Spring Integration - how to keep the orginal payload and use it later?

Question

I would like to keep the original payload of the original requests and ise it in a xslt-transformer or in other operation. I lose it because I use an xslt-transformer and I need just some of the elements in the transformation. So my scenario is:

1.inbound-gateway (incoming WS req) -> 2.xslt-transformer (mapping for calling an external WS) -> 3.outbound-gateway (calling the external WS) -> 4.xslt-transformer (creating response from the resp. of the external WS and the original req)

At the 4th step I don't have the original req but I'd need it as I have to put values from it to the response. How could I implement it?

Thanks, V.

<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:int="http://www.springframework.org/schema/integration" xmlns:int-ws="http://www.springframework.org/schema/integration/ws" xmlns:int-xml="http://www.springframework.org/schema/integration/xml" xmlns:util="http://www.springframework.org/schema/util" xsi:schemaLocation="http://www.springframework.org/schema/integration/ws http://www.springframework.org/schema/integration/ws/spring-integration-ws.xsd http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd                        http://www.springframework.org/schema/integration/xml http://www.springframework.org/schema/integration/xml/spring-integration-xml.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">

<bean id="authenticator" class="uk.co.virginmedia.test.Authenticator"/>
<bean id="webserviceDestinationProvider" class="uk.co.virginmedia.test.WebserviceDestinationProvider"/>
<bean id="resultToDocumentTransformer" class="org.springframework.integration.xml.transformer.ResultToDocumentTransformer"/>

<util:map id="orderNamespaceMap">
    <entry key="res" value="http://schema/ReserveAppointment/2/0" />
</util:map>

<int-ws:inbound-gateway id="ws-gateway-for-rbta" request-channel="incoming-req-channel" reply-channel=""/>

<int:channel id="incoming-req-channel"/>

<int:service-activator id="authentication" input-channel="incoming-req-channel" ref="authenticator" method="authenticate" output-channel="authenticated-channel" />

<int:channel id="authenticated-channel"/>

<int-xml:xpath-router id="servicetype-router" input-channel="authenticated-channel" evaluate-as-string="true">
    <int-xml:xpath-expression expression="//res:ReserveAppointmentRequest/res:serviceType/text()" ns-prefix="res" ns-uri="http://schema/ReserveAppointment/2/0"/>
    <int-xml:mapping value="Broadband" channel="broadband-channel"/>
    <int-xml:mapping value="FTTC+WholesaleLineRental" channel="fttc-wlr-channel"/>
</int-xml:xpath-router>

<int:channel id="broadband-channel"/>

<int-xml:xslt-transformer id="req_for_bt_xslt_transformer" input-channel="broadband-channel" output-channel="domresult_for_bt_channel" xsl-resource="classpath:/xsl/ToBTReq.xsl" result-type="StringResult"/>

<int:channel id="domresult_for_bt_channel"/>

<int:transformer input-channel="domresult_for_bt_channel" output-channel="document_for_bt_channel" expression="payload.toString()"/>

<int:channel id="document_for_bt_channel"/>

<int-ws:outbound-gateway request-channel="document_for_bt_channel" reply-channel="resp_from_bt_channel" destination-provider="webserviceDestinationProvider" id="call_bt-outbound_gateway" />

<int:channel id="resp_from_bt_channel"/>

<int-xml:xslt-transformer id="resp_for_rbta_xslt_transformer" input-channel="resp_from_bt_channel" output-channel="resp_for_rbta_channel" xsl-resource="classpath:/xsl/ToBTReq.xsl" result-type="StringResult"/>

Answer 1

Since your original message is just text you could copy it to a header field. This should work as long as you don't do anything special in between when you store and afterwards retrieve it.

So what I would try is:

<int:header-enricher input-channel="authenticated-channel" output-channel="pre-routing-channel">
   <int:header name="original-payload" expression="payload.toString()" />
</int:header-enricher>

<!-- changed input channel of router -->
<int-xml:xpath-router id="servicetype-router" input-channel="pre-routing-channel" evaluate-as-string="true">

If this is not working for you (maybe because you have to do something more special in between or the payload is too big), you still have the option to use a ClaimCheck. Which is actually exactly what you are asking for. For this you'll need a MessageStore and then just store the message payload before modifying it. So instead of the header-enricher you will call

<int:claim-check-in input-channel="authenticated-channel" output-channel="pre-routing-channel" message-store="payloadstore" />

<!-- MessageStore definition storing payload using in memory map -->
<bean id="simpleMessageStore"
    class="org.springframework.integration.store.SimpleMessageStore"/>