Using CRUDService to delete all elements in a list

[vadigreg]

Hello,

I'm trying to delete all elements from a list. My YANG is like:

  container wlan-cfg-data {
    container wlan-cfg-entries {
      list wlan-cfg-entry {
        key "profile-name";

So basically I want to remove all wlan-cfg-entry from wlan-cfg-entries. I've tried this:

entries = Cisco_IOS_XE_wireless_wlan_cfg.WlanCfgData.WlanCfgEntries()
entries.yfilter = YFilter.delete
service.delete(provider, entries)

But it doesn't work. It issues a DELETE (Restconf) on /data/Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data rather than /data/Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data/wlan-cfg-entries. I know that the latter path would work instead. I tried to follow the example here http://ydk.cisco.com/py/docs/guides/crud_guide.html#deleting-a-list but it doesn't seem to delete a list, it rather deletes an element from a list.

Any help is appreciated.

Thanks,

Val

[yangorelik]

Hi Val

There are multiple errors in your script. Here is how you should do it:

# First you need to read existing configuration
cfg_data = Cisco_IOS_XE_wireless_wlan_cfg.WlanCfgData()
wlan_cfg = service.read_config(provider, cfg_data)

# Then delete all elements in the list in one operation
if len(wlan_cfg.wlan_cfg_entries.wlan_cfg_entry) > 0:
    wlan_cfg.wlan_cfg_entries.wlan_cfg_entry.yfilter = YFilter.delete
    service.update(provider, wlan_cfg)

 I suggest you to run your script with logging level INFO so you could clearly see RPCs sent and received.

[vadigreg]

Hi Yan,

thanks for your reply. This is actually failing for the same reason:

2020-06-23T11:11:38: %AETEST-ERROR:   File "/nobackup/pyats/lib/python3.6/site-packages/ydk/errors/error_handler.py", line 112, in helper
2020-06-23T11:11:38: %AETEST-ERROR:     return func(self, provider, entity, *args, **kwargs)
2020-06-23T11:11:38: %AETEST-ERROR:   File "/nobackup/pyats/lib/python3.6/site-packages/ydk/services/crud_service.py", line 53, in delete
2020-06-23T11:11:38: %AETEST-ERROR:     return _crud_update(provider, entity, self._crud.delete)
2020-06-23T11:11:38: %AETEST-ERROR:   File "/nobackup/pyats/lib/python3.6/site-packages/ydk/services/crud_service.py", line 70, in _crud_update
2020-06-23T11:11:38: %AETEST-ERROR:     return crud_call(provider, entity)
2020-06-23T11:11:38: %AETEST-ERROR:   File "/auto/pysw/cel8x/python64/3.6.10/lib/python3.6/contextlib.py", line 99, in __exit__
2020-06-23T11:11:38: %AETEST-ERROR:     self.gen.throw(type, value, traceback)
2020-06-23T11:11:38: %AETEST-ERROR:   File "/nobackup/pyats/lib/python3.6/site-packages/ydk/errors/error_handler.py", line 82, in handle_runtime_error
2020-06-23T11:11:38: %AETEST-ERROR:     _raise(_exc)
2020-06-23T11:11:38: %AETEST-ERROR:   File "/nobackup/pyats/lib/python3.6/site-packages/ydk/errors/error_handler.py", line 54, in _raise
2020-06-23T11:11:38: %AETEST-ERROR:     exec("raise exc from None")
2020-06-23T11:11:38: %AETEST-ERROR:   File "<string>", line 1, in <module>
2020-06-23T11:11:38: %AETEST-ERROR: ydk.errors.YError: invalid format string

What I want to do is to exercise the following API:

DELETE /data/Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data/wlan-cfg-entries

However what I can see from logs is:

2020-06-23T11:14:19: %YDK-INFO: Executing CRUD update operation on [Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data]
2020-06-23T11:14:19: %YDK-INFO: Performing PATCH on URL /data/Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data. Payload:
2020-06-23T11:14:19: %YDK-INFO: {
2020-06-23T11:14:19: %YDK-INFO:   "Cisco-IOS-XE-wireless-wlan-cfg:wlan-cfg-data": {
2020-06-23T11:14:19: %YDK-INFO:     "wlan-cfg-entries": {
2020-06-23T11:14:19: %YDK-INFO:       "wlan-cfg-entry": [
2020-06-23T11:14:19: %YDK-INFO:         {
2020-06-23T11:14:19: %YDK-INFO:           "@": {
2020-06-23T11:14:19: %YDK-INFO:             "ietf-netconf:operation":"delete"
2020-06-23T11:14:19: %YDK-INFO:           },
2020-06-23T11:14:19: %YDK-INFO:           "profile-name": "new_wlan",
[...]

And PATCH is not exactly what I want.

Regards,

Val

[vadigreg]

So it seems this:

entries = Cisco_IOS_XE_wireless_wlan_cfg.WlanCfgData.WlanCfgEntries()
entries.yfilter = YFilter.delete
result = service.update(restconf_provider, entries)

works well only if provider is started with XML encoding. Using JSON encoding doesn't work on IOS-XE and Cat9k device.