In the process of creating VF-Module flow,  when mso calls SDNC sends an error (stated as  "BAD REQUEST") in response. There are two parts in this issue.

First issue, is the url form in MSO was wrong (/restconf/operations/NBNC-API was form instead of /restconf/operations/VNF-API) and also second, the request body is not correctly formed. This is an issue because of which the call was erroneous.

Workaround we tried (in RED)

Work around for Issue#1: To resolve this, we did following changes in /etc/mso/config.d/mso.sdnc.properties

_org.openecomp.mso.adapters.sdnc.sdncurl1=http://10.247.59.36:8282/restconf/operations/L3SDN-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl2=http://10.247.59.36:8282/restconf/config/L3SDN-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl3=http://10.247.59.36:8282/restconf/operations/Firewall-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl4=http://10.247.59.36:8282/restconf/config_

_org.openecomp.mso.adapters.sdnc.sdncurl5=http://localhost/_

_org.openecomp.mso.adapters.sdnc.sdncurl6=http://10.247.59.36:8282/restconf/operations/VNF-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl7=http://10.247.59.36:8282/restconf/operations/NBNC-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl8=http://10.247.59.36:8282/restconf/operations/NORTHBOUND-API:service-topology-operation_

_org.openecomp.mso.adapters.sdnc.sdncurl9=http://10.247.59.36:8282/restconf/operations/GENERIC-RESOURCE-API:_

_org.openecomp.mso.adapters.sdnc.sdncurl10=http://10.247.59.36:8282/restconf/operations/VNFTOPOLOGYAIC-API:_ 

Work around for issue#2:

The request form for the API (/restconf/operations/VNF-API) was wrong. We corrected it as below

<?xml version="1.0" encoding="UTF-8"?>

<input xmlns="org:openecomp:sdnctl:vnf">

<sdnc-request-header>

                        <svc-request-id>d29dc981-d25c-46e1-8680-d72a4921c48e</svc-request-id>

                        <svc-action>assign</svc-action>

                        <svc-notification-url>http://mso:8080/adapters/rest/SDNCNotify</svc-notification-url>

            </sdnc-request-header>

            <request-information >

                        <request-id>d29dc981-d25c-46e1-8680-d72a4921c48e</request-id>

                        <request-action>VNFActivateRequest</request-action>

                        <source>VID</source>

                        <notification-url/>

            </request-information>

            <service-information >

                        <service-id>Demo1Service</service-id>

                        <service-type>Demo1Service</service-type>

                        <service-instance-id>fce81e3f-cc25-4aa5-9b87-3f7194c7b7cd</service-instance-id>

                        <subscriber-name>notsurewecare</subscriber-name>

</service-information>

            <vnf-request-information >

                        <vnf-id>2bba3396-1b2e-4ce8-bc0c-237a43dfb263</vnf-id>

                        <vnf-type>83d3240339204dd0A207..base_vfw..module-0</vnf-type>

                        <vnf-name>deplovf</vnf-name>

                        <generic-vnf-id>951851fb-d1b8-4d02-9184-0ccc7ab558ee</generic-vnf-id>

                        <generic-vnf-name>deplovnf</generic-vnf-name>

                        <generic-vnf-type>b5df3b9a-c842-4867-b0b4/83d32403-3920-4dd0-a207 0</generic-vnf-type>

                        <aic-cloud-region>RegionOne</aic-cloud-region>

                        <tenant>2d010eb3effb4cb3be93bc632469600a</tenant>

                        <model-customization-uuid>076ea335-696e-447f-9151-de98e738ac8b</model-customization-uuid>

                        <use-preload>N</use-preload>

            </vnf-request-information>

</input> 

(model-customization-uuid was wrongly named as modelCustomizationUuid and value for it was null) we populated value from AAI get generic VNF REST API.