Data Consistency across Microservices with Outbox Pattern
Intent When moving to microservices architecture, one of the biggest challenges is dealing with data consistency among a swarm of microservices. Microservices are loosely coupled and separated by bounded contexts, such as a transaction through the trade lifecycle, which needs to be broken into local atomic transactions that can be executed by individual microservices within their own domain (not the other way around, i.e. a microservice knowing the internal constructs of other microservices’ databases). In order to achieve eventual consistency within a business transaction , the microservices need to be able to: persist data in relation to their own domain, and publish events to the event broker upon changes to asynchronously trigger the execution of other processing units. These are two distinct operations, often referred to as dual write . Because they are two separate operations of an atomic transaction, it became a source of consistency issues, performance dips and scal...