July 26, 2017 conference call

[colancto]

The Methods & Tools Special Interest Group held a conference call on July 26, 2017. Bill BARRETT (U.S. Environmental Protection Agency), Jasper van BATEN (AmsterCHEM), Michael HLAVINKA (Bryan Research & Engineering) and myself attended the call.

The call was dedicated to the review of the proposal of a Common interface specification for reporting. While not specific to COBIA, the proposal is taking advantage of COBIA to be shaped, defined, prototyped and tested.

Currently the only Process Modelling Component on which a reporting interface is defined is the Unit Operation (ICapeUnitReport). Indeed Unit Operations may need to provide information to the end-user that cannot be just made available through parameters, or even if this can be made available through output parameters, the meaning of these parameters being limited to the PMC, there is a need to report on these in a more elaborate way, which leads to a report. The "may need" is important here and the specific reporting interface for Unit Operation is non mandatory since a number of Unit Operations may not need to provide any report.

It may be noted that nothing prevents another type of Process Modelling Component to implement the ICapeUnitReport interface which is part of the Unit Operation interface specification. But its name seems to make it specific to Unit Operations and Process Modelling Environments have not been developed to look at such an interface on other types of PMCs that Unit Operations.

Within the development of the Flowsheet Monitoring interface specification, it appeared necessary to provide for reporting by such a PMC. Rather than defining such a reporting interface as specific to Flowsheet Monitoring, it seemed more reasonable to look for a common interface specification providing reporting capabilities.

It could be envisioned that such a reporting capability is of use also to PMCs like numerical solvers in order to report on their convergence path for instance.

Another issue seemed necessary to address. With the ICapeUnitReport interface, only plain text reports were considered at first. Looking back to when this interface was designed, it is not surprising. Other formats of reports could come handy. The Errata and Clarifications document issued on the Unit Operation interface specification proposed a work-around to let HTML-based reports be handled. Using NamedValues within SimulationContext, a PME may advertise that it supports HTML-type reports and the Unit Operation may catch this information and accordingly issue its reports in such a format. Having a generic reporting common interface enables us to modify the workflow, letting the PMC advertise to the PME in which formats reports may be issued and then the PME may request this report in this format. Apart from plain text and HTML, it is envisioned that additional formats supporting images could be considered.

So far reports are provided as a whole by a PMC and embedded by the PME in their entirety within the PME report. Another enhancement could be to define a report using XML and a common document object model between PMCs and PME. That way, the PME could choose to extract parts of a PMC report for inclusion in its own report. Not sure that will be easy to achieve since it relies on a common understanding of what a PMC issues within a report. Still could be worth the try.

Note that at this stage, such an interface is a proposal and there is no rush to adopt it. Especially COM-based PMCs and PMEs will still be able to use the ICapeUnitReport interface since COBIA and COMBIA will tackled the interpretation of calls to ICapeUnitReport or its implementation as the new reporting interface.

Your feedback on this proposal is welcome.