hello2all/bcnd-p5-decentralized-star-notary

Blockchain ND Project 5 - Decentralized Star Notary

Introduction

This project provides a decentralized star notary service on the Ethereum block chain, following the ERC721 standard. Users can claim a star, share a star story and sale a star to others.

This project is written in Solidity and with unit tests using Truffle framework.

Deployment

This service has already been deployed on the Rinkeby Ethereum blockchain, the contract can be found with the following contract address or here on Etherscan:

0x054617Ba4CCaF4C249AFDb53737B9B3d90e8Fcb0

The contract creation transaction has is:

0x3169957bd066310b8c045db203ebfea77de3f469e5313631cfaef7b4323ca881

An star has been claimed with token ID 1, and put up for sale. The star creation transaction hash is:

0xa8edb0b26439e1794bbbb1d35be208e4092390f59246a8e2f8ff7b7247cd55c5

The current owner of this star is:

0x23d4993DdB6041d0581166Bdc7d34ae7bB71C755

Notary Service Client

A web based client is provided for claiming new stars as well as lookup registered stars on the Ethereum blockchain.

Setup

This program relies on MetaMask and npm package manager. To setup the client, run the following commands in the terminal:

npm install http-server
http-server

Then open browser to the page http://localhost:8080.

You need give MetaMask permission to access your account's public information.

Usage

Claim star

A new star can be claimed by a user after key in all required fields. Dec, Mag, and Cent combinations are unique identifiers of a star, thus registering the same star twice will be rejected. Token ID can be any integer number, you can check the availability of an ID using the lookup function below.

Claiming a new star requires payment for execution of the smart contract. Follow the instructions in MetaMask will guide you complete the process. A new star will be transferred to the new owner after successful payment.

Lookup star

Registered stars can be looked up using the Lookup Star button.