co⚡e: Sparkplug™ MQTT edge

// Components
_MQTT.IASyncPropertyProvider( IASyncPropertyProvider );
_MQTT.ITLSContextProvider( ITLSContextProvider );
_MQTT();
    _RecvSTATEMesg := _MQTT.GetSTATEMessage( MessageTopic => _RecvSTATETopic );
    onSTATEMessage( Topic := _RecvSTATETopic,
                    Message := _RecvSTATEMesg );
END_IF
IF _MQTT.NCMDMessageReceived() THEN
    Allows you to bidirectionally share sparkplug data from the edge of your network to a Primary Host Node
*)
{attribute 'reflection'}
FUNCTION_BLOCK PUBLIC FB_Edge IMPLEMENTS IEdge
VAR_INPUT
    KeepAlive     : UINT    := 60;   // eg: 60 (Value is in seconds)
    // Persistent Session (FALSE = DEFAULT)
    //  * You want the broker to queue the messages for the client and deliver them as soon as the client is back online.
    //  * The client has limited resources. 
    //  * The client needs to reNumberOfMetricse all QoS 1 and 2 publish messages after a reconnect.
    //  
    //  Clean session (TRUE)
    //  * You don
t want the broker to store session information or retry transmission of QoS 1 and 2 messages.
    Username     : WSTRING := ""; // specify a username if any (optional)
    UseTLS       : BOOL; // Enables usage of the TLS encryption (optional)
    publishPeriod       : UINT; // eg: 5000 (Value is in milliseconds)
    //Static initialization, as shown in the following code snippet;
    //VAR
    //    commonName : STRING := 'MyRasPi';
    IASyncPropertyProvider : MQTT.NBS.IAsyncProperty; // Runs the connect process in a own background task. Use this property if the connection setup takes longer than one task cycle (e.g. TLS connections) 
END_VAR
VAR_OUTPUT
    Connected       : BOOL;
    SessionState    : SparkplugSessionStateType;
	{attribute 'no_copy'}
    itfEdge         : IEdge := THIS^;
    NumberOfDevices : UDINT;
VAR
    _LockTimesArray   : ARRAY[1..8] OF TIME := [4(TIME#30S0MS), 2(TIME#1M0S0MS), TIME#2M0S0MS, TIME#4M0S0MS]; // could be made accessible public  
    _LockTimeRemaining    : TIME; // Duration of Out Time Period = FALSE remaining
    _cPrimaryHostID       : WSTRING; // Corrected PrimaryHostID, contains no illegal chars
    _cNodeName            : WSTRING; // Corrected NodeName, contains no illegal chars
    _MQTT                 : FB_EdgeMQTT;
    _MQTT_eError          : MQTT.MQTT_ERROR;
    _Devices              : List; // Handles all connected Devices
    _prevNumberOfDevices  : UDINT;
    _ItfCurElement        : IElement;
    _ItfCurDevice         : ISparkplugDevice;
    _Initialise           : BOOL;
    _Initialised          : BOOL;
    _SubscribeNCMD        : BOOL;
    _NodeBirthPublished   : BOOL;
    _DisablePublisher     : BOOL;
    _LastWillTopic        : WSTRING(GC_Sparkplug.supported_string_lengths);
    _NDEATH               : FB_RemoteMetric;    // contains the current NDEATH BDSeq
    _NDEATHPayload        : ARRAY[0..255] OF BYTE; // what is the maximum size of this payload?
    _LastWillRetain       : BOOL := FALSE;
    _NBIRTH               : FB_RemoteMetric := (_dataType := MetricDataType.UInt64);      // contains the current raw NBIRTH seq
    _Blob                 : ARRAY[0..65535] OF BYTE; // buffer for encoded messages
    _BlobSize             : UDINT;                   // current encoded message size
    _PublishNDATA         : BOOL;
    _ChangeError          : ERROR;
    _ChangeDetected       : BOOL;  // At least 1 Signal change has been detected; RBE needed next PublishInterval 
    _CurrentChanges       : UDINT; // Number of detected changes, each changes reflects 1 Signal     
    _RecvSTATEMesg        : STRING;
    _RecvSTATETopic       : WSTRING(GC_Sparkplug.supported_string_lengths);
    _RecvNCMDMesg         : REFERENCE TO FB_PayloadSimpleDecoder;
    _RecvNCMDTopic        : WSTRING(GC_Sparkplug.supported_string_lengths);
    {attribute 'instance-path'}
    _POU : STRING;
15662
{8e575c5b-1d37-49c6-941b-5c0ec7874787}
ChildObjectGuids
AddAttributeSubsequent