module openconfig-platform-healthz {

    yang-version 1;

    namespace
      "http://openconfig.net/yang/platform/healthz";

    prefix oc-platform-healthz;

    import openconfig-extensions {
      prefix oc-ext;
    }
    import openconfig-types {
      prefix oc-types;
    }
    import openconfig-platform {
      prefix oc-platform;
    }

    organization "OpenConfig working group";

    contact
      "OpenConfig working group
    www.openconfig.net";

    description
      "This model defines health-related variables for components
     within the openconfig-platform model (which defines the
     the /components hierarchy). It is designed to be used in
     conjunction with the gNOI Healthz service (see
     https://github.com/openconfig/gnoi/blob/main/healthz/README.md).

     The health variables included in this model are streamed via
     telemetry interfaces, where gNOI.Healthz is used to retrieve
     further diagnostic and debugging informaton from a network
     device.";

    revision "2023-04-11" {
      description
        "Clarification for healthz state transition and unhealthy-count leaf";
      reference
        "0.1.1";

    }

    revision "2023-01-23" {
      description
        "Initial healthz variable revision";
      reference
        "0.1.0";

    }

    oc-ext:openconfig-version "0.1.1";

    grouping platform-health-top {
      description
        "Grouping containing health-related parameters.";
      container healthz {
        description
          "The health of the component. The paramaters within this
        container indicate the status of the component beyond whether
        it is operationally up or down. When a signal is received
        that a component is in an unhealthy state the gNOI.Healthz
        service can be used to retrieve further diagnostic information
        relating to the component.

        The contents of this directory relate only to the specific
        component that it is associated with. In the case that child
        components become unhealthy and this causes a parent component
        to be unhealthy, the new unhealthy status should be reported at
        both components, such that an interested system can take the
        relevant actions (e.g., retrieve the Healthz output, or
        apply mitigation actions).";
        reference
          "https://github.com/openconfig/gnoi/tree/main/healthz";

        container state {
          config false;
          description
            "Operational state parameters relating to component health.";
          uses platform-health-state;
        }  // container state
      }  // container healthz
    }  // grouping platform-health-top

    grouping platform-health-state {
      description
        "Operational state parameters relating to a platform component's
      health.";
      leaf status {
        oc-ext:telemetry-on-change;
        type enumeration {
          enum "UNSPECIFIED" {
            value 0;
            description
              "The component's health status has not yet been checked
            by the system.";
          }
          enum "HEALTHY" {
            value 1;
            description
              "The component is in a HEALTHY state, and is operating
            within the expected parameters.";
          }
          enum "UNHEALTHY" {
            value 2;
            description
              "The component is in a unhealthy state, it is not
            performing the function expected of it.";
          }
        }
        description
          "The status of the component, indicating its current health.";
      }

      leaf last-unhealthy {
        oc-ext:telemetry-on-change;
        type oc-types:timeticks64;
        description
          "The time at which the component as last observed to be unhealthy
        represented as nanoseconds since the Unix epoch. Unhealthy is defined
        as the component being in a state other than HEALTHY.";
      }

      leaf unhealthy-count {
        oc-ext:telemetry-on-change;
        type uint64;
        description
          "The number of status checks that have determined this component
        to be in an unhealthy state. This counter should be incremented
        when the component transitions from the HEALTHY to any other
        state such that the value reflects the number of times the
        component has become unhealthy.";
      }
    }  // grouping platform-health-state

    augment /oc-platform:components/oc-platform:component {
      description
        "Augment healthz information into the /components/component hierarchy.";
      uses platform-health-top;
    }
  }  // module openconfig-platform-healthz