main UPDATE implement capabilities modules (#1715)

Add ietf-system-capabilities and ietf-notification-capabilities yang
modules.
Subscribe to provide /ietf-system-capabilities:system-capabilities
operational data. Use the SR_SUBSCR_OPER_MERGE flag such as another
application can overwrite the values.
Provide default possible values for all the fields.
Move sub_ntf_ds2ident to common.c.

Link: https://datatracker.ietf.org/doc/html/rfc9196

Signed-off-by: Jeremie Leska <jeremie.leska@6wind.com>

Author: jeremie6wind

modules/ietf-notification-capabilities@2022-02-17.yang

@@ -0,0 +1,262 @@
+module ietf-notification-capabilities {
+  yang-version 1.1;
+  namespace
+    "urn:ietf:params:xml:ns:yang:ietf-notification-capabilities";
+  prefix notc;
+
+  import ietf-yang-push {
+    prefix yp;
+    description
+      "This module requires ietf-yang-push to be implemented.";
+    reference
+      "RFC 8641: Subscription to YANG Notifications for
+       Datastore Updates";
+  }
+  import ietf-system-capabilities {
+    prefix sysc;
+    description
+      "This module requires ietf-system-capabilities to be
+       implemented.";
+    reference
+      "RFC 9196: YANG Modules Describing Capabilities for Systems
+       and Datastore Update Notifications";
+  }
+
+  organization
+    "IETF NETCONF (Network Configuration) Working Group";
+  contact
+    "WG Web:   <https://datatracker.ietf.org/wg/netconf/>
+     WG List:  <mailto:netconf@ietf.org>
+
+     Editor:   Balazs Lengyel
+               <mailto:balazs.lengyel@ericsson.com>";
+  description
+    "This module specifies publisher capabilities related to
+     YANG-Push (RFC 8641).
+
+     The module contains:
+
+     - a specification of the data nodes that support 'on-change' or
+     'periodic' notifications.
+
+     - capabilities related to the throughput of notification data
+     that the publisher can support.  (Note that for a specific
+     subscription, the publisher MAY allow only longer periods
+     or smaller updates depending on, e.g., actual load conditions.)
+
+     Capability values can be specified at the system/publisher
+     level, at the datastore level, or for specific data nodes of
+     a specific datastore (and their contained subtrees), as defined
+     in the ietf-system-capabilities module.
+
+     If different data nodes covered by a single subscription
+     have different values for a specific capability, then using
+     values that are only acceptable for some of these data nodes,
+     but not for others, may result in the rejection of the
+     subscription.
+
+     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) 2022 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 9196
+     (https://www.rfc-editor.org/info/rfc9196); see the RFC itself
+     for full legal notices.";
+
+  revision 2022-02-17 {
+    description
+      "Initial version";
+    reference
+      "RFC 9196: YANG Modules Describing Capabilities for Systems
+       and Datastore Update Notifications";
+  }
+
+  grouping subscription-capabilities {
+    description
+      "Capabilities related to YANG-Push subscriptions
+       and notifications";
+    container subscription-capabilities {
+      description
+        "Capabilities related to YANG-Push subscriptions
+         and notifications";
+      typedef notification-support {
+        type bits {
+          bit config-changes {
+            description
+              "The publisher is capable of sending
+               notifications for 'config true' nodes for the
+               relevant scope and subscription type.";
+          }
+          bit state-changes {
+            description
+              "The publisher is capable of sending
+               notifications for 'config false' nodes for the
+               relevant scope and subscription type.";
+          }
+        }
+        description
+          "Type for defining whether 'on-change' or
+           'periodic' notifications are supported for all data nodes,
+           'config false' data nodes, 'config true' data nodes, or
+           no data nodes.
+
+           The bits config-changes or state-changes have no effect
+           when they are set for a datastore or for a set of nodes
+           that does not contain nodes with the indicated config
+           value.  In those cases, the effect is the same as if no
+           support was declared.  One example of this is indicating
+           support for state-changes for a candidate datastore that
+           has no effect.";
+      }
+
+      leaf max-nodes-per-update {
+        type uint32 {
+          range "1..max";
+        }
+        description
+          "Maximum number of data nodes that can be sent
+           in an update. The publisher MAY support more data nodes
+           but SHOULD support at least this number.
+
+           May be used to avoid the 'update-too-big' error
+           during subscription.";
+        reference
+          "RFC 8641: Subscription to YANG Notifications for
+           Datastore Updates, the 'update-too-big' error/identity";
+      }
+      leaf periodic-notifications-supported {
+        type notification-support;
+        description
+          "Specifies whether the publisher is capable of
+           sending 'periodic' notifications for the selected
+           data nodes, including any subtrees that may exist
+           below them.";
+        reference
+          "RFC 8641: Subscription to YANG Notifications for
+           Datastore Updates, 'periodic' subscription concept";
+      }
+      choice update-period {
+        description
+          "Supported update period value or values for
+           'periodic' subscriptions.";
+        leaf minimum-update-period {
+          type uint32;
+          units "centiseconds";
+          description
+            "Indicates the minimal update period that is
+             supported for a 'periodic' subscription.
+
+             A subscription request to the selected data nodes with
+             a smaller period than what this leaf specifies is
+             likely to result in a 'period-unsupported' error.";
+          reference
+            "RFC 8641: Subscription to YANG Notifications for
+             Datastore Updates, the period leaf in the ietf-yang-push
+             YANG module";
+        }
+        leaf-list supported-update-period {
+          type uint32;
+          units "centiseconds";
+          description
+            "Supported update period values for a 'periodic'
+             subscription.
+
+             A subscription request to the selected data nodes with a
+             period not included in the leaf-list will result in a
+             'period-unsupported' error.";
+          reference
+            "RFC 8641: Subscription to YANG Notifications for
+             Datastore Updates, the period leaf in the ietf-yang-push
+             YANG module";
+        }
+      }
+      leaf on-change-supported {
+        if-feature "yp:on-change";
+        type notification-support;
+        description
+          "Specifies whether the publisher is capable of
+           sending 'on-change' notifications for the selected
+           data nodes and the subtree below them.";
+        reference
+          "RFC 8641: Subscription to YANG Notifications for Datastore
+           Updates, on-change concept";
+      }
+      leaf minimum-dampening-period {
+        if-feature "yp:on-change";
+        type uint32;
+        units "centiseconds";
+        description
+          "The minimum dampening period supported for 'on-change'
+           subscriptions for the selected data nodes.
+
+           If this value is present and greater than zero,
+           that implies dampening is mandatory.";
+        reference
+          "RFC 8641: Subscription to YANG Notifications for
+           Datastore Updates, the dampening-period leaf in the
+           ietf-yang-push YANG module";
+      }
+      leaf-list supported-excluded-change-type {
+        if-feature "yp:on-change";
+        type union {
+          type enumeration {
+            enum none {
+              value -2;
+              description
+                "None of the change types can be excluded.";
+            }
+            enum all {
+              value -1;
+              description
+                "Any combination of change types can be excluded.";
+            }
+          }
+          type yp:change-type;
+        }
+        description
+          "The change types that can be excluded in
+           YANG-Push subscriptions for the selected data nodes.";
+        reference
+          "RFC 8641: Subscription to YANG Notifications for Datastore
+           Updates, the change-type typedef in the ietf-yang-push
+           YANG module";
+      }
+    }
+  }
+
+  augment "/sysc:system-capabilities" {
+    description
+      "Add system level capabilities";
+    uses subscription-capabilities {
+      refine
+        "subscription-capabilities/supported-excluded-change-type" {
+        default "none";
+      }
+    }
+  }
+
+  augment "/sysc:system-capabilities/sysc:datastore-capabilities"
+        + "/sysc:per-node-capabilities" {
+    description
+      "Add datastore and node-level capabilities";
+    uses subscription-capabilities {
+      refine
+        "subscription-capabilities/supported-excluded-change-type" {
+        default "none";
+      }
+    }
+  }
+}