A demand leads to a bill which then leads to payment by a citizen. Once payment is done, the application status has to be updated. Since we have a microservices architecture, the two services can communicate with each other either through API calls or using events.
The collection service publishes an event on a Kafka topic when payment is collected for an application. Any microservice that wants to get notified when payments are done can subscribe to this topic. Once the service consumes the payment message, it will check if the payment is done for its service by checking the businessService code. The application status changes to PAID or triggers a workflow transition.
Steps
For our guide, follow the steps below to create payment back update consumer -
Create a consumer class by the name of PaymentBackUpdateConsumer. Annotate it with @Component annotation and add the following content to it -