docs/user-guide.rst

   1 .. _netconf-user-guide:
   2
   3 .. |ss| raw:: html
   4
   5    <strike>
   6
   7 .. |se| raw:: html
   8
   9    </strike>
  10
  11 NETCONF User Guide
  12 ==================
  13
  14 Overview
  15 --------
  16
  17 NETCONF is an XML-based protocol used for configuration and monitoring
  18 devices in the network. The base NETCONF protocol is described in
  19 `RFC-6241 <https://www.rfc-editor.org/rfc/rfc6241>`__.
  20
  21 **NETCONF in OpenDaylight:.**
  22
  23 OpenDaylight supports the NETCONF protocol as a northbound server as
  24 well as a southbound plugin. It also includes a set of test tools for
  25 simulating NETCONF devices and clients.
  26
  27 Southbound (netconf-connector)
  28 ------------------------------
  29
  30 The NETCONF southbound plugin is capable of connecting to remote NETCONF
  31 devices and exposing their configuration/operational datastores, RPCs
  32 and notifications as MD-SAL mount points. These mount points allow
  33 applications and remote users (over RESTCONF) to interact with the
  34 mounted devices.
  35
  36 In terms of RFCs, the connector supports:
  37
  38 -  `RFC-6241 <https://www.rfc-editor.org/rfc/rfc6241>`__
  39
  40 -  `RFC-5277 <https://www.rfc-editor.org/rfc/rfc5277>`__
  41
  42 -  `RFC-6022 <https://www.rfc-editor.org/rfc/rfc6022>`__
  43
  44 -  `RFC-7895 <https://www.rfc-editor.org/rfc/rfc7895>`__
  45
  46 **Netconf-connector is fully model-driven (utilizing the YANG modeling
  47 language) so in addition to the above RFCs, it supports any
  48 data/RPC/notifications described by a YANG model that is implemented by
  49 the device.**
  50
  51 .. tip::
  52
  53     NETCONF southbound can be activated by installing
  54     ``odl-netconf-connector-all`` Karaf feature.
  55
  56 .. _netconf-connector:
  57
  58 Netconf-connector configuration
  59 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  60
  61 NETCONF connectors are configured directly through the usage of the
  62 network-topology model. You can configure new NETCONF connectors both
  63 through the NETCONF server for MD-SAL (port 2830) or RESTCONF. This guide
  64 focuses on RESTCONF.
  65
  66 .. important::
  67
  68     Since 2022.09 Chlorine there is only one RESTCONF endpoint:
  69
  70     - | ``http://localhost:8181/rests`` is related to `RFC-8040 <https://www.rfc-editor.org/rfc/rfc8040>`__,
  71       | can be activated by installing ``odl-restconf-nb``
  72        Karaf feature.
  73
  74     | Resources for configuration and operational datastores start
  75      ``/rests/data/``,
  76     | e. g. GET
  77      http://localhost:8181/rests/data/network-topology:network-topology
  78      with response of both datastores. It's allowed to use query
  79      parameters to distinguish between them.
  80     | e. g. GET
  81      http://localhost:8181/rests/data/network-topology:network-topology?content=config
  82      for configuration datastore
  83     | and GET
  84      http://localhost:8181/rests/data/network-topology:network-topology?content=nonconfig
  85      for operational datastore.
  86
  87     | Also if a data node in the path expression is a YANG leaf-list or list
  88      node, the path segment has to be constructed by having leaf-list or
  89      list node name, followed by an "=" character, then followed by the
  90      leaf-list or list value. Any reserved characters must be
  91      percent-encoded.
  92     | e. g. GET
  93      http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf?content=config
  94      for retrieving data from configuration datastore for
  95      topology-netconf value of topology list.
  96
  97 Preconditions
  98 ^^^^^^^^^^^^^
  99
 100 1. OpenDaylight is running
 101
 102 2. In Karaf, you must have the ``odl-netconf-topology`` or
 103    ``odl-netconf-clustered-topology`` feature installed.
 104
 105 3. Feature ``odl-restconf-nb`` must be installed
 106
 107 Spawning new NETCONF connectors
 108 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 109
 110 To create a new NETCONF connector you need to send the following PUT request
 111 to RESTCONF:
 112
 113 .. list-table::
 114    :widths: 1 5
 115
 116    * - rfc8040
 117      - http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=new-netconf-device
 118
 119 You could use the same body to create the new  NETCONF connector with a POST
 120 without specifying the node in the URL:
 121
 122 .. list-table::
 123    :widths: 1 5
 124
 125    * - rfc8040
 126      - http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf
 127
 128 Payload:
 129
 130 .. tabs::
 131
 132    .. tab:: XML
 133
 134       **Content-type:** ``application/xml``
 135
 136       **Accept:** ``application/xml``
 137
 138       **Authentication:** ``admin:admin``
 139
 140       .. code-block:: xml
 141
 142          <node xmlns="urn:TBD:params:xml:ns:yang:network-topology">
 143            <node-id>new-netconf-device</node-id>
 144            <host xmlns="urn:opendaylight:netconf-node-topology">127.0.0.1</host>
 145            <port xmlns="urn:opendaylight:netconf-node-topology">17830</port>
 146            <login-password-unencrypted xmlns="urn:opendaylight:netconf-node-topology">
 147              <username xmlns="urn:opendaylight:netconf-node-topology">admin</username>
 148              <password xmlns="urn:opendaylight:netconf-node-topology">admin</password>
 149            </login-password-unencrypted>
 150            <tcp-only xmlns="urn:opendaylight:netconf-node-topology">false</tcp-only>
 151            <!-- non-mandatory fields with default values, you can safely remove these if you do not wish to override any of these values-->
 152            <reconnect-on-changed-schema xmlns="urn:opendaylight:netconf-node-topology">false</reconnect-on-changed-schema>
 153            <connection-timeout-millis xmlns="urn:opendaylight:netconf-node-topology">20000</connection-timeout-millis>
 154            <max-connection-attempts xmlns="urn:opendaylight:netconf-node-topology">0</max-connection-attempts>
 155            <between-attempts-timeout-millis xmlns="urn:opendaylight:netconf-node-topology">2000</between-attempts-timeout-millis>
 156            <sleep-factor xmlns="urn:opendaylight:netconf-node-topology">1.5</sleep-factor>
 157            <!-- keepalive-delay set to 0 turns off keepalives-->
 158            <keepalive-delay xmlns="urn:opendaylight:netconf-node-topology">120</keepalive-delay>
 159          </node>
 160
 161    .. tab:: JSON
 162
 163       **Content-type:** ``application/json``
 164
 165       **Accept:** ``application/json``
 166
 167       **Authentication:** ``admin:admin``
 168
 169       .. code-block:: json
 170
 171          {
 172              "node": [
 173                  {
 174                      "node-id": "new-netconf-device",
 175                      "netconf-node-topology:port": 17830,
 176                      "netconf-node-topology:reconnect-on-changed-schema": false,
 177                      "netconf-node-topology:connection-timeout-millis": 20000,
 178                      "netconf-node-topology:tcp-only": false,
 179                      "netconf-node-topology:max-connection-attempts": 0,
 180                      "netconf-node-topology:login-password-unencrypted": {
 181                         "netconf-node-topology:username": "admin",
 182                         "netconf-node-topology:password": "admin"
 183                      },
 184                      "netconf-node-topology:sleep-factor": 1.5,
 185                      "netconf-node-topology:host": "127.0.0.1",
 186                      "netconf-node-topology:between-attempts-timeout-millis": 2000,
 187                      "netconf-node-topology:keepalive-delay": 120
 188                  }
 189              ]
 190          }
 191
 192 Note that the device name in <node-id> element must match the last
 193 element of the restconf URL.
 194
 195 Reconfiguring an existing connector
 196 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 197
 198 The steps to reconfigure an existing connector are exactly the same as
 199 when spawning a new connector. The old connection will be disconnected
 200 and a new connector with the new configuration will be created. This needs
 201 to be done with a PUT request because the node already exists. A POST
 202 request will fail for that reason.
 203
 204 Additionally, a PATCH request can be used to modify an existing
 205 configuration. Currently, only yang-patch (`RFC-8072 <https://www.rfc-editor.org/rfc/rfc8072>`__)
 206 is supported. The URL would be the same as the above PUT examples.
 207 Using JSON for the body, the headers needed for the request would
 208 be:
 209
 210 Headers:
 211
 212 -  Accept: application/yang-data+json
 213
 214 -  Content-Type: application/yang-patch+json
 215
 216 Example JSON payload to modify the password entry:
 217
 218 ::
 219
 220     {
 221       "ietf-restconf:yang-patch" : {
 222         "patch-id" : "0",
 223         "edit" : [
 224           {
 225             "edit-id" : "edit1",
 226             "operation" : "merge",
 227             "target" : "",
 228             "value" : {
 229              "node": [
 230                 {
 231                  "node-id": "new-netconf-device",
 232                  "netconf-node-topology:password" : "newpassword"
 233                 }
 234              ]
 235             }
 236          }
 237         ]
 238       }
 239     }
 240
 241 Deleting an existing connector
 242 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 243
 244 To remove an already configured NETCONF connector you need to send a
 245 DELETE request to the same PUT request URL that was used to create the
 246 device:
 247
 248 .. list-table::
 249    :widths: 1 5
 250
 251    * - rfc8040
 252      - http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=new-netconf-device
 253
 254 .. note::
 255
 256     No body is needed to delete the node/device
 257
 258 Connecting to a device not supporting NETCONF monitoring
 259 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 260
 261 The netconf-connector in OpenDaylight relies on ietf-netconf-monitoring
 262 support when connecting to remote NETCONF device. The
 263 ietf-netconf-monitoring support allows netconf-connector to list and
 264 download all YANG schemas that are used by the device. NETCONF connector
 265 can only communicate with a device if it knows the set of used schemas
 266 (or at least a subset). However, some devices use YANG models internally
 267 but do not support NETCONF monitoring. Netconf-connector can also
 268 communicate with these devices, but you have to side load the necessary
 269 yang models into OpenDaylight’s YANG model cache for netconf-connector.
 270 In general there are 2 situations you might encounter:
 271
 272 **1. NETCONF device does not support ietf-netconf-monitoring but it does
 273 list all its YANG models as capabilities in HELLO message**
 274
 275 This could be a device that internally uses only ietf-inet-types YANG
 276 model with revision 2010-09-24. In the HELLO message that is sent from
 277 this device there is this capability reported:
 278
 279 ::
 280
 281     urn:ietf:params:xml:ns:yang:ietf-inet-types?module=ietf-inet-types&revision=2010-09-24
 282
 283 **For such devices you only need to put the schema into folder
 284 cache/schema inside your Karaf distribution.**
 285
 286 .. important::
 287
 288     The file with YANG schema for ietf-inet-types has to be called
 289     ietf-inet-types@2010-09-24.yang. It is the required naming format of
 290     the cache.
 291
 292 **2. NETCONF device does not support ietf-netconf-monitoring and it does
 293 NOT list its YANG models as capabilities in HELLO message**
 294
 295 Compared to device that lists its YANG models in HELLO message, in this
 296 case there would be no capability with ietf-inet-types in the HELLO
 297 message. This type of device basically provides no information about the
 298 YANG schemas it uses so its up to the user of OpenDaylight to properly
 299 configure netconf-connector for this device.
 300
 301 Netconf-connector has an optional configuration attribute called
 302 yang-module-capabilities and this attribute can contain a list of "YANG
 303 module based" capabilities. So by setting this configuration attribute,
 304 it is possible to override the "yang-module-based" capabilities reported
 305 in HELLO message of the device. To do this, we need to modify the
 306 configuration of netconf-connector like in the example below:
 307
 308 .. tabs::
 309
 310    .. tab:: XML
 311
 312       **Content-type:** ``application/xml``
 313
 314       **Accept:** ``application/xml``
 315
 316       **Authentication:** ``admin:admin``
 317
 318       .. code-block:: xml
 319
 320          <node xmlns="urn:TBD:params:xml:ns:yang:network-topology">
 321            <node-id>r5</node-id>
 322            <host xmlns="urn:opendaylight:netconf-node-topology">127.0.0.1</host>
 323            <port xmlns="urn:opendaylight:netconf-node-topology">8305</port>
 324            <login-password-unencrypted xmlns="urn:opendaylight:netconf-node-topology">
 325              <username xmlns="urn:opendaylight:netconf-node-topology">root</username>
 326              <password xmlns="urn:opendaylight:netconf-node-topology">root</password>
 327            </login-password-unencrypted>
 328            <tcp-only xmlns="urn:opendaylight:netconf-node-topology">false</tcp-only>
 329            <keepalive-delay xmlns="urn:opendaylight:netconf-node-topology">30</keepalive-delay>
 330            <yang-module-capabilities xmlns="urn:opendaylight:netconf-node-topology">
 331              <override>true</override>
 332              <capability xmlns="urn:opendaylight:netconf-node-topology">
 333                urn:ietf:params:xml:ns:yang:ietf-inet-types?module=ietf-inet-types&amp;revision=2013-07-15
 334              </capability>
 335            </yang-module-capabilities>
 336          </node>
 337
 338    .. tab:: JSON
 339
 340       **Content-type:** ``application/json``
 341
 342       **Accept:** ``application/json``
 343
 344       **Authentication:** ``admin:admin``
 345
 346       .. code-block:: json
 347
 348          {
 349              "node": [
 350                  {
 351                      "node-id": "device",
 352                      "netconf-node-topology:host": "127.0.0.1",
 353                      "netconf-node-topology:login-password-unencrypted": {
 354                         "netconf-node-topology:password": "root",
 355                         "netconf-node-topology:username": "root"
 356                      },
 357                      "netconf-node-topology:yang-module-capabilities": {
 358                          "override": true,
 359                          "capability": [
 360                              "urn:ietf:params:xml:ns:yang:ietf-inet-types?module=ietf-inet-types&revision=2013-07-15"
 361                          ]
 362                      },
 363                      "netconf-node-topology:port": 8305,
 364                      "netconf-node-topology:tcp-only": false,
 365                      "netconf-node-topology:keepalive-delay": 30
 366                  }
 367              ]
 368          }
 369
 370 **Remember to also put the YANG schemas into the cache folder.**
 371
 372 .. note::
 373
 374     For putting multiple capabilities, you just need to replicate the
 375     capability element inside yang-module-capability element.
 376     Capability element is modeled as a leaf-list. With this
 377     configuration, we would make the remote device report usage of
 378     ietf-inet-types in the eyes of netconf-connector.
 379
 380 Connecting to a device supporting only NETCONF 1.0
 381 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 382
 383 OpenDaylight is schema-based distribution and heavily depends on YANG
 384 models. However some legacy NETCONF devices are not schema-based and
 385 implement just RFC 4741. This type of device does not utilize YANG
 386 models internally and OpenDaylight does not know how to communicate
 387 with such devices, how to validate data, or what the semantics of data
 388 are.
 389
 390 NETCONF connector can communicate also with these devices, but the
 391 trade-offs are worsened possibilities in utilization of NETCONF
 392 mountpoints. Using RESTCONF with such devices is not supported. Also
 393 communicating with schemaless devices from application code is slightly
 394 different.
 395
 396 To connect to schemaless device, there is a optional configuration option
 397 in netconf-node-topology model called schemaless. You have to set this
 398 option to true.
 399
 400 Clustered NETCONF connector
 401 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 402
 403 To spawn NETCONF connectors that are cluster-aware you need to install
 404 the ``odl-netconf-clustered-topology`` karaf feature.
 405
 406 .. warning::
 407
 408     The ``odl-netconf-topology`` and ``odl-netconf-clustered-topology``
 409     features are considered **INCOMPATIBLE**. They both manage the same
 410     space in the datastore and would issue conflicting writes if
 411     installed together.
 412
 413 Configuration of clustered NETCONF connectors works the same as the
 414 configuration through the topology model in the previous section.
 415
 416 When a new clustered connector is configured the configuration gets
 417 distributed among the member nodes and a NETCONF connector is spawned on
 418 each node. From these nodes a master is chosen which handles the schema
 419 download from the device and all the communication with the device. You
 420 will be able to read/write to/from the device from all slave nodes due
 421 to the proxy data brokers implemented.
 422
 423 You can use the ``odl-netconf-clustered-topology`` feature in a single
 424 node scenario as well but the code that uses akka will be used, so for a
 425 scenario where only a single node is used, ``odl-netconf-topology``
 426 might be preferred.
 427
 428 Netconf-connector utilization
 429 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 430
 431 Once the connector is up and running, users can utilize the new mount
 432 point instance. By using RESTCONF or from their application code. This
 433 chapter deals with using RESTCONF and more information for app
 434 developers can be found in the developers guide or in the official
 435 tutorial application **ncmount** that can be found in the coretutorials
 436 project:
 437
 438 -  https://github.com/opendaylight/coretutorials/tree/master/ncmount
 439
 440 Reading data from the device
 441 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 442
 443 Just invoke (no body needed):
 444
 445 GET
 446 http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=new-netconf-device/yang-ext:mount?content=nonconfig
 447
 448 This will return the entire content of operation datastore from the
 449 device. To view just the configuration datastore, change **nonconfig**
 450 in this URL to **config**.
 451
 452 Writing configuration data to the device
 453 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 454
 455 In general, you cannot simply write any data you want to the device. The
 456 data have to conform to the YANG models implemented by the device. In
 457 this example we are adding a new interface-configuration to the mounted
 458 device (assuming the device supports Cisco-IOS-XR-ifmgr-cfg YANG model).
 459 In fact this request comes from the tutorial dedicated to the
 460 **ncmount** tutorial app.
 461
 462 POST
 463 http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=new-netconf-device/yang-ext:mount/Cisco-IOS-XR-ifmgr-cfg:interface-configurations
 464
 465 ::
 466
 467     <interface-configuration xmlns="http://cisco.com/ns/yang/Cisco-IOS-XR-ifmgr-cfg">
 468         <active>act</active>
 469         <interface-name>mpls</interface-name>
 470         <description>Interface description</description>
 471         <bandwidth>32</bandwidth>
 472         <link-status></link-status>
 473     </interface-configuration>
 474
 475 Should return 200 response code with no body.
 476
 477 .. tip::
 478
 479     This call is transformed into a couple of NETCONF RPCs. Resulting
 480     NETCONF RPCs that go directly to the device can be found in the
 481     OpenDaylight logs after invoking ``log:set TRACE
 482     org.opendaylight.controller.sal.connect.netconf`` in the Karaf
 483     shell. Seeing the NETCONF RPCs might help with debugging.
 484
 485 This request is very similar to the one where we spawned a new netconf
 486 device. That’s because we used the loopback netconf-connector to write
 487 configuration data into config-subsystem datastore and config-subsystem
 488 picked it up from there.
 489
 490 Invoking custom RPC
 491 ^^^^^^^^^^^^^^^^^^^
 492
 493 Devices can implement any additional RPC and as long as it provides YANG
 494 models for it, it can be invoked from OpenDaylight. Following example
 495 shows how to invoke the get-schema RPC (get-schema is quite common among
 496 netconf devices). Invoke:
 497
 498 POST
 499 http://localhost:8181/rests/operations/network-topology:network-topology/topology=topology-netconf/node=new-netconf-device/yang-ext:mount/ietf-netconf-monitoring:get-schema
 500
 501 ::
 502
 503     <input xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-monitoring">
 504       <identifier>ietf-yang-types</identifier>
 505       <version>2013-07-15</version>
 506     </input>
 507
 508 This call should fetch the source for ietf-yang-types YANG model from
 509 the mounted device.
 510
 511 Receiving Netconf Device Notifications on a http client
 512 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 513
 514 Devices emit netconf alarms and notifications in certain situations, which can demand
 515 attention from Device Administration. The notifications are received as Netconf messages on an
 516 active Netconf session.
 517
 518 Opendaylight provides the way to stream the device notifications over a http session.
 519
 520 - Step 1: Mount the device (assume node name is test_device)
 521
 522 - Step 2: Wait for the device to be connected.
 523
 524 - Step 3: Create the Subscription for notification on the active session.
 525
 526  .. code-block::
 527
 528     POST
 529     http://localhost:8181/rests/operations/network-topology:network-topology/topology=topology-netconf/node=test_device/yang-ext:mount/notifications:create-subscription
 530     Content-Type: application/json
 531     Accept: application/json
 532
 533  .. code-block:: json
 534
 535     {
 536       "input": {
 537         "stream": "NETCONF"
 538        }
 539     }
 540
 541 - Step 4: Create the http Stream for the events.
 542
 543 .. code-block::
 544
 545     POST
 546     http://localhost:8181/rests/operations/odl-device-notification:subscribe-device-notification
 547     Content-Type: application/json
 548     Accept: application/json
 549
 550 .. code-block:: json
 551
 552     {
 553       "input": {
 554          "path":"/network-topology:network-topology/topology[topology-id='topology-netconf']/node[node-id='test_device']"
 555       }
 556     }
 557
 558 The response suggests the http url for reading the notifications.
 559
 560 .. code-block:: json
 561
 562     {
 563        "odl-device-notification:output": {
 564             "stream-path": "http://localhost:8181/rests/notif/test_device?notificationType=test_device"
 565         }
 566     }
 567
 568 - Step 5: User can access the url in the response and the notifications will be as follows.
 569
 570 .. code-block::
 571
 572     GET
 573     http://localhost:8181/rests/notif/test_device?notificationType=test_device
 574     Content-Type: application/xml
 575     Accept: application/xml
 576
 577
 578 .. code-block:: xml
 579
 580     : ping
 581
 582     : ping
 583
 584     : ping
 585
 586     : ping
 587
 588     : ping
 589
 590     data: <notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0"><eventTime>2022-06-17T07:01:08.60228Z</eventTime><netconf-session-start xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-notifications"><username>root</username><source-host>127.0.0.1</source-host><session-id>2</session-id></netconf-session-start></notification>
 591
 592     data: <notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0"><eventTime>2022-06-17T07:01:12.458258Z</eventTime><netconf-session-end xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-notifications"><username>root</username><source-host>127.0.0.1</source-host><termination-reason>closed</termination-reason><session-id>2</session-id></netconf-session-end></notification>
 593
 594 Change event notification subscription tutorial
 595 -----------------------------------------------
 596
 597 Subscribing to data change notifications makes it possible to obtain
 598 notifications about data manipulation (insert, change, delete) which are
 599 done on any specified **path** of any specified **datastore** with
 600 specific **scope**. In following examples *{odlAddress}* is address of
 601 server where ODL is running and *{odlPort}* is port on which
 602 OpenDaylight is running. OpenDaylight offers two methods for receiving notifications:
 603 Server-Sent Events (SSE) and WebSocket. SSE is the default notification mechanism used in OpenDaylight.
 604
 605 SSE notifications subscription process
 606 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 607
 608 In this section we will learn what steps need to be taken in order to
 609 successfully subscribe to data change event notifications.
 610
 611 Create stream
 612 ^^^^^^^^^^^^^
 613
 614 In order to use event notifications you first need to call RPC that
 615 creates notification stream that you can later listen to. You need to
 616 provide three parameters to this RPC:
 617
 618 -  **path**: data store path that you plan to listen to. You can
 619    register listener on containers, lists and leaves.
 620
 621 -  **datastore**: data store type. *OPERATIONAL* or *CONFIGURATION*.
 622
 623 -  **scope**: Represents scope of data change. Possible options are:
 624
 625    -  BASE: only changes directly to the data tree node specified in the
 626       path will be reported
 627
 628    -  ONE: changes to the node and to direct child nodes will be
 629       reported
 630
 631    -  SUBTREE: changes anywhere in the subtree starting at the node will
 632       be reported
 633
 634 The RPC to create the stream can be invoked via RESTCONF like this:
 635
 636 ::
 637
 638     OPERATION: POST
 639     URI:  http://{odlAddress}:{odlPort}/rests/operations/sal-remote:create-data-change-event-subscription
 640     HEADER: Content-Type=application/json
 641             Accept=application/json
 642
 643 .. code-block:: json
 644
 645        {
 646            "input": {
 647                "path": "/toaster:toaster/toaster:toasterStatus",
 648                "sal-remote-augment:datastore": "OPERATIONAL",
 649                "sal-remote-augment:scope": "ONE"
 650            }
 651        }
 652
 653 The response should look something like this:
 654
 655 .. code-block:: json
 656
 657     {
 658         "sal-remote:output": {
 659             "stream-name": "data-change-event-subscription/toaster:toaster/toaster:toasterStatus/datastore=CONFIGURATION/scope=SUBTREE"
 660         }
 661     }
 662
 663 **stream-name** is important because you will need to use it when you
 664 subscribe to the stream in the next step.
 665
 666 .. note::
 667
 668     Internally, this will create a new listener for *stream-name* if it
 669     did not already exist.
 670
 671 Subscribe to stream
 672 ^^^^^^^^^^^^^^^^^^^
 673
 674 In order to subscribe to stream and obtain SSE location you need
 675 to call *GET* on your stream path. The URI should generally be
 676 `http://{odlAddress}:{odlPort}/rests/data/ietf-restconf-monitoring:restconf-state/streams/stream/{streamName}`,
 677 where *{streamName}* is the *stream-name* parameter contained in
 678 response from *create-data-change-event-subscription* RPC from the
 679 previous step.
 680
 681 ::
 682
 683    OPERATION: GET
 684    URI: http://{odlAddress}:{odlPort}/rests/data/ietf-restconf-monitoring:restconf-state/streams/stream/data-change-event-subscription/toaster:toaster/datastore=CONFIGURATION/scope=SUBTREE
 685
 686 The subscription call may be modified with the following query parameters defined in the RESTCONF RFC:
 687
 688 -  `filter <https://www.rfc-editor.org/rfc/rfc8040#section-4.8.4>`__
 689
 690 -  `start-time <https://www.rfc-editor.org/rfc/rfc8040#section-4.8.7>`__
 691
 692 -  `end-time <https://www.rfc-editor.org/rfc/rfc8040#section-4.8.8>`__
 693
 694 In addition, the following ODL extension query parameter is supported:
 695
 696 :odl-leaf-nodes-only:
 697   If this parameter is set to "true", create and update notifications will only
 698   contain the leaf nodes modified instead of the entire subscription subtree.
 699   This can help in reducing the size of the notifications.
 700
 701 :odl-skip-notification-data:
 702   If this parameter is set to "true", create and update notifications will only
 703   contain modified leaf nodes without data.
 704   This can help in reducing the size of the notifications.
 705
 706 The response should look something like this:
 707
 708 .. code-block:: json
 709
 710     {
 711         "subscribe-to-notification:location": "http://localhost:8181/rests/notif/data-change-event-subscription/network-topology:network-topology/datastore=CONFIGURATION/scope=SUBTREE"
 712     }
 713
 714 .. note::
 715
 716     During this phase there is an internal check for to see if a
 717     listener for the *stream-name* from the URI exists. If not, new a
 718     new listener is registered with the DOM data broker.
 719
 720 Receive notifications
 721 ^^^^^^^^^^^^^^^^^^^^^
 722
 723 Once you got SSE location you can now connect to it and
 724 start receiving data change events. The request should look something like this:
 725
 726 ::
 727
 728     curl -v -X GET  http://localhost:8181/rests/notif/data-change-event-subscription/toaster:toaster/toasterStatus/datastore=OPERATIONAL/scope=ONE  -H "Content-Type: text/event-stream" -H "Authorization: Basic YWRtaW46YWRtaW4="
 729
 730
 731 WebSocket notifications subscription process
 732 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 733
 734 Enabling WebSocket notifications in OpenDaylight requires a manual setup before starting the application.
 735 The following steps can be followed to enable WebSocket notifications in OpenDaylight:
 736
 737 1. Open the file `restconf8040.cfg`, at `etc/` folder inside your Karaf distribution.
 738 2. Locate the `use-sse` configuration parameter and change its value from `true` to `false`.
 739 3. Uncomment the `use-sse` parameter if it is commented out.
 740 4. Save the changes made to the `restconf8040.cfg` file.
 741 5. Restart OpenDaylight if it is already running.
 742
 743 Once these steps are completed, WebSocket notifications will be enabled in OpenDaylight,
 744 and they can be used for receiving notifications instead of SSE.
 745
 746 WebSocket Notifications subscription process is the same as SSE until you receive a location of WebSocket.
 747 You can follow steps given above and after subscribing to a notification stream over WebSocket,
 748 you will receive a response indicating that the subscription was successful:
 749
 750 .. code-block:: json
 751
 752     {
 753         "subscribe-to-notification:location": "ws://localhost:8181/rests/notif/data-change-event-subscription/network-topology:network-topology/datastore=CONFIGURATION/scope=SUBTREE"
 754     }
 755
 756 You can use this WebSocket to listen to data
 757 change notifications. To listen to notifications you can use a
 758 JavaScript client or if you are using chrome browser you can use the
 759 `Simple WebSocket
 760 Client <https://chrome.google.com/webstore/detail/simple-websocket-client/pfdhoblngboilpfeibdedpjgfnlcodoo>`__.
 761
 762 Also, for testing purposes, there is simple Java application named
 763 WebSocketClient. The application is placed in the
 764 */restconf/websocket-client* project. It accepts a WebSocket URI
 765 as an input parameter. After starting the utility (WebSocketClient
 766 class directly in Eclipse/InteliJ Idea) received notifications should be
 767 displayed in console.
 768
 769 Notifications are always in XML format and look like this:
 770
 771 .. code-block:: xml
 772
 773     <notification xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
 774         <eventTime>2014-09-11T09:58:23+02:00</eventTime>
 775         <data-changed-notification xmlns="urn:opendaylight:params:xml:ns:yang:controller:md:sal:remote">
 776             <data-change-event>
 777                 <path xmlns:meae="http://netconfcentral.org/ns/toaster">/meae:toaster</path>
 778                 <operation>updated</operation>
 779                 <data>
 780                    <!-- updated data -->
 781                 </data>
 782             </data-change-event>
 783         </data-changed-notification>
 784     </notification>
 785
 786 Example use case
 787 ~~~~~~~~~~~~~~~~
 788
 789 The typical use case is listening to data change events to update web
 790 page data in real time. In this tutorial we will be using toaster as the
 791 base.
 792
 793 When you call *make-toast* RPC, it sets *toasterStatus* to "down" to
 794 reflect that the toaster is busy making toast. When it finishes,
 795 *toasterStatus* is set to "up" again. We will listen to these toaster
 796 status changes in data store and will reflect it on our web page in
 797 real-time thanks to WebSocket data change notification.
 798
 799 Simple javascript client implementation
 800 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 801
 802 We will create a simple JavaScript web application that will listen for
 803 updates on *toasterStatus* leaf and update some elements of our web page
 804 according to the new toaster status state.
 805
 806 Create stream
 807 ^^^^^^^^^^^^^
 808
 809 First you need to create stream that you are planning to subscribe to.
 810 This can be achieved by invoking "create-data-change-event-subscription"
 811 RPC on RESTCONF via AJAX request. You need to provide data store
 812 **path** that you plan to listen on, **data store type** and **scope**.
 813 If the request is successful you can extract the **stream-name** from
 814 the response and use that to subscribe to the newly created stream. The
 815 *{username}* and *{password}* fields represent the credentials that you
 816 use to connect to OpenDaylight via RESTCONF:
 817
 818 .. note::
 819
 820     The default user name and password are "admin".
 821
 822 .. code-block:: javascript
 823
 824     function createStream() {
 825         $.ajax(
 826             {
 827                 url: 'http://{odlAddress}:{odlPort}/rests/operations/sal-remote:create-data-change-event-subscription',
 828                 type: 'POST',
 829                 headers: {
 830                   'Authorization': 'Basic ' + btoa('{username}:{password}'),
 831                   'Content-Type': 'application/json'
 832                 },
 833                 data: JSON.stringify(
 834                     {
 835                         'input': {
 836                             'path': '/toaster:toaster/toaster:toasterStatus',
 837                             'sal-remote-augment:datastore': 'OPERATIONAL',
 838                             'sal-remote-augment:scope': 'ONE'
 839                         }
 840                     }
 841                 )
 842             }).done(function (data) {
 843                 // this function will be called when ajax call is executed successfully
 844                 subscribeToStream(data.output['stream-name']);
 845             }).fail(function (data) {
 846                 // this function will be called when ajax call fails
 847                 console.log("Create stream call unsuccessful");
 848             })
 849     }
 850
 851 Subscribe to stream
 852 ^^^^^^^^^^^^^^^^^^^
 853
 854 The Next step is to subscribe to the stream. To subscribe to the stream
 855 you need to call *GET* on
 856 *http://{odlAddress}:{odlPort}/rests/data/ietf-restconf-monitoring:restconf-state/streams/stream/{stream-name}*.
 857 If the call is successful, you get WebSocket address for this stream in
 858 **Location** parameter inside response header. You can get response
 859 header by calling *getResponseHeader(\ *Location*)* on HttpRequest
 860 object inside *done()* function call:
 861
 862 .. code-block:: javascript
 863
 864     function subscribeToStream(streamName) {
 865         $.ajax(
 866             {
 867                 url: 'http://{odlAddress}:{odlPort}/rests/data/ietf-restconf-monitoring:restconf-state/streams/stream/' + streamName;
 868                 type: 'GET',
 869                 headers: {
 870                   'Authorization': 'Basic ' + btoa('{username}:{password}'),
 871                 }
 872             }
 873         ).done(function (data, textStatus, httpReq) {
 874             // we need function that has http request object parameter in order to access response headers.
 875             listenToNotifications(httpReq.getResponseHeader('Location'));
 876         }).fail(function (data) {
 877             console.log("Subscribe to stream call unsuccessful");
 878         });
 879     }
 880
 881 Receive notifications
 882 ^^^^^^^^^^^^^^^^^^^^^
 883
 884 Once you have WebSocket server location you can now connect to it and
 885 start receiving data change events. You need to define functions that
 886 will handle events on WebSocket. In order to process incoming events
 887 from OpenDaylight you need to provide a function that will handle
 888 *onmessage* events. The function must have one parameter that represents
 889 the received event object. The event data will be stored in
 890 *event.data*. The data will be in an XML format that you can then easily
 891 parse using jQuery.
 892
 893 .. code-block:: javascript
 894
 895     function listenToNotifications(socketLocation) {
 896         try {
 897             var notificatinSocket = new WebSocket(socketLocation);
 898
 899             notificatinSocket.onmessage = function (event) {
 900                 // we process our received event here
 901                 console.log('Received toaster data change event.');
 902                 $($.parseXML(event.data)).find('data-change-event').each(
 903                     function (index) {
 904                         var operation = $(this).find('operation').text();
 905                         if (operation == 'updated') {
 906                             // toaster status was updated so we call function that gets the value of toasterStatus leaf
 907                             updateToasterStatus();
 908                             return false;
 909                         }
 910                     }
 911                 );
 912             }
 913             notificatinSocket.onerror = function (error) {
 914                 console.log("Socket error: " + error);
 915             }
 916             notificatinSocket.onopen = function (event) {
 917                 console.log("Socket connection opened.");
 918             }
 919             notificatinSocket.onclose = function (event) {
 920                 console.log("Socket connection closed.");
 921             }
 922             // if there is a problem on socket creation we get exception (i.e. when socket address is incorrect)
 923         } catch(e) {
 924             alert("Error when creating WebSocket" + e );
 925         }
 926     }
 927
 928 The *updateToasterStatus()* function represents function that calls
 929 *GET* on the path that was modified and sets toaster status in some web
 930 page element according to received data. After the WebSocket connection
 931 has been established you can test events by calling make-toast RPC via
 932 RESTCONF.
 933
 934 .. note::
 935
 936     for more information about WebSockets in JavaScript visit `Writing
 937     WebSocket client
 938     applications <https://developer.mozilla.org/en-US/docs/Web/API/WebSockets_API/Writing_WebSocket_client_applications>`__
 939
 940 Netconf-connector + Netopeer
 941 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 942
 943 `Netopeer <https://github.com/cesnet/netopeer>`__ (an open-source
 944 NETCONF server) can be used for testing/exploring NETCONF southbound in
 945 OpenDaylight.
 946
 947 Netopeer installation
 948 ^^^^^^^^^^^^^^^^^^^^^
 949
 950 A `Docker <https://www.docker.com/>`__ container with netopeer will be
 951 used in this guide. To install Docker and start the `netopeer
 952 image <https://hub.docker.com/r/sysrepo/sysrepo-netopeer2>`__ perform
 953 following steps:
 954
 955 1. Install docker https://docs.docker.com/get-started/
 956
 957 2. Start the netopeer image:
 958
 959    ::
 960
 961        docker run -it --name sysrepo -p 830:830 --rm sysrepo/sysrepo-netopeer2:latest
 962
 963 3. Verify netopeer is running by invoking (netopeer should send its
 964    HELLO message right away:
 965
 966    ::
 967
 968        ssh root@localhost -p 830 -s netconf
 969        (password root)
 970
 971 Mounting netopeer NETCONF server
 972 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 973
 974 Preconditions:
 975
 976 -  OpenDaylight is started with features ``odl-restconf-all`` and
 977    ``odl-netconf-connector-all``.
 978
 979 -  Netopeer is up and running in docker
 980
 981 Now just follow the section: `Spawning new NETCONF connectors`_.
 982 In the payload change the:
 983
 984 -  name, e.g., to netopeer
 985
 986 -  username/password to your system credentials
 987
 988 -  ip to localhost
 989
 990 -  port to 1831.
 991
 992 After netopeer is mounted successfully, its configuration can be read
 993 using RESTCONF by invoking:
 994
 995 GET
 996 http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=netopeer/yang-ext:mount?content:config
 997
 998 Northbound (NETCONF servers)
 999 ----------------------------
1000
1001 OpenDaylight provides 2 types of NETCONF servers:
1002
1003 -  **NETCONF server for config-subsystem (listening by default on port
1004    1830)**
1005
1006    -  Serves as a default interface for config-subsystem and allows
1007       users to spawn/reconfigure/destroy modules (or applications) in
1008       OpenDaylight
1009
1010 -  **NETCONF server for MD-SAL (listening by default on port 2830)**
1011
1012    -  Serves as an alternative interface for MD-SAL (besides RESTCONF)
1013       and allows users to read/write data from MD-SAL’s datastore and to
1014       invoke its rpcs (NETCONF notifications are not available in the
1015       Boron release of OpenDaylight)
1016
1017 .. note::
1018
1019     The reason for having 2 NETCONF servers is that config-subsystem and
1020     MD-SAL are 2 different components of OpenDaylight and require
1021     different approaches for NETCONF message handling and data
1022     translation. These 2 components will probably merge in the future.
1023
1024 .. note::
1025
1026     Since Nitrogen release, there has been performance regression in NETCONF
1027     servers accepting SSH connections. While opening a connection takes
1028     less than 10 seconds on Carbon, on Nitrogen time can increase up to
1029     60 seconds. Please see https://jira.opendaylight.org/browse/ODLPARENT-112
1030
1031 NETCONF server for config-subsystem
1032 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1033
1034 This NETCONF server is the primary interface for config-subsystem. It
1035 allows the users to interact with config-subsystem in a standardized
1036 NETCONF manner.
1037
1038 In terms of RFCs, these are supported:
1039
1040 -  `RFC-6241 <https://www.rfc-editor.org/rfc/rfc6241>`__
1041
1042 -  `RFC-5277 <https://www.rfc-editor.org/rfc/rfc5277>`__
1043
1044 -  `RFC-6470 <https://www.rfc-editor.org/rfc/rfc6470>`__
1045
1046    -  (partially, only the schema-change notification is available in
1047       Boron release)
1048
1049 -  `RFC-6022 <https://www.rfc-editor.org/rfc/rfc6022>`__
1050
1051 For regular users it is recommended to use RESTCONF + the
1052 controller-config loopback mountpoint instead of using pure NETCONF. How
1053 to do that is specific for each component/module/application in
1054 OpenDaylight and can be found in their dedicated user guides.
1055
1056 NETCONF server for MD-SAL
1057 ~~~~~~~~~~~~~~~~~~~~~~~~~
1058
1059 This NETCONF server is just a generic interface to MD-SAL in
1060 OpenDaylight. It uses the standard MD-SAL APIs and serves as an
1061 alternative to RESTCONF. It is fully model-driven and supports any data
1062 and rpcs that are supported by MD-SAL.
1063
1064 In terms of RFCs, these are supported:
1065
1066 -  `RFC-6241 <https://www.rfc-editor.org/rfc/rfc6241>`__
1067
1068 -  `RFC-6022 <https://www.rfc-editor.org/rfc/rfc6022>`__
1069
1070 -  `RFC-7895 <https://www.rfc-editor.org/rfc/rfc7895>`__
1071
1072 Notifications over NETCONF are not supported in the Boron release.
1073
1074 .. tip::
1075
1076     Install NETCONF northbound for MD-SAL by installing feature:
1077     ``odl-netconf-mdsal`` in karaf. Default binding port is **2830**.
1078
1079 Configuration
1080 ^^^^^^^^^^^^^
1081
1082 The default configuration can be found in file: *08-netconf-mdsal.xml*.
1083 The file contains the configuration for all necessary dependencies and a
1084 single SSH endpoint starting on port 2830. There is also a (by default
1085 disabled) TCP endpoint. It is possible to start multiple endpoints at
1086 the same time either in the initial configuration file or while
1087 OpenDaylight is running.
1088
1089 The credentials for SSH endpoint can also be configured here, the
1090 defaults are admin/admin. Credentials in the SSH endpoint are not yet
1091 managed by the centralized AAA component and have to be configured
1092 separately.
1093
1094 Verifying MD-SAL’s NETCONF server
1095 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1096
1097 After the NETCONF server is available it can be examined by a command
1098 line ssh tool:
1099
1100 ::
1101
1102     ssh admin@localhost -p 2830 -s netconf
1103
1104 The server will respond by sending its HELLO message and can be used as
1105 a regular NETCONF server from then on.
1106
1107 Mounting the MD-SAL’s NETCONF server
1108 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1109
1110 To perform this operation, just spawn a new netconf-connector as
1111 described in `Spawning new NETCONF connectors`_. Just change the ip to
1112 "127.0.0.1" port to "2830" and its name to "controller-mdsal".
1113
1114 Now the MD-SAL’s datastore can be read over RESTCONF via NETCONF by
1115 invoking:
1116
1117 GET
1118 http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=controller-mdsal/yang-ext:mount?content:nonconfig
1119
1120 .. note::
1121
1122     This might not seem very useful, since MD-SAL can be accessed
1123     directly from RESTCONF or from Application code, but the same method
1124     can be used to mount and control other OpenDaylight instances by the
1125     "master OpenDaylight".
1126
1127 NETCONF stress/performance measuring tool
1128 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1129
1130 This is basically a NETCONF client that puts NETCONF servers under heavy
1131 load of NETCONF RPCs and measures the time until a configurable amount
1132 of them is processed.
1133
1134 RESTCONF stress-performance measuring tool
1135 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1136
1137 Very similar to NETCONF stress tool with the difference of using
1138 RESTCONF protocol instead of NETCONF.
1139
1140 YANGLIB remote repository
1141 -------------------------
1142
1143 There are scenarios in NETCONF deployment, that require for a centralized
1144 YANG models repository. YANGLIB plugin provides such remote repository.
1145
1146 To start this plugin, you have to install odl-yanglib feature. Then you
1147 have to configure YANGLIB either through RESTCONF or NETCONF. We will
1148 show how to configure YANGLIB through RESTCONF.
1149
1150 YANGLIB configuration
1151 ~~~~~~~~~~~~~~~~~~~~~
1152 YANGLIB configuration works through OSGi Configuration Admin interface, in the
1153 ``org.opendaylight.netconf.yanglib`` configuration PID. There are three tuneables you can
1154 set:
1155
1156 * ``cache-folder``, which defaults to ``cache/schema``
1157 * ``binding-address``, which defaults to ``localhost``
1158 * ``binding-port``, which defaults to ``8181``
1159
1160 In order to change these settings, you can either modify the corresponding configuration
1161 file, ``etc/org.opendaylight.netconf.yanglib.cfg``, for example:
1162
1163 ::
1164     cache-folder = cache/newSchema
1165     binding-address = localhost
1166     binding-port = 8181
1167
1168 Or use Karaf CLI:
1169
1170 ::
1171     opendaylight-user@root>config:edit org.opendaylight.netconf.yanglib
1172     opendaylight-user@root>config:property-set cache-folder cache/newSchema
1173     opendaylight-user@root>config:property-set binding-address localhost
1174     opendaylight-user@root>config:property-set binding-port 8181
1175     opendaylight-user@root>config:update
1176
1177 This YANGLIB takes all YANG sources from the configured sources folder and
1178 for each generates URL in form:
1179
1180 ::
1181
1182     http://localhost:8181/yanglib/schemas/{modelName}/{revision}
1183
1184 On this URL will be hosted YANG source for particular module.
1185
1186 YANGLIB instance also writes this URL along with source identifier to
1187 ietf-netconf-yang-library/modules-state/module list.
1188
1189 Netconf-connector with YANG library as fallback
1190 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1191
1192 There is an optional configuration in netconf-connector called
1193 yang-library. You can specify YANG library to be plugged as additional
1194 source provider into the mount's schema repository. Since YANGLIB
1195 plugin is advertising provided modules through yang-library model, we
1196 can use it in mount point's configuration as YANG library.  To do this,
1197 we need to modify the configuration of netconf-connector by adding this
1198 XML
1199
1200 ::
1201
1202     <yang-library xmlns="urn:opendaylight:netconf-node-topology">
1203       <yang-library-url xmlns="urn:opendaylight:netconf-node-topology">http://localhost:8181/rests/data/ietf-yang-library:modules-state</yang-library-url>
1204       <username xmlns="urn:opendaylight:netconf-node-topology">admin</username>
1205       <password xmlns="urn:opendaylight:netconf-node-topology">admin</password>
1206     </yang-library>
1207
1208 This will register YANGLIB provided sources as a fallback schemas for
1209 particular mount point.
1210
1211 NETCONF Call Home
1212 -----------------
1213
1214 Call Home Installation
1215 ~~~~~~~~~~~~~~~~~~~~~~
1216
1217 ODL Call-Home server is installed in Karaf by installing karaf feature
1218 ``odl-netconf-callhome-ssh``. RESTCONF feature is recommended for
1219 configuring Call Home & testing its functionality.
1220
1221 ::
1222
1223   feature:install odl-netconf-callhome-ssh
1224
1225
1226 .. note::
1227
1228     In order to test Call Home functionality we recommend Netopeer or
1229     Netopeer2. See `Netopeer Call Home <https://github.com/CESNET/netopeer/wiki/CallHome>`__
1230     or `Netopeer2 <https://github.com/CESNET/netopeer2>`__ to learn how to
1231     enable call-home on Netopeer.
1232
1233 Northbound Call-Home API
1234 ~~~~~~~~~~~~~~~~~~~~~~~~
1235
1236 The northbound Call Home API is used for administering the Call-Home Server. The
1237 following describes this configuration.
1238
1239 Global Configuration
1240 ^^^^^^^^^^^^^^^^^^^^
1241
1242 .. important::
1243   The global configuration is not a part of the `RFC 8071
1244   <https://www.rfc-editor.org/rfc/rfc8071>`__ and, therefore, subject to change.
1245
1246 Configuring global credentials
1247 ''''''''''''''''''''''''''''''
1248
1249 The ODL Call-Home server allows user to configure global credentials, which will be
1250 used for devices connecting over SSH transport protocol that do not have
1251 device-specific credentials configured.
1252
1253 This is done by creating
1254 ``/odl-netconf-callhome-server:netconf-callhome-server/global/credentials``
1255 with username and passwords specified.
1256
1257 *Configuring global username & passwords to try*
1258
1259 .. code-block::
1260
1261     PUT HTTP/1.1
1262     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/global/credentials
1263     Content-Type: application/json
1264     Accept: application/json
1265
1266 .. code-block:: json
1267
1268     {
1269       "credentials":
1270       {
1271         "username": "example",
1272         "passwords": [ "first-password-to-try", "second-password-to-try" ]
1273       }
1274     }
1275
1276 Configuring to accept any ssh server key using global credentials
1277 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1278
1279 By default Netconf Call-Home Server accepts only incoming connections
1280 from allowed devices
1281 ``/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices``,
1282 if user desires to allow all incoming connections, it is possible to set
1283 ``accept-all-ssh-keys`` to ``true`` in
1284 ``/odl-netconf-callhome-server:netconf-callhome-server/global``.
1285
1286 The name of these devices in ``netconf-topology`` will be in format
1287 ``ip-address:port``. For naming devices see Device-Specific
1288 Configuration.
1289
1290 *Allowing unknown devices to connect*
1291
1292 This is a debug feature and should not be used in production. Besides being an obvious
1293 security issue, this also causes the Call-Home Server to drastically increase its output
1294 to the log.
1295
1296 .. code-block::
1297
1298     PUT HTTP/1.1
1299     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/global/accept-all-ssh-keys
1300     Content-Type: application/json
1301     Accept: application/json
1302
1303 .. code-block:: json
1304
1305     {
1306         "accept-all-ssh-keys": "true"
1307     }
1308
1309 Device-Specific Configuration
1310 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1311
1312 Netconf Call Home server supports both of the secure transports used
1313 by the Network Configuration Protocol (NETCONF) - Secure Shell (SSH),
1314 and Transport Layer Security (TLS).
1315
1316 Configure device to connect over SSH protocol
1317 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1318
1319 Netconf Call Home Server uses device provided SSH server key (host key)
1320 to identify device. The pairing of name and server key is configured in
1321 ``/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices``.
1322 This list is colloquially called a allowlist.
1323
1324 If the Call-Home Server finds the SSH host key in the allowlist, it continues
1325 to negotiate a NETCONF connection over an SSH session. If the SSH host key is
1326 not found, the connection between the Call Home server and the device is dropped
1327 immediately. In either case, the device that connects to the Call home server
1328 leaves a record of its presence in the operational store.
1329
1330 Configuring Device with Device-specific Credentials
1331 '''''''''''''''''''''''''''''''''''''''''''''''''''
1332
1333 Adding specific device to the allowed list is done by creating
1334 ``/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device={device}``
1335 with device-id and connection parameters inside the ssh-client-params container.
1336
1337 *Configuring Device with Credentials*
1338
1339 .. code-block::
1340
1341     PUT HTTP/1.1
1342     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device=example
1343     Content-Type: application/json
1344     Accept: application/json
1345
1346 .. code-block:: json
1347
1348     {
1349       "device": {
1350         "unique-id": "example",
1351         "ssh-client-params": {
1352           "credentials": {
1353             "username": "example",
1354             "passwords": [ "password" ]
1355           },
1356           "host-key": "AAAAB3NzaC1yc2EAAAADAQABAAABAQDHoH1jMjltOJnCt999uaSfc48ySutaD3ISJ9fSECe1Spdq9o9mxj0kBTTTq+2V8hPspuW75DNgN+V/rgJeoUewWwCAasRx9X4eTcRrJrwOQKzb5Fk+UKgQmenZ5uhLAefi2qXX/agFCtZi99vw+jHXZStfHm9TZCAf2zi+HIBzoVksSNJD0VvPo66EAvLn5qKWQD4AdpQQbKqXRf5/W8diPySbYdvOP2/7HFhDukW8yV/7ZtcywFUIu3gdXsrzwMnTqnATSLPPuckoi0V2jd8dQvEcu1DY+rRqmqu0tEkFBurlRZDf1yhNzq5xWY3OXcjgDGN+RxwuWQK3cRimcosH"
1357         }
1358       }
1359     }
1360
1361 Configuring Device with Global Credentials
1362 '''''''''''''''''''''''''''''''''''''''''''''''''''
1363
1364 It is possible to omit ``username`` and ``password`` for ssh-client-params,
1365 in such case values from global credentials will be used.
1366
1367 *Example of configuring device*
1368
1369 .. code-block::
1370
1371     PUT HTTP/1.1
1372     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device=example
1373     Content-Type: application/json
1374     Accept: application/json
1375
1376 .. code-block:: json
1377
1378     {
1379       "device": {
1380         "unique-id": "example",
1381         "ssh-client-params": {
1382           "host-key": "AAAAB3NzaC1yc2EAAAADAQABAAABAQDHoH1jMjltOJnCt999uaSfc48ySutaD3ISJ9fSECe1Spdq9o9mxj0kBTTTq+2V8hPspuW75DNgN+V/rgJeoUewWwCAasRx9X4eTcRrJrwOQKzb5Fk+UKgQmenZ5uhLAefi2qXX/agFCtZi99vw+jHXZStfHm9TZCAf2zi+HIBzoVksSNJD0VvPo66EAvLn5qKWQD4AdpQQbKqXRf5/W8diPySbYdvOP2/7HFhDukW8yV/7ZtcywFUIu3gdXsrzwMnTqnATSLPPuckoi0V2jd8dQvEcu1DY+rRqmqu0tEkFBurlRZDf1yhNzq5xWY3OXcjgDGN+RxwuWQK3cRimcosH"
1383         }
1384       }
1385     }
1386
1387 Deprecated configuration models for devices accessed with SSH protocol
1388 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
1389
1390 With `RFC 8071 <https://www.rfc-editor.org/rfc/rfc8071>`__ alignment and adding
1391 support for TLS transport following configuration models have been marked
1392 deprecated.
1393
1394 Configuring Device with Global Credentials
1395 '''''''''''''''''''''''''''''''''''''''''''''''''''
1396
1397 *Example of configuring device*
1398
1399 .. code-block::
1400
1401     PUT HTTP/1.1
1402     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device=example
1403     Content-Type: application/json
1404     Accept: application/json
1405
1406 .. code-block:: json
1407
1408     {
1409       "device": {
1410         "unique-id": "example",
1411         "ssh-host-key": "AAAAB3NzaC1yc2EAAAADAQABAAABAQDHoH1jMjltOJnCt999uaSfc48ySutaD3ISJ9fSECe1Spdq9o9mxj0kBTTTq+2V8hPspuW75DNgN+V/rgJeoUewWwCAasRx9X4eTcRrJrwOQKzb5Fk+UKgQmenZ5uhLAefi2qXX/agFCtZi99vw+jHXZStfHm9TZCAf2zi+HIBzoVksSNJD0VvPo66EAvLn5qKWQD4AdpQQbKqXRf5/W8diPySbYdvOP2/7HFhDukW8yV/7ZtcywFUIu3gdXsrzwMnTqnATSLPPuckoi0V2jd8dQvEcu1DY+rRqmqu0tEkFBurlRZDf1yhNzq5xWY3OXcjgDGN+RxwuWQK3cRimcosH"
1412       }
1413     }
1414
1415 Configuring Device with Device-specific Credentials
1416 '''''''''''''''''''''''''''''''''''''''''''''''''''
1417
1418 Call Home Server also allows the configuration of credentials per device basis.
1419 This is done by introducing ``credentials`` container into the
1420 device-specific configuration. Format is same as in global credentials.
1421
1422 *Configuring Device with Credentials*
1423
1424 .. code-block::
1425
1426     PUT HTTP/1.1
1427     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device=example
1428     Content-Type: application/json
1429     Accept: application/json
1430
1431 .. code-block:: json
1432
1433     {
1434       "device": {
1435         "unique-id": "example",
1436         "credentials": {
1437           "username": "example",
1438           "passwords": [ "password" ]
1439         },
1440         "ssh-host-key": "AAAAB3NzaC1yc2EAAAADAQABAAABAQDHoH1jMjltOJnCt999uaSfc48ySutaD3ISJ9fSECe1Spdq9o9mxj0kBTTTq+2V8hPspuW75DNgN+V/rgJeoUewWwCAasRx9X4eTcRrJrwOQKzb5Fk+UKgQmenZ5uhLAefi2qXX/agFCtZi99vw+jHXZStfHm9TZCAf2zi+HIBzoVksSNJD0VvPo66EAvLn5qKWQD4AdpQQbKqXRf5/W8diPySbYdvOP2/7HFhDukW8yV/7ZtcywFUIu3gdXsrzwMnTqnATSLPPuckoi0V2jd8dQvEcu1DY+rRqmqu0tEkFBurlRZDf1yhNzq5xWY3OXcjgDGN+RxwuWQK3cRimcosH"
1441       }
1442     }
1443
1444 Configure device to connect over TLS protocol
1445 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
1446
1447 Netconf Call Home Server allows devices to use TLS transport protocol to
1448 establish a connection towards the NETCONF device. This communication
1449 requires proper setup to make two-way TLS authentication possible for client
1450 and server.
1451
1452 The initial step is to configure certificates and keys for two-way TLS by
1453 storing them within the netconf-keystore.
1454
1455 *Adding a client private key credential to the netconf-keystore*
1456
1457 .. code-block::
1458
1459     POST HTTP/1.1
1460     /rests/operations/netconf-keystore:add-keystore-entry
1461     Content-Type: application/json
1462     Accept: application/json
1463
1464 .. code-block:: json
1465
1466   {
1467     "input": {
1468       "key-credential": [
1469         {
1470           "key-id": "example-client-key-id",
1471           "private-key": "base64encoded-private-key",
1472           "passphrase": "passphrase"
1473         }
1474       ]
1475     }
1476   }
1477
1478 *Associate a private key with a client and CA certificates chain*
1479
1480 .. code-block::
1481
1482     POST HTTP/1.1
1483     /rests/operations/netconf-keystore:add-private-key
1484     Content-Type: application/json
1485     Accept: application/json
1486
1487 .. code-block:: json
1488
1489   {
1490     "input": {
1491       "private-key": [
1492         {
1493           "name": "example-client-key-id",
1494           "data": "key-data",
1495           "certificate-chain": [
1496             "certificate-data"
1497           ]
1498         }
1499       ]
1500     }
1501   }
1502
1503 *Add a list of trusted CA and server certificates*
1504
1505 .. code-block::
1506
1507     POST HTTP/1.1
1508     /rests/operations/netconf-keystore:add-trusted-certificate
1509     Content-Type: application/json
1510     Accept: application/json
1511
1512 .. code-block:: json
1513
1514   {
1515     "input": {
1516       "trusted-certificate": [
1517         {
1518           "name": "example-ca-certificate",
1519           "certificate": "ca-certificate-data"
1520         },
1521         {
1522           "name": "example-server-certificate",
1523           "certificate": "server-certificate-data"
1524         }
1525       ]
1526     }
1527   }
1528
1529 In a second step, it is required to create an allowed device associated with
1530 a server certificate and client key. The server certificate will be used to
1531 identify and pin the NETCONF device during SSL handshake and should be unique
1532 among the allowed devices.
1533
1534 *Add device configuration for TLS protocol to allowed devices list*
1535
1536 .. code-block::
1537
1538     PUT HTTP/1.1
1539     /rests/data/odl-netconf-callhome-server:netconf-callhome-server/allowed-devices/device=example-device
1540     Content-Type: application/json
1541     Accept: application/json
1542
1543 .. code-block:: json
1544
1545   {
1546     "device": {
1547       "unique-id": "example-device",
1548       "tls-client-params": {
1549         "key-id": "example-client-key-id",
1550         "certificate-id": "example-server-certificate"
1551       }
1552     }
1553   }
1554
1555 Operational Status
1556 ^^^^^^^^^^^^^^^^^^
1557
1558 Once an entry is made on the config side of "allowed-devices", the Call-Home Server will
1559 populate a corresponding operational device that is the same as the config device but
1560 has an additional status. By default, this status is *DISCONNECTED*. Once a device calls
1561 home, this status will change to one of:
1562
1563 *CONNECTED* — The device is currently connected and the NETCONF mount is available for network
1564 management.
1565
1566 *FAILED_AUTH_FAILURE* — The last attempted connection was unsuccessful because the Call-Home
1567 Server was unable to provide the acceptable credentials of the device. The device is also
1568 disconnected and not available for network management.
1569
1570 *FAILED_NOT_ALLOWED* — The last attempted connection was unsuccessful because the device was
1571 not recognized as an acceptable device. The device is also disconnected and not available for
1572 network management.
1573
1574 *FAILED* — The last attempted connection was unsuccessful for a reason other than not
1575 allowed to connect or incorrect client credentials. The device is also disconnected and not
1576 available for network management.
1577
1578 *DISCONNECTED* — The device is currently disconnected.
1579
1580 Rogue Devices
1581 '''''''''''''
1582
1583 Devices that are not on the allowlist might try to connect to the Call-Home Server. In
1584 these cases, the server will keep a record by instantiating an operational device. There
1585 will be no corresponding config device for these rogues. They can be identified readily
1586 because their device id, rather than being user-supplied, will be of the form
1587 "address:port". Note that if a device calls back multiple times, there will only be
1588 a single operatinal entry (even if the port changes); these devices are recognized by
1589 their unique host key.
1590
1591 Southbound Call-Home API
1592 ~~~~~~~~~~~~~~~~~~~~~~~~
1593
1594 The Call-Home Server listens for incoming TCP connections and assumes that the other side of
1595 the connection is a device calling home via a NETCONF connection with SSH for
1596 management. The server uses port 4334 by default and this can be configured via a
1597 blueprint configuration file.
1598
1599 The device **must** initiate the connection and the server will not try to re-establish the
1600 connection in case of a drop. By requirement, the server cannot assume it has connectivity
1601 to the device due to NAT or firewalls among others.
1602
1603 Reading data with selected fields
1604 ---------------------------------
1605
1606 Overview
1607 ~~~~~~~~
1608
1609 If user would like to read only selected fields from a NETCONF device, it is possible to use
1610 the fields query parameter that is described by RFC-8040. RESTCONF parses content of query
1611 parameter into format that is accepted by NETCONF subtree filtering - filtering of data is done
1612 on NETCONF server, not on NETCONF client side. This approach optimizes network traffic load,
1613 because data in which user doesn't have interest, is not transferred over network.
1614
1615 Next advantages:
1616
1617 * using single RESTCONF request and single NETCONF RPC for reading multiple subtrees
1618 * possibility to read only selected fields under list node across multiple hierarchies
1619   (it cannot be done without proper selection API)
1620
1621 .. note::
1622
1623   More information about fields query parameter: `RFC 8071 <https://www.rfc-editor.org/rfc/rfc8040#section-4.8.3>`__
1624
1625 Preparation of data
1626 ~~~~~~~~~~~~~~~~~~~
1627
1628 For demonstration, we will define next YANG model:
1629
1630 ::
1631
1632     module test-module {
1633         yang-version 1.1;
1634         namespace "urn:opendaylight:test-module";
1635         prefix "tm";
1636         revision "2023-02-16";
1637
1638         container root {
1639             container simple-root {
1640                 leaf leaf-a {
1641                     type string;
1642                 }
1643                 leaf leaf-b {
1644                     type string;
1645                 }
1646                 leaf-list ll {
1647                     type string;
1648                 }
1649                 container nested {
1650                     leaf sample-x {
1651                         type boolean;
1652                     }
1653                     leaf sample-y {
1654                         type boolean;
1655                     }
1656                 }
1657             }
1658
1659             container list-root {
1660                 leaf branch-ab {
1661                     type int32;
1662                 }
1663                 list top-list {
1664                     key "key-1 key-2";
1665                     ordered-by user;
1666                     leaf key-1 {
1667                         type string;
1668                     }
1669                     leaf key-2 {
1670                         type string;
1671                     }
1672                     container next-data {
1673                         leaf switch-1 {
1674                             type empty;
1675                         }
1676                         leaf switch-2 {
1677                             type empty;
1678                         }
1679                     }
1680                     list nested-list {
1681                         key "identifier";
1682                         leaf identifier {
1683                             type string;
1684                         }
1685                         leaf foo {
1686                             type int32;
1687                         }
1688                     }
1689                 }
1690             }
1691         }
1692     }
1693
1694 Follow the :doc:`testtool` instructions to save this schema and run it with testtool.
1695
1696 Mounting NETCONF device that runs on NETCONF testtool:
1697
1698 .. code-block:: bash
1699
1700   curl --location --request PUT 'http://127.0.0.1:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=testtool' \
1701   --header 'Authorization: Basic YWRtaW46YWRtaW4=' \
1702   --header 'Content-Type: application/json' \
1703   --data-raw '{
1704       "node": [
1705           {
1706               "node-id": "testtool",
1707               "netconf-node-topology:host": "127.0.0.1",
1708               "netconf-node-topology:port": 17830,
1709               "netconf-node-topology:keepalive-delay": 100,
1710               "netconf-node-topology:tcp-only": false,
1711               "netconf-node-topology:login-password-unencrypted": {
1712                   "netconf-node-topology:username": "admin",
1713                   "netconf-node-topology:password": "admin"
1714               },
1715           }
1716       ]
1717   }'
1718
1719 Setting initial configuration on NETCONF device:
1720
1721 .. code-block:: bash
1722
1723   curl --location --request PUT 'http://127.0.0.1:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=testtool/yang-ext:mount/test-module:root' \
1724   --header 'Authorization: Basic YWRtaW46YWRtaW4=' \
1725   --header 'Content-Type: application/json' \
1726   --data-raw '{
1727       "root": {
1728           "simple-root": {
1729               "leaf-a": "asddhg",
1730               "leaf-b": "ffffff",
1731               "ll": [
1732                   "str1",
1733                   "str2",
1734                   "str3"
1735               ],
1736               "nested": {
1737                   "sample-x": true,
1738                   "sample-y": false
1739               }
1740           },
1741           "list-root": {
1742               "branch-ab": 5,
1743               "top-list": [
1744                   {
1745                       "key-1": "ka",
1746                       "key-2": "kb",
1747                       "next-data": {
1748                           "switch-1": [
1749                               null
1750                           ],
1751                           "switch-2": [
1752                               null
1753                           ]
1754                       },
1755                       "nested-list": [
1756                           {
1757                               "identifier": "f1",
1758                               "foo": 1
1759                           },
1760                           {
1761                               "identifier": "f2",
1762                               "foo": 10
1763                           },
1764                           {
1765                               "identifier": "f3",
1766                               "foo": 20
1767                           }
1768                       ]
1769                   },
1770                   {
1771                       "key-1": "kb",
1772                       "key-2": "ka",
1773                       "next-data": {
1774                           "switch-1": [
1775                               null
1776                           ]
1777                       },
1778                       "nested-list": [
1779                           {
1780                               "identifier": "e1",
1781                               "foo": 1
1782                           },
1783                           {
1784                               "identifier": "e2",
1785                               "foo": 2
1786                           },
1787                           {
1788                               "identifier": "e3",
1789                               "foo": 3
1790                           }
1791                       ]
1792                   },
1793                   {
1794                       "key-1": "kc",
1795                       "key-2": "ke",
1796                       "next-data": {
1797                           "switch-2": [
1798                               null
1799                           ]
1800                       },
1801                       "nested-list": [
1802                           {
1803                               "identifier": "q1",
1804                               "foo": 13
1805                           },
1806                           {
1807                               "identifier": "q2",
1808                               "foo": 14
1809                           },
1810                           {
1811                               "identifier": "q3",
1812                               "foo": 15
1813                           }
1814                       ]
1815                   }
1816               ]
1817           }
1818       }
1819   }'
1820
1821 Examples
1822 --------
1823
1824 1. Reading whole leaf-list 'll' and leaf 'nested/sample-x' under 'simple-root' container.
1825
1826 RESTCONF request:
1827
1828 .. code-block:: bash
1829
1830     curl --location --request GET 'http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=testtool/yang-ext:mount/test-module:root/simple-root?content=config&fields=ll;nested/sample-x' \
1831     --header 'Authorization: Basic YWRtaW46YWRtaW4=' \
1832     --header 'Cookie: JSESSIONID=node01h4w82eorc1k61866b71qjgj503.node0'
1833
1834 Generated NETCONF RPC request:
1835
1836 .. code-block:: xml
1837
1838     <rpc message-id="m-18" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
1839         <get-config>
1840             <source>
1841                 <running/>
1842             </source>
1843             <filter xmlns:ns0="urn:ietf:params:xml:ns:netconf:base:1.0" ns0:type="subtree">
1844                 <root xmlns="urn:ietf:params:xml:ns:yang:test-model">
1845                     <simple-root>
1846                         <ll/>
1847                         <nested>
1848                             <sample-x/>
1849                         </nested>
1850                     </simple-root>
1851                 </root>
1852             </filter>
1853         </get-config>
1854     </rpc>
1855
1856 .. note::
1857
1858     Using fields query parameter it is also possible to read whole leaf-list or list without
1859     necessity to specify value / key predicate (without reading parent entity). Such scenario
1860     is not permitted in RFC-8040 paths alone - fields query parameter can be used as
1861     workaround for this case.
1862
1863 RESTCONF response:
1864
1865 .. code-block:: json
1866
1867     {
1868         "test-module:simple-root": {
1869             "ll": [
1870                 "str3",
1871                 "str1",
1872                 "str2"
1873             ],
1874             "nested": {
1875                 "sample-x": true
1876             }
1877         }
1878     }
1879
1880 2. Reading all identifiers of 'nested-list' under all elements of 'top-list'.
1881
1882 RESTCONF request:
1883
1884 .. code-block:: bash
1885
1886     curl --location --request GET 'http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=testtool/yang-ext:mount/test-module:root/list-root?content=config&fields=top-list(nested-list/identifier)' \
1887     --header 'Authorization: Basic YWRtaW46YWRtaW4=' \
1888     --header 'Cookie: JSESSIONID=node01h4w82eorc1k61866b71qjgj503.node0'
1889
1890 Generated NETCONF RPC request:
1891
1892 .. code-block:: xml
1893
1894     <rpc message-id="m-27" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
1895         <get-config>
1896             <source>
1897                 <running/>
1898             </source>
1899             <filter xmlns:ns0="urn:ietf:params:xml:ns:netconf:base:1.0" ns0:type="subtree">
1900                 <root xmlns="urn:ietf:params:xml:ns:yang:test-model">
1901                     <list-root>
1902                         <top-list>
1903                             <nested-list>
1904                                 <identifier/>
1905                             </nested-list>
1906                             <key-1/>
1907                             <key-2/>
1908                         </top-list>
1909                     </list-root>
1910                 </root>
1911             </filter>
1912         </get-config>
1913     </rpc>
1914
1915 .. note::
1916
1917     NETCONF client automatically fetches values of list keys since they are required for correct
1918     deserialization of NETCONF response and at the end serialization of response to RESTCONF
1919     response (JSON/XML).
1920
1921 RESTCONF response:
1922
1923 .. code-block:: json
1924
1925     {
1926         "test-module:list-root": {
1927             "top-list": [
1928                 {
1929                     "key-1": "ka",
1930                     "key-2": "kb",
1931                     "nested-list": [
1932                         {
1933                             "identifier": "f3"
1934                         },
1935                         {
1936                             "identifier": "f2"
1937                         },
1938                         {
1939                             "identifier": "f1"
1940                         }
1941                     ]
1942                 },
1943                 {
1944                     "key-1": "kb",
1945                     "key-2": "ka",
1946                     "nested-list": [
1947                         {
1948                             "identifier": "e3"
1949                         },
1950                         {
1951                             "identifier": "e2"
1952                         },
1953                         {
1954                             "identifier": "e1"
1955                         }
1956                     ]
1957                 },
1958                 {
1959                     "key-1": "kc",
1960                     "key-2": "ke",
1961                     "nested-list": [
1962                         {
1963                             "identifier": "q3"
1964                         },
1965                         {
1966                             "identifier": "q2"
1967                         },
1968                         {
1969                             "identifier": "q1"
1970                         }
1971                     ]
1972                 }
1973             ]
1974         }
1975     }
1976
1977 3. Reading value of leaf 'branch-ab' and all values of leaves 'switch-1' that are placed
1978    under 'top-list' list elements.
1979
1980 RESTCONF request:
1981
1982 .. code-block:: bash
1983
1984     curl --location --request GET 'http://localhost:8181/rests/data/network-topology:network-topology/topology=topology-netconf/node=testtool/yang-ext:mount/test-module:root/list-root?content=config&fields=branch-ab;top-list/next-data/switch-1' \
1985     --header 'Authorization: Basic YWRtaW46YWRtaW4=' \
1986     --header 'Cookie: JSESSIONID=node01jx6o5thwae9t1ft7c2zau5zbz4.node0'
1987
1988 Generated NETCONF RPC request:
1989
1990 .. code-block:: xml
1991
1992     <rpc message-id="m-42" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
1993         <get-config>
1994             <source>
1995                 <running/>
1996             </source>
1997             <filter xmlns:ns0="urn:ietf:params:xml:ns:netconf:base:1.0" ns0:type="subtree">
1998                 <root xmlns="urn:ietf:params:xml:ns:yang:test-model">
1999                     <list-root>
2000                         <branch-ab/>
2001                         <top-list>
2002                             <next-data>
2003                                 <switch-1/>
2004                             </next-data>
2005                             <key-1/>
2006                             <key-2/>
2007                         </top-list>
2008                     </list-root>
2009                 </root>
2010             </filter>
2011         </get-config>
2012     </rpc>
2013
2014 RESTCONF response:
2015
2016 .. code-block:: json
2017
2018     {
2019         "test-module:list-root": {
2020             "branch-ab": 5,
2021             "top-list": [
2022                 {
2023                     "key-1": "ka",
2024                     "key-2": "kb",
2025                     "next-data": {
2026                         "switch-1": [
2027                             null
2028                         ]
2029                     }
2030                 },
2031                 {
2032                     "key-1": "kb",
2033                     "key-2": "ka",
2034                     "next-data": {
2035                         "switch-1": [
2036                             null
2037                         ]
2038                     }
2039                 },
2040                 {
2041                     "key-1": "kc",
2042                     "key-2": "ke"
2043                 }
2044             ]
2045         }
2046     }
2047
2048 RESTCONF OpenAPI
2049 ----------------
2050
2051 Overview
2052 ~~~~~~~~
2053
2054 The OpenAPI provides full API for configurational data which can be edited (by POST, PUT, PATCH and DELETE).
2055 For operational data we only provide GET API. For the majority of requests you can see only config data in examples.
2056 That’s because we can show only one example per request. The exception when you can see operational data in an
2057 example is when data are representing an operational (config false) container with no config data in it.
2058
2059
2060 Using the OpenAPI Explorer through HTTP
2061 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2062
2063 1. Install OpenApi into Karaf by installing karaf feature:
2064
2065 ::
2066
2067     $ feature:install odl-restconf-openapi
2068
2069 2.  Navigate to OpenAPI in your web browser which is available at URLs:
2070
2071 -  http://localhost:8181/openapi/explorer/index.html for general overview
2072
2073 -  http://localhost:8181/openapi/api/v3/single for JSON data
2074
2075 .. note::
2076
2077     In the URL links for OpenAPI, change *localhost* to the IP/Host name of your actual server.
2078
2079 3.  Enter the username and password.
2080     By default the credentials are  *admin/admin*.
2081
2082 4.  Select any model to try out.
2083
2084 5.  Select any available request to try out.
2085
2086 6.  Click on the **Try it out** button.
2087
2088 7.  Provide any required parameters or edit request body.
2089
2090 8.  Click the **Execute** button.
2091
2092 9.  You can see responses to the given request.
2093
2094
2095 OpenAPI Explorer can also be used for connected device. How to connect a device can be found :ref:`here <netconf-connector>`.
2096
2097 OpenAPI URLs in that case would look like this:
2098
2099 -  `http://localhost:8181/openapi/explorer/index.html?urls.primaryName=17830-sim-device resources - RestConf RFC 8040 <http://localhost:8181/openapi/explorer/index.html?urls.primaryName=17830-sim-device%20resources%20-%20RestConf%20RFC%208040>`_ for device overview
2100
2101 -  http://localhost:8181/openapi/api/v3/mounts/1 for JSON data
2102
2103 -  `http://localhost:8181/openapi/api/v3/mounts/1/toaster(2009-11-20) <http://localhost:8181/openapi/api/v3/mounts/1/toaster(2009-11-20)>`__ JSON data for given model
2104
2105 .. note::
2106
2107     The URL links for OpenAPI are made for device with name *17830-sim-device* and model toaster
2108     with *2009-11-20* revision and need to be changed accordingly to connected device.