CrowdCoin

Allows you to create and manage campaigns in Rinkeby network using ethereum smart contracts.

Technology stack:

• Truffle - ( development framework for dapps based on the Ethereum blockchain: https://truffleframework.com/),
• Ganache - ( A personal blockchain for Ethereum development that can be used to deploy contracts, develop applications, and run tests: https://truffleframework.com/ganache),
• Solidity - (contract-oriented programming language for writing smart contracts: https://solidity.readthedocs.io/en/v0.4.24/),
• Web3.js - (Ethereum JavaScript API: https://github.com/ethereum/web3.js/)
• Truffle Contract -(Better Ethereum contract abstraction, for Node and the browser):https://www.npmjs.com/package/@truffle/contract
• MetaMask - (A browser plugin which allows users to make transactions to Ethereum or other networks through browsers, eliminating the need for dedicated user interfaces for Ethereum or other networks: https://chrome.google.com/webstore/detail/metamask/nkbihfbeogaeaoehlefnkodbefgpgknn?hl=en)
• OpenZeppelin Contracts - OpenZeppelin Contracts is a library for secure smart contract development: https://github.com/OpenZeppelin/openzeppelin-contracts
• NodeJS - (An open source and cross-platform runtime environment for executing JavaScript code outside of a browser: https://nodejs.org/en/),
• Semantic UI - User Interface
• Next JS - Server Rendered Apps

Pre-Requisites

You need to install metamask browser extension and create an account.

Once your account is ready, you need to add some ether balance using Rinkeby Authenticated Faucet.

In the absence of metamask, the project will fallback to using Infura node to access Rinkeby network.

Set Up

Install truffle

• Run the command npm install -g truffle
• Git clone the E-cert-Dapp repo
• Cd into the directory and run yarn install
• Run yarn run compile to compile the smart contract
• Run yarn run migrate to migrate the contract. truffle deploy is an alias for truffle migrate. They both do the same thing.
• Run yarn run console to interact with the smart contract on the ganache ethereum blockchain

Install Ganache

• Go to https://truffleframework.com/ganache and download a version dedicated to your operating system.
• Install by a double click, then run.
• Ganache runs with default values which should be the same or similar to these on-screen. The crucial part is a section defining RPC Server.
• Leave it running.

Install Nodejs

• To download Nodejs, navigate to navigate to https://nodejs.org/en/download/ and click the version that suits your machine
• After downloading it, click the installer to get it installed on your machine
• Verify installation by running the command on your CLI node -v
• You can use npm or yarn for package management

Testing Results

• Open a terminal and run: truffle test or yarn run test

Test Coverage Results

• Open a terminal and run: truffle run coverage or yarn run coverage

Contract deployment gas cost on local network - Ganache

• Open a terminal and run: truffle run migrate or yarn run migrate

Contract deployment gas cost on ropsten network - testnet on infuria

• Open a terminal and run: truffle run ropsten or yarn run ropsten

Contract deployment gas cost fee on ropsten etherscan explorer

• Open a terminal and run: truffle run ropsten or yarn run ropsten

• link: https://ropsten.etherscan.io/address/0x0268B3D69FbD4b83F2a51E579ed0953f7a8775E2

Campaign Contract Graph

• Use Solidity Visual Developer to generate the graph for the contract

Campaign Factory Contract Graph

• Use Solidity Visual Developer to generate the graph for the contract

Campaign Contract UML Diagram

• Use Solidity Visual Developer to generate the UML with PlantUML embedded

Campaign Contract UML Diagram

• Use Solidity Visual Developer to generate the UML with PlantUML embedded

Smart Contract

Campaign contract is deployed at address 0x2280cB3780CACe8da81dF119f9af16F3aF73c02A and is available inside the contracts folder.

Our app will interact with the deployed contract to create campaigns.

Running the project

npm run dev

Go to browser at address http://localhost:3000 to access the web page.

Next JS performs server side rendering of the pages and hot reloading as you make any changes to the code.

Operations

Create Campaign

You can create a campaign by specifying a minimum contribution required.

Once the campaign is created, you become the manager of the campaign and will be able to create requests which needs to be approved by the contributors.

Any user who contributes below the requirement for the campaign will have their transaction rejected.

View Campaign

Shows details of the campaign such as address of the account which created the campaign, minimum contribution required, campaign balance, number of people who have donated for the campaign and number of requests created by the manager.

Contribute

Allows you to contribute to the campaign.

View Requests

List the requests created by the manager for the campaign.

Contributors can approve the requests.

Once the approval criteria is met, the manager can finalize the request for payment to the recipient.

Add Request

Manager of a campaign can create a request which will be fulfilled by the recipient.

Once more than 50% of the campaign contributors approve the request, the manager can finalize the payment to the vendor.

• Credit: Stephen Grider course on Udemy