CoreBank

A C++23 banking backend simulation with an HTTP REST API. Manages the hierarchical relationship between a Bank, its Clients, their Bank Accounts, Transactions, Loans, and Bonds.

Features

• 4 account types: Personal, Savings, Retirement, Investment
• Currencies: USD, EUR, GBP, JPY, CHF with automatic conversion
• Monthly fees per account type, interest accrual on savings/retirement
• Investment bonds with annual coupons and maturity payouts
• Loan system with credit-score-based approval and monthly payments
• JSON persistence — data loaded from and saved to JSON files
• Scheduler for automated monthly fee/interest/bond/loan processing
• REST API via cpp-httplib

Project Structure

CoreBank/
├── main.cpp                  # Entry point
├── CMakeLists.txt            # Build configuration
├── data/                     # JSON seed data
│   ├── bank.json
│   ├── clients.json
│   ├── accounts.json
│   ├── bonds.json
│   └── loans.json
├── models/                   # Domain model
│   ├── cbaccount/            # BankAccount & derivatives
│   ├── cbbank/               # Bank singleton
│   ├── cbclient/             # Client
│   ├── cbinstrument/         # Bond
│   ├── cbloan/               # Loan
│   └── cbtransaction/        # Transaction
├── server/                   # HTTP server & service layer
│   ├── HttpServer.h/cpp      # Route handlers
│   ├── BankService.h/cpp     # Business logic facade
│   ├── Scheduler.h/cpp       # Periodic jobs
│   └── ApiTypes.h            # AccountKind enum
├── utils/                    # Utilities
│   ├── cbbanking/            # InterestAccrual, ReportGenerator
│   ├── cbcurrency/           # CurrencyConverter
│   ├── cbdate/               # Date parsing & arithmetic
│   ├── cbexception/          # Custom exceptions
│   ├── cbjson/               # JsonLoader, JsonStore, JsonHelpers
│   ├── cblogger/             # Logger
│   └── cbvalidation/         # IBAN, date, amount validation
├── ext/                      # External headers (nlohmann/json, httplib)
└── postman/                  # Postman collection

Build & Run

Prerequisites

• CMake >= 3.26
• C++23 compiler (GCC, Clang, MSVC)

Build

cmake -B build
cmake --build build

Run

The executable expects the data/ directory as a relative path. Run from the project root:

cd CoreBank/
./build/oop                    # Linux/macOS
.\build\Release\oop.exe        # Windows (MSVC)
.\cmake-build-debug\oop.exe    # Windows (CLion / MinGW)

Important: The server reads/writes JSON files using relative paths like data/accounts.json. The working directory must be the project root for this to work. If you run from a different directory (e.g. cmake-build-debug/), the files will be read/written there instead.

Defaults

• Port: 8080
• Log file: ./logs/log-<timestamp>.txt

Seed Data

The server loads initial data from data/*.json at startup. Modify these files to change starting state:

File	Contains
bank.json	Bank name & SWIFT code
clients.json	Client list (CNP, name, address, income)
accounts.json	Accounts with type, IBAN, balance, currency, owner
bonds.json	Investment bonds per account
loans.json	Client loans (not yet loaded)

REST API

Import the Postman collection at postman/CoreBank.postman_collection.json for a complete list of all endpoints with example bodies.

All requests and responses use Content-Type: application/json.