In wso2 esb i can send but i am not able to listen to websocket

Question

In wso2 ESB, I am able to send data to WebSocket but I am not able to receive data. I tried this with rest api of wso2 esb.

<?xml version="1.0" encoding="UTF-8"?>
<api context="/test" name="test" xmlns="http://ws.apache.org/ns/synapse">
    <resource methods="POST">
        <inSequence>
            <property name="OUT_ONLY" scope="default" type="STRING" value="true"/>
            <property name="FORCE_SC_ACCEPTED" scope="axis2" type="STRING" value="true"/>
            <log level="full">
                <property name="message" value="********************************************input**********************"/>
            </log>
            <send>
                <endpoint>
                    <http method="post" uri-template="ws://localhost:8080/websocket/server"/>
                </endpoint>
            </send>
        </inSequence>
        <outSequence>

            <send/>
        </outSequence>
        <faultSequence/>
    </resource>
</api>

outsequence:

<?xml version="1.0" encoding="UTF-8"?>
<sequence name="outflowDispatchSeq" trace="disable" xmlns="http://ws.apache.org/ns/synapse">
    <log level="full">
        <property name="message" value="************************************************"/>
    </log>
</sequence>

with the above API, I am able to send data to the server as shown in below image.

Http request from postman.

But as shown in below image of the console, the response which i am getting is empty as no body present.

If I use proxy service with content-type mentioned as in esb documentation(link) in websocket server i am getting exception

<?xml version="1.0" encoding="UTF-8"?>
<sequence name="dispatchSeq" trace="disable" xmlns="http://ws.apache.org/ns/synapse">
 <property name="OUT_ONLY" value="true"/>
        <property name="FORCE_SC_ACCEPTED" scope="axis2" type="STRING" value="true"/>
        <property name="websocket.accept.contenType" scope="axis2" value="text/plain"/>
        <send>
            <endpoint>
                <address uri="ws://localhost:8080/websocket/server"/>
            </endpoint>
        </send>
</sequence>

axis2.xml websocket configuration is:

<transportSender name="ws" class="org.wso2.carbon.websocket.transport.WebsocketTransportSender">
        <parameter name="ws.outflow.dispatch.sequence" locked="false">outflowDispatchSeq</parameter>
        <parameter name="ws.outflow.dispatch.fault.sequence" locked="false">outflowFaultSeq</parameter>       
    </transportSender>

So how to send and receive the data from websocket