Udacity Blockchain Capstone

This is the final project for the Udacity Blockchain Nanodegree program. The project involves minting tokens to represent property titles. zk-SNARKS are leveraged to create a system which can prove the ownership of the property title without revealing specific information of the property.

The tokens are minted and then placed on Opensea for sale or auctions.

Project Resources

Zokrates

Install version 0.4.10 because the latest version produces a contract which doesn't conform to the examples shown during the course

docker run -v /path/to/project/folder:/home/zokrates/code -ti zokrates/zokrates:0.4.10 /bin/bash

Generate New Proof

Compute witness the witness
```
~/zokrates compute-witness -a 9 81
```
Generate proof
```
~/zokrates generate-proof
```
Export verifier
```
~/zokrates export-verifier
```

Deploy to Rinkeby

Create the following files in the eth-contracts folder:

.infuraKey: Your Infura key
.secret: Your MetaMask seed phrase (mnemonic)

And store your infura key and metamask seed phrase in the files listed above.

Run the following command: truffle migrate --reset --network rinkeby

Submit Zokrated Solution And Mint Token

Update config.json with the addresses for Verifier, EmpireHomesERC721Token and SolnSquareVerifier

Switch to the eth-contracts directory on the terminal

Run the following command (submits a new solution with the proof and the token ID provided as arguments): node submit-solution.js ../zokrates/code/square/proof.json 3

Mint the token(mint the token specifying the token ID as an argument): node mint-token.js 3