# Notification for leaf-list changes is not sent

**URL:** https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209
**Category:** CDB and CDB API
**Created:** [August 6, 2020, 9:16am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209 "2020-08-06T09:16:47Z")
**Posts on this page:** 11
**Page:** 1

<div class="post-metadata">

### Author: ![hzpfly](https://avatars.discourse-cdn.com/v4/letter/h/f04885/32.png) [@hzpfly](https://dmap-community.ductus.global/u/hzpfly)
#### Post date: [August 6, 2020, 9:16am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/1 "2020-08-06T09:16:47Z")

</div>

I am testing the Confd notification function.  
The YANG model is like this:

```
container container-x {
    leaf attributeQQ {
        type string;
    }
    leaf-list "conflicting-leaf-list" {
        type string;
        description
          "Holds the ns conflicting leaflist";
    }
}

```

The configuration is as below:

```
1. <data> 
2. <container-x xmlns="urn:rdns:com:oammodel:complete">
3. <conflicting-leaf-list>Hello</conflicting-leaf-list>
4. <conflicting-leaf-list>World</conflicting-leaf-list>
5. <conflicting-leaf-list>new3</conflicting-leaf-list>
6. </container-x>
7. </data>

```

First the subscription is done. Then I update the leaf-list through netconf edit-config message:

```
<edit-config><target><running/></target>
<config xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0"
xmlns:yang="urn:ietf:params:xml:ns:yang:1"
xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<container-x xmlns="urn:rdns:com:oammodel:complete"><conflicting-leaf-list>new4</conflicting-leaf-list>
</container-x>
</config>

```

The changes is successful:

```
1. <data>
2. <container-x xmlns="urn:rdns:com:oammodel:complete">
3. <conflicting-leaf-list>Hello</conflicting-leaf-list>
4. <conflicting-leaf-list>World</conflicting-leaf-list>
5. <conflicting-leaf-list>new3</conflicting-leaf-list>
6. <conflicting-leaf-list>new4</conflicting-leaf-list>
7. </container-x>
8. </data>

```

But there is no notification sent by ConfD. There is a error in log:

```
<ERR> 6-Aug-2020::10:18:43.997 confd[17]: devel-c Failed to send notification for stream DATA-CHANGE: /push-change-update/change/target: {34,
                                    [{<<"new4">>},
                                     1728446403,
                                     [252269338|1377102414]]}: The XPath /ecomplete:container-x/ecomplete:conflicting-leaf-list[.="new4"] doesn't belong to the restricted subset.

```

What is the root cause of this error? Thank you very much.

---

<div class="post-metadata">

### Author: ![mvf](https://yyz2.discourse-cdn.com/flex010/user_avatar/dmap-community.ductus.global/mvf/32/182_2.png) [@mvf](https://dmap-community.ductus.global/u/mvf)
#### Post date: [August 7, 2020, 12:58pm UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/2 "2020-08-07T12:58:37Z")

</div>

This looks weird, but you do not show how the subscription was created, in particular how the filter looks like.

---

<div class="post-metadata">

### Author: ![Fei.Du](https://avatars.discourse-cdn.com/v4/letter/f/278dde/32.png) [@Fei.Du](https://dmap-community.ductus.global/u/Fei.Du)
#### Post date: [August 10, 2020, 2:39am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/3 "2020-08-10T02:39:31Z")

</div>

Hi,

We use the simple netconf create command as below, no filter specified in the command:

```
<?xml version="1.0" encoding="UTF-8"?>
<netconf:rpc message-id="101"
      xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
    <create-subscription
        xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
                <stream>TEST-DATA-CHANGE</stream>
    </create-subscription>
</netconf:rpc>
]]>]]>
```

---

<div class="post-metadata">

### Author: ![hzpfly](https://avatars.discourse-cdn.com/v4/letter/h/f04885/32.png) [@hzpfly](https://dmap-community.ductus.global/u/hzpfly)
#### Post date: [August 11, 2020, 1:08am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/4 "2020-08-11T01:08:16Z")

</div>

Here is the configuration in confd.conf:

```
<notifications>
    <eventStreams>
        <stream>
            <name>NETCONF</name>
            <description>Netconf Stream</description>
            <replaySupport>true</replaySupport>
            <builtinReplayStore>
            <enabled>true</enabled>
            <dir>./</dir>
            <maxSize>10M</maxSize>
            <maxFiles>50</maxFiles>
            </builtinReplayStore>
        </stream>
        <stream>
            <name>TEST-DATA-CHANGE</name>
            <description>Test Netconf Stream</description>
            <replaySupport>true</replaySupport>
            <builtinReplayStore>
            <enabled>true</enabled>
            <dir>/tmp</dir>
            <maxSize>10M</maxSize>
            <maxFiles>50</maxFiles>
            </builtinReplayStore>
        </stream>
    </eventStreams>
</notifications>
```

---

<div class="post-metadata">

### Author: ![nabil](https://avatars.discourse-cdn.com/v4/letter/n/e79b87/32.png) [@nabil](https://dmap-community.ductus.global/u/nabil)
#### Post date: [August 11, 2020, 4:25am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/5 "2020-08-11T04:25:30Z")

</div>

> [@hzpfly](#):
>
> /push-change-update/change/target

What is this tagpath?  
Can you share the YANG module snippet for the notification?  
I am wondering if you have some restriction in the notification model, or the model expects a different format?

---

<div class="post-metadata">

### Author: ![hzpfly](https://avatars.discourse-cdn.com/v4/letter/h/f04885/32.png) [@hzpfly](https://dmap-community.ductus.global/u/hzpfly)
#### Post date: [August 12, 2020, 1:26am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/6 "2020-08-12T01:26:31Z")

</div>

Is the tagpath the XPath printed in the error log: /ecomplete:container-x/ecomplete:conflicting-leaf-list[.=“new4”]?

YANG module:

```
notification push-change-update {
    description "Generated when the server detects that the
        <running> datastore or state data has changed.
        The notification summarizes the changes. 

        Sent on the TEST-DATA-CHANGE stream,
        but not on the NETCONF stream.";

    /* As there might not be any data specific access control on
    * push-change-update notifications, a subscriber may receive information
    * about all data in the ME. This may include security sensitive data.
    * push-change-update notifications will only be sent to
    * subscribers for whom an explicit permit rule is defined. */
    nacm:default-deny-all;

    leaf sequence-number {
        type uint64 ;
    }

    uses ncn:changed-by-parms;

    list change {
        description "A change entry SHALL be present for each distinct
            configuration or state change that the server has detected.";

        leaf target {
            type instance-identifier;
            mandatory true;
            description "Top-most data node within
                the datastore associated with the change.";
        }

        leaf operation {
            type enumeration {
                enum create {
                  value 0;
                }
                enum delete {
                  value 1;
                }
                enum insert {
                  value 2;

                }
                enum "merge" {
                    value 3;
                }
                enum move {
                  value 4;
                }
                /* replace not used as containers/list entries are instead
                 * deleted and re-created while for other data nodes the
                 * merge operation is used.
                 *
                 * remove not used as in this context it means the same
                 * as delete */
            }
            mandatory true;
            description "Type of edit operation / change detected.";
        }

        leaf point {
            when "(../operation = 'insert' or ../operation = 'move')"
                    + "and (../where = 'before' or ../where = 'after')" {
                description
                    "This leaf only applies for 'insert' or 'move'
                     operations, before or after an existing entry.";
            }
            type instance-identifier;
            description
                "The path for the data node that is being
                used as the insertion point or move point for the
                target of this 'change' entry.";
    }
        anyxml value {
            when "../operation = 'create' "
                + "or ../operation = 'merge' "
                + "or ../operation = 'insert'";
        }
    }
}
```

---

<div class="post-metadata">

### Author: ![hzpfly](https://avatars.discourse-cdn.com/v4/letter/h/f04885/32.png) [@hzpfly](https://dmap-community.ductus.global/u/hzpfly)
#### Post date: [August 13, 2020, 7:02am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/7 "2020-08-13T07:02:40Z")

</div>

Update on this issue:  
We found a solution to send notification for this case:  
change the 4th argument flags in function maapi\_diff\_iterate from 0 to ITER\_WANT\_LEAF\_LIST\_AS\_LEAF which is deprecated.

---

<div class="post-metadata">

### Author: ![nabil](https://avatars.discourse-cdn.com/v4/letter/n/e79b87/32.png) [@nabil](https://dmap-community.ductus.global/u/nabil)
#### Post date: [August 13, 2020, 7:55pm UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/8 "2020-08-13T19:55:33Z")

</div>

I see. I think you need to remove ITER\_WANT\_LEAF\_LIST\_AS\_LEAF and fix the issue of processing this leaf as a leaf-list (C\_LIST type).  
Your code that sends the notification needs to populate this field the right way.

Here is a snippet in c that can give you an idea:

> confd\_value\_t arr[5];  
> confd\_value\_t v;
> 
> for (j=0; j\<5; j++) CONFD\_SET\_INT32(&arr[j], j);
> 
> CONFD\_SET\_LIST(&v, &arr[0], 5);  
> CONFD\_SET\_TAG\_VALUE(&vals[i], notif\_extra\_id, &v);i++;

---

<div class="post-metadata">

### Author: ![Zhenhua](https://avatars.discourse-cdn.com/v4/letter/z/e9bcb4/32.png) [@Zhenhua](https://dmap-community.ductus.global/u/Zhenhua)
#### Post date: [August 19, 2020, 4:10am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/9 "2020-08-19T04:10:00Z")

</div>

**Notification module:**

```
notification push-change-update {
...
    list change {
        description "A change entry SHALL be present for each distinct
            configuration or state change that the server has detected.";

        leaf target {
            type instance-identifier;
            mandatory true;
            description "Top-most data node within
                the datastore associated with the change.";
        }
...
}

```

**Error Logs**

```
<ERR> 6-Aug-2020::10:18:43.997 confd[17]: devel-c Failed to send notification for stream DATA-CHANGE: /push-change-update/change/target: {34,
                                    [{<<"new4">>},
                                     1728446403,
                                     [252269338|1377102414]]}: The XPath /ecomplete:container-x/ecomplete:conflicting-leaf-list[.="new4"] doesn't belong to the restricted subset.

```

**why confd reports the above error?**

As you can see that /ecomplete:container-x/ecomplete:conflicting-leaf-list[.=“new4”] is a valid instance-identifier. Refer to rfc7950 ([https://tools.ietf.org/html/rfc7950#section-9.13.4](https://tools.ietf.org/html/rfc7950#section-9.13.4)). why confd reports the error?

**ITER\_WANT\_LEAF\_LIST\_AS\_LEAF**

if maapi\_diff\_iterate doesn’t use ITER\_WANT\_LEAF\_LIST\_AS\_LEAF parameter, confd will generate the diff by go through every leaf of the leaf-list, and the xpath of the diff will be /ecomplete:container-x/ecomplete:conflicting-leaf-list[.=“new4”]. Am i right?

**Build notification message**

```
confd_hkeypath_t *thekp;
int res = maapi_xpath2kpath(_maapiSocket, kp.c_str(), &thekp);
CONFD_SET_TAG_OBJECTREF(&_valueArray[_i],_change_target->tag, thekp); _i++;

```

**send out notification message**

```
confd_notification_send(_live_ctx,&eventTime,valueArray,numberOfEntries);

```

Then confd reports the above error. is It a confd issue?

---

<div class="post-metadata">

### Author: ![nabil](https://avatars.discourse-cdn.com/v4/letter/n/e79b87/32.png) [@nabil](https://dmap-community.ductus.global/u/nabil)
#### Post date: [August 25, 2020, 7:18am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/10 "2020-08-25T07:18:23Z")

</div>

I think we are talking about two issues. I thought the issue was only around the “leaf-list as leaf”.  
Regarding the maapi\_diff\_iterate, I think you can test and find out what ConfD diffs over, easily. That should answer your question. The diff will be similar to lists.

Regarding the notification, I think something is wrong here. You are right that the XPath expression is a valid value for an instance-identifier type, based on the YANG RFC.  
But since the behavior of the leaf-list implementation is changed, I don’t know if this is why the path is restricted.

For sure, if you omit ‘[.=“new4”]’, it should work.

I think ConfD, in this case, looks at the XPath and thinks “leaf-list = leaf”, then the extra predicate shouldn’t be present. This explains the error message you get. One thing you can try is to remove the backward compatibility settings and try.

But I highly doubt it would work, so this may be a bug in ConfD. I will double check internally.

Thanks!  
Nabil

---

<div class="post-metadata">

### Author: ![Zhenhua](https://avatars.discourse-cdn.com/v4/letter/z/e9bcb4/32.png) [@Zhenhua](https://dmap-community.ductus.global/u/Zhenhua)
#### Post date: [September 18, 2020, 5:13am UTC](https://dmap-community.ductus.global/t/notification-for-leaf-list-changes-is-not-sent/3209/11 "2020-09-18T05:13:12Z")

</div>

> [@nabil](#):
>
> may

Hi Nabil

Thanks for your answer!  
We are trying to send out notifications when configuration changes, which includes the leaf-list changes. The bug in confd blocks our tasks.

please let us know if some new version confd can fix the bug.

BRs/Zhenhua