victor-wei126 / acala-solidity

Solidity Smart Contract Challenge

This is my attempt to complete the ERC20 upgradeable smart contract. NOTE: This is my initial attempt, and is not complete. The things I have gotten stuck on and am still working on are:

1. The contract currently returns 100% of ETH, not 90%. I will need to figure out how to use fractional values in solidity, as math with decimal values like 0.9 is more complicated.
2. The contract does not have a kill switch to turn off upgradeability. Since I am using OZ's upgradeable proxy contract, my immediate thought is to have a function and a flag that indicates if upgradeability is has been turned on or off. If off, then the transaction calling for an upgrade should fail. Since the upgradeability logic lies in the proxy contract, I may need to dig in to OZ's implementation.

Most of the relevant code for this challenge was done in contracts/. The migrations/ folder contains nothing special, besides using the OZ functions from their upgradeable plugin. Finally, the tests/ directory contains some pretty in-depth testing of the contracts I did before deploying to Kovan.

Transaction deploys smart contracts:

https://kovan.etherscan.io/tx/0x225eb3b42738494f2f074ae27296c36d3adcab73944de1c01a71a92d3d924665 https://kovan.etherscan.io/tx/0xf90abec50e8126966cfabf0b126dd903c877822318a97210ce57969064f08a48 (deploy proxy)

Transaction sends ETH to mint ERC20 token:

https://kovan.etherscan.io/tx/0xaaa4d2c5a25bd391eeeb0c0499a09c3a481974d9290af7f9c16a2001727ae75e

Transaction performs upgrade:

https://kovan.etherscan.io/tx/0xa2f0964cf3bfaf753433e17281b6bf97734a66685f026fd227760df7149a67f5

Transaction performs kill switch:

TODO

Transaction that burn ERC20 token and receive ETH:

https://kovan.etherscan.io/tx/0x92077377b81606536407c070081b3b9c4ab76c0a37eac0c785985f85c53a8d52