Table of contents

1. Introduction
2. Installation
   1. Truffle
   2. Ganache
   3. Flask
   4. Web3
3. Instruction

1. Introduction

This repository demonstrates an MVP (Minimum Viable Product) of a P2P Lending Platform based on blockchain technology. It is developed as a part of the FinTech courses in Erasmus University Rotterdam - School of Management. The course highlights the importance of applying modern techniques to improve challenges in the finance sectors. Overall, this MVP uses the following tools:

Key Tools Utilized:

Truffle and Ganache: These are Node.js-based tools used for simulating the Ethereum blockchain environment. They facilitate smart contract development, testing, and deployment without incurring actual blockchain costs.

Flask: A lightweight Python web framework utilized to render a local HTML user interface. Flask handles backend operations and serves as the intermediary between the frontend UI and blockchain interactions.

Web3: Used in the backend to establish interactions between the Flask-powered backend and the Ethereum blockchain. Web3 enables transaction execution, smart contract interactions, and data retrieval.

The project aims to showcase the feasibility and functionality of a blockchain-powered P2P lending platform. It emphasizes practical implementation and demonstration of blockchain technology's potential in financial applications, focusing on security, transparency, and efficiency enhancements.

2. Installation

The installation instruction is based on the author's operating system Windows 11 Home Version 21H2. Here the term terminal refers to the built-in Command Prompt or equivalently, the terminal of any compilers (Spyder, VSCode, PyCharm, etc.).

In most cases, commands have to be executed in the same directory as the file. For example, to move from the root directory with the form of C:\Users to the Desktop directory C:\Users\Desktop, type the following:

cd Desktop

To return to the parent directory, use:

cd ..

2.1 Truffle

Truffle is a development framework for Ethereum. It requires Node.js and npm (Node Package Manager) to be installed. Download and install Node.js from nodejs.org.

Then Truffle can be installed globally by typing the following into the terminal:

npm install -g truffle

The installation can be verified by checking the version through the terminal:

truffle version

2.2 Ganache

Ganache is a personal blockchain for Ethereum development that runs locally on your PC. It simulates an Ethereum network environment without the need for real Ether, making it ideal for development and testing purposes. Follow the official instruction to download and install Ganache from Ganache.

2.3 Flask

Flask is a lightweight web framework for Python, ideal for building web applications. Open your terminal and install Flask using pip.

pip install flask

If wanted, Flask installation can be verified by creating a simple Flask app and running it. Create a Python script app.py with the following structure:

from flask import Flask
app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

if __name__ == '__main__':
    app.run(debug=True)

Run the above script. Then type in the terminal (at same directory as app.py):

python app.py

Then open your browser and go to http://127.0.0.1:5000. You should see a page with "Hello, World!".

2.4 Web3

Web3.py is a Python library for interacting with Ethereum. Use pip to install web3 as follows:

pip install web3

If wanted, the installation can be verified by checking the version in a Python terminal or script

import web3
print(web3.__version__)

3. Instruction

If you want to run my outcome, please first clone the repository. Change the current working directory to the location where you want the cloned directory and type:

git clone https://github.com/dolienky/fintech_ezmoney.git

• Now you have to connect Ganache to the backend. Open Ganache and click "New Workspace" to create a new workspace. Name your workspace and click "Add project". Here you should open the truffle-config.js file in the backend folder. Then, click Start to initiate a Ganache workspace.
• After a few seconds, your local Ethereum blockchain is ready. By default, you have access to 10 accounts with 100 ETH each. Note that this does not mean the blockchain only has 10 nodes. In the top section, you can manage the Accounts, Blocks, Transaction, Contracts, Events, and Logs. Click on Contracts and verify that there is a contracted called P2PLending with address Not Deployed.
• P2PLending is a Solidity (.sol) file that acts as the Smart Contract. It is integrated into the blockchain and will automatically be executed as long as the conditions are met. The uploaded P2PLending.sol contains the following function: Create Loan Request, Fund Loan Request, Repay Loan, Get Loan Request, and Get Num Loan Requests.
• To deploy the contract, open the terminal and MAKE SURE that your directory is at the backend folder. Then type the following to first compile the contract (this will create a P2PLending.json file in build/contracts to store data in the future):

truffle compile

• When finished, you can continue with the deployment by typing the following:

truffle migrate --reset

• Once finished, you should see a successful message. Now in the Transaction tab in Ganache UI, you should see 1 Contract Creation and in the Contract tab, you can see the address of the contract. It is now part of the blockchain with a unique address and no one can change it, if anyone makes any changes to the contract, the address will be different since re-deployment is required to update the changes. This highlights the transparency and high security of P2P Lending Platform that uses blockchain technology.
• Click on Contracts tab in Ganache UI and copy the contract address. Now open app.py file and paste this to the variable contract_address (should be at line 28). Save app.py to apply the changes. Then in the terminal, type the following to initiate the Flask session and you are ready to use my MVP by opening http://127.0.0.1:5000:

python app.py

• If you want to test the repayLoan function (in which borrower pays one of the installments), please use the private key of one of the accounts created in the beginning by Ganache. One of the limitations of Ganache is that, you can make transaction from existing account to new account, but not vice versa. The smart contract itself works well.