Addressing Serverless Computing Vendor Lock-In through Cloud Service Abstraction

Serverless Function-as-a-Service (FaaS) platforms enable easy deployment and hosting of microservices and have gained great traction among software developers. FaaS platforms, however, only host compute-based functionality of applications resulting in vendor lock-in as applications rely on supporting services known as Backend-as-a-Service (BaaS) offered by the cloud provider for key features such as data persistence. Migrating FaaS code to different cloud providers is made more challenging as a result of these dependencies on vendor-specific services. Cloud service abstraction libraries have been developed to alleviate vendor lock-in, but these libraries were largely developed prior to the advent of serverless computing and have not been evaluated in this context. This paper investigates the use of cloud service abstraction libraries to interface with object storage, a key BaaS used in FaaS code. We investigate the utility of these libraries to improve the portability of code to enable easier migration between cloud providers. We investigate performance of seven FaaS functions on AWS and Google Cloud that use object storage using the Apache jclouds abstraction library vs. platform-specific APIs and assess code quality metrics. We then conduct an empirical study leveraging computer science students enrolled in cloud computing courses to assess the impact of cloud abstraction libraries on FaaS function code portability.