ServiceBounty

Bounty system for consensys developer certification project for Benjamin Brown.

Prereqs

npm install -g ganache-cli

npm install -g truffle

npm install --save vort_x vort_x-components

Setting up

In root folder, make sure all packages are installed

npm install

Start ganache ganache-cli -p 8545 -b 1

Compile and migrate smart contracts

truffle compile

truffle migrate --reset

Start dev server

npm start

Design Pattern Decisions

I created a Bounty.sol base class for a bounty. BountyHub.sol acts as a container for campaigns and provides some adminstrative pass-through functionality.

For the front end, I am using ReactJS and a new library I came across called Vortex. It has built in functionality to bind smart contract data to front end components, which allow for live updates on the front end when information is updated in the smart contracts. For example, the front end will notify the user whenever certain events occur like:

Contract loaded
Certain solidity Events fired
Transactions success and failure
Transaction confirmations
Changes to View/Contants in smart contracts will update the front end immediately

Design thoughts

Given another look at it in the future, I may prefer to move more of the verification of the process/states into the Bounty.sol contract instead of locating those functions in the hub. I would like to implement contract interfaces toward some standard of smart contract bounties, since in the future a unified bounty standard could allow interoperability between bounty management platforms.

For the states of the bounty, I could have used an ENUM or other common pattern to better represent the state flow.

Avoiding Common Attacks

I took time to review code for common attacks including re-entrancy, overflow/underflow, and various race conditions based on the current knowledge from Consensys and other independent solidity resources. I have avoided using tx.origin and have made sure that sending money to bounty takers requires verification inside the bounty contract itself (which holds the funds)

Tests

I have tested nearly every core function in both BountyHub.sol and Bounty.sol using mocha / truffle for testing. These smoke tests . In the future I would add closer to the metal unit tests as solidity tests.

For the most part, I tested the initiation/completion/verification process against the emitted event logs.