General Purpose Blockchain

General Purpose Blockchain I have created in Python as part of a Blockchain course.

Required

Python 3.6

Flask: install in terminal pip install Flask==0.12.2

Quickstart guide: https://flask.palletsprojects.com/en/1.0.x/quickstart/

Postman HTTP Client https://www.getpostman.com

Libraries

• datetime - needed for time stamping blocks in Unix time timestamp
• hashlib - used to hash the blocks
• json - used to encode the blocks before they are hashed
• Flask - Flask class from the flask library used to create a web application
• jsonify - used to return messages in postman when requesting the state of the blockchain or key info of the block that has been mined

Requests

Requests used to query the blockchain in Postman once the application is running on Flask:

Get Chain

• Queries the current state of blockchain: http://127.0.0.1:5000/get_chain

Mine Block

• Mines a new block: http://127.0.0.1:5000/mine_block

Is Chain Valid

• Checks if Blockchain is valid i.e. if all previous hashes match with corresponding blocks: http://127.0.0.1:5000/is_valid