module topology {

  namespace "urn:topology";

  prefix "topology";

  organization
    "CTTC";

  contact
    "ricard.vilalta@cttc.es";

  description
    "Basic example of network topology";

  revision "2018-08-24" {
    description "Basic example of network topology";
    reference "";
  }

  /**
   * Typedefs / identities
   */
  typedef layer-protocol-name {
     type enumeration {
         enum "ETH";
         enum "OPTICAL";
     }
   }
   
   
  /**
   * Groupings
   */
  grouping port {
    leaf port-id {
      type string;
    }
    leaf layer-protocol-name {
      type layer-protocol-name;
    }

  }

  grouping node {
    leaf node-id {
      type string;
    }
    list port {
       key "port-id";
       uses port;
    }
  }

  grouping link {
    leaf link-id {
      type string;
    }
    leaf source-node {
      type leafref {
        path "/topology/node/node-id";
      }
    }
    leaf target-node {
      type leafref {
        path "/topology/node/node-id";
      }    
    }
    leaf source-port {
      type leafref {
        path "/topology/node/port/port-id";
      }    
    }
    leaf target-port {
      type leafref {
        path "/topology/node/port/port-id";
      }    
    }
  }

  grouping topology {
      list node {
        key "node-id";
        uses node;
      }
      list link {
        key "link-id";
        uses link;
      }  
  }

  /**
   * Container/lists
   */
  container topology {
    uses topology;
  }

}