module ietf-restconf-client {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-restconf-client";
prefix rcc;
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-tcp-client {
prefix tcpc;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tcp-server {
prefix tcps;
reference
"RFC AAAA: YANG Groupings for TCP Clients and TCP Servers";
}
import ietf-tls-client {
prefix tlsc;
reference
"RFC BBBB: YANG Groupings for TLS Clients and TLS Servers";
}
import ietf-http-client {
prefix httpc;
reference
"RFC CCCC: YANG Groupings for HTTP Clients and HTTP Servers";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web:
WG List:
Author: Kent Watsen
Author: Gary Wu ";
description
"This module contains a collection of YANG definitions
for configuring RESTCONF clients.
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
(https://www.rfc-editor.org/info/rfcXXXX); see the RFC
itself for full legal notices.;
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.";
revision 2019-11-02 {
description
"Initial version";
reference
"RFC XXXX: RESTCONF Client and Server Models";
}
// Features
feature https-initiate {
description
"The 'https-initiate' feature indicates that the RESTCONF
client supports initiating HTTPS connections to RESTCONF
servers. This feature exists as HTTPS might not be a
mandatory to implement transport in the future.";
reference
"RFC 8040: RESTCONF Protocol";
}
feature http-listen {
description
"The 'https-listen' feature indicates that the RESTCONF client
supports opening a port to listen for incoming RESTCONF
server call-home connections. This feature exists as not
all RESTCONF clients may support RESTCONF call home.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
feature https-listen {
description
"The 'https-listen' feature indicates that the RESTCONF client
supports opening a port to listen for incoming RESTCONF
server call-home connections. This feature exists as not
all RESTCONF clients may support RESTCONF call home.";
reference
"RFC 8071: NETCONF Call Home and RESTCONF Call Home";
}
// Groupings
grouping restconf-client-grouping {
description
"A reusable grouping for configuring a RESTCONF client
without any consideration for how underlying transport
sessions are established.
This grouping currently doesn't define any nodes.";
}
grouping restconf-client-initiate-stack-grouping {
description
"A reusable grouping for configuring a RESTCONF client
'initiate' protocol stack for a single connection.";
choice transport {
mandatory true;
description
"Selects between available transports. This is a
'choice' statement so as to support additional
transport options to be augmented in.";
case https {
if-feature "https-initiate";
container https {
description
"Specifies HTTPS-specific transport
configuration.";
container tcp-client-parameters {
description
"A wrapper around the TCP client parameters
to avoid name collisions.";
uses tcpc:tcp-client-grouping {
refine "remote-port" {
default "443";
description
"The RESTCONF client will attempt to
connect to the IANA-assigned well-known
port value for 'https' (443) if no value
is specified.";
}
}
}
container tls-client-parameters {
must "client-identity" {
description
"NETCONF/TLS clients MUST pass some
authentication credentials.";
}
description
"A wrapper around the TLS client parameters
to avoid name collisions.";
uses tlsc:tls-client-grouping;
}
container http-client-parameters {
description
"A wrapper around the HTTP client parameters
to avoid name collisions.";
uses httpc:http-client-grouping;
}
container restconf-client-parameters {
description
"A wrapper around the HTTP client parameters
to avoid name collisions.";
uses rcc:restconf-client-grouping;
}
}
}
}
} // restconf-client-initiate-stack-grouping
grouping restconf-client-listen-stack-grouping {
description
"A reusable grouping for configuring a RESTCONF client
'listen' protocol stack for a single connection.";
choice transport {
mandatory true;
description
"Selects between available transports. This is a
'choice' statement so as to support additional
transport options to be augmented in.";
case http {
if-feature "http-listen";
container FIXME {
description "FIXME";
}
}
case https {
if-feature "https-listen";
container https {
description
"HTTPS-specific listening configuration for inbound
connections.";
container tcp-server-parameters {
description
"A wrapper around the TCP client parameters
to avoid name collisions.";
uses tcps:tcp-server-grouping {
refine "local-port" {
default "4336";
description
"The RESTCONF client will listen on the IANA-
assigned well-known port for 'restconf-ch-tls'
(4336) if no value is specified.";
}
}
}
container tls-client-parameters {
must "client-identity" {
description
"NETCONF/TLS clients MUST pass some
authentication credentials.";
}
description
"A wrapper around the TLS client parameters
to avoid name collisions.";
uses tlsc:tls-client-grouping;
}
container http-client-parameters {
description
"A wrapper around the HTTP client parameters
to avoid name collisions.";
uses httpc:http-client-grouping;
}
container restconf-client-parameters {
description
"A wrapper around the RESTCONF client parameters
to avoid name collisions.";
uses rcc:restconf-client-grouping;
}
}
}
}
} // restconf-client-listen-stack-grouping
grouping restconf-client-app-grouping {
description
"A reusable grouping for configuring a RESTCONF client
application that supports both 'initiate' and 'listen'
protocol stacks for a multiplicity of connections.";
container initiate {
if-feature "https-initiate";
presence "Enables client to initiate TCP connections";
description
"Configures client initiating underlying TCP connections.";
list restconf-server {
key "name";
min-elements 1;
description
"List of RESTCONF servers the RESTCONF client is to
maintain simultaneous connections with.";
leaf name {
type string;
description
"An arbitrary name for the RESTCONF server.";
}
container endpoints {
description
"Container for the list of endpoints.";
list endpoint {
key "name";
min-elements 1;
ordered-by user;
description
"A non-empty user-ordered list of endpoints for this
RESTCONF client to try to connect to in sequence.
Defining more than one enables high-availability.";
leaf name {
type string;
description
"An arbitrary name for this endpoint.";
}
uses restconf-client-initiate-stack-grouping;
}
}
container connection-type {
description
"Indicates the RESTCONF client's preference for how
the RESTCONF connection is maintained.";
choice connection-type {
mandatory true;
description
"Selects between available connection types.";
case persistent-connection {
container persistent {
presence "Indicates that a persistent connection
is to be maintained.";
description
"Maintain a persistent connection to the
RESTCONF server. If the connection goes down,
immediately start trying to reconnect to the
RESTCONF server, using the reconnection strategy.
This connection type minimizes any RESTCONF server
to RESTCONF client data-transfer delay, albeit
at the expense of holding resources longer.";
}
}
case periodic-connection {
container periodic {
presence "Indicates that a periodic connection is
to be maintained.";
description
"Periodically connect to the RESTCONF server.
This connection type increases resource
utilization, albeit with increased delay
in RESTCONF server to RESTCONF client
interactions.
The RESTCONF client SHOULD gracefully close
the underlying TLS connection upon completing
planned activities.
In the case that the previous connection is
still active, establishing a new connection
is NOT RECOMMENDED.";
leaf period {
type uint16;
units "minutes";
default "60";
description
"Duration of time between periodic
connections.";
}
leaf anchor-time {
type yang:date-and-time {
// constrained to minute-level granularity
pattern '\d{4}-\d{2}-\d{2}T\d{2}:\d{2}'
+ '(Z|[\+\-]\d{2}:\d{2})';
}
description
"Designates a timestamp before or after which
a series of periodic connections are
determined. The periodic connections occur
at a whole multiple interval from the anchor
time. For example, for an anchor time is 15
minutes past midnight and a period interval
of 24 hours, then a periodic connection will
occur 15 minutes past midnight everyday.";
}
leaf idle-timeout {
type uint16;
units "seconds";
default 120; // two minutes
description
"Specifies the maximum number of seconds
that the underlying TCP session may remain
idle. A TCP session will be dropped if it
is idle for an interval longer than this
number of seconds If set to zero, then the
RESTCONF client will never drop a session
because it is idle.";
}
}
} // periodic-connection
} // connection-type
} // connection-type
container reconnect-strategy {
description
"The reconnection strategy directs how a RESTCONF
client reconnects to a RESTCONF server, after
discovering its connection to the server has
dropped, even if due to a reboot. The RESTCONF
client starts with the specified endpoint and
tries to connect to it max-attempts times before
trying the next endpoint in the list (round
robin).";
leaf start-with {
type enumeration {
enum first-listed {
description
"Indicates that reconnections should start
with the first endpoint listed.";
}
enum last-connected {
description
"Indicates that reconnections should start
with the endpoint last connected to. If
no previous connection has ever been
established, then the first endpoint
configured is used. RESTCONF clients
SHOULD be able to remember the last
endpoint connected to across reboots.";
}
enum random-selection {
description
"Indicates that reconnections should start with
a random endpoint.";
}
}
default "first-listed";
description
"Specifies which of the RESTCONF server's
endpoints the RESTCONF client should start
with when trying to connect to the RESTCONF
server.";
}
leaf max-attempts {
type uint8 {
range "1..max";
}
default "3";
description
"Specifies the number times the RESTCONF client
tries to connect to a specific endpoint before
moving on to the next endpoint in the list
(round robin).";
}
}
}
} // initiate
container listen {
if-feature "http-listen or https-listen";
presence "Enables client to accept call-home connections";
description
"Configures client accepting call-home TCP connections.";
leaf idle-timeout {
type uint16;
units "seconds";
default 3600; // one hour
description
"Specifies the maximum number of seconds that an
underlying TCP session may remain idle. A TCP session
will be dropped if it is idle for an interval longer
then this number of seconds. If set to zero, then
the server will never drop a session because it is
idle. Sessions that have a notification subscription
active are never dropped.";
}
list endpoint {
key "name";
min-elements 1;
description
"List of endpoints to listen for RESTCONF connections.";
leaf name {
type string;
description
"An arbitrary name for the RESTCONF listen endpoint.";
}
uses restconf-client-listen-stack-grouping;
}
}
} // restconf-client-app-grouping
// Protocol accessible node, for servers that implement this
// module.
container restconf-client {
uses restconf-client-app-grouping;
description
"Top-level container for RESTCONF client configuration.";
}
}