This is a simple banking service implemented in Go that simulates basic banking operations, including:
- Account creation with support for multiple currencies.
- Deposits, withdrawals, and fund transfers.
- Role-based user permissions (Customer, Banker, Teller, Exchange Manager).
- Currency exchange with configurable exchange rates.
- Backup funds feature, allowing withdrawals from multiple accounts if one has insufficient balance.
- Thread-safe operations using
MutexandRWMutexto ensure concurrency safety.
-
Users and Roles:
- Customer: Manages their accounts.
- Banker: Creates users and accounts.
- Teller: Performs deposits and withdrawals for customers.
- Exchange Manager: Manages currency exchange and sets exchange rates.
-
Account Operations:
- Create multiple accounts per user with different currencies.
- Deposit and withdraw funds.
- Transfer funds between accounts with the same currency.
-
Currency Exchange:
- Exchange between different currencies using stored exchange rates.
-
Backup Funds:
- If enabled, withdrawals can use multiple accounts to cover the required amount.
-
Concurrency Safety:
- Thread-safe operations using
sync.Mutexandsync.RWMutexto prevent race conditions.
- Thread-safe operations using
-
Prerequisites:
- Go (version 1.20+)
-
Clone repo:
git clone git@github.com:archix/simple-bank-service.git
-
Run the Tests:
go test -v
bank := NewBankService()
bank.CreateUser(1, Customer, true) // Create a Customer with backup fund usage enabledaccID, err := bank.CreateAccount(1, 1000, USD) // Create a USD account with an initial deposit of 1000
if err != nil {
fmt.Println("Error:", err)
}bank.Deposit(1, accID, 500) // Deposit 500 USD into the accounterr := bank.Withdraw(1, accID, 200) // Withdraw 200 USD from the account
if err != nil {
fmt.Println("Error:", err)
}bank.Transfer(acc1ID, acc2ID, 100) // Transfer 100 USD from one account to anotherbank.SetExchangeRate(USD, EUR, 0.85) // Set exchange rate from USD to EURerr := bank.ExchangeCurrency(1, acc1ID, acc2ID, 100) // Exchange 100 USD to EUR
if err != nil {
fmt.Println("Error:", err)
}var wg sync.WaitGroup
numDeposits := 10
for i := 0; i < numDeposits; i++ {
wg.Add(1)
go func() {
defer wg.Done()
bank.Deposit(1, accID, 100)
}()
}
wg.Wait()Run the following command to execute all tests, including concurrency tests:
go test -vSample Output:
=== RUN TestConcurrentDeposits
--- PASS: TestConcurrentDeposits (0.01s)
=== RUN TestConcurrentWithdrawals
--- PASS: TestConcurrentWithdrawals (0.01s)
=== RUN TestConcurrentTransfers
--- PASS: TestConcurrentTransfers (0.01s)
PASS
ok bankservice 0.03s
bankservice/
│
├── service.go # Core banking service logic
├── service_test.go # Tests for the banking service
├── go.mod # Go module file
├── LICENSE # License details
└── README.md # Project documentation
- API Layer: Expose the service via REST or gRPC endpoints.
- Database Integration: Store users and accounts in a persistent database (e.g., PostgreSQL).
- Authentication: Add user authentication and authorization.
- Improved Currency Exchange: Integrate real-time exchange rates using an external API.
Feel free to open issues or submit pull requests if you'd like to contribute!
- Igor Dakic – Developer of the Go Banking Service