def addEndpointsCoupleAndFlowrules(self, endpoint_id, flowrule_priority=10):
     endpoint_1 = EndPoint(_id = str(endpoint_id)+"_1")
     endpoint_2 = EndPoint(_id = str(endpoint_id)+"_2")
     flowrule_1 = FlowRule()                  
     flowrule_1.id = endpoint_1.id
     flowrule_1.priority = flowrule_priority
     flowrule_1.match = Match(port_in="endpoint:"+endpoint_1.id)
     flowrule_1.actions.append(Action(output="endpoint:"+endpoint_2.id))
     flowrule_2 = FlowRule()                  
     flowrule_2.id = endpoint_2.id
     flowrule_2.priority = flowrule_priority
     flowrule_2.match = Match(port_in="endpoint:"+endpoint_2.id)
     flowrule_2.actions.append(Action(output="endpoint:"+endpoint_1.id))
     self.nffg.addEndPoint(endpoint_1)
     self.nffg.addEndPoint(endpoint_2)
     self.nffg.addFlowRule(flowrule_1)
     self.nffg.addFlowRule(flowrule_2)
    def getNFFG(self, session_id):
        session = get_session()
        session_ref = session.query(GraphSessionModel).filter_by(session_id=session_id).one()
        
        # [ NF-FG ]
        nffg = NF_FG()
        nffg.id = session_ref.graph_id
        nffg.name = session_ref.graph_name
        nffg.description = session_ref.description
        
        
        # [ ENDPOINTs ]
        end_points_ref = session.query(EndpointModel).filter_by(session_id=session_id).all()
        for end_point_ref in end_points_ref:
            
            # Add endpoint to NFFG
            end_point = EndPoint(_id=end_point_ref.graph_endpoint_id, name=end_point_ref.name, _type=end_point_ref.type, 
                                 db_id=end_point_ref.id)
            nffg.addEndPoint(end_point)
            
            # End_point resource
            end_point_resorces_ref = session.query(EndpointResourceModel).filter_by(endpoint_id=end_point_ref.id).all()
            for end_point_resorce_ref in end_point_resorces_ref:
                if end_point_resorce_ref.resource_type == 'port':
                    try:
                        port_ref = session.query(PortModel).filter_by(id=end_point_resorce_ref.resource_id).one()
                    except NoResultFound:
                        port_ref = None
                        logging.debug("Port not found for endpoint "+end_point_ref.graph_endpoint_id)
                    if port_ref is not None:
                        end_point.switch_id = port_ref.switch_id
                        end_point.interface = port_ref.graph_port_id
                        end_point.vlan_id = port_ref.vlan_id


        # [ FLOW RULEs ]
        flow_rules_ref = session.query(FlowRuleModel).filter_by(session_id=session_id).all()
        for flow_rule_ref in flow_rules_ref:
            if flow_rule_ref.type is not None: # None or 'external'
                continue
            
            # Add flow rule to NFFG
            flow_rule = FlowRule(_id=flow_rule_ref.graph_flow_rule_id, internal_id=flow_rule_ref.internal_id, 
                                 priority=int(flow_rule_ref.priority), description=flow_rule_ref.description, 
                                 db_id=flow_rule_ref.id)
            nffg.addFlowRule(flow_rule)
            
            
            # [ MATCH ]
            try:
                match_ref = session.query(MatchModel).filter_by(flow_rule_id=flow_rule_ref.id).one()
            except NoResultFound:
                match_ref = None
                logging.debug("Found flowrule without a match")

            if match_ref is not None:
                # Retrieve endpoint data
                port_in = None
                if match_ref.port_in_type == 'endpoint':
                    end_point_ref = session.query(EndpointModel).filter_by(id=match_ref.port_in).first()
                    port_in = 'endpoint:'+end_point_ref.graph_endpoint_id
                
                # Add match to this flow rule
                match = Match(port_in=port_in, ether_type=match_ref.ether_type, vlan_id=match_ref.vlan_id,
                              vlan_priority=match_ref.vlan_priority, source_mac=match_ref.source_mac,
                              dest_mac=match_ref.dest_mac, source_ip=match_ref.source_ip, dest_ip=match_ref.dest_ip,
                              tos_bits=match_ref.tos_bits, source_port=match_ref.source_port, dest_port=match_ref.dest_port,
                              protocol=match_ref.protocol, db_id=match_ref.id)
                flow_rule.match = match
                

            # [ ACTIONs ]
            actions_ref = session.query(ActionModel).filter_by(flow_rule_id=flow_rule_ref.id).all()
            if len(actions_ref)==0:
                logging.debug("Found flowrule without actions")
                
            for action_ref in actions_ref:
                output_to_port = None
                # Retrieve endpoint data
                if action_ref.output_type == 'endpoint':
                    end_point_ref = session.query(EndpointModel).filter_by(id = action_ref.output_to_port).first()
                    output_to_port = action_ref.output_type+':'+end_point_ref.graph_endpoint_id
                
                # Add action to this flow rule
                action = Action(output=output_to_port, controller=action_ref.output_to_controller, drop=action_ref._drop, 
                                set_vlan_id=action_ref.set_vlan_id, set_vlan_priority=action_ref.set_vlan_priority, 
                                push_vlan=action_ref.push_vlan, pop_vlan=action_ref.pop_vlan, 
                                set_ethernet_src_address=action_ref.set_ethernet_src_address, 
                                set_ethernet_dst_address=action_ref.set_ethernet_dst_address, 
                                set_ip_src_address=action_ref.set_ip_src_address, set_ip_dst_address=action_ref.set_ip_dst_address, 
                                set_ip_tos=action_ref.set_ip_tos, set_l4_src_port=action_ref.set_l4_src_port, 
                                set_l4_dst_port=action_ref.set_l4_dst_port, output_to_queue=action_ref.output_to_queue,
                                db_id=action_ref.id)
                flow_rule.actions.append(action)
        
        return nffg