Ethereum-Payment-Splitter

An Ether Payment Splitter for musical royalties. It's a web based DApp test project using Solidity & Javascript (including the Web3 library).

Important Note

The web3 library used here has had a vulnerabilty found in it which hasn't been patched yet - WS-2019-0097 (web3/web3.js#2739). This isn't relevant to the current version of the project, however if you use web.js and implement the wallet.save method (https://web3js.readthedocs.io/en/v1.2.0/web3-eth-accounts.html#wallet-save), which stores the wallet encrypted and as a string in local storage, you should be aware that it's vulnerable to Insecure Credential Storage attacks (once a user enters a password to load the wallet from storage, the private key will remain available and this leaves the private key vulnerable to XSS).

Overview

The current functionality consists of the following::

1. Adding recipients and their relative royalties of a song (name, address, % of royalties).
2. Depositing and sending them these shares based on a certain deposited amount for the song.

Do not use with real funds without a proper audit.

Required Installations

1. NPM (https://www.npmjs.com/get-npm)
2. Truffle, using NPM (https://www.truffleframework.com/truffle) by typing npm install truffle -g
3. Ganache (https://www.truffleframework.com/ganache)
4. MetaMask - add it to your browser (https://metamask.io) and create a password

You should understand the basic functionality and purpose of these tools before moving forward.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes:

1. Start Ganache and make sure that it's configured to localhost port 8545
2. Go to the project's local folder
3. Type truffle migrate --reset --compile-all in order to recompile and upload the Solidity contracts to the local testnet (Ganache)
4. Type truffle console to enter Truffle's Web3 console
5. Type AppStein.new().then( result => {new_instance = result}) in order to save the information from the contract into a variable you can reference using a Javascript promise
6. Check the deployed contract's address by typing new_instance.address
7. Make sure that the address is the same in line 160 in the AppStein.html file which is located in the project folder (0x5227e903028a5ca06c029afe269053fd146f4540). If not, update the correct address.
8. Verify that the ABI in line 70 in the AppStein.html file is the the value that resides under the /build/contracts/AppStein.JSON file. Another implementation is possible for this, as suggested here, among other places (reading the JSON contents dynamically instead of entering the static ABI hardcoded value): https://ethereum.stackexchange.com/questions/38828/what-is-the-best-way-to-get-the-json-abi-after-deploying-a-contract-with-truffle.

You should now be ready to go!

Using the DApp

1. Open the AppStein.html file, located in the project folder
2. Open Metamask and login
3. Configure MetaMask to run on your localhost network on port 8545 (using the dropdown menu in the main screen).
4. Configure MetaMask to use your Ganache account by importing the seed. This is explained here: https://ethereum.stackexchange.com/questions/34287/using-ganache-with-an-existing-metamask-account
5. Add a recipient, an address and a percentage of music royalties. Now press the Add Recipient button.
6. Add a song ID & named and enter an amount of Ether to submit.
7. Submit!
8. The amounts should be transferred in accordance to your specifications.

Quick Guide for Developers

Here is a list of the files holding the logic of the DApp. I made these files as documented as possible.

1. /AppStein.html - Holds the HTML & JavaScript logic.
2. /Contracts/AppStein.sol - Holds the Solidity Logic.
3. /Contracts/Ownable.sol - Holds the Open Zeppelin Ownable contract Solidity logic. 
4. /style.css - Holds the styling & formatting for the html file.
5. /truffle.js and /truffle-config.js - Hold the project's configuration for the network exports & migrations.

Built With

• [NPM] (https://www.npmjs.com/get-npm) - Dependency Management.
• [Ganache] (https://www.truffleframework.com/ganache) - Used to create and manage a local BlockChain tesnet on the localhost.
• [MetaMask] (https://metamask.io) - Used to interact with the DApp using an injected WEB3 interface within the browser.
• [Truffle] (https://www.truffleframework.com/truffle) - Used to compile, migrate the Solidity contract files to the local testnet and interact with the deployed contracts. The truffle network configuration is available in the truffle.js & truffle-config.js files. More on this here: https://truffleframework.com/docs/truffle/reference/configuration
• [Ethereum Blockchain App Platform] (https://www.ethereum.org) - A decentralized platform for smart contracts.

Authors

• Avishai Efrat - Initial work - AvishaiEfrat

Acknowledgments

• Project inspiration and guidence by Chanan Sack.
• README.md structure taken from https://gist.githubusercontent.com/PurpleBooth.
• HTML & JS original structure based on Javascript30's tutorials (www.javascript30.com).
• Background image from https://pixabay.com/en/audio-condenser-microphone-music-1844798 (Creative Commons CC0).

Also Check

• [Open Zeppelin Payment Splitter] (https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/finance/PaymentSplitter.sol) - A payment splitter on the Open Zeppelin GitHub page (a library for secure smart contract development).