Unable to respond with customized error for edit-config

[marchest]

Describe the bug
Unable to respond with customized error from netconf server since Lighty overrides our custom error. However , I can see the following logs in lighty which seems correct but it's responding different than its logging.

2025-07-01 10:56:51 WARN  [NetconfDeviceCommunicator] (odl-netconf-client-2) [{}] RemoteDeviceId[name=1, address=host.docker.internal/172.17.0.1:2022]: Error reply from remote device, request: <rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="m-50">
    <edit-config>
        <target>
            <candidate/>
        </target>
        <error-option>rollback-on-error</error-option>
        <config>
            <dhcp-kea xmlns="http://nsp-dhcp.siemens.com/ns/nsp-dhcp">
                <subnetscon>
                    <subnets xmlns:op="urn:ietf:params:xml:ns:netconf:base:1.0" op:operation="create">
                        <uuid>39b29f21-de8c-4fa8-9fd7-6951607128c9</uuid>
                        <net>192.168.28.0/24</net>
                    </subnets>
                </subnetscon>
            </dhcp-kea>
        </config>
    </edit-config>
</rpc>
, response: <rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="m-50">
    <rpc-error>
        <error-type>application</error-type>
        <error-tag>operation-failed</error-tag>
        <error-severity>error</error-severity>
        <error-app-tag>data-not-unique</error-app-tag>
       <error-message xml:lang="en">&lt;&lt;&lt;labelSubnetworkDataNotUnique&gt;&gt;&gt;</error-message>
        <error-info xmlns:dhcpd-kea="http://nsp-dhcp.siemens.com/ns/nsp-dhcp" xmlns:yang="urn:ietf:params:xml:ns:yang:1">
            <yang:non-unique>/dhcpd-kea:dhcp-kea/dhcpd-kea:subnetscon/dhcpd-kea:subnets[dhcpd-kea:uuid='39b29f21-de8c-4fa8-9fd7-6951607128c9']/dhcpd-kea:net</yang:non-unique>
            <yang:non-unique>/dhcpd-kea:dhcp-kea/dhcpd-kea:subnetscon/dhcpd-kea:subnets[dhcpd-kea:uuid='87794c3c-4e8e-4ab8-8732-3255fa0a1401']/dhcpd-kea:net</yang:non-unique>
        </error-info>
    </rpc-error>
</rpc-reply>

2025-07-01 10:56:51 WARN  [NetconfRpcFutureCallback] (odl-netconf-client-2) [{}] RemoteDeviceId[name=1, address=host.docker.internal/172.17.0.1:2022]:
 Edit candidate invoked unsuccessfully: [RpcError [message=<<<labelSubnetworkDataNotUnique>>>, severity=ERROR, errorType=APPLICATION, tag=operation-failed, 
 applicationTag=null, info=<yang:non-unique>/dhcpd-kea:dhcp-kea/dhcpd-kea:subnetscon/dhcpd-kea:subnets[dhcpd-kea:uuid='87794c3c-4e8e-4ab8-8732-3255fa0a1401']/dhcpd-kea:net</yang:non-unique>, cause=null]]

HTTP 500 Response

Branch
lighty.io branch [20.3.0 release or 21.2.0]

To Reproduce
Steps to reproduce the behavior:

1. git checkout lighty- 20.3.0
2. Use any yang file and try to return custom error for the edit config.

Expected behavior
We would like to respond edit-config with a customized error due to invalid input but with the 20.3.0 release lighty overriding our response. We were using 17.3.0 version but due to EOL of that version we upgraded to 20.3.0. We were getting following response with the 17.3.0 which was fine.

{
  "errors": {
    "error": [
      {
        "error-tag": "operation-failed",
        "error-info": "<bad-element>host-specific-file-op</bad-element>",
        "error-message": "{\"status\" : {\"code\": -4, \"message\": \"<<<labelSubnetworkDataNotUnique>>>Input is wrong\"}}",
        "error-type": "application"
      }
    ]
  }
}

Environment:

• OS: [ubuntu 24.04]
• Java Version [java 17]

Thanks.

[marchest]

I couldn't observe same state with the main branch, It's working fine , I can see the custom errors. @ihrasko . Are there any plan to announce new release ?