【发布时间】：2013-11-07 21:21:54
【问题描述】：
在我的 WSO2 ESB 4.7.0 中，我已经配置了这个代理：
<proxy xmlns="http://ws.apache.org/ns/synapse" name="SendingByJmsAddressProxy"
transports="https,http"
statistics="disable"
trace="disable"
startOnLoad="true">
<target>
<inSequence>
<send>
<endpoint>
<address uri="http://localhost:8080/RestService/rest/servizio"/>
</endpoint>
</send>
</inSequence>
<outSequence>
<log>
<property name="codice" expression="//codice"/>
</log>
<log level="full"/>
<switch source="//codice">
<case regex="asd">
<send/>
</case>
<case regex="0">
<log>
<property name="codice" value="check1"/>
</log>
<send/>
<payloadFactory media-type="xml">
<format>
<code>$1</code>
</format>
<args>
<arg xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope" evaluator="xml"
expression="//codice"/>
</args>
</payloadFactory>
<property name="messageType" value="application/xml"/>
<log level="full"/>
<send>
<endpoint>
<address uri="jms:/testQueue?transport.jms.ConnectionFactoryJNDIName=QueueConnectionFactory&java.naming.factory.initial=org.wso2.andes.jndi.PropertiesFileInitialContextFactory&java.naming.provider.url=repository/conf/jndi.properties&transport.jms.DestinationType=queue"/>
</endpoint>
</send>
</case>
</switch>
</outSequence>
</target>
<description/>
</proxy>
在 inSequence 中，我将客户端的请求转发给 Rest Service，其响应是一个如下所示的 json 字符串：
{
"codice":"0",
"messaggio":"Operazione effettuata 18:12",
"path":"\/path\/1AASSCOGNOME_NOME.111.2231\/",
"documenti":[{
"idAggregatoContenitore":"3508",
"idDocumento":"016601",
"idVersione":"17010",
"numVersione":"1",
"tipoDocumento":"Documento",
"autore":"sysadmin",
"titolo":"prova1",
"fileName":"FStandard.xml",
"checkedOut":"false",
"idDocumentoPadre":"",
"flagAllegati":"false",
"flagDaProtocollare":"true",
"dataCreazione":"11\/02\/2013 19:05",
"dataChekin":"11\/02\/2013 19:05",
"mimeType":"text\/xml",
"empty":"false",
"data":"1660100000",
"cache":"false",
"tipo":"D",
"nome":"prova1",
"keyData":"16601",
"keyNome":"prova1",
"keyNumero":"",
"keyTipo":"D",
"fileExtension":"path\/xml_file.png",
"evidenza":"false",
"originalDocumentoPadreId":"",
"originalDocumentoId":"016601",
"originalAggregatoContenitoreId":"3508"
},
{
"idAggregatoContenitore":"3508",
"idDocumento":"016602",
"idVersione":"17011",
"numVersione":"1",
"tipoDocumento":"Documento",
"autore":"sysadmin",
"titolo":"123456789",
"fileName":"HTTP Proxy Server.jmx",
"checkedOut":"false",
"idDocumentoPadre":"",
"flagAllegati":"false",
"flagDaProtocollare":"true",
"dataCreazione":"11\/02\/2013 19:19",
"dataChekin":"11\/02\/2013 19:19",
"mimeType":"application\/octet-stream",
"empty":"false",
"data":"1660200000",
"cache":"false",
"tipo":"D",
"nome":"123456789",
"keyData":"16602",
"keyNome":"123456789",
"keyNumero":"",
"keyTipo":"D",
"fileExtension":"path\/Documento.png",
"evidenza":"false",
"originalDocumentoPadreId":"",
"originalDocumentoId":"016602",
"originalAggregatoContenitoreId":"3508"
}],
"data":"350800000",
"tipoAggregatoEnum":"R",
"statoEnum":"aperto",
"keyData":"1360602720000",
"keyNome":"1aasscognome_nome.111.2231",
"nomeAggregatoNoNumero":"1AASSCOGNOME_NOME.111.2231",
"keyNumero":"1AASSCOGNOME_NOME.111.2231",
"keyTipo":"R",
"originalAggregatoId":"3508",
"originalAggregatoPadre":"3108"
}
作为标准行为，ESB 将传入的 json 消息转换为 xml 格式的消息。 现在在我想要的 outSequence 中：
1) 将 RestService 响应发送回客户端：由中介
2）然后我想构建一个 xml 消息，从消息负载中提取一些元素，然后通过 jms 协议将其发送到其他地方。
除了 PayloadFactory 中介之外，代理都可以正常工作。实际上，由 Payload Factory 中介构建的消息的主体是空的：
<soapenv:Envelope xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">
<Body>
<code xmlns="http://ws.apache.org/ns/synapse"/>
</Body>
</soapenv:Envelope>
谁能告诉我为什么指定的 arg 标签为空（xpath 表达式似乎是正确的）？怎么了？ 谢谢
【问题讨论】：
标签： wso2 wso2esb payload mediator