[小 迪 导读]：OPCSoftware is the most widely used software in the field of industrial automation,It is deeply loved by industrial controllers.But there are many cases,OPCThe software does not meet the actual needs of use：
使用场景
1.OPCOnly works on the intranet,It is hoped that the data can be transmitted to the external network,随时随地查看
2.OPCData is difficult to store
3.Hope to show the data better,进行数据分析

整体交互图

1. dgiot_dtu从kepserver获取数据

在opc与kepserver完成连接之后,dgiot_dtu通过调用GetOpcDaService函数连接kepserverImplement data callback

 public OpcDaService GetOpcDaService(string host, string serviceProgId)
        {
           var service = hostCollection.Where(a => a.ServiceIds.Contains(serviceProgId) && a.Host == host)
                      .FirstOrDefault();

            if (service == null)
            {
                return null;
            }

            OpcDaService service1 = null;
            if (CheckServiceExisted(service, serviceProgId))
            {
                service1 = opcDaServices.Find(item => { return item.Host == service.Host && item.ServiceId == serviceProgId; });
            }
            else
            {
                OpcDaServer daService = new OpcDaServer(serviceProgId, service.Host);

                service1 = new OpcDaService()
                {
                    Host = service.Host,

                    ServiceId = serviceProgId,

                    Service = daService,

                    OpcDaGroupS = new Dictionary<string, OpcDaGroup>()
                };
                opcDaServices.Add(service1);
            }

            if (service1.Service.IsConnected == false)
            {
                try
                {
                    service1.Service.ConnectionStateChanged += new EventHandler<OpcDaServerConnectionStateChangedEventArgs>(ConnectionStateChanged);

                    service1.Service.Connect();
                }
                catch (Exception e)
                {
                    LogHelper.Log("Connect " + service1.Host + ", ServiceId " + service1.ServiceId + "error!!" + e.Message);
                }
            }

            return service1;
        }
COPY

2. dgiot_dtu数据发布

dgiot_dtuAfter data collection is complete,和dgiotPlatform connection is throughmqtt来进行连接,dgiot_dtuPublish as device side、dgiotThe platform acts as a server to subscribe

        public void ValueChangedCallBack(OpcDaGroup group, OpcDaItemValue[] values)
        {

            string groupKey = "";

            JsonObject properties = new JsonObject();
            values.ToList().ForEach(v =>
            {
                if (v.Item != null && v.Value != null)
                {
                    properties.Add(v.Item.ItemId, v.Value);
                    groupKey = v.Item.UserData as string;
                    OpcDa.setItems(groupKey, v.Item.ItemId, properties);
                }
            });
            string topic = "$dg/thing/" + productId + "/" + devAddr + "/properties/report";
            MqttClientHelper.Publish(topic, Encoding.UTF8.GetBytes(properties.ToString()));
            return;
            }
COPY

3.平台通过dlinkConvert data points

在dgiotWhen receiving subscription information,在dink中调用on_message_publish来匹配topictype for point-to-point conversion

on_message_publish(Message = #message{topic = <<"$dg/thing/", Topic/binary>>, payload = Payload, from = _ClientId, headers = _Headers}, _State) ->
    case re:split(Topic, <<"/">>) of
        [ProductId, DevAddr, <<"properties">>, <<"report">>] ->
            dgiot_dlink_proctol:properties_report(ProductId, DevAddr, get_payload(Payload));
        [ProductId, DevAddr, <<"firmware">>, <<"report">>] ->
            dgiot_dlink_proctol:firmware_report(ProductId, DevAddr, get_payload(Payload));
        _ ->
            pass
    end,
    {ok, Message};COPY

4. 平台通过task将数据存入TD,并使用mqttReport to the object model

After completing the point conversion,将数据存入TD数据库、At the same time, the data is also reported to the object model display

save_td(ProductId, DevAddr, Ack, AppData) ->
    case length(maps:to_list(Ack)) of
        0 ->
            #{};
        _ ->
            NewAck = dgiot_task:get_collection(ProductId, [], Ack, Ack),
            NewData = dgiot_task:get_calculated(ProductId, NewAck),
            Keys = dgiot_product:get_keys(ProductId),
            DeviceId = dgiot_parse_id:get_deviceid(ProductId, DevAddr),
            Interval = maps:get(<<"interval">>, AppData, 3),
            AllData = merge_cache_data(DeviceId, NewData, Interval),
            AllDataKey = maps:keys(AllData),
            case Keys -- AllDataKey of
                List when length(List) == 0 andalso length(AllDataKey) =/= 0 ->
                    ChannelId = dgiot_parse_id:get_channelid(dgiot_utils:to_binary(?BRIDGE_CHL), <<"DGIOTTOPO">>, <<"TOPO组态通道"/utf8>>),
                    dgiot_channelx:do_message(ChannelId, {topo_thing, ProductId, DeviceId, AllData}),
                    dgiot_tdengine_adapter:save(ProductId, DevAddr, AllData),
                    Channel = dgiot_product:get_taskchannel(ProductId),
                    dgiot_bridge:send_log(Channel, ProductId, DevAddr, "~s ~p save td => ProductId ~p DevAddr ~p ~ts ", [?FILE, ?LINE, ProductId, DevAddr, unicode:characters_to_list(jsx:encode(AllData))]),
                    dgiot_metrics:inc(dgiot_task, <<"task_save">>, 1),
                    NotificationTopic = <<"$dg/user/alarm/", ProductId/binary, "/", DeviceId/binary, "/properties/report">>,
                    dgiot_mqtt:publish(DeviceId, NotificationTopic, jsx:encode(AllData)),
                    AllData;
                _ ->
                    save_cache_data(DeviceId, AllData),
                    AllData
            end
    end.
COPY

5.Platform configuration object model and data display

[小 迪 点评]

• 鉴此,dgiotSpecifically provided based onOPC通讯的OPC接口,以实现OPCSimple transfer of data,解决行业痛点.

想了解更多 dgiot 的具体细节,欢迎大家在GitHub上查看相关源代码.