Merge pull request 'Fix for visible role issue' (#190) from prathabanKavin/device-mgt-core:visiblerolefix into master

Reviewed-on: community/device-mgt-core#190

components/device-mgt/io.entgra.device.mgt.core.device.mgt.api/src/main/java/io/entgra/device/mgt/core/device/mgt/api/jaxrs/service/impl/RoleManagementServiceImpl.java

@@ -126,8 +126,11 @@ public class RoleManagementServiceImpl implements RoleManagementService {
         List<String> visibleRoles;
         RoleList visibleRoleList = new RoleList();
         try {
-            metadata = DeviceMgtAPIUtils.getMetadataManagementService().retrieveMetadata(metaKey);
-            String metaValue = metadata.getMetaValue();
+            String metaValue = "{\"isUserAbleToViewAllRoles\":false}";
+            if(DeviceMgtAPIUtils.getMetadataManagementService().retrieveMetadata(metaKey) != null){
+                metadata = DeviceMgtAPIUtils.getMetadataManagementService().retrieveMetadata(metaKey);
+                metaValue = metadata.getMetaValue();
+            }
             JSONParser parser = new JSONParser();
             JSONObject jsonObject = (JSONObject) parser.parse(metaValue);
             boolean decision = (boolean) jsonObject.get(Constants.IS_USER_ABLE_TO_VIEW_ALL_ROLES);