concept Accounting Service in category microservice

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Accounting Service— Handles billing and payments

ACID (Atomicity, Consistency, Isolation, Durability) transactions greatly simplify the job of the developer by providing the illusion that each transaction has exclusive access to the data. In a microservice architecture, transactions that are within a single service can still use ACID transactions. The challenge, however, lies in implementing transactions for operations that update data owned by multiple services. For example, as described in chapter 2, the createOrder() operation spans numerous services, including Order Service, Kitchen Service, and Accounting Service. Operations such as these need a transaction management mechanism that works across services.

Accounting Service consumes the OrderCreated event and creates a CreditCardAuthorization in a PENDING state.

Accounting Service consumes the TicketCreated and ConsumerVerified events, charges the consumer’s credit card, and publishes the CreditCardAuthorized event.

Figure 4.5. The sequence of events in the Create Order Saga when the authorization of the consumer’s credit card fails. Accounting Service publishes the Credit Card Authorization Failed event, which causes Kitchen Service to reject the Ticket, and Order Service to reject the Order.