University Of Karachi - Department Of Computer Science

Final Year Project (MCS 2017-2018)
Project Title: Bitcoin Blockchain Application
Supervisor: Sir Khalid Jamal
Members: Riaz Ahmed, Ayesha Qureshi

Prequisites

1. Install Node LTS 8.x.x (https://nodejs.org/en/download/)
2. Install NPM (if you have installed node it comes with NPM)
3. Install Application dependencies npm install
4. A text editor (sublime preferred) (https://www.sublimetext.com/3)
5. Postman (https://www.getpostman.com/downloads/)

How To Interact With API

Please follow the steps given below, do it in sequence.

1. Start server

Run 5 instances on different ports, all should be up and running

npm run node_1
npm run node_2
npm run node_3
npm run node_4
npm run node_5

2. Decentralise

Register all nodes together to make a decentralised network

URL: http://localhost:3001/register-and-broadcast-node
METHOD: POST
PAYLOAD:

{
	"newNodeUrl": "http://localhost:3002"
}

{
	"newNodeUrl": "http://localhost:3003"
}

{
	"newNodeUrl": "http://localhost:3004"
}

{
	"newNodeUrl": "http://localhost:3005"
}

3. Transaction

Make a transaction on any node, it will be broadcasted to all other nodes as well

URL: http://localhost:3001/transaction/broadcast
METHOD: POST
PAYLOAD:

{
	"amount": 600,
	"sender": "JENSDHFAS7DF7SADFY72",
	"recipient": "SALDFJALKSFDJ82YE"
}

4. Mine

Mine a new block on any node, and it will be broadcasted to all other nodes as well

URL: http://localhost:3001/transaction/mine

5. Consensus

Consensus will validate the chain, to make it work shutdown any node let's say at port 3005 and make some transactions on any other node and start the server at port 3005 again and again register it with any other node. So blockchain at port 3005 does not contain the valid chain. In order to validate do the following:
URL: http://localhost:3005/consensus

6. Block Explorer

You can see the transaction details for each block by using BlockHash, TransactionID, Address URL: http://localhost:3005/block-explorer