server.py

import hashlib
import json
from textwrap import dedent
from time import time
from uuid import uuid4
from flask import Flask,jsonify,request
from blockchain import Blockchain

app =Flask(__name__)
node_identifier = str(uuid4()).replace('-','')

blockchain = Blockchain()

@app.route('/mine',methods=['GET'])
def mine():
	if blockchain.current_transactions == []:
		response = {"message":"No transactions to mine"}
		return jsonify(response),200
	last_block = blockchain.last_block
	last_proof = last_block['proof']
	proof=blockchain.proof_of_work(last_proof)
	blockchain.new_transaction(sender="0",recipient=node_identifier,amount=1)
	previous_hash = blockchain.hash(last_block)
	block = blockchain.new_block(proof,previous_hash)

	response = {
	"message":"Block verified and added",
	"index":block["index"],
	"transactions":block["transactions"],
	"proof":block["proof"],
	"previous_hash": block["previous_hash"]
	}
	return jsonify(response),200

@app.route('/transactions/new',methods=['POST'])
def new_transaction():
	values = request.get_json()
	required = ['sender','recipient','amount']
	if not all(k in values for k in required):
		return "Missing Values",400
	index = blockchain.new_transaction(values['sender'],values['recipient'],values['amount'])
	response = {"message":"Transaction submitted for mining"}
	return jsonify(response),201

@app.route('/chain',methods=['GET'])
def full_chain():
	response = {
	'chain':blockchain.chain,
	'length':len(blockchain.chain),
	}
	return jsonify(response),200

@app.route('/nodes/register', methods=['POST'])
def register_nodes():
    values = request.get_json()

    nodes = values.get('nodes')
    if nodes is None:
        return "Error: Please supply a valid list of nodes", 400

    for node in nodes:
        blockchain.register_node(node)

    response = {
        'message': 'New nodes have been added',
        'total_nodes': list(blockchain.nodes),
    }
    return jsonify(response), 201


@app.route('/nodes/resolve', methods=['GET'])
def consensus():
    replaced = blockchain.resolve_conflicts()

    if replaced:
        response = {
            'message': 'Our chain was replaced',
            'new_chain': blockchain.chain
        }
    else:
        response = {
            'message': 'Our chain is authoritative',
            'chain': blockchain.chain
        }

    return jsonify(response), 200

if __name__=='__main__':
	app.run(host='0.0.0.0',port=5000)