/Starmania

Primary LanguageJavaScript

Starmania

I have called this project Starmania. Here are infos about the ERC-721 token I have created:

  • ERC-721 Token Name: Starmania Token
  • ERC-721 Token Symbol: ST

Also, the contract address on the Rinkeby Network:

  • 0x2f88A89cc270b9c0107538bE92460af29D06fC33

See on Rinkeby Etherscan

Finally I have created 4 stars:

  • Star id 1, named Udacity Star, owned by 0xA9e39Ed28cBd782d66Ec76700E5F4B5B2031778C
  • Star id 2, named Toto Star, owned by 0x314ddeAeEB51187cE9833bb9A7bFd1cA898F3b9A
  • Star id 3, named Cam Star, owned by 0xe02Fb45C99D8e5A2F2037a35F4D1b1f2b79062AE
  • Star id 4, named Matt Star, owned by 0xA9e39Ed28cBd782d66Ec76700E5F4B5B2031778C

See Deployment Information below for more information about the deployment on the Rinkeby network.

Demo

Demo

Versions

  • Truffle v5.1.61 (core: 5.1.61)
  • Solidity v0.5.16 (solc-js)
  • Node v12.16.1
  • Web3.js v1.2.9
  • OpenZeppelin v2.1.2

Deployment Information on Rinkeby

   Deploying 'StarNotary'
   ----------------------
   > transaction hash:    0x8f79b7aec12dea7f65392825c9333b04fc52179c4b4d1235cb8dfe317fc4fdeb
   > Blocks: 1            Seconds: 9
   > contract address:    0x2f88A89cc270b9c0107538bE92460af29D06fC33
   > block number:        7892542
   > block timestamp:     1610615873
   > account:             0xA9e39Ed28cBd782d66Ec76700E5F4B5B2031778C
   > balance:             0.97734516
   > gas used:            1997884 (0x1e7c3c)
   > gas price:           10 gwei
   > value sent:          0 ETH
   > total cost:          0.01997884 ETH

Preliminary Notes

Please note the following:

As an example, this allows us to test reversion if a star does not exist:

await truffleAssert.reverts(
    instance.lookUptokenIdToStarInfo(imaginaryStarId),
    "This star does not exist."
    );

  • To exchange stars, it was suggested to use the _transferFrom method which is unsafe, I have followed the instructions. It seems it would have been a good idea to use safeTransferFrom instead to transfer ownership of the tokens. Most importantly, it may have been preferable to have approval from the owner before proceeding with the transfer. Hence _transferFrom is quite dangerous, and at least transferFrom should have been used. To do this, we would have had to create a function to approve the transfer of a star for a period of time. Once granted approval, the transfer can be started by the other owner.

  • When writing tests, I have created 2 new test cases to ensure revert happens in critical security scenarios i.e. the unhappy paths. These are it('does not let a user exchange a star he/she does not own', .. and it('does not let a user transfer a star he/she does not own', ..).

  • I am using Port 8545 locally