Banking System Simulation

This project is a simulation of a banking system designed to demonstrate essential features like user authentication, account management, transaction processing, and report generation, with a focus on learning system design fundamentals.

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Features

Core Components:

• User Authentication: Supports secure internal and external user authentication with role-based access control.
• Account Management: Users can create, edit, and view accounts. Deletion of accounts is not supported to maintain integrity.
• Transaction Processing: Enables transactions between accounts owned by the same person, with validation to prevent unauthorized transfers.
• Report Generation: Provides reports on client transactions and registration history.

Technologies Used:

• MariaDB: Relational database for storing user and transaction data.
• Flask: Backend web framework.
• Redis: Cache for storing lists of user accounts for quick access.
• Docker Compose: For orchestrating application services.

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Project Structure

Key Directories & Files:

• compose.yml: Defines the Docker Compose configuration for the system.
• app/config/: Contains configuration files for the application.
  • cache.toml: Cache settings for Redis.
  • db.toml: Database connection settings for various modules.
  • permissions.toml: Role-based access permissions for endpoints.
  • reports.toml: Configuration for generating reports.
  • security.toml: Security settings, including the option to generate a random SECRET_KEY.
• app/src/: Contains the source code for various modules, including authentication, clients, external services, reports, and utilities.
• external-auth-service/: Mock external authentication service.

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Setup Instructions

Prerequisites:

• Docker installed.
• Docker Compose installed.

Steps to Run:

1. Clone this repository.
2. Navigate to the project directory.
3. Run the following command to start the application:

   docker-compose up --build

4. Access the application at http://127.0.0.1:5000.

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Configuration Details

Role-Based Permissions:

Permissions are defined in permissions.toml. For example:

• Admins have full access to manage clients, generate reports, and view statistics.
• Managers have limited access to transaction-related data.
• Regular users can perform account transfers and view their own account details.

Reports:

Reports are configured in reports.toml. Examples include:

• Client History Report: Monthly transaction details.
• Client Registered Report: Number of clients registered in a given month.

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Dependencies

The project requires the following Python packages:

• mariadb
• flask
• gunicorn
• redis
• simplejson
• requests

Install dependencies using:

pip install -r requirements.txt

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Security Notice

• The project allows the generation of a random SECRET_KEY during runtime to enhance security.
• External authentication is securely implemented through a dedicated service but communication between the monolith and the service is not encrypted.
• Database credentials in configuration files are not encrypted and are solely for demonstration purposes.

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License

This project is licensed under the MIT License. See the LICENSE file for details.