Data Handling

This page gives a more detailed description of initialisation and doStep of RMQFMU. The description is mainly carried out via diagrams, where some functions are referred to by name. Such functions are described in the section Functions.

Initialization

The initialization process of RabbitMQ FMU is peculiar in the sense that it needs to have an output for all messages. For this reason, the initialization has to occur when fmi2EnterInitializationMode is invoked on RabbitMQ FMU.

Functions

Some functions are described in this section that are used in the diagram in the subsequent section.

RabbitMQFMU.configure()
  • Configure the RMQFMU based on the configuration within the model description file.
RabbitMQFMUCore.ProcessIncoming
  • Move lookahead amount of messages per message type from IncomingUnprocessed to IncomingLookahead
  • Sort lookahead according to time
RabbitMQFMUCore.ProcessLookahead
  • Move message from incomingLookahead to currentData if newer.
RabbitMQFMUCore.check

Returns false if any of the following cases occur for a message: msg in currentData:

  • Missing in currentData
  • CurrentData holds a future value: msg.time > simulationTime
  • CurrentData holds an expired value: (msg.time + maxAge) < simulationTime

Flow of EnterInitializationMode

title EnterInitializationMode hide footbox boundary "Co-simulation Master" as Master participant RabbitMQFMUInterface as FMUI participant RabbitMQFMUCore as FMUC database "RabbitMQ Server" as server Master -> FMUI: EnterInitializationMode FMUI -> FMUI: configure() connection for content data (CCD) FMUI -> server: Publish Ready message on CCD FMUI -> FMUI: configure() connection for system health data (CSHD) FMUI -> FMUI: initializeCoreState() FMUI -> FMUI: set StartTime = Time Now loop TimeNow - StartTime < communicationTimeOut alt There is a message FMUI -> FMUC: initializeResult = Initialize() group initialize function FMUC -> FMUC: startOffsetTime = calculateStartTime() FMUC -> FMUC: initializeResult = check(0) FMUC --> FMUI: initializeResult end alt initializeResult is True FMUI --> Master: True end else There are no messages server --> FMUI: False end end

Flow of thread consuming from the RabbitMQ server

title EnterInitializationMode hide footbox participant RabbitMQFMUInterface as FMUI participant RabbitMQFMUCore as FMUC database "RabbitMQ Server" as server loop Until Consumer Thread is Stopped FMUI -> server: ConsumeSingleMessage(&msg) | (CCD) alt There is a message server --> FMUI: msg = parse(message) alt Parse success FMUI -> FMUC: AddToIncomingUnprocessed(msg) end else There are no messages server --> FMUI: False end end

Flow of the DoStep

This section describes the doStep operation of RabbitMQ FMU.

Functions

Some functions are described in this section that are used in the diagram in the subsequent section.

RabbitMQFMUCore.check
Described in functions section of the initialization section.
RabbitMQFMUCore.ProcessIncoming
  • Move lookahead amount of messages per message type from IncomingUnprocessed to IncomingLookahead
  • Sort lookahead according to time
RabbitMQFMUCore.ProcessLookahead
  • Move value from incomingLookahead to currentData if <= simulationTime and newer than the value in currentData. Otherwise keep in IncomingLookahead

Flow of DoStep Operation

title DoStep operation hide footbox boundary "Co-simulation Master" as Master participant RabbitMQFMUInterface as FMUI participant RabbitMQFMUCore as FMUC database "RabbitMQ Server" as server Master -> FMUI: doStep(currentCommunicationTime, communicationStepSize) FMUI -> FMUI: simulationTime = applyPrecision(\ncurrentCommunicationTime+communicationStepSize) alt There is change of inputs FMUI -> FMUC: Package json message FMUI -> server: Send message with changed inputs end FMUI -> FMUC: Publish system health data | (CSHD) FMUI -> FMUC: process(simulationTime) FMUI -> FMUI: StartTime = Time Now loop TimeNow - StartTime < communicationTimeOut alt There is a message alt There is system health data FMUI -> FMUI: Calculate time discrepancy end FMUI -> FMUC: processResult = process() group process function FMUC -> FMUC: processIncoming() FMUC -> FMUC: processLookahead() FMUC -> FMUC: check() FMUC -> FMUI: processResult end alt processResult == True FMUI -> Master: True else processResult != True FMUI -> Master: False end else No message FMUI -> Master: False end end