Internet DRAFT - draft-ietf-netconf-yang-notifications-versioning
draft-ietf-netconf-yang-notifications-versioning
Network Working Group T. Graf
Internet-Draft Swisscom
Intended status: Standards Track B. Claise
Expires: 22 April 2024 Huawei
A. Huang Feng
INSA-Lyon
20 October 2023
Support of Versioning in YANG Notifications Subscription
draft-ietf-netconf-yang-notifications-versioning-03
Abstract
This document extends the YANG notifications subscription mechanism
to specify the YANG module semantic version at the subscription.
Then, a new extension with the revision and the semantic version of
the YANG push subscription state change notification is proposed.
Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 22 April 2024.
Copyright Notice
Copyright (c) 2023 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Extend the Datastore Selection . . . . . . . . . . . . . . . 3
3. Extend the Subscription State Change Notifications . . . . . 6
4. The "ietf-yang-push-revision" Module . . . . . . . . . . . . 7
4.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 8
4.2. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 19
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
5.1. IETF XML Registry . . . . . . . . . . . . . . . . . . . . 25
5.2. YANG Module Name . . . . . . . . . . . . . . . . . . . . 25
6. Operational Considerations . . . . . . . . . . . . . . . . . 25
7. Security Considerations . . . . . . . . . . . . . . . . . . . 26
8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 26
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
9.1. Normative References . . . . . . . . . . . . . . . . . . 26
9.2. Informative References . . . . . . . . . . . . . . . . . 27
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 28
1. Introduction
In order to process the newly received YANG push notification
messages described in section 3.7 of [RFC8641] without querying the
Publisher IETF-YANG-LIBRARY each time to understand whether the YANG
module(s) semantic has changed at the YANG push receiver, a semantic
reference to the YANG module and the XPath or subtree is needed to
determine the data types for each field and which part of the YANG
module the metrics are expose from.
This specification applies to the YANG push configured subscriptions
defined in Section 2.5 of [RFC8639], where a publisher is configured
to stream notification out of band, as opposed to dynamic
subscriptions defined in Section 2.4 of [RFC8639], where the
subscriber can initiate and modify the subscription dynamically in-
band. In the latter case, the subscriber knows already all the
subscriber YANG-related information, which it has to know in order to
configure the subscription.
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This semantic reference is available when the subscription is
established as described in Section 3.6 of [RFC8641] and being
streamed from the publisher to receiver with the subscription state
change notifications described in Section 2.7 of [RFC8639] where for
each subscription a locally unique subscription ID described in
Section 4.3.2 of [RFC8641] is being issued and streamed as metadata
with the notification message in the YANG push message header.
The semantics can change between different YANG module revisions.
The YANG module version statement is specified in Section 7.1.2 of
[RFC6020] and states that the newer revision needs to be backward
compatible to the previous revision. Section 3.1 of
[I-D.ietf-netmod-yang-module-versioning] specifies that newer
semantic versions introduced in [I-D.ietf-netmod-yang-semver] MAY not
be backward compatible to the previous version when indicated with
non-backwards-compatible keyword.
The YANG notifications subscription mechanism defined in [RFC8641]
does not allow to specify the YANG module revision. When a network
node is upgraded, the subscribed YANG module revision MAY have
updated and might, consequently, break the data processing pipeline
since the YANG push receiver may not be aware of this change.
This documents extends the current YANG notifications subscription
mechanism to allow to subscribe to a specific revision or latest YANG
module semantic version to which the YANG module version needs to be
backward compatible to. The subscription state change "subscription-
started" and "subscription-modified" notification messages are also
extended to include the revision and semantic version.
2. Extend the Datastore Selection
The YANG notifications subscription OPTIONALLY can be restricted to
the following YANG module revision for future capabilities:
module: Restricts the subscription to one or more YANG module names
with revision and revision-label together for the related streamed
content.
revision: Restricts the subscription to a specific YANG module
revision. Example: "2014-05-08".
revision-label: Restricts the subscription to the latest compatible
YANG module semantic version referenced to. Example: "2.0.0".
When the NETCONF client creates or modifies the subscription using
the RPCs establish-subscription and modify-subscription and the
NETCONF server does not support the revision, the revision-label or
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the combination of revision and revision-label specified in the RPC
request, the NETCONF server MUST return an RPC reply including an
<rpc-error> element as defined in Section 4.3 of [RFC6241] with the
error information populated as follows:
* an "error-type" node of "application".
* an "error-tag" node whose value is a string that corresponds to an
identity associated with the error.
+==========================================+==================+
| Error identity | Uses "error-tag" |
+==========================================+==================+
| revision-unsupported | invalid-value |
+------------------------------------------+------------------+
| revision-label-unsupported | invalid-value |
+------------------------------------------+------------------+
| incompatible-revision-and-revision-label | invalid-value |
+------------------------------------------+------------------+
Table 1: General Subscription Error Identities and
Associated "error-tag" Use
Figure 1 provides an example of a "establish-subscription" RPC call
with YANG revision and datastore-xpath-filter for periodical
subscription. Figure 2 shows the response when the RPC has been
accepted by the NETCONF server and Figure 3 the error sent by the
NETCONF server when the revision is not supported.
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<netconf:rpc message-id="101"
xmlns:netconf="urn:ietf:params:xml:ns:netconf:base:1.0">
<establish-subscription
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications"
xmlns:yp="urn:ietf:params:xml:ns:yang:ietf-yang-push">
xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
<yp:datastore
xmlns:ds="urn:ietf:params:xml:ns:yang:ietf-datastores">
ds:operational
</yp:datastore>
<yp:datastore-xpath-filter
xmlns:ex="https://example.com/sample-data/1.0">
/ex:foo
</yp:datastore-xpath-filter>
<ypr:module-version>
<ypr:module-name>ex:foo</ypr:module-name>
<ypr:revision>2023-09-17</ypr:revision>
</ypr:module-version>
<yp:periodic>
<yp:period>500</yp:period>
</yp:periodic>
</establish-subscription>
</netconf:rpc>
Figure 1: RPC Example for an establish-subscription
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<id
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
52
</id>
</rpc-reply>
Figure 2: RPC Example for a positive establish-subscription response
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<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
xmlns:yp="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
<rpc-error>
<error-type>application</error-type>
<error-tag>operation-failed</error-tag>
<error-severity>error</error-severity>
<error-path xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
<error-info>
<yp:establish-subscription-error-datastore>
<yp:reason xmlns:ypr="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
ypr:revision-unsupported
</yp:reason>
</yp:establish-subscription-error-datastore>
</error-info>
</rpc-error>
</rpc-reply>
Figure 3: RPC Example for an error establish-subscription response
3. Extend the Subscription State Change Notifications
Besides the Subscription ID and the xpath or sub-tree filter
reference as described in Section 2.7 of [RFC8639], the following
metadata objects are part of a "subscription-started" or
"subscription-modified" subscription state change notification.
module: Describes the YANG module names for the related streamed
content.
revision: Describes the YANG module revision as specified in
Section 7.1.9 of [RFC6020] for the related streamed content.
revision-label: Describes the YANG module semantic version as
specified in [I-D.ietf-netmod-yang-semver] for the related
streamed content.
Figure 4 provides an example of a "subscription-modified"
subscription state change notification message with the YANG module
name, revision, revision label and datastore-xpath-filter for
tracking the operational status of a single Ethernet interface (per
[RFC8343]). This subscription state change notification message is
encoded XML [W3C.REC-xml-20081126] over the Network Configuration
Protocol (NETCONF) as per [RFC8640].
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<notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
<eventTime>2023-01-03T10:00:00Z</eventTime>
<subscription-modified
xmlns="urn:ietf:params:xml:ns:yang:ietf-subscribed-notifications">
<id>101</id>
<stream-xpath-filter
xmlns:int="urn:ietf:params:xml:ns:yang:ietf-interfaces">
/int:interfaces
</stream-xpath-filter>
<stream>NETCONF</stream>
<module-version
xmlns="urn:ietf:params:xml:ns:yang:ietf-yang-push-revision">
<module-name>ietf-interfaces</module-name>
<revision>2018-02-20</revision>
<revision-label>2.0.0</revision-label>
</module-version>
</subscription-modified>
</notification>
Figure 4: XML Push Example for a subscription-modified
notification message
Figure 5 provides an example of a JSON encoded, [RFC8259],
subscription state change notification message over HTTPS-based
[I-D.ietf-netconf-https-notif] or UDP-based
[I-D.ietf-netconf-udp-notif] transport for the same subscription.
{
"ietf-restconf:notification" : {
"eventTime": "2023-01-03T10:00:00Z",
"ietf-subscribed-notifications:subscription-modified": {
"id": 101,
"stream-xpath-filter": "/ietf-interfaces:interfaces",
"stream": "NETCONF",
"ietf-yang-push-revision:module-version": [{
"module-name": "ietf-interfaces"
"revision": "2018-02-20",
"revision-label": "2.0.0",
}],
}
}
}
Figure 5: JSON Push Example for a subscription-modified
notification message
4. The "ietf-yang-push-revision" Module
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4.1. Data Model Overview
This YANG module augments the "ietf-yang-push" module with the
module-name, revision and revision-label in the "subscription-
started" and "subscription-modified" subscription state change
notifications and the ability to define the "revision" and "revision-
label" in the "establish-subscription" and "modify-subscription" RPCs
in the datastore push subscription.
4.1.1. Tree View
The following is the YANG tree diagram [RFC8340] for the ietf-yang-
push-revision YANG module
module: ietf-yang-push-revision
augment /sn:filters/sn:stream-filter:
+--rw module-version* [module-name]
+--rw module-name yang:yang-identifier
+--rw revision? rev:revision-date-or-label
+--rw revision-label? ysver:version
augment /sn:filters/yp:selection-filter:
+--rw module-version* [module-name]
+--rw module-name yang:yang-identifier
+--rw revision? rev:revision-date-or-label
+--rw revision-label? ysver:version
augment /sn:establish-subscription/sn:input/sn:target/sn:stream
/sn:stream-filter/sn:within-subscription:
+-- module-version* [module-name]
+-- module-name yang:yang-identifier
+-- revision? rev:revision-date-or-label
+-- revision-label? ysver:version
augment /sn:establish-subscription/sn:input/sn:target/yp:datastore
/yp:selection-filter/yp:within-subscription:
+-- module-version* [module-name]
+-- module-name yang:yang-identifier
+-- revision? rev:revision-date-or-label
+-- revision-label? ysver:version
augment /sn:modify-subscription/sn:input/sn:target/sn:stream
/sn:stream-filter/sn:within-subscription:
+-- module-version* [module-name]
+-- module-name yang:yang-identifier
+-- revision? rev:revision-date-or-label
+-- revision-label? ysver:version
augment /sn:modify-subscription/sn:input/sn:target/yp:datastore
/yp:selection-filter/yp:within-subscription:
+-- module-version* [module-name]
+-- module-name yang:yang-identifier
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+-- revision? rev:revision-date-or-label
+-- revision-label? ysver:version
augment /sn:subscription-started/sn:target/sn:stream
/sn:stream-filter/sn:within-subscription:
+--ro module-version* [module-name]
+--ro module-name yang:yang-identifier
+--ro revision rev:revision-date-or-label
+--ro revision-label? ysver:version
augment /sn:subscription-started/sn:target/yp:datastore
/yp:selection-filter/yp:within-subscription:
+--ro module-version* [module-name]
+--ro module-name yang:yang-identifier
+--ro revision rev:revision-date-or-label
+--ro revision-label? ysver:version
augment /sn:subscription-modified/sn:target/sn:stream
/sn:stream-filter/sn:within-subscription:
+--ro module-version* [module-name]
+--ro module-name yang:yang-identifier
+--ro revision rev:revision-date-or-label
+--ro revision-label? ysver:version
augment /sn:subscription-modified/sn:target/yp:datastore
/yp:selection-filter/yp:within-subscription:
+--ro module-version* [module-name]
+--ro module-name yang:yang-identifier
+--ro revision rev:revision-date-or-label
+--ro revision-label? ysver:version
augment /sn:subscriptions/sn:subscription/sn:target/sn:stream
/sn:stream-filter/sn:within-subscription:
+--rw module-version* [module-name]
+--rw module-name yang:yang-identifier
+--rw revision? rev:revision-date-or-label
+--rw revision-label? ysver:version
augment /sn:subscriptions/sn:subscription/sn:target/yp:datastore
/yp:selection-filter/yp:within-subscription:
+--rw module-version* [module-name]
+--rw module-name yang:yang-identifier
+--rw revision? rev:revision-date-or-label
+--rw revision-label? ysver:version
4.1.2. Full Tree View
The following is the YANG tree diagram [RFC8340] for the ietf-yang-
push-revision augmentation within the ietf-subscribed-notifications,
including the RPCs and notifications.
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module: ietf-yang-push
rpcs:
+---x resync-subscription {on-change}?
+---w input
+---w id sn:subscription-id
notifications:
+---n push-update
| +--ro id? sn:subscription-id
| +--ro datastore-contents? <anydata>
| +--ro incomplete-update? empty
+---n push-change-update {on-change}?
+--ro id? sn:subscription-id
+--ro datastore-changes
| +--ro yang-patch
| +--ro patch-id string
| +--ro comment? string
| +--ro edit* [edit-id]
| +--ro edit-id string
| +--ro operation enumeration
| +--ro target target-resource-offset
| +--ro point? target-resource-offset
| +--ro where? enumeration
| +--ro value? <anydata>
+--ro incomplete-update? empty
module: ietf-subscribed-notifications
+--ro streams
| +--ro stream* [name]
| +--ro name string
| +--ro description? string
| +--ro replay-support? empty {replay}?
| +--ro replay-log-creation-time yang:date-and-time {replay}?
| +--ro replay-log-aged-time? yang:date-and-time {replay}?
+--rw filters
| +--rw stream-filter* [name]
| | +--rw name string
| | +--rw (filter-spec)?
| | | +--:(stream-subtree-filter)
| | | | +--rw stream-subtree-filter? <anydata> {subtree}?
| | | +--:(stream-xpath-filter)
| | | +--rw stream-xpath-filter? yang:xpath1.0 {xpath}?
| | +--rw ypr:module-version* [module-name]
| | +--rw ypr:module-name yang:yang-identifier
| | +--rw ypr:revision? rev:revision-date-or-label
| | +--rw ypr:revision-label? ysver:version
| +--rw yp:selection-filter* [filter-id]
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| +--rw yp:filter-id string
| +--rw (yp:filter-spec)?
| | +--:(yp:datastore-subtree-filter)
| | | +--rw yp:datastore-subtree-filter? <anydata>
| | | {sn:subtree}?
| | +--:(yp:datastore-xpath-filter)
| | +--rw yp:datastore-xpath-filter? yang:xpath1.0
| | {sn:xpath}?
| +--rw ypr:module-version* [module-name]
| +--rw ypr:module-name yang:yang-identifier
| +--rw ypr:revision? rev:revision-date-or-label
| +--rw ypr:revision-label? ysver:version
+--rw subscriptions
+--rw subscription* [id]
+--rw id
| subscription-id
+--rw (target)
| +--:(stream)
| | +--rw (stream-filter)?
| | | +--:(by-reference)
| | | | +--rw stream-filter-name
| | | | stream-filter-ref
| | | +--:(within-subscription)
| | | +--rw (filter-spec)?
| | | | +--:(stream-subtree-filter)
| | | | | +--rw stream-subtree-filter?
| | | | | <anydata> {subtree}?
| | | | +--:(stream-xpath-filter)
| | | | +--rw stream-xpath-filter?
| | | | yang:xpath1.0 {xpath}?
| | | +--rw ypr:module-version* [module-name]
| | | +--rw ypr:module-name
| | | | yang:yang-identifier
| | | +--rw ypr:revision?
| | | | rev:revision-date-or-label
| | | +--rw ypr:revision-label? ysver:version
| | +--rw stream
| | | stream-ref
| | +--ro replay-start-time?
| | | yang:date-and-time {replay}?
| | +--rw configured-replay? empty
| | {configured,replay}?
| +--:(yp:datastore)
| +--rw yp:datastore
| | identityref
| +--rw (yp:selection-filter)?
| +--:(yp:by-reference)
| | +--rw yp:selection-filter-ref
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| | selection-filter-ref
| +--:(yp:within-subscription)
| +--rw (yp:filter-spec)?
| | +--:(yp:datastore-subtree-filter)
| | | +--rw yp:datastore-subtree-filter?
| | | <anydata> {sn:subtree}?
| | +--:(yp:datastore-xpath-filter)
| | +--rw yp:datastore-xpath-filter?
| | yang:xpath1.0 {sn:xpath}?
| +--rw ypr:module-version* [module-name]
| +--rw ypr:module-name
| | yang:yang-identifier
| +--rw ypr:revision?
| | rev:revision-date-or-label
| +--rw ypr:revision-label? ysver:version
+--rw stop-time?
| yang:date-and-time
+--rw dscp?
| inet:dscp {dscp}?
+--rw weighting? uint8
| {qos}?
+--rw dependency?
| subscription-id {qos}?
+--rw transport?
| transport {configured}?
+--rw encoding?
| encoding
+--rw purpose? string
| {configured}?
+--rw (notification-message-origin)? {configured}?
| +--:(interface-originated)
| | +--rw source-interface?
| | if:interface-ref {interface-designation}?
| +--:(address-originated)
| +--rw source-vrf?
| | -> /ni:network-instances/network-instance/name
| | {supports-vrf}?
| +--rw source-address?
| inet:ip-address-no-zone
+--ro configured-subscription-state?
| enumeration {configured}?
+--rw receivers
| +--rw receiver* [name]
| +--rw name string
| +--ro sent-event-records?
| | yang:zero-based-counter64
| +--ro excluded-event-records?
| | yang:zero-based-counter64
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| +--ro state enumeration
| +---x reset {configured}?
| +--ro output
| +--ro time yang:date-and-time
+--rw (yp:update-trigger)?
+--:(yp:periodic)
| +--rw yp:periodic!
| +--rw yp:period centiseconds
| +--rw yp:anchor-time? yang:date-and-time
+--:(yp:on-change) {on-change}?
+--rw yp:on-change!
+--rw yp:dampening-period? centiseconds
+--rw yp:sync-on-start? boolean
+--rw yp:excluded-change* change-type
rpcs:
+---x establish-subscription
| +---w input
| | +---w (target)
| | | +--:(stream)
| | | | +---w (stream-filter)?
| | | | | +--:(by-reference)
| | | | | | +---w stream-filter-name
| | | | | | stream-filter-ref
| | | | | +--:(within-subscription)
| | | | | +---w (filter-spec)?
| | | | | | +--:(stream-subtree-filter)
| | | | | | | +---w stream-subtree-filter?
| | | | | | | <anydata> {subtree}?
| | | | | | +--:(stream-xpath-filter)
| | | | | | +---w stream-xpath-filter?
| | | | | | yang:xpath1.0 {xpath}?
| | | | | +---w ypr:module-version* [module-name]
| | | | | +---w ypr:module-name
| | | | | | yang:yang-identifier
| | | | | +---w ypr:revision?
| | | | | | rev:revision-date-or-label
| | | | | +---w ypr:revision-label? ysver:version
| | | | +---w stream
| | | | | stream-ref
| | | | +---w replay-start-time?
| | | | yang:date-and-time {replay}?
| | | +--:(yp:datastore)
| | | +---w yp:datastore
| | | | identityref
| | | +---w (yp:selection-filter)?
| | | +--:(yp:by-reference)
| | | | +---w yp:selection-filter-ref
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| | | | selection-filter-ref
| | | +--:(yp:within-subscription)
| | | +---w (yp:filter-spec)?
| | | | +--:(yp:datastore-subtree-filter)
| | | | | +---w yp:datastore-subtree-filter?
| | | | | <anydata> {sn:subtree}?
| | | | +--:(yp:datastore-xpath-filter)
| | | | +---w yp:datastore-xpath-filter?
| | | | yang:xpath1.0 {sn:xpath}?
| | | +---w ypr:module-version* [module-name]
| | | +---w ypr:module-name
| | | | yang:yang-identifier
| | | +---w ypr:revision?
| | | | rev:revision-date-or-label
| | | +---w ypr:revision-label? ysver:version
| | +---w stop-time?
| | | yang:date-and-time
| | +---w dscp?
| | | inet:dscp {dscp}?
| | +---w weighting? uint8
| | | {qos}?
| | +---w dependency?
| | | subscription-id {qos}?
| | +---w encoding?
| | | encoding
| | +---w (yp:update-trigger)?
| | +--:(yp:periodic)
| | | +---w yp:periodic!
| | | +---w yp:period centiseconds
| | | +---w yp:anchor-time? yang:date-and-time
| | +--:(yp:on-change) {on-change}?
| | +---w yp:on-change!
| | +---w yp:dampening-period? centiseconds
| | +---w yp:sync-on-start? boolean
| | +---w yp:excluded-change* change-type
| +--ro output
| +--ro id subscription-id
| +--ro replay-start-time-revision? yang:date-and-time
| {replay}?
+---x modify-subscription
| +---w input
| +---w id
| | subscription-id
| +---w (target)
| | +--:(stream)
| | | +---w (stream-filter)?
| | | +--:(by-reference)
| | | | +---w stream-filter-name
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| | | | stream-filter-ref
| | | +--:(within-subscription)
| | | +---w (filter-spec)?
| | | | +--:(stream-subtree-filter)
| | | | | +---w stream-subtree-filter?
| | | | | <anydata> {subtree}?
| | | | +--:(stream-xpath-filter)
| | | | +---w stream-xpath-filter?
| | | | yang:xpath1.0 {xpath}?
| | | +---w ypr:module-version* [module-name]
| | | +---w ypr:module-name
| | | | yang:yang-identifier
| | | +---w ypr:revision?
| | | | rev:revision-date-or-label
| | | +---w ypr:revision-label? ysver:version
| | +--:(yp:datastore)
| | +---w yp:datastore
| | | identityref
| | +---w (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +---w yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +---w (yp:filter-spec)?
| | | +--:(yp:datastore-subtree-filter)
| | | | +---w yp:datastore-subtree-filter?
| | | | <anydata> {sn:subtree}?
| | | +--:(yp:datastore-xpath-filter)
| | | +---w yp:datastore-xpath-filter?
| | | yang:xpath1.0 {sn:xpath}?
| | +---w ypr:module-version* [module-name]
| | +---w ypr:module-name
| | | yang:yang-identifier
| | +---w ypr:revision?
| | | rev:revision-date-or-label
| | +---w ypr:revision-label? ysver:version
| +---w stop-time?
| | yang:date-and-time
| +---w (yp:update-trigger)?
| +--:(yp:periodic)
| | +---w yp:periodic!
| | +---w yp:period centiseconds
| | +---w yp:anchor-time? yang:date-and-time
| +--:(yp:on-change) {on-change}?
| +---w yp:on-change!
| +---w yp:dampening-period? centiseconds
+---x delete-subscription
| +---w input
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| +---w id subscription-id
+---x kill-subscription
+---w input
+---w id subscription-id
notifications:
+---n replay-completed {replay}?
| +--ro id subscription-id
+---n subscription-completed {configured}?
| +--ro id subscription-id
+---n subscription-modified
| +--ro id
| | subscription-id
| +--ro (target)
| | +--:(stream)
| | | +--ro (stream-filter)?
| | | | +--:(by-reference)
| | | | | +--ro stream-filter-name
| | | | | stream-filter-ref
| | | | +--:(within-subscription)
| | | | +--ro (filter-spec)?
| | | | | +--:(stream-subtree-filter)
| | | | | | +--ro stream-subtree-filter?
| | | | | | <anydata> {subtree}?
| | | | | +--:(stream-xpath-filter)
| | | | | +--ro stream-xpath-filter?
| | | | | yang:xpath1.0 {xpath}?
| | | | +--ro ypr:module-version* [module-name]
| | | | +--ro ypr:module-name yang:yang-identifier
| | | | +--ro ypr:revision
| | | | | rev:revision-date-or-label
| | | | +--ro ypr:revision-label? ysver:version
| | | +--ro stream
| | | | stream-ref
| | | +--ro replay-start-time?
| | | yang:date-and-time {replay}?
| | +--:(yp:datastore)
| | +--ro yp:datastore
| | | identityref
| | +--ro (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +--ro yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +--ro (yp:filter-spec)?
| | | +--:(yp:datastore-subtree-filter)
| | | | +--ro yp:datastore-subtree-filter?
| | | | <anydata> {sn:subtree}?
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| | | +--:(yp:datastore-xpath-filter)
| | | +--ro yp:datastore-xpath-filter?
| | | yang:xpath1.0 {sn:xpath}?
| | +--ro ypr:module-version* [module-name]
| | +--ro ypr:module-name yang:yang-identifier
| | +--ro ypr:revision
| | | rev:revision-date-or-label
| | +--ro ypr:revision-label? ysver:version
| +--ro stop-time?
| | yang:date-and-time
| +--ro dscp?
| | inet:dscp {dscp}?
| +--ro weighting? uint8
| | {qos}?
| +--ro dependency?
| | subscription-id {qos}?
| +--ro transport?
| | transport {configured}?
| +--ro encoding? encoding
| +--ro purpose? string
| | {configured}?
| +--ro (yp:update-trigger)?
| +--:(yp:periodic)
| | +--ro yp:periodic!
| | +--ro yp:period centiseconds
| | +--ro yp:anchor-time? yang:date-and-time
| +--:(yp:on-change) {on-change}?
| +--ro yp:on-change!
| +--ro yp:dampening-period? centiseconds
| +--ro yp:sync-on-start? boolean
| +--ro yp:excluded-change* change-type
+---n subscription-resumed
| +--ro id subscription-id
+---n subscription-started {configured}?
| +--ro id
| | subscription-id
| +--ro (target)
| | +--:(stream)
| | | +--ro (stream-filter)?
| | | | +--:(by-reference)
| | | | | +--ro stream-filter-name
| | | | | stream-filter-ref
| | | | +--:(within-subscription)
| | | | +--ro (filter-spec)?
| | | | | +--:(stream-subtree-filter)
| | | | | | +--ro stream-subtree-filter?
| | | | | | <anydata> {subtree}?
| | | | | +--:(stream-xpath-filter)
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| | | | | +--ro stream-xpath-filter?
| | | | | yang:xpath1.0 {xpath}?
| | | | +--ro ypr:module-version* [module-name]
| | | | +--ro ypr:module-name yang:yang-identifier
| | | | +--ro ypr:revision
| | | | | rev:revision-date-or-label
| | | | +--ro ypr:revision-label? ysver:version
| | | +--ro stream
| | | | stream-ref
| | | +--ro replay-start-time?
| | | | yang:date-and-time {replay}?
| | | +--ro replay-previous-event-time?
| | | yang:date-and-time {replay}?
| | +--:(yp:datastore)
| | +--ro yp:datastore
| | | identityref
| | +--ro (yp:selection-filter)?
| | +--:(yp:by-reference)
| | | +--ro yp:selection-filter-ref
| | | selection-filter-ref
| | +--:(yp:within-subscription)
| | +--ro (yp:filter-spec)?
| | | +--:(yp:datastore-subtree-filter)
| | | | +--ro yp:datastore-subtree-filter?
| | | | <anydata> {sn:subtree}?
| | | +--:(yp:datastore-xpath-filter)
| | | +--ro yp:datastore-xpath-filter?
| | | yang:xpath1.0 {sn:xpath}?
| | +--ro ypr:module-version* [module-name]
| | +--ro ypr:module-name yang:yang-identifier
| | +--ro ypr:revision
| | | rev:revision-date-or-label
| | +--ro ypr:revision-label? ysver:version
| +--ro stop-time?
| | yang:date-and-time
| +--ro dscp?
| | inet:dscp {dscp}?
| +--ro weighting? uint8
| | {qos}?
| +--ro dependency?
| | subscription-id {qos}?
| +--ro transport?
| | transport {configured}?
| +--ro encoding? encoding
| +--ro purpose? string
| | {configured}?
| +--ro (yp:update-trigger)?
| +--:(yp:periodic)
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| | +--ro yp:periodic!
| | +--ro yp:period centiseconds
| | +--ro yp:anchor-time? yang:date-and-time
| +--:(yp:on-change) {on-change}?
| +--ro yp:on-change!
| +--ro yp:dampening-period? centiseconds
| +--ro yp:sync-on-start? boolean
| +--ro yp:excluded-change* change-type
+---n subscription-suspended
| +--ro id subscription-id
| +--ro reason identityref
+---n subscription-terminated
+--ro id subscription-id
+--ro reason identityref
4.2. YANG Module
The YANG module has two leaves augmenting the model of Subscription
to YANG Notifications [RFC8639].
<CODE BEGINS> file "ietf-yang-push-revision@2023-10-17.yang"
module ietf-yang-push-revision {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-yang-push-revision";
prefix ypr;
import ietf-subscribed-notifications {
prefix sn;
reference
"RFC 8639: Subscription to YANG Notifications";
}
import ietf-yang-push {
prefix yp;
rev:recommended-min "2019-09-09";
reference
"RFC 8641: Subscriptions to YANG Datastores";
}
import ietf-yang-revisions {
prefix rev;
reference
"RFC XXXX: draft-ietf-netmod-yang-module-versioning-06,
Updated YANG Module Revision Handling";
}
import ietf-yang-types {
prefix yang;
rev:recommended-min "2013-07-15";
reference
"RFC 6991: Common YANG Data Types.";
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}
import ietf-yang-semver {
prefix ysver;
reference
"RFC XXXX: draft-ietf-netmod-yang-semver-08, YANG Semantic
Versioning";
}
organization "IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http:/tools.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Authors: Thomas Graf
<mailto:thomas.graf@swisscom.com>
Benoit Claise
<mailto:benoit.claise@huawei.com>
Alex Huang Feng
<mailto:alex.huang-feng@insa-lyon.fr>";
description
"Defines YANG push event notification header with the revision and
the revision-label. Adds the support of the revision and
revision-label selection in the YANG push subscription RPCs.
Copyright (c) 2023 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, is permitted pursuant to, and subject to the license
terms contained in, the Revised BSD License set forth in Section
4.c of the IETF Trust's Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the RFC
itself for full legal notices.";
revision 2023-10-17 {
description
"First revision";
reference
"RFC XXXX: Support of Versioning in YANG Notifications
Subscription";
}
feature yang-push-revision-supported {
description
"This feature indicates the YANG Subscription Notifications
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supports specifying the list of modules, revisions and
revision-label in the YANG subscription.";
}
// Identities
identity revision-unsupported {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"Revision not supported. This failure can be due to subscribing
to a specific revision not supported by the publisher.";
}
identity revision-label-unsupported {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"Revision-label not supported. This failure can be due to subscribing
to a specific revision-label not supported by the publisher.";
}
identity incompatible-revision-and-revision-label {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
description
"The combination of revision and the revision-label are incompatible.
This failure happens when the revision and the revision-label are both specified
in the RPC and the YANG module supported by the publisher does not support one of
the revision or the revision-label.";
}
grouping yang-push-module-version-config {
description
"This grouping combines the module name, the revision and
revision-label leaves. This grouping is to be used for configuration and the
leaves are not mandatory.";
leaf module-name {
type yang:yang-identifier;
description
"This references the YANG module name.";
}
leaf revision {
type rev:revision-date-or-label;
description
"This references the YANG module revision to be sent in the
subscription.";
}
leaf revision-label {
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type ysver:version;
description
"This references the YANG module semversion to be sent in the
subscription.";
}
}
grouping yang-push-module-version {
description
"This grouping combines the module name, the revision and
revision-label leaves. This grouping is to be used for read-only cases such
as the content of YANG push Notifications. The module-name and revision are
mandatory and MUST be present in the data.";
leaf module-name {
type yang:yang-identifier;
config false;
mandatory true;
description
"This references the YANG module name.";
}
leaf revision {
type rev:revision-date-or-label;
config false;
mandatory true;
description
"This references the YANG module revision of the sent
notification message.";
}
leaf revision-label {
type ysver:version;
description
"This references the YANG module semversion of the sent
notification message.";
}
}
grouping yang-push-module-version-list {
description
"This grouping defines a list of yang-push-module-version
grouping.";
list module-version {
key "module-name";
config false;
description
"List of yang-push-module-version grouping. The revision is
not configurable.";
uses ypr:yang-push-module-version;
}
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}
grouping yang-push-module-version-config-list {
description
"This grouping defines a list of yang-push-module-version-config
grouping.";
list module-version {
key "module-name";
description
"List of yang-push-module-version-config grouping. The revision
is configurable.";
uses ypr:yang-push-module-version-config;
}
}
// Filters
augment "/sn:filters/sn:stream-filter" {
description
"Augment the filters from subscribed notifications with a list
of yang-push-module-version-config grouping.";
uses ypr:yang-push-module-version-config-list;
}
augment "/sn:filters/yp:selection-filter" {
description
"Augment the filters from YANG push with a list of
yang-push-module-version grouping.";
uses ypr:yang-push-module-version-config-list;
}
// Subscription parameters
augment "/sn:establish-subscription/sn:input/sn:target/sn:stream"
+ "/sn:stream-filter/sn:within-subscription" {
description
"Augment the establish-subscription RPC from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-config-list grouping.";
uses ypr:yang-push-module-version-config-list;
}
augment "/sn:establish-subscription/sn:input/sn:target"
+ "/yp:datastore/yp:selection-filter/yp:within-subscription" {
description
"Augment the establish-subscription RPC from the ietf-yang-push
YANG module with the yang-push-module-version-config-list
grouping.";
uses ypr:yang-push-module-version-config-list;
}
augment "/sn:modify-subscription/sn:input/sn:target/sn:stream"
+ "/sn:stream-filter/sn:within-subscription" {
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description
"Augment the modify-subscription RPC from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-config-list grouping.";
uses ypr:yang-push-module-version-config-list;
}
augment "/sn:modify-subscription/sn:input/sn:target/yp:datastore"
+ "/yp:selection-filter/yp:within-subscription" {
description
"Augment the modify-subscription RPC from the ietf-yang-push
YANG module with the yang-push-module-version-config-list
grouping.";
uses ypr:yang-push-module-version-config-list;
}
// Subscription notifications
augment "/sn:subscription-started/sn:target/sn:stream"
+ "/sn:stream-filter/sn:within-subscription" {
description
"Augment the subscription-started notification from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-list grouping.";
uses ypr:yang-push-module-version-list;
}
augment "/sn:subscription-started/sn:target/yp:datastore"
+ "/yp:selection-filter/yp:within-subscription" {
description
"Augment the subscription-started notification from the
ietf-yang-push YANG module with the
yang-push-module-version-list grouping.";
uses ypr:yang-push-module-version-list;
}
augment "/sn:subscription-modified/sn:target/sn:stream"
+ "/sn:stream-filter/sn:within-subscription" {
description
"Augment the subscription-modified notification from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-list grouping.";
uses ypr:yang-push-module-version-list;
}
augment "/sn:subscription-modified/sn:target/yp:datastore"
+ "/yp:selection-filter/yp:within-subscription" {
description
"Augment the subscription-modified notification from the
ietf-yang-push YANG module with the
yang-push-module-version-list grouping.";
uses ypr:yang-push-module-version-list;
}
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// Subscription container
augment "/sn:subscriptions/sn:subscription/sn:target/sn:stream"
+ "/sn:stream-filter/sn:within-subscription" {
description
"Augment the subscriptions RPC container from the
ietf-subscribed-notifications YANG module with the
yang-push-module-version-config-list grouping.";
uses ypr:yang-push-module-version-config-list;
}
augment "/sn:subscriptions/sn:subscription/sn:target/yp:datastore"
+ "/yp:selection-filter/yp:within-subscription" {
description
"Augment the subscription RPC container from ietf-yang-push
YANG module with the yang-push-module-version-config-list grouping.";
uses ypr:yang-push-module-version-config-list;
}
}
<CODE ENDS>
5. IANA Considerations
5.1. IETF XML Registry
This document registers the following URIs in the "IETF XML Registry"
[RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-yang-push-revision
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
5.2. YANG Module Name
This document registers the following YANG modules in the "YANG
Module Names" registry [RFC6020]:
name: ietf-yang-push-revision
namespace: urn:ietf:params:xml:ns:yang:ietf-yang-push-revision
prefix: ypr
reference: RFC-to-be
6. Operational Considerations
A YANG package [I-D.ietf-netmod-yang-packages], specifies a versioned
organizational structure used to manage a set of YANG modules that
collectively defines a package schema. For example, a YANG package
could contain a set of YANG modules required to implement a L3VPN
service on a network node. It offers therefore a complementary
information to the solution in this draft by describing how one
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specific YANG module revision is part of a set of YANG modules.
7. Security Considerations
The security considerations for the YANG notifications subscription
mechanism are described in [RFC8641]. This documents adds no
additional security considerations.
8. Acknowledgements
The authors would like to thank Qiufang Ma and Robert Wilton for
their review and valuable comments.
9. References
9.1. Normative References
[I-D.ietf-netmod-yang-module-versioning]
Wilton, R., Rahman, R., Lengyel, B., Clarke, J., and J.
Sterne, "Updated YANG Module Revision Handling", Work in
Progress, Internet-Draft, draft-ietf-netmod-yang-module-
versioning-10, 17 October 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
yang-module-versioning-10>.
[I-D.ietf-netmod-yang-semver]
Clarke, J., Wilton, R., Rahman, R., Lengyel, B., Sterne,
J., and B. Claise, "YANG Semantic Versioning", Work in
Progress, Internet-Draft, draft-ietf-netmod-yang-semver-
12, 2 October 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
yang-semver-12>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
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[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8639] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Subscription to YANG Notifications",
RFC 8639, DOI 10.17487/RFC8639, September 2019,
<https://www.rfc-editor.org/info/rfc8639>.
[RFC8641] Clemm, A. and E. Voit, "Subscription to YANG Notifications
for Datastore Updates", RFC 8641, DOI 10.17487/RFC8641,
September 2019, <https://www.rfc-editor.org/info/rfc8641>.
9.2. Informative References
[I-D.ietf-netconf-https-notif]
Jethanandani, M. and K. Watsen, "An HTTPS-based Transport
for YANG Notifications", Work in Progress, Internet-Draft,
draft-ietf-netconf-https-notif-13, 4 November 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
https-notif-13>.
[I-D.ietf-netconf-udp-notif]
Zheng, G., Zhou, T., Graf, T., Francois, P., Feng, A. H.,
and P. Lucente, "UDP-based Transport for Configured
Subscriptions", Work in Progress, Internet-Draft, draft-
ietf-netconf-udp-notif-11, 11 October 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
udp-notif-11>.
[I-D.ietf-netmod-yang-packages]
Wilton, R., Rahman, R., Clarke, J., Sterne, J., and B. Wu,
"YANG Packages", Work in Progress, Internet-Draft, draft-
ietf-netmod-yang-packages-03, 4 March 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
yang-packages-03>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
Graf, et al. Expires 22 April 2024 [Page 27]
Internet-Draft YANG Notifications Versioning October 2023
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/info/rfc8343>.
[RFC8640] Voit, E., Clemm, A., Gonzalez Prieto, A., Nilsen-Nygaard,
E., and A. Tripathy, "Dynamic Subscription to YANG Events
and Datastores over NETCONF", RFC 8640,
DOI 10.17487/RFC8640, September 2019,
<https://www.rfc-editor.org/info/rfc8640>.
[W3C.REC-xml-20081126]
Bray, T., Paoli, J., Sperberg-McQueen, M., Maler, E., and
F. Yergeau, "Extensible Markup Language (XML) 1.0 (Fifth
Edition)", World Wide Web Consortium Recommendation REC-
xml-20081126, November 2008,
<https://www.w3.org/TR/2008/REC-xml-20081126>.
Authors' Addresses
Thomas Graf
Swisscom
Binzring 17
CH-8045 Zurich
Switzerland
Email: thomas.graf@swisscom.com
Benoit Claise
Huawei
Email: benoit.claise@huawei.com
Alex Huang Feng
INSA-Lyon
Lyon
France
Email: alex.huang-feng@insa-lyon.fr
Graf, et al. Expires 22 April 2024 [Page 28]
