Supply is about Making a Crowdfunding Decentralized App using Blockchain Technology on top of Ethereum Network.

The project involves creating a Blockchain-powered App designed for Decentralized Crowdfunding, emphasizing transparency, security, and decentralization. It utilizes Smart Contracts, which are immutable artificial contacts responsible for enforcing agreements without the possibility of alteration after deployment....

We have two primary actors:

• Investor/ Donator/ Fundraiser.
• Campaign launcher.

Investors can:

• Login with Meta Mask Wallet
• Donate to campaigns
• Refund Money
• View Campaigns

Campaign launchers can:

• Launch Campaign
• Close Campaign
• Edit Campaign
• View Campaign
• Login with MetaMask
• Withdraw Funds

The Frontend was made by ReactJS, the Backend by NodeJS, the Blockchain by Solidity, testing was by Mocha, Chai and Jest.

It has A frontend connected to both Blockchain and Backend, Blockchain is for verifying transactions and backend to serve and store information to the backend database (MongoDB). It also uses decentralized file storage called IPFS for image storage.

• Test Driven Development: Since once Smart contracts are deployed to the Blockchain Network, it can not be changed. A Test Driven Development approach was made to write tests and mocks as scenarios and then write the required code to pass these tests.

• JWT authentication.
• Define CORS policy to allow only specific domains.
• Implemented Header security using the Helmet package.
• Passwords are hashed using an irreversible algorithm bcrypt.
• Implemented a strict endpoint validation system using Joi.

All routes are versioned by default GET - api/v1.

• CRUD (Create, Read, Update, Delete) for all resources using RESTful API design.
• Index Pagination - Search - Sort - Select - Filter.
• API Versioning (v1).
• Best Practices & Clean Code (MVC, SOLID, DRY, KISS).
• Error Handling System (Generic error handler middleware with Correct HTTP Status Code & Error message).

• GET - api/v1/ - get campaigns.
• POST - api/v1/ - add campaigns.
• GET - api/v1/donations/:campaignId/:address - get user donations.
• GET - api/v1/:campaignId - get campaign by ID.
• GET - api/v1/profiles/:address - get campaign User.
• PATCH - api/v1/:id - get campaigns.
• DELETE - api/v1/:id - Delete campaign.
• GET - api/v1/uploadImage - Upload image for the campaign.

• GET - api/v1/ - get rewards.
• GET - api/v1/profiles/:address - get user rewards.

1. First of all, you have to configure the .env file using your credentials like MongoDB URL, Password, etc.
2. Second, install dependencies from the frontend, backend, and blockchain folders by navigating into the folder using cd <folder-name> and

npm install
npm run dev

It will run the project's frontend and backend on ports configured in the .env file. You should deploy the blockchain part using either a fake mainnet by using Alchemy's API key or deploy it on the Sapoli testnet.

 npm run test

Navigate to the blockchain folder and

 npm run deploy

and chooose one account from multiple ones to be your private and public key addresses and configure them and add them to the wallet (MetaMask)

We faced price fluctuations in cryptocurrencies in general, so we decided to use stable coins that are backed by the US dollar. We used DAI and converted currencies, whether it is ETH or any other tokenized currency.

• Node.js
• Express
• MongoDB
• Mongoose
• Mocha
• Chai
• Joi
• Solidity
• Hardhat
• helmet
• jest
• ReactJS