It's a simple java REST demo web app that implements wallet features.

• Java 11
• Spring Boot
• Spring Data JPA
• H2 (embedded, disk storage)
• Lombok
• Log4j2
• jUnit
• Mockito
• Jacoco
• Maven
• Travis CI
• Docker

The demo app implements wallet features.

Player can:

• Retrieve a current wallet's state
• Retrieve all wallet transactions
• Withdraw funds from a wallet
• Add funds to a wallet

All transactions have unique IDs.

The app automatically initializes H2 db with tables and data. There are 3 tables: players, wallets, transactions. data.sql and schema.sql are picked up automatically on start. Data is saved across app restarts. The persistence layer is done using Spring Data CrudRepository that provides a domain specific languages for making requests to the database.

The app writes logs via Log4j2 in stdout. Per each request the custom ThreadLogContextFilter filter adds automatically to each log record:

• RID (request ID based on UUID)
• IP (client's IP address)
• HOST (server name and port)

There is ExceptionHandlerControllerAdvice that handles exceptions. There are custom basic exceptions: BusinessLogicException and ServerException. ExceptionHandlerControllerAdvice responds with HTTP 450 to BusinessLogicException and to all inheritors by default. HTTP 500 is for Exception and ServerException.

The app's controller and the business logic class are tested. Jacoco plugin creates a report and shows code coverage.

Response: HTTP 200 OK

{
    "id": 1,
    "balance": 100.00
}

Response: HTTP 200 OK

[
    {
        "id": "2417a710-27b1-4cf0-9ecb-34c81c5df715",
        "amount": 50.00,
        "date": "2021-02-01T11:00:00.000+00:00"
    },
    {
        "id": "34df047f-0500-4933-9718-374f62dc32b8",
        "amount": 50.00,
        "date": "2021-02-01T10:00:00.000+00:00"
    }
]

Request body:

{
    "id": "1ef3c7e4-2d31-4198-b7dd-e72034cfa639",
    "walletId": 1,
    "amount": 150.52
}

Response: HTTP 204 No Content

Request body:

{
    "id": "87b8afe1-469d-42ed-a5ab-4a8494519dcb",
    "walletId": 1,
    "amount": 150.52
}

Response: HTTP 204 No Content

docker-compose -f docker-compose.yml up -d

After the app starts, it will take requests on the default 8585 port.