ERP Operation not found error in WSO2EI DSS - wso2-data-services-server

Question

I have created a REST - data service in WSO2EI an tried accessing through postman client tool, but I am getting this error.
End Point: http://LAPTOP-T4F1HOAM:8280/services/getStudRecNo?user_id=test8
The endpoint reference (EPR) for the Operation not found is /services/getStudRecNo?user_id=test8 and the WSA Action = null. If this EPR was previously reachable, please contact the server administrator.
Can anyone please help.
Thanks
dss code.
<data name="getStudRecNo" transports="http https local">
<description>get student unique id</description>
<config enableOData="false" id="mySchoolDB">
<property name="driverClassName">org.postgresql.Driver</property>
<property name="url">jdbc:postgresql://localhost:5432/mySchool</property>
<property name="username">admin</property>
<property name="password">admin</property>
</config>
<query id="GetStudentRecordNo" useConfig="mySchoolDB">
<sql>SELECT getstudentid FROM getstudentid(?)</sql>
<result outputType="json">{"entries": {"entry": [ { "getstudentid": "$getstudentid"} ]}}</result>
<param defaultValue="TEST" name="user_id" sqlType="STRING"/>
</query>
<operation name="getsrno">
<call-query href="GetStudentRecordNo">
<with-param name="user_id" query-param="user_id"/>
</call-query>
</operation>
<resource method="GET" path="getsrno">
<call-query href="GetStudentRecordNo">
<with-param name="user_id" query-param="user_id"/>
</call-query>
</resource>
</data>

Answer 1

You have to append the resource path ("getsrno" in your case) to the URL. Then the URL would look like,
http://LAPTOP-T4F1HOAM:8280/services/getStudRecNo/getsrno?user_id=test8
Further, since the resource's HTTP method is GET, the request should also be a GET request.