Project 4: Build a Private Blockchain Notary Service

Project created as an assignment for Udacity BlockChain Developer Nanodegree Program - Project 4. RESTful API using the Hapi.js Node.js framework which interfaces with the private blockchain. The package JOI was used to support input validation and Boom was used for http code handling.

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

Prerequisites

To run locally, this software requires node (version 8 or above) up and running

Installing

A step by step to get it running

Clone the project from github

git clone https://github.com/bsgiovanini/private_block_chain.git

Install nodemon global module

npm install -g nodemon

Install all dependencies of npm

npm install

Running

Run this command on bash and a server will start at port 8000 with 10 blocks already added to the chain.

npm start

Blockchain ID validation routine

Web API POST endpoint to validate request with JSON response

To validate the request, access it via the POST method (using Postman or Curl), specifying a text as a raw payload. If payload is not informed, a message of "Invalid Input" will be returned from the POST request. Use the URL for the endpoint:

http://localhost:8000/requestValidation

Example of a valid request payload:

{ "address":"19xaiMqayaNrn3x7AjV5cU4Mk5f5prRVpL" }

Web API POST endpoint validates message signature with JSON response

To validate the signature, access it via the POST method (using Postman or Curl), specifying a text as a raw payload. If payload is not informed, a message of "Invalid Input" will be returned from the POST request. Use the URL for the endpoint:

http://localhost:8000/message-signature/validate

Example of a valid request payload:

{
   "address":"19xaiMqayaNrn3x7AjV5cU4Mk5f5prRVpL",
   "signature":"H8K4+1MvyJo9tcr2YN2KejwvX1oqneyCH+fsUL1z1WBdWmswB9bijeFfOfMqK68kQ5RO6ZxhomoXQG3fkLaBl+Q="
}

Star registration Endpoint

Submiting a new Block to the chain (POST)

After validation It is possible to post a block. Access it via the POST method (using Postman or Curl), specifying a text as a raw payload. If payload is not informed or its address was not validated, an error message will be returned from the POST request

http://localhost:8000/block/

Valid payload example

{
    "address": "19xaiMqayaNrn3x7AjV5cU4Mk5f5prRVpL",
    "star": {
                "dec": "68° 52' 56.9",
                "ra": "16h 29m 1.0s",
                "story": "Found star using https://www.google.com/sky/"
            }
}

Star Lookup

Get Star block by hash with JSON response

Use the URL:

http://localhost:8000/stars/hash:{HASH}

Example:

http://localhost:8000/stars/hash:4639e23e3027a287a3512d6c86bb43191634d8083c1ae2e458fc45dd3987feac

Get Star block by wallet address (blockchain identity) with JSON response

Use the URL:

http://localhost:8000/stars/address:{ADDRESS}

Example:

http://localhost:8000/stars/address:1J2vezczmV3U7rdzG9XdmQjfzUFpWg6zfJ

Get star block by star block height with JSON response

To get a specific block, access it via the GET method

http://localhost:8000/block/{height}

Example

http://localhost:8000/block/3