Using Microservices for Non-intrusive Customization of Multi-tenant SaaS

Enterprise software vendors often need to support their customer companies to customize the enterprise software products deployed on-premises of customers. But when software vendors are migrating their products to cloud-based Software-as-a-Service (SaaS), deep customization that used to be done on-premises is not applicable to the cloud-based multi-tenant context in which all tenants share the same SaaS. Enabling tenant-specific customization in cloud-based multi-tenant SaaS requires a novel approach. This paper proposes a Microservices-based non-intrusive Customization framework for multi-tenant Cloud-based SaaS, called MiSC-Cloud. Non-intrusive deep customization means that the microservices for customization of each tenant are isolated from the main software product and other microservices for customization of other tenants. MiSCCloud makes deep customization possible via authorized API calls through API gateways to the APIs of the customization microservices and the APIs of the main software product. We have implemented a proof-of-concept of our approach to enable non-intrusive deep customization of an open-source cloud native reference application of Microsoft called eShopOnContainers. Based on this work, we provide some lessons learned and directions for future work.