YDK5.5 can not create a top entity as a list

[xulleon]

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In YDK 5.5, if a module has a top entity as a list. Currently there is no way for YDK to generate a list entity. If it is not a top entity, I used to gnerate the entity and then by refer to its parent, which is the list entity. However, since the entity is at top, it dose not have a parent. Therefore the usual way to refer it parent as list does not work.

Expected Behavior

Take BGP neighbor as an example. after a neighbor instance is created as nbr. then its parent will be the neighbor list. nbr.parent.append(nbr)

Current Behavior

For Cisco-ios-xr-vrf-cfg, the top entity is Vrf, after it was created, i.e. vrf. vrf has not parent as it is on the top level. therefore, there is no way to refer its parent as the vrf_list.

Steps to Reproduce

find a module, which has a top entity as a list. simply generate the top entity, then dir the entity, you will find parent is not in the list.

Your Script

Logs

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System Information

[ygorelik]

Reproduced the issue in ydk-0.8.1 with ydktest model bundle, which defines top-level list node oc_pattern/oc-a.
Test to run:

    def test_top_list(self):
        from ydk.models.ydktest import oc_pattern
        obj_A = oc_pattern.OcA()
        obj_A.a = 'Hello'
        obj_A.b.b = 'Hello'
        
        obj_B = oc_pattern.OcA()
        obj_B.a = 'GoodBye'
        obj_B.b.b = 'GoodBye'

        self.crud.create(self.ncc, [obj_A, obj_B])
        
        obj_f = oc_pattern.OcA()
        read = self.crud.read(self.ncc, obj_f)
        print_entity(read, self.root_schema)

The test produced the following results:

2019-03-09 11:21:56,787 - ydk - INFO - Executing CRUD create operation on [oc-pattern:oc-A[a='Hello'], oc-pattern:oc-A[a='GoodBye']]
2019-03-09 11:21:56,787 - ydk - INFO - Executing 'edit-config' RPC on [oc-pattern:oc-A[a='Hello'], oc-pattern:oc-A[a='GoodBye']]
2019-03-09 11:21:56,795 - ydk - INFO - ============= Generated RPC to send to device =============
<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><edit-config xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <target>
    <candidate/>
  </target>
  <config><oc-A xmlns="http://cisco.com/ns/yang/oc-pattern" xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0" nc:operation="merge">
  <a>Hello</a>
  <B>
    <b>Hello</b>
  </B>
</oc-A>
<oc-A xmlns="http://cisco.com/ns/yang/oc-pattern" xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0" nc:operation="merge">
  <a>GoodBye</a>
  <B>
    <b>GoodBye</b>
  </B>
</oc-A>
</config>
</edit-config>
</rpc>

2019-03-09 11:21:56,814 - ydk - INFO - ============= Reply RPC received from device =============
<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="4">
  <ok/>
</rpc-reply>

2019-03-09 11:21:56,815 - ydk - INFO - Executing 'commit' RPC
2019-03-09 11:21:56,815 - ydk - INFO - ============= Generated RPC to send to device =============
<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><commit xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"/>
</rpc>

2019-03-09 11:21:56,849 - ydk - INFO - ============= Reply RPC received from device =============
<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="5">
  <ok/>
</rpc-reply>

2019-03-09 11:21:56,849 - ydk - INFO - Operation succeeded
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_encoder.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_validator.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_validator.py (will have no effect)
Error removing breakpoint: Breakpoint id not found: /usr/local/lib/python2.7/dist-packages/ydk/types/py_types.py id: 14. Available ids: [2, 12]

pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_provider_plugin.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_encoder.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_validator.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_encoder.py (will have no effect)
pydev debugger: warning: trying to add breakpoint to file that does not exist: /usr/local/lib/python2.7/dist-packages/ydk/providers/_validator.py (will have no effect)
2019-03-09 11:22:14,866 - ydk - INFO - Executing CRUD read operation on [oc-pattern:oc-A[a='None']]
2019-03-09 11:22:14,866 - ydk - INFO - Executing 'get' RPC on [oc-pattern:oc-A[a='None']]
2019-03-09 11:22:14,869 - ydk - INFO - ============= Generated RPC to send to device =============
<rpc xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><get xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <filter><oc-A xmlns="http://cisco.com/ns/yang/oc-pattern"/></filter>
</get>
</rpc>

2019-03-09 11:22:14,879 - ydk - INFO - ============= Reply RPC received from device =============
<?xml version="1.0" encoding="UTF-8"?>
<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="6">
  <data>
    <oc-A xmlns="http://cisco.com/ns/yang/oc-pattern">
      <a>GoodBye</a>
      <B>
        <b>GoodBye</b>
      </B>
    </oc-A>
    <oc-A xmlns="http://cisco.com/ns/yang/oc-pattern">
      <a>Hello</a>
      <B>
        <b>Hello</b>
      </B>
    </oc-A>
  </data>
</rpc-reply>


=====>  Printing DataNode: '/oc-pattern:oc-A[a='GoodBye']'
ok

----------------------------------------------------------------------
Ran 1 test in 99.960s

OK
<oc-A>
  <a>GoodBye</a>
  <B>
    <b>GoodBye</b>
  </B>
</oc-A>

2019-03-09 11:23:36,510 - ydk - INFO - Disconnected from device

Note, that YDK allowed create the top-level list with multiple entries and Netconf worked perfectly well. But at the end the YDK failed decode multiple list elements and returned single entry.