module network-topology-pcep {
    // vi: set et smarttab sw=4 tabstop=4:
    yang-version 1;
    namespace "urn:opendaylight:params:xml:ns:yang:topology:pcep";
    prefix "pn";

    import ietf-inet-types { prefix inet; revision-date 2013-07-15; }
    import network-topology { prefix nt; revision-date 2013-10-21; }
    import odl-network-topology { prefix ont; revision-date 2014-01-13; }
    import pcep-types { prefix pcep; revision-date 2018-11-09; }
    import rsvp { prefix rsvp; revision-date 2015-08-20; }
    import pcep-config { prefix pdc; }

    organization "Cisco Systems, Inc.";
    contact "Robert Varga <rovarga@cisco.com>";

    description
        "This module contains the PCEP extensions to base topology model. It
        exposes the LSPs for which a particular node is the head end.

        This module exposes three programming instructions,add-lsp,
        remove-lsp and update-lsp, which map to actively-stateful PCEP
        operations using PCInitiate and PCUpd messages to initiate,
        destroy and udpate LSP configuration. The lifecycle of these
        instructions follows RFC8281 and RFC8231, completing execution once the
        head-end router has acknowledged operation success. Should the router
        become disconnected, the instruction resolve to Cancelled if the
        message has not been sent into the TCP socket, or Failed it they have.

        Copyright (c)2013 Cisco Systems, Inc. All rights reserved.

        This program and the accompanying materials are made available
        under the terms of the Eclipse Public License v1.0 which
        accompanies this distribution, and is available at
        http://www.eclipse.org/legal/epl-v10.html";

    revision 2022-07-30 {
        description "Integrated PCEP session configuration";
    }

    revision 2020-01-20 {
        description "Update to use -no-zone-adresses";
    }

    revision "2018-11-09" {
        description
            "P2MP extension.";
        reference "RFC8306";
    }

    revision 2017-10-25 {
        description "Add release-connection rpc";
    }

    revision "2013-10-24" {
        description
            "Initial revision.";
        reference "";
    }

    typedef pcc-sync-state {
        type enumeration {
            enum initial-resync {
                description
                    "Initial state resynchronization is being performed.";
            }
            enum incremental-sync {
                description
                    "Incremental state resynchronization is being performed.";
            }
            enum triggered-initial-sync {
                description
                     "Triggered initial state resynchronization is being performed.";
            }
            enum pcep-triggered-resync {
                description
                    "Pcep triggered state resynchronization is being performed.";
            }
            enum synchronized {
                description
                    "State synchronization has been achieved.";
            }
        }
    }

    augment "/nt:network-topology/nt:topology/nt:topology-types" {
        container topology-pcep {
            presence "indicates a PCEP-aware topology";

            leaf ted-name {
                type leafref {
                    path /nt:network-topology/nt:topology/nt:topology-id;
                }
            }

            uses pdc:pcep-config;
        }
    }

    grouping pcep-client-attributes {
        description "Data present in a node which is a PCEP client (PCC).";

        container path-computation-client {
            description
                "PCC-related run-time information. This container is only
                present when the node is connected through PCEP in a PCC
                role.";
            config false;

            leaf ip-address {
                description
                    "IP address which the node used to connected to the PCE.
                    There are no guarantees as to reachability of the address,
                    nor its relationship to other control, management, or
                    data plane addresses.";

                type inet:ip-address-no-zone;
            }

            container stateful-tlv {

            }

            leaf state-sync {
                type pcc-sync-state;
                when "../stateful-tlv";
            }

            list reported-lsp {
                leaf name {
                    type string;
                }
                key name;

                list path {
                    leaf lsp-id {
                        type rsvp:lsp-id;
                        mandatory true;
                    }
                    key lsp-id;

                    uses pcep:path-definition;
                }
                uses lsp-metadata;
            }
        }
    }

    augment "/nt:network-topology/nt:topology/nt:node" {
        when "../../nt:topology-types/pn:topology-pcep";

        uses pcep-client-attributes;
        uses pdc:pcep-node-config;
    }

    typedef failure-type {
        description
            "Enumeration of all the distinct failure modes that can
            happen while servicing a request towards the PCC.";

        type enumeration {
            enum unsent {
                description
                    "The request failed before it was sent to the PCC.
                    PCC's state is guaranteed not to reflect state
                    transition implied by the request. This typically
                    happens if the request is syntactically invalid,
                    the target PCC is not connected or disconnects
                    while the request is enqueued.";
            }
            enum no-ack {
                description
                    "The request has been sent to the PCC, but either the
                    session went down before we have received confirmation
                    of the request being received by the PCC, or the request
                    timed-out waiting for response from PCC. PCC's state is
                    unknown -- the request may or may not be reflected
                    in its internal state. The caller should not make
                    any hard assumptions about PCC state until it reconnects
                    and state synchronization completes.";
            }
            enum failed {
                description
                    "The request has been seen by the PCC, where it failed
                    for some external reason. The caller can assume the
                    state transition has not taken place, but is advised
                    to examine the attached error list to gain a deeper
                    understanding of the failure cause.";
            }
        }
    }

    grouping node-id {
        leaf node {
            type nt:node-ref;
            mandatory true;
        }
    }

    grouping lsp-id {
        uses node-id;

        leaf name {
            type string;
            mandatory true;
        }
    }

    grouping operation-result {
        leaf failure {
            type failure-type;
        }

        list error {
            when "../failure = failed";
            uses pcep:pcep-error-object;
        }
    }

    grouping lsp-metadata {

        container metadata {
            description
                "Container for external metadata attached to the LSP. Contents of this container
                are not propagated onto the router itself, so it is persisted only while the LSP
                is present.";
        }
    }

    grouping add-lsp-args {
        uses lsp-id;

        container arguments {

            uses pcep:endpoints-object;

            uses pcep:path-definition;

            uses lsp-metadata;
        }
    }

    rpc add-lsp {
        input {
            uses ont:network-topology-reference;
            uses add-lsp-args;
        }
        output {
            uses operation-result;
        }
    }

    grouping remove-lsp-args {
        uses lsp-id;
    }

    rpc remove-lsp {
        input {
            uses ont:network-topology-reference;
            uses remove-lsp-args;
        }
        output {
            uses operation-result;
        }
    }

    grouping update-lsp-args {
        uses lsp-id;

        container arguments {

            uses pcep:path-definition;

            uses lsp-metadata;
        }
    }

    rpc update-lsp {
        input {
            uses ont:network-topology-reference;
            uses update-lsp-args;
        }
        output {
            uses operation-result;
        }
    }

    grouping ensure-lsp-operational-args {
        uses lsp-id;

        container arguments {

        }
    }

    rpc ensure-lsp-operational {
        description
            "Ensure that the target LSP is provisioned and has specified
            operational status.";

        input {
            uses ont:network-topology-reference;
            uses ensure-lsp-operational-args;
        }
        output {
            uses operation-result;
        }
    }

    grouping trigger-sync-args {
        uses lsp-id {
          refine name {
            mandatory false;
          }
        }
    }

    rpc trigger-sync {
        input {
            uses ont:network-topology-reference;
            uses trigger-sync-args;
        }
        output {
            uses operation-result;
        }
    }

    rpc tear-down-session {
        description "Closes the session between PCE and PCC.";
        input {
            uses ont:network-topology-reference;
            uses node-id;
        }
    }
}