Tom De Wolf

Applying domain driven design in a modular fashion has implications on how your data is structured and retrieved. A modular domain consists out of multiple loosely coupled sub-domains, each having their own modular schema in the database. How can we migrate and evolve the database schema’s separately with each new sub-domain version? And how do we match this with reporting and cross-domain use cases, where aggregation of data from multiple sub-domains is essential?

A case study concerning an OSGi-based business platform for automotive services has driven us to solve these challenges without sacrificing the hard-worked-on modularity and loose coupling. In this presentation you will learn how we used Modular Domain Driven Design with OSGi. 'Liquibase' is elevated to become a first class citizen in OSGi by extending multiple sub-domains with automatic database migration capabilities. On the other hand, 'Elasticsearch' is integrated in OSGi to become a separate search module coordinating cross-domain use cases.

This unique combination enabled us to satisfy two important customer requirements. Functionally, the software should not be limited by module boundaries to answer business questions. Non-functionally, a future-proof platform is required in which the impact of change is contained and encapsulated in loosely coupled modules.