Group colloquium: Distributed programming using role-parametric session types in Go
When: April 18, 2019, 15:45-16:30
Where: Ravelijn 2503
Who: Sung-Shik Jongmans
In this talk, I'll presents a framework for the static specification and safe programming of message passing protocols where the number and kinds of participants are dynamically instantiated.
More precisely, we developed the first theory of distributed multiparty session types (MPST) to support parameterised protocols with indexed roles; our framework statically infers the different kinds of participants induced by a protocol definition as role variants, and produces decoupled endpoint projections of the protocol onto each variant. This enables safe MPST-based programming of the parameterised endpoints in distributed settings: each endpoint can be implemented separately by different programmers, using different techniques (or languages). We proved the decidability of role variant inference and well-formedness checking, and the correctness of projection.
We implemented our theory as a toolchain for programming such role-parametric MPST protocols in Go. Our approach is to generate API families of lightweight, protocol- and variant-specific type wrappers for I/O. The APIs ensure a well-typed Go endpoint program (by native Go type checking) will perform only compliant I/O actions w.r.t. the source protocol. We leveraged the abstractions of MPST to support the specification and implementation of Go applications involving multiple channels, possibly over mixed transports (e.g., Go channels, TCP), and channel passing via a unified programming interface. We evaluated the applicability and run-time performance of our generated APIs using microbenchmarks and real-world applications.