node.py

from flask import Flask, jsonify, request, send_from_directory
from wallet import Wallet
from flask_cors import CORS
from blockchain import Blockchain
import ast

app = Flask(__name__)
CORS(app)


@app.route('/', methods = ['GET'])
def get_node_ui():
 return send_from_directory('ui', 'node.html')


@app.route('/network', methods = ['GET'])
def get_network_ui():
 return send_from_directory('ui', 'network.html')


@app.route('/wallets', methods= ['GET'])
def wallets():
 return send_from_directory('ui', 'wallets.html')

@app.route('/wallet', methods=['POST'])
def create_keys():
 wallet.create_keys()
 if wallet.save_keys():
 global blockchain
 blockchain = Blockchain(wallet.public_key, port)
 response = {
 'public_key': wallet.public_key,
 'private_key': wallet.private_key,
 'funds': blockchain.get_balance()
 }
 return jsonify(response), 201
 else:
 response = {
 'message': 'Saving keys failed'
 }
 return jsonify(response), 500


@app.route('/wallet', methods=['GET'])
def load_keys():
 if wallet.load_keys():
 global blockchain
 blockchain = Blockchain(wallet.public_key, port)
 response = {
 'public_key': wallet.public_key,
 'private_key': wallet.private_key,
 'funds': blockchain.get_balance()
 }
 return jsonify(response), 201
 else:
 response = {
 'message': "No wallet to load"
 }
 return jsonify(response), 500


@app.route('/show-wallets', methods=["GET"])
def show_wallets():
 wallets = wallet.show_keys()
 print("WALLETS", wallets)
 public_keys = ""
 for line in wallets:
 print("line",line)
 print('\n')
 keys = ast.literal_eval(line)
 public_keys = keys['public']
 print("key",public_keys)
 print('\n')
 response = {
 'wallets': wallets,
 'message': 'Done'
 }
 return jsonify(response), 200


@app.route('/balance', methods= ['Get'])
def get_balance():
 balance = blockchain.get_balance()
 if balance != None:
 response = {
 'message': 'Balance fetched',
 'funds': balance
 }
 return jsonify(response), 201
 else:
 response = {
 'message': 'Adding a block failed',
 'wallet_set_up': wallet.public_key != None
 }
 return jsonify(response), 500


@app.route('/broadcast-transaction', methods=['POST'])
def broadcast_transaction():
 values = request.get_json()
 if not values:
 response = {
 'message': 'No data found'
 }
 return jsonify(response), 400
 required = ['sender', 'recipient', 'amount', 'signature']
 if not all(key in values for key in required):
 response = {
 'message': 'Some data is missing.'
 }
 return jsonify(response), 400
 success = blockchain.add_transaction(values['recipient'], values['sender'], values['signature'], values['amount'], is_receiving=True)
 if success:
 response = {
 'message': 'Successfully added transaction.',
 'transaction': {
 'sender': values['sender'],
 'recipient': values['recipient'],
 'amount': values['amount'],
 'signature': values['signature']
 }
 }
 return jsonify(response), 201
 else:
 response = {
 'message': 'Failed in creating a transaction'
 }
 return jsonify(response), 500


@app.route('/broadcast-block', methods=['POST'])
def broadcast_block():
 values = request.get_json()
 if not values:
 response = {
 'message': 'No data found.'
 }
 return jsonify(response), 400
 if 'block' not in values:
 response = {
 'message': "Some data is missing."
 }
 return jsonify(response), 400
 block = values['block']
 if block['index'] == blockchain.chain[-1].index + 1:
 if blockchain.add_block(block):
 response = {'message': 'Block Added'}
 return jsonify(response), 201
 else:
 response = {'message': 'Block seems invalid.'}
 return jsonify(response), 409
 elif block['index'] > blockchain.chain[-1].index:
 response = {
 'message': 'Blockchain seems to differ from local blockchain.'
 }
 blockchain.resolve_conflicts = True
 return jsonify(response), 200
 else:
 response = {
 'message': 'Blockchain seems to be shorter, block not added.'
 }
 return jsonify(response), 409


@app.route('/transaction', methods= ['POST'])
def add_transaction():
 if wallet.public_key == None:
 response = {
 'message': 'No wallet set up.'
 }
 return jsonify(response), 400
 values = request.get_json()
 if not values:
 response = {
 'message': 'No data found'
 }
 return jsonify(response), 400
 required_fields = ['recipient', 'amount']
 if not all(field in values for field in required_fields):
 response = {
 'message': 'Required data is missing'
 }
 return jsonify(response), 400
 signature = wallet.sign_transaction(wallet.public_key, values['recipient'], values['amount'])
 success = blockchain.add_transaction(values['recipient'], wallet.public_key, signature, values['amount'])
 if success:
 response = {
 'message': 'Successfully added transaction.',
 'transaction': {
 'sender': wallet.public_key,
 'recipient': values['recipient'],
 'amount': values['amount'],
 'signature': signature
 },
 'funds': blockchain.get_balance()
 }
 return jsonify(response)
 else:
 response = {
 'message': 'Failed in creating a transaction'
 }
 return jsonify(response), 500


@app.route('/mine', methods = ['POST'])
def mine():
 if blockchain.resolve_conflicts == True:
 response = {'message': 'Resolve conflicts first, block not added!'}
 return jsonify(response), 409
 block = blockchain.mine_block()
 if block != None:
 dict_block = block.__dict__.copy()
 dict_block['transactions'] = [tx.__dict__ for tx in dict_block['transactions']]
 response = {
 'message': 'Block added successfully',
 'block': dict_block,
 'funds': blockchain.get_balance()
 }
 return jsonify(response), 201
 else:
 response = {
 'message': 'Adding a block failed',
 'wallet_set_up': wallet.public_key != None
 }
 return jsonify(response), 500


@app.route('/resolve-conflicts', methods=['POST'])
def resolve_conflicts():
 replaced = blockchain.resolve()
 if replaced:
 response = {'message': 'Chain was replaced!'}
 else:
 response = {'message': 'Local chain kept!'}
 return jsonify(response), 200


@app.route('/transactions', methods= ['GET'])
def get_open_transactions():
 trasactions = blockchain.get_open_transactions()
 dict_transactions = [tx.__dict__ for tx in trasactions]
 response = {
 'message': 'Feteched open transactions',
 'transactions': dict_transactions
 }
 return jsonify(response), 200

@app.route('/chain', methods=['GET'])
def get_chain():
 chain_snapshot = blockchain.chain
 dict_chain = [block.__dict__.copy() for block in chain_snapshot]
 for dict_block in dict_chain:
 dict_block['transactions'] = [tx.__dict__ for tx in dict_block['transactions']]
 return jsonify(dict_chain), 200

@app.route('/node', methods= ['POST'])
def add_node():
 values = request.get_json()
 if not values:
 response = {
 'message': 'No data attached.'
 }
 return jsonify(response), 400
 if 'node' not in values:
 response = {
 'message': 'No node data found.'
 }
 return jsonify(response), 400
 node = values.get('node')
 blockchain.add_peer_node(node)
 response = {
 'message': 'Node added successfully',
 'all_nodes': blockchain.get_peer_nodes()
 }
 return jsonify(response), 201


@app.route('/node/<node_url>', methods= ['DELETE'])
def remove_node(node_url):
 if node_url == '' or node_url == None:
 response = {
 'message': "No data attached"
 }
 return jsonify(response), 400
 if node_url not in blockchain.get_peer_nodes():
 response = {
 'message': 'Node not present'
 }
 return jsonify(response), 400
 blockchain.remove_peer_node(node_url)
 response = {
 'message': 'Node removed',
 'all_nodes': blockchain.get_peer_nodes()
 }
 return jsonify(response), 201


@app.route('/nodes', methods= ["GET"])
def get_nodes():
 nodes = blockchain.get_peer_nodes()
 response = {
 'message': 'All peer nodes',
 'all_nodes': nodes
 }
 return jsonify(response), 201

if __name__ == '__main__':
 from argparse import ArgumentParser
 parser = ArgumentParser()
 parser.add_argument('-p', '--port', type=int, default=5000)
 args = parser.parse_args()
 port = args.port
 wallet = Wallet(port)
 blockchain = Blockchain(wallet.public_key, port)
 app.run(host='0.0.0.0', port=port)