />
  </saxon:target>
</saxon:proxy>

Endpoint properties

Mandatory properties

Depending on the MEP, you have to set one or more XSL stylesheets to be used for converting the message payloads:

You also have to specify the target service that should be invoked from this endpoint:

• target : ExchangeTarget that specifies the target service for the proxy endpoint

Optional properties

Endpoint saxon:xquery

The XQuery endpoint can be used to apply a selected XQuery to the input document.

<saxon:xquery service="test:xquery" endpoint="endpoint"
              resource="classpath:query.xq" />

Endpoint properties

Mandatory properties

You need to specify one of query, resource or expression

Optional properties

Sample configurations

Dynamic stylesheet selection (saxon:xslt)

This endpoint configuration will dynamically load the XSL-T resource that is specified in the xslt.source property on the NormalizedMessage

<saxon:xslt service="test:xslt-dynamic" endpoint="endpoint">
  <saxon:expression>
    <bean class="org.apache.servicemix.expression.PropertyExpression">
      <property name="property" value="xslt.source" />
    </bean>
  </saxon:expression>
</saxon:xslt>

Using parameters in the XSL-T stylesheet (saxon:xslt)

You can define a Map of parameters on the saxon:xslt endpoint.

<saxon:xslt service="test:xslt-params" endpoint="endpoint"
            resource="classpath:parameter-test.xsl">
  <property name="parameters">
    <map>
      <entry key="stringParam" value="cheeseyCheese"/>
      <entry key="integerParam">
        <bean class="java.lang.Integer">
          <constructor-arg index="0" value="4002"/>
        </bean>
      </entry>
    </map>
  </property>
</saxon:xslt>

In the XSL file, you can access the parameter values with <xsl:param/>. You can also access headers on the NormalizedMessage (like e.g. org.apache.servicemix.file) with the same syntax.

<xsl:stylesheet xmlns:xsl='http://www.w3.org/1999/XSL/Transform' version='1.0'>
  <xsl:param name="stringParam"/>
  <xsl:param name="integerParam"/>
  <xsl:param name="org.apache.servicemix.file" />
  ...
</xsl:stylesheet>

Inlined XQuery and specific output configuration (saxon:xquery)

<saxon:xquery service="test:xquery-inline" endpoint="endpoint">
  <saxon:query>
    for $x in /bookstore/book
    where $x/price > 30
    return $x/title
  </saxon:query>
  <saxon:outputProperties>
    <saxon:property key="{http://saxon.sf.net/}wrap-result-sequence">yes</saxon:property>
  </saxon:outputProperties>
</saxon:xquery>

Dynamic XQuery selection (saxon:xquery)

This endpoint configuration will dynamically load the XQuery resource that is specified in the xquery.source property on the NormalizedMessage

<saxon:xquery service="test:xquery-dynamic" endpoint="endpoint">
  <saxon:expression>
    <bean class="org.apache.servicemix.expression.PropertyExpression">
      <property name="property" value="xquery.source" />
    </bean>
  </saxon:expression>
</saxon:xquery>