Banking Service

This application is a banking service that depends on Temporal, Redis, and PostgreSQL. The required resources are orchestrated using Docker Compose, and the database is automatically migrated once all services are healthy.

Prerequisites

Ensure that Docker and Docker Compose are installed on your machine

Running the Application

• Clone the repository and change into the project directory:

git clone https://github.com/ulascansenturk/service.git && cd service

• docker-compose up

This command will:

• Launch the required services (Temporal, Redis, PostgreSQL, API, Temporal-Transfers-Workfer).
• Wait for all services to become healthy.
• Automatically run the database migrations.

Access the Temporal UI once all services are running at: http://localhost:8233/

The Temporal UI can be used to monitor transfer workflows.

Making a Money Transfer

To make a money transfer, you first need to create a user. The application will automatically create a bank account for the user in the background.

Reliability of Transfers

The reliability of money transfers is ensured through the use of a Redis lock before the actual transfer process begins. This locking mechanism prevents race conditions and ensures that only one transfer can occur for a specific source account at a time.

Example Request:

To create a user and their associated bank account, use the following curl command:

curl --location 'localhost:3000/v1/users' \
--header 'Content-Type: application/json' \
--data-raw '{
    "data":{
        "email":"[email protected]",
        "password": "random-password",
        "firstName":"Ulascan",
        "lastName":"Senturk",
        "currencyCode":"USD",
        "balance":10000
    }
}'

Example Response:

{
    "bankAccount": {
        "balance": 10000,
        "currency": "USD",
        "id": "fa8ede6f-8f36-4e71-93ec-4df28af5d0c5",
        "status": "ACTIVE",
        "user_id": "a0e42ad6-474b-4f99-bbe8-4da7ec75ab65"
    },
    "user": {
        "email": "[email protected]",
        "first_name": "Ulascan",
        "id": "a0e42ad6-474b-4f99-bbe8-4da7ec75ab65",
        "last_name": "Senturk"
    }
}

To trigger a money transfer between two accounts, use the following curl command:

curl --location 'localhost:3000/v1/transfers' \
--header 'Content-Type: application/json' \
--data '{
    "data":{
        "reference_id": "7ad62627-2a80-4e62-819e-477802449da4", // Random generated uuid, also workflow id
        "amount":100,
        "fee_amount":230, // Optional
        "sourceAccountID":"068d81de-be46-4d59-a20a-8d3c168504ff",
        "destinationAccountID": "60f4c37f-3509-41a8-b3c1-836c0bb70d39"
    }
}'

Example Response:

{
    "SourceTransactionReferenceID": "0d305986-3fde-5792-a867-a625d898e9fb",
    "DestinationTransactionReferenceID": "beecbcc3-bd14-5b6a-93f3-b320694527c4",
    "FeeTransactionReferenceID": "a0f60930-b58d-57b7-bb90-463c9f42e2f2",
    "FeeTransaction": {
        "id": "b11cf134-f3b0-400e-88c6-4902230a24fb",
        "user_id": "3f1060e4-18f2-4b23-bc93-bd04ae29f9e7",
        "amount": 230,
        "account_id": "068d81de-be46-4d59-a20a-8d3c168504ff",
        "currency_code": "USD",
        "reference_id": "a0f60930-b58d-57b7-bb90-463c9f42e2f2",
        "metadata": {
            "LinkedAccountID": "068d81de-be46-4d59-a20a-8d3c168504ff",
            "LinkedTransactionID": "a0f60930-b58d-57b7-bb90-463c9f42e2f2",
            "OperationType": "Fee Transfer",
            "timestamp": "2024-08-16 17:08:28.431509 +0300 +03 m=+28.017843918"
        },
        "status": "SUCCESS",
        "transaction_type": "OUTGOING_FEE",
        "created_at": "2024-08-16T17:08:28.433178+03:00",
        "updated_at": "2024-08-16T17:08:28.445264+03:00"
    },
    "SourceTransaction": {
        "id": "24dabadb-c354-40d6-b16d-8eb2f9b0054f",
        "user_id": "3f1060e4-18f2-4b23-bc93-bd04ae29f9e7",
        "amount": 100,
        "account_id": "068d81de-be46-4d59-a20a-8d3c168504ff",
        "currency_code": "USD",
        "reference_id": "0d305986-3fde-5792-a867-a625d898e9fb",
        "metadata": {
            "DestinationAccountID": "60f4c37f-3509-41a8-b3c1-836c0bb70d39",
            "LinkedAccountID": "068d81de-be46-4d59-a20a-8d3c168504ff",
            "LinkedTransactionID": "0d305986-3fde-5792-a867-a625d898e9fb",
            "OperationType": "Transfer",
            "timestamp": "2024-08-16 17:08:28.404834 +0300 +03 m=+27.991168376"
        },
        "status": "SUCCESS",
        "transaction_type": "OUTBOUND",
        "created_at": "2024-08-16T17:08:28.413771+03:00",
        "updated_at": "2024-08-16T17:08:28.439805+03:00"
    },
    "DestinationTransaction": {
        "id": "a9bc31dd-e12c-4d28-b4c1-730ba9e1eae2",
        "user_id": "32f40751-b202-4598-bbd2-86d9fda9136a",
        "amount": 100,
        "account_id": "60f4c37f-3509-41a8-b3c1-836c0bb70d39",
        "currency_code": "USD",
        "reference_id": "beecbcc3-bd14-5b6a-93f3-b320694527c4",
        "metadata": {
            "DestinationAccountID": "60f4c37f-3509-41a8-b3c1-836c0bb70d39",
            "LinkedAccountID": "60f4c37f-3509-41a8-b3c1-836c0bb70d39",
            "LinkedTransactionID": "beecbcc3-bd14-5b6a-93f3-b320694527c4",
            "OperationType": "Transfer",
            "SourceAccountID": "068d81de-be46-4d59-a20a-8d3c168504ff",
            "timestamp": "2024-08-16 17:08:28.433887 +0300 +03 m=+28.020221084"
        },
        "status": "SUCCESS",
        "transaction_type": "INBOUND",
        "created_at": "2024-08-16T17:08:28.434807+03:00",
        "updated_at": "2024-08-16T17:08:28.443416+03:00"
    }
}

Screenshot from Temporal UI Transfer workflow:

Detailed view