module ietf-yang-push {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-yang-push";
prefix yp;
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-subscribed-notifications {
prefix sn;
reference
"draft-ietf-netconf-subscribed-notifications:
Customized Subscriptions to a Publisher's Event Streams
NOTE TO RFC Editor: Please replace above reference to
draft-ietf-netconf-subscribed-notifications with RFC number
when published (i.e. RFC xxxx).";
}
import ietf-datastores {
prefix ds;
reference
"RFC 8342: Network Management Datastore Architecture (NMDA)";
}
import ietf-restconf {
prefix rc;
reference
"RFC 8040: RESTCONF Protocol";
}
import ietf-yang-patch {
prefix ypatch;
reference
"RFC 8072: YANG Patch";
}
organization
"IETF NETCONF Working Group";
contact
"WG Web:
WG List:
Editor: Alexander Clemm
Editor: Eric Voit
Editor: Alberto Gonzalez Prieto
Editor: Ambika Prasad Tripathy
Editor: Einar Nilsen-Nygaard
Editor: Andy Bierman
Editor: Balazs Lengyel
";
description
"This module contains YANG specifications for YANG push.
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 (RFC 2119) (RFC 8174) when, and only when,
they appear in all capitals, as shown here.
Copyright (c) 2019 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 Simplified 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.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
revision 2019-01-29 {
description
"Initial revision.
NOTE TO RFC EDITOR:
(1)Please replace the above revision date to
the date of RFC publication when published.
(2) Please replace the date in the file name
(ietf-yang-push@2019-01-29.yang) to the date of RFC
publication.
(3) Please replace the following reference to
draft-ietf-netconf-yang-push-21 with RFC number when
published (i.e. RFC xxxx).";
reference
"draft-ietf-netconf-yang-push-21";
}
/*
* FEATURES
*/
feature on-change {
description
"This feature indicates that on-change triggered subscriptions
are supported.";
}
/*
* IDENTITIES
*/
/* Error type identities for datastore subscription */
identity resync-subscription-error {
description
"Problem found while attempting to fulfill an
'resync-subscription' RPC request.";
}
identity cant-exclude {
base sn:establish-subscription-error;
description
"Unable to remove the set of 'excluded-changes'. This means
the publisher is unable to restrict 'push-change-update's to
just the change types requested for this subscription.";
}
identity datastore-not-subscribable {
base sn:establish-subscription-error;
base sn:subscription-terminated-reason;
description
"This is not a subscribable datastore.";
}
identity no-such-subscription-resync {
base resync-subscription-error;
description
"Referenced subscription doesn't exist. This may be as a result
of a non-existent subscription ID, an ID which belongs to
another subscriber, or an ID for configured subscription.";
}
identity on-change-unsupported {
base sn:establish-subscription-error;
description
"On-change is not supported for any objects which are
selectable by this filter.";
}
identity on-change-sync-unsupported {
base sn:establish-subscription-error;
description
"Neither sync on start nor resynchronization are supported for
this subscription. This error will be used for two
reasons. First if an 'establish-subscription' RPC includes
'sync-on-start', yet the publisher can't support sending a
'push-update' for this subscription for reasons other than
'on-change-unsupported' or 'sync-too-big'. And second, if the
'resync-subscription' RPC is invoked either for an existing
periodic subscription, or for an on-change subscription which
can't support resynchronization.";
}
identity period-unsupported {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
base sn:subscription-suspended-reason;
description
"Requested time period or dampening-period is too short. This
can be for both periodic and on-change subscriptions (with or
without dampening.) Hints suggesting alternative periods may
be returned as supplemental information.";
}
identity update-too-big {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
base sn:subscription-suspended-reason;
description
"Periodic or on-change push update datatrees exceed a maximum
size limit. Hints on estimated size of what was too big may
be returned as supplemental information.";
}
identity sync-too-big {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
base resync-subscription-error;
base sn:subscription-suspended-reason;
description
"Sync-on-start or resynchronization datatree exceeds a maximum
size limit. Hints on estimated size of what was too big may
be returned as supplemental information.";
}
identity unchanging-selection {
base sn:establish-subscription-error;
base sn:modify-subscription-error;
base sn:subscription-terminated-reason;
description
"Selection filter is unlikely to ever select datatree nodes.
This means that based on the subscriber's current access
rights, the publisher recognizes that the selection filter is
unlikely to ever select datatree nodes which change. Examples
for this might be that node or subtree doesn't exist, read
access is not permitted for a receiver, or static objects that
only change at reboot have been chosen.";
}
/*
* TYPE DEFINITIONS
*/
typedef change-type {
type enumeration {
enum create {
description
"A change that refers to the creation of a new datastore
node.";
}
enum delete {
description
"A change that refers to the deletion of a datastore
node.";
}
enum insert {
description
"A change that refers to the insertion of a new
user-ordered datastore node.";
}
enum move {
description
"A change that refers to a reordering of the target
datastore node.";
}
enum replace {
description
"A change that refers to a replacement of the target
datastore node's value.";
}
}
description
"Specifies different types of datastore changes.";
reference
"RFC 8072 section 2.5, with a delta that it is valid for a
receiver to process an update record which performs a create
operation on a datastore node the receiver believes exists,
or to process a delete on a datastore node the receiver
believes is missing.";
}
typedef selection-filter-ref {
type leafref {
path "/sn:filters/yp:selection-filter/yp:filter-id";
}
description
"This type is used to reference a selection filter.";
}
/*
* GROUP DEFINITIONS
*/
grouping datastore-criteria {
description
"A grouping to define criteria for which selected objects
from a targeted datastore should be included in push
updates.";
leaf datastore {
type identityref {
base ds:datastore;
}
mandatory true;
description
"Datastore from which to retrieve data.";
}
uses selection-filter-objects;
}
grouping selection-filter-types {
description
"This grouping defines the types of selectors for objects
from a datastore.";
choice filter-spec {
description
"The content filter specification for this request.";
anydata datastore-subtree-filter {
if-feature "sn:subtree";
description
"This parameter identifies the portions of the
target datastore to retrieve.";
reference
"RFC 6241: Network Configuration Protocol, Section 6.";
}
leaf datastore-xpath-filter {
if-feature "sn:xpath";
type yang:xpath1.0;
description
"This parameter contains an XPath expression identifying
the portions of the target datastore to retrieve.
If the expression returns a node-set, all nodes in the
node-set are selected by the filter. Otherwise, if the
expression does not return a node-set, the filter
doesn't select any nodes.
The expression is evaluated in the following XPath
context:
o The set of namespace declarations are those in scope
on the 'datastore-xpath-filter' leaf element.
o The set of variable bindings is empty.
o The function library is the core function library, and
the XPath functions defined in section 10 in RFC 7950.
o The context node is the root node of the target
datastore.";
}
}
}
grouping selection-filter-objects {
description
"This grouping defines a selector for objects from a
datastore.";
choice selection-filter {
description
"The source of the selection filter applied to the
subscription. This will come either referenced from a global
list, or be provided within the subscription itself.";
case by-reference {
description
"Incorporate a filter that has been configured
separately.";
leaf selection-filter-ref {
type selection-filter-ref;
mandatory true;
description
"References an existing selection filter which is to be
applied to the subscription.";
}
}
case within-subscription {
description
"Local definition allows a filter to have the same
lifecycle as the subscription.";
uses selection-filter-types;
}
}
}
grouping update-policy-modifiable {
description
"This grouping describes the datastore specific subscription
conditions that can be changed during the lifetime of the
subscription.";
choice update-trigger {
description
"Defines necessary conditions for sending an event record to
the subscriber.";
case periodic {
container periodic {
presence "indicates a periodic subscription";
description
"The publisher is requested to notify periodically the
current values of the datastore as defined by the
selection filter.";
leaf period {
type yang:timeticks;
mandatory true;
description
"Duration of time which should occur between periodic
push updates, in one hundredths of a second.";
}
leaf anchor-time {
type yang:date-and-time;
description
"Designates a timestamp before or after which a series
of periodic push updates are determined. The next
update will take place at a whole multiple interval
from the anchor time. For example, for an anchor time
is set for the top of a particular minute and a period
interval of a minute, updates will be sent at the top
of every minute this subscription is active.";
}
}
}
case on-change {
if-feature "on-change";
container on-change {
presence "indicates an on-change subscription";
description
"The publisher is requested to notify changes in values
in the datastore subset as defined by a selection
filter.";
leaf dampening-period {
type yang:timeticks;
default "0";
description
"Specifies the minimum interval between the assembly of
successive update records for a single receiver of a
subscription. Whenever subscribed objects change, and
a dampening period interval (which may be zero) has
elapsed since the previous update record creation for
a receiver, then any subscribed objects and properties
which have changed since the previous update record
will have their current values marshalled and placed
into a new update record.";
}
}
}
}
}
grouping update-policy {
description
"This grouping describes the datastore-specific subscription
conditions of a subscription.";
uses update-policy-modifiable {
augment "update-trigger/on-change/on-change" {
description
"Includes objects not modifiable once subscription is
established.";
leaf sync-on-start {
type boolean;
default "true";
description
"When this object is set to false, it restricts an
on-change subscription from sending push-update
notifications. When false, pushing a full selection per
the terms of the selection filter MUST NOT be done for
this subscription. Only updates about changes,
i.e. only push-change-update notifications are sent.
When true (default behavior), in order to facilitate a
receiver's synchronization, a full update is sent when
the subscription starts using a push-update
notification. After that, push-change-update
notifications are exclusively sent unless the publisher
chooses to resync the subscription via a new push-update
notification.";
}
leaf-list excluded-change {
type change-type;
description
"Use to restrict which changes trigger an update. For
example, if modify is excluded, only creation and
deletion of objects is reported.";
}
}
}
}
grouping hints {
description
"Parameters associated with some error for a subscription
made upon a datastore.";
leaf period-hint {
type yang:timeticks;
description
"Returned when the requested time period is too short. This
hint can assert a viable period for either a periodic push
cadence or an on-change dampening interval.";
}
leaf filter-failure-hint {
type string;
description
"Information describing where and/or why a provided filter
was unsupportable for a subscription.";
}
leaf object-count-estimate {
type uint32;
description
"If there are too many objects which could potentially be
returned by the selection filter, this identifies the
estimate of the number of objects which the filter would
potentially pass.";
}
leaf object-count-limit {
type uint32;
description
"If there are too many objects which could be returned by
the selection filter, this identifies the upper limit of
the publisher's ability to service for this subscription.";
}
leaf kilobytes-estimate {
type uint32;
description
"If the returned information could be beyond the capacity
of the publisher, this would identify the data size which
could result from this selection filter.";
}
leaf kilobytes-limit {
type uint32;
description
"If the returned information would be beyond the capacity
of the publisher, this identifies the upper limit of the
publisher's ability to service for this subscription.";
}
}
/*
* RPCs
*/
rpc resync-subscription {
if-feature "on-change";
description
"This RPC allows a subscriber of an active on-change
subscription to request a full push of objects.
A successful invocation results in a push-update of all
datastore nodes that the subscriber is permitted to access.
This RPC can only be invoked on the same session on which the
subscription is currently active. In case of an error, a
resync-subscription-error is sent as part of an error
response.";
input {
leaf id {
type sn:subscription-id;
mandatory true;
description
"Identifier of the subscription that is to be resynced.";
}
}
}
rc:yang-data resync-subscription-error {
container resync-subscription-error {
description
"If a 'resync-subscription' RPC fails, the subscription is
not resynced and the RPC error response MUST indicate the
reason for this failure. This yang-data MAY be inserted as
structured data within a subscription's RPC error response
to indicate the failure reason.";
leaf reason {
type identityref {
base resync-subscription-error;
}
mandatory true;
description
"Indicates the reason why the publisher has declined a
request for subscription resynchronization.";
}
uses hints;
}
}
augment "/sn:establish-subscription/sn:input" {
description
"This augmentation adds additional subscription parameters
that apply specifically to datastore updates to RPC input.";
uses update-policy;
}
augment "/sn:establish-subscription/sn:input/sn:target" {
description
"This augmentation adds the datastore as a valid target
for the subscription to RPC input.";
case datastore {
description
"Information specifying the parameters of an request for a
datastore subscription.";
uses datastore-criteria;
}
}
rc:yang-data establish-subscription-datastore-error-info {
container establish-subscription-datastore-error-info {
description
"If any 'establish-subscription' RPC parameters are
unsupportable against the datastore, a subscription is not
created and the RPC error response MUST indicate the reason
why the subscription failed to be created. This yang-data
MAY be inserted as structured data within a subscription's
RPC error response to indicate the failure reason. This
yang-data MUST be inserted if hints are to be provided back
to the subscriber.";
leaf reason {
type identityref {
base sn:establish-subscription-error;
}
description
"Indicates the reason why the subscription has failed to
be created to a targeted datastore.";
}
uses hints;
}
}
augment "/sn:modify-subscription/sn:input" {
description
"This augmentation adds additional subscription parameters
specific to datastore updates.";
uses update-policy-modifiable;
}
augment "/sn:modify-subscription/sn:input/sn:target" {
description
"This augmentation adds the datastore as a valid target
for the subscription to RPC input.";
case datastore {
description
"Information specifying the parameters of an request for a
datastore subscription.";
uses datastore-criteria;
}
}
rc:yang-data modify-subscription-datastore-error-info {
container modify-subscription-datastore-error-info {
description
"This yang-data MAY be provided as part of a subscription's
RPC error response when there is a failure of a
'modify-subscription' RPC which has been made against a
datastore. This yang-data MUST be used if hints are to be
provides back to the subscriber.";
leaf reason {
type identityref {
base sn:modify-subscription-error;
}
description
"Indicates the reason why the subscription has failed to
be modified.";
}
uses hints;
}
}
/*
* NOTIFICATIONS
*/
notification push-update {
description
"This notification contains a push update, containing data
subscribed to via a subscription. This notification is sent
for periodic updates, for a periodic subscription. It can
also be used for synchronization updates of an on-change
subscription. This notification shall only be sent to
receivers of a subscription. It does not constitute a
general-purpose notification that would be subscribable as
part of the NETCONF event stream by any receiver.";
leaf id {
type sn:subscription-id;
description
"This references the subscription which drove the
notification to be sent.";
}
anydata datastore-contents {
description
"This contains the updated data. It constitutes a snapshot
at the time-of-update of the set of data that has been
subscribed to. The snapshot corresponds to the same
snapshot that would be returned in a corresponding get
operation with the same selection filter parameters
applied.";
}
leaf incomplete-update {
type empty;
description
"This is a flag which indicates that not all datastore
nodes subscribed to are included with this update. In
other words, the publisher has failed to fulfill its full
subscription obligations, and despite its best efforts is
providing an incomplete set of objects.";
}
}
notification push-change-update {
if-feature "on-change";
description
"This notification contains an on-change push update. This
notification shall only be sent to the receivers of a
subscription; it does not constitute a general-purpose
notification.";
leaf id {
type sn:subscription-id;
description
"This references the subscription which drove the
notification to be sent.";
}
container datastore-changes {
description
"This contains the set of datastore changes of the target
datastore starting at the time of the previous update, per
the terms of the subscription. The datastore changes are
encoded per RFC 8027 (YANG Patch).";
uses ypatch:yang-patch;
}
leaf incomplete-update {
type empty;
description
"The presence of this object indicates not all changes which
have occurred since the last update are included with this
update. In other words, the publisher has failed to
fulfill its full subscription obligations, for example in
cases where it was not able to keep up with a change
burst.";
}
}
augment "/sn:subscription-started" {
description
"This augmentation adds datastore-specific objects to
the notification that a subscription has started.";
uses update-policy;
}
augment "/sn:subscription-started/sn:target" {
description
"This augmentation allows the datastore to be included as
part of the notification that a subscription has started.";
case datastore {
uses datastore-criteria {
refine "selection-filter/within-subscription" {
description
"Specifies the selection filter and where it originated
from. If the 'selection-filter-ref' is populated, the
filter within the subscription came from the 'filters'
container. Otherwise it is populated in-line as part of
the subscription itself.";
}
}
}
}
augment "/sn:subscription-modified" {
description
"This augmentation adds datastore-specific objects to
the notification that a subscription has been modified.";
uses update-policy;
}
augment "/sn:subscription-modified/sn:target" {
description
"This augmentation allows the datastore to be included as
part of the notification that a subscription has been
modified.";
case datastore {
uses datastore-criteria {
refine "selection-filter/within-subscription" {
description
"Specifies where the selection filter, and where it came
from within the subscription and then populated within
this notification. If the 'selection-filter-ref' is
populated, the filter within the subscription came from
the 'filters' container. Otherwise it is populated
in-line as part of the subscription itself.";
}
}
}
}
/*
* DATA NODES
*/
augment "/sn:filters" {
description
"This augmentation allows the datastore to be included as part
of the selection filtering criteria for a subscription.";
list selection-filter {
key "filter-id";
description
"A list of pre-configured filters that can be applied
to datastore subscriptions.";
leaf filter-id {
type string;
description
"An identifier to differentiate between selection
filters.";
}
uses selection-filter-types;
}
}
augment "/sn:subscriptions/sn:subscription" {
when 'yp:datastore';
description
"This augmentation adds many datastore specific objects to a
subscription.";
uses update-policy;
}
augment "/sn:subscriptions/sn:subscription/sn:target" {
description
"This augmentation allows the datastore to be included as
part of the selection filtering criteria for a subscription.";
case datastore {
uses datastore-criteria;
}
}
}