Read side external content

I am currently working on a design that uses Axon. One requirement is that some read-side data needs to be sourced from an external system that only has a query interface. The rest of the design relies on replicating data through events between services. I see the external data source as a compromise to the loosely coupled architecture and wondered if others have encountered this problem and if so how it was solved.

  • graham

Hi Graham,

if you’re sourcing read-side data from another system, that system is effectively the Q side of CQRS. The fact that that specific component isn’t sourced using events doesn’t sound too bad. Where do updates in that system come from?