WorkflowFM: A Logic-Based Framework for Formal Process Specification and Composition

Abstract

We present a logic-based system for process specification and composition named WorkflowFM. It relies on an embedding of Classical Linear Logic and the so-called proofsas-processes paradigm within the proof assistant HOL Light. This enables the specification of abstract processes as logical sequents and their composition via formal proof. The result is systematically translated to an executable workflow with formally verified consistency, rigorous resource accounting, and deadlock freedom. The 3-tiered server/client architecture of WorkflowFM allows multiple concurrent users to interact with the system through a purely diagrammatic interface, while the proof is performed automatically on the server.

A Pragmatic, Scalable Approach to Correct-by-Construction Process Composition Using Classical Linear Logic Inference

“…Our algorithms automate the appropriate deductions and alleviate this burden from the user. We have tied these with the diagrammatic interface of WorkflowFM [21], so that the user is not required to know or understand CLL or theorem proving, but merely sees inputs and outputs represented graphically. They can then obtain intuitive process compositions with the aforementioned correctness guarantees with a few simple clicks.…”

“…The systematic accounting of resources in our approach can be demonstrated through a hypothetical example from the healthcare domain [21]. Assume a process DeliverDrug that corresponds to the delivery of a drug to a patient by a nurse.…”

“…Using our CLL-based approach, the workflow output is either Reassessed which occurs if the drug failed, or T reated coupled with the unused ClinT ime, as shown at the bottom of Fig. 1 [21].…”

“…In general, this arXiv:1808.05490v2 [cs.PL] 3 Dec 2018 refers to the construction of systems in a way that guarantees correctness properties about them at design time. In this spirit, we have developed the WorkflowFM system for correct-by-construction process composition [21]. It relies on Classical Linear Logic (see Section 2.1) to rigorously compose abstract process specifications in a way that:…”

“…There are numerous aspects to and components in the WorkflowFM system, including, for instance, the diagrammatic interface (as shown in Fig. 1), the code translator, the execution engine, the process calculus correspondence, and the architecture that brings it all together [21]. In this particular paper we focus on the proof procedures that make such resource-based process compositions feasible and accessible.…”