Proxy a RESTful service using SOAP with WSO2 ESB - rest

Question

We want to proxy a RESTful web service with SOAP.
The REST service uses the GET method and accepts inputs via query parameters. It produces a resource of type application/csv.
Does WSO2 ESB/Synapse support such a scenario, and is there an example available?
Example Request
SOAP Proxy Request:
<request>
<fromDate>2012-01-01</fromDate>
<toDate>2012-12-31</toDate>
</request>
REST Endpoint Request:
http://localhost/person?fromDate=2012-01-01&toDate=2012-12-31
Example Response
REST Endpoint Response
"Name","Age","Sex"
"Geoff","22","Male"
SOAP Proxy Response
<person>
<name>Geoff</name>
<age>22</age>
<sex>Male</sex>
<person>
Many thanks.

Answer 1

If I understand you correctly, you want to expose a REST service as a SOAP service, so that SOAP clients can access your REST service through the ESB?
If that is the case, it is possible :) You should check out sample 152 from these: http://docs.wso2.org/wiki/display/ESB451/Proxy+Service+Samples
It'll explain how you take a SOAP request and pass it to a REST backend and then transform the REST response into a SOAP response.
EDIT: Here's a sample configuration on how to do what you asked in the comments, hopefully it will get you started :)
<proxy xmlns="http://ws.apache.org/ns/synapse" name="RESTProxy" transports="https,http" statistics="disable" trace="disable" startOnLoad="true">
<target>
<inSequence>
<!-- We set the HTTP Method we want to use to make the REST request here -->
<property name="HTTP_METHOD" value="GET" scope="axis2"/>
<!-- This is where the magic happens, for what you want i.e. mapping SOAP "params" to REST query param's -->
<property name="messageType" value="application/x-www-form-urlencoded" scope="axis2"/>
<send>
<endpoint>
<!-- This is the RESTful URL we are going to query, like the one in the ESB example 152 -->
<address uri="http://localhost/person" />
</endpoint>
</send>
</inSequence>
<outSequence>
<log level="full"/>
<property name="messageType" value="text/xml" scope="axis2"/>
<send/>
</outSequence>
</target>
<description></description>
</proxy>
Then the SOAP request you make to the ESB should be something like:
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
<soapenv:Header/>
<soapenv:Body>
<person>
<fromDate>2012-01-01</fromDate>
<toDate>2012-12-31</toDate>
</person>
</soapenv:Body>
</soapenv:Envelope>
Hope that helps :)

Answer 2

Hope This will be very helpful you to understand of SOAP Client and REST Service communication
http://docs.wso2.org/display/ESB460/Using+REST+with+a+Proxy+Service#UsingRESTwithaProxyService-SOAPClientandRESTService

Answer 3

You can use class mediator to extract the SOAP parameters using XPATH. Than build the REST URL and send it back to IN sequence flow.

Answer 4

1. you need to get the value from SOAP PROXY
2. you need to store it in a local variable
3. you need to pass the value to the REST SERVICE using Query Parameters
4. you need to format the response from REST Service to an SOAP Format
The SOAP Request will be,
<request>
<fromDate>2012-01-01</fromDate>
<toDate>2012-12-31</toDate>
</request>
You can store the value from SOAP PROXY Request as,
<proxy xmlns="http://ws.apache.org/ns/synapse" name="RESTProxy" transports="https,http" statistics="disable" trace="disable" startOnLoad="true><target>
<inSequence>
<property name="fromDate" expression="//fromDate" scope="default" type="STRING"/>
<property name="toDate" expression="//toDate" scope="default" type="STRING"/>
Then you can pass the values to the REST Service by,
<send>
<endpoint>
<http method="GET" uri-template="http://localhost/person?fromDate=={get-property('fromDate')}&toDate={get-property('toDate')}"/>
</endpoint>
</send>
</inSequence>
Then You can Format the Response using PayloadFactory mediator,
<outSequence>
<payloadFactory media-type="xml">
<format>
<person>
<Name>$1</Name>
<Age>$2</Age>
<Sex>$3</Sex>
</person>
</format>
<args>
<arg evaluator="json" expression="$.Name"/>
<arg evaluator="json" expression="$.Age"/>
<arg evaluator="json" expression="$.Sex"/>
</args>
</payloadFactory>
<send/>
</outSequence>
</target>
<description/>
</proxy>
So the Response of Proxy will be,
<person>
<name>Geoff</name>
<age>22</age>
<sex>Male</sex>
<person>