This project shows an example of using Apache Seata for distributed transactions.

This project represents 4 services:

• apache-seata-shop-service
• apache-seata-inventory-service
• apache-seata-order-service
• apache-seata-billing-service

All of these work with a Postgres database, and additionally the Shop service makes API calls to the other three, such that all of this is considered to be a single distributed transaction.

We can start the project using Docker Compose.

$ docker compose up

This will start 6 containers:

• Apache Seata
• Postgres
• apache-seata-shop-service
• apache-seata-inventory-service
• apache-seata-order-service
• apache-seata-billing-service

Where apache-seaa-shop-service acts as the entrypoint into the application.

We can make HTTP calls into the application by making POST calls to the /shop/{mode} endpoint of the apache-seata-shop-service.

If the {mode} parameter is set to shop, inventory, order or billing then that service will fail during the transaction. Anything else and the call will be successful.

For example:

$ curl -X POST localhost:8080/shop/order

Will make a request that fails within the Order service.

We can access the database used by these services using Docker:

$ docker exec -it apache-seata-postgres-1 psql --user seata seata

This opens a psql prompt inside the database, allowing us to explore the state of all the tables.