README.md

Star Notarization on Blockchain

A Star Registry Service that allows users to claim ownership of their favorite star in the night sky.

Implementations in this project.

Create a Blockchain dataset that allow you to store a Star

• The application will persist the data (using LevelDB).
• The application will allow users to identify the Star data with the owner.

Create a Mempool component

• The mempool component will store temporal validation requests for 5 minutes (300 seconds).
• The mempool component will store temporal valid requests for 30 minutes (1800 seconds).
• The mempool component will manage the validation time window.

Create a REST API that allows users to interact with the application.

• The API will allow users to submit a validation request.
• The API will allow users to validate the request.
• The API will be able to encode and decode the star data.
• The API will allow be able to submit the Star data.
• The API will allow lookup of Stars by hash, wallet address, and height.

Tech & Dependencies

• Node.js - Node.js® is a JavaScript runtime built on Chrome's V8 JavaScript engine.
• Express.js - Fast, unopinionated, minimalist web framework for Node.js
• Crypto.js - JavaScript library of crypto standards.
• LevelDb - Fast & simple storage - a Node.js-style LevelDB wrapper.
• Bitcoin.js - A javascript Bitcoin library for node.js and browsers.
• Body-parser - Node.js body parsing middleware
• Compression - Node.js compression middleware
• Postman - Postman Makes API Development Simple.
• Electrum Wallet - Electrum Bitcoin Wallet

Installation

Notary Blockchain requires Node.js v4+ to run.

Install the dependencies and start the server.

$ cd NotaryBlockchain
$ npm install
$ node index

The node server will be deployed to http://localhost:8000

Download and install Electrum Wallet to create your bitcoin wallet.

Get your bitcoin address from Electrum Wallet.

Now use Postman to interact with the API.

POST

Request new address validation. Use POST at http://localhost:8000/requestValidation

Copy message from the Output JSON as below:

"message": "1BLDemo8Wx1yP3TBMUvjdBHqtRMWDUHSMv:1542358724640:starRegistry",

Use Electrum Wallet to Sign this message with your bitcoin address.

Copy the the generated signature and use POST to validate Signature at http://localhost:8000/message-signature/validate.

The JSON should return

"messageSignature": "valid"

Now to register your stars please visit Skymap. Find your favorite star and double click to view its co-ordinates.

We need these co-ordinates for registration with a story (Only ASCII text) you want to write about your star. Story has maximum limit of 500 bytes.

• RA = Right Ascension
• DEC = Declination
• MAG = Magnitude
• CON = Constellation

Use POST to send this JSON request to register your star with address parameter at http://localhost:8000/block

{
	"address" : "1BLDemo8Wx1yP3TBMUvjdBHqtRMWDUHSMv",
	"star" : {
		"ra" : "17h41m",
		"dec" : "-40°06",
		"mag" : "7.50",
		"con" : "Scorpius",
		"story" : "From Pune Cr 343 is not observable it will reach its highest point in the sky during daytime and is no higher than 6 degrees above the horizon at dusk."
	}
}

In the output you will find the story written has been hex encoded.

"story": "46726f6d2050756e6520437220333433206973206e6f74206f627365727661626c652069742077696c6c20726561636820697473206869676865737420706f696e7420696e2074686520736b7920647572696e672064617974696d6520616e64206973206e6f20686967686572207468616e203620646567726565732061626f76652074686520686f72697a6f6e206174206475736b2e"

GET

Get Block by height parameter. http://localhost:8000/block/{$height}

Get Block by address parameter http://localhost:8000/stars/address:address

Get Block by hash value parameter http://localhost:8000/stars/hash:hash