1 files changed, 0 insertions, 288 deletions
diff --git a/blockchain.py b/blockchain.py
deleted file mode 100644
index 8aab178..0000000
--- a/blockchain.py
+++ /dev/null
@@ -1,288 +0,0 @@
-import hashlib
-import json
-import re
-import plyvel
-from time import time
-from urllib.parse import urlparse
-from uuid import uuid4
-
-import requests
-from flask import Flask, jsonify, request
-
-
-class Blockchain:
-    def __init__(self):
-        self.database = plyvel.DB("database/", create_if_missing=True)
-        self.current_message = []
-        self.chain = []
-        self.nodes = set()
-
-        # create first block (genesis)
-        self.new_block(previous_hash='1', proof=100)
-
-    def register_node(self, address):
-        """
-        registers a new node
-        :param address: IP of node
-        """
-
-        if re.match(r'[0-9]+(?:\.[0-9]+){3}:[0-9]+', address):
-            parsed_url = urlparse(address)
-            if parsed_url.netloc:
-                self.nodes.add(parsed_url.netloc)
-            elif parsed_url.path:
-                self.nodes.add(parsed_url.path)
-            else:
-                raise ValueError('Invalid URL')
-        else:
-            raise ValueError('Invalid URL')
-
-    def valid_chain(self, chain):
-        """
-        check if a block is valid
-        :param chain: A blockchain
-        :return: True if valid, False if not
-        """
-
-        last_block = chain[0]
-        current_index = 1
-
-        while current_index < len(chain):
-            block = chain[current_index]
-            print(f'{last_block}')
-            print(f'{block}')
-            print("\n-----------\n")
-            # check hash
-            last_block_hash = self.hash(last_block)
-            if block['previous_hash'] != last_block_hash:
-                return False
-
-            # check proof
-            if not self.valid_proof(last_block['proof'], block['proof'], last_block_hash):
-                return False
-
-            last_block = block
-            current_index += 1
-
-        return True
-
-    def resolve_conflicts(self):
-        """
-        Resolves conflict by replacing if other chain is longer
-        :return: true if replaced
-        """
-
-        neighbours = self.nodes
-        new_chain = None
-
-        # only get the ones which are longer than own
-        max_length = len(self.chain)
-
-        # get all chains from nodes and verify
-        for node in neighbours:
-            response = requests.get(f'http://{node}/chain')
-
-            if response.status_code == 200:
-                length = response.json()['length']
-                chain = response.json()['chain']
-
-                # check if longer and valid
-                if length > max_length and self.valid_chain(chain):
-                    max_length = length
-                    new_chain = chain
-
-        # replace if other is longer
-        if new_chain:
-            self.chain = new_chain
-            return True
-
-        return False
-
-    def new_block(self, proof, previous_hash):
-        """
-        create new block in blockchain
-        :param proof: The proof given by the Proof of Work algorithm
-        :param previous_hash: Hash of previous Block
-        :return: New Block
-        """
-
-        block = {
-            'index': len(self.chain) + 1,
-            'timestamp': time(),
-            'message': self.current_message,
-            'proof': proof,
-            'previous_hash': previous_hash or self.hash(self.chain[-1]),
-        }
-
-        # reset the list of messages
-        self.current_message = []
-
-        self.chain.append(block)
-        self.database.put(b'key', b'value')
-        return block
-
-    def new_message(self, sender, recipient, message):
-        """
-        creates a new message (gets into next mined block)
-        :param sender: Address of the Sender
-        :param recipient: Address of the Recipient
-        :param message: Message
-        :return: The index of the Block that will hold this message
-        """
-        self.current_message.append({
-            'sender': sender,
-            'recipient': recipient,
-            'message': message,
-        })
-
-        return self.last_block['index'] + 1
-
-    @property
-    def last_block(self):
-        return self.chain[-1]
-
-    @staticmethod
-    def hash(block):
-        """
-        hash the block (sha256)
-        :param block: Block
-        """
-
-        # sort dict
-        block_string = json.dumps(block, sort_keys=True).encode()
-        return hashlib.sha256(block_string).hexdigest()
-
-    def proof_of_work(self, last_block):
-        """
-        create proof
-        :param last_block: <dict> last Block
-        :return: <int>
-        """
-
-        last_proof = last_block['proof']
-        last_hash = self.hash(last_block)
-
-        proof = 0
-        while self.valid_proof(last_proof, proof, last_hash) is False:
-            proof += 1
-
-        return proof
-
-    @staticmethod
-    def valid_proof(last_proof, proof, last_hash):
-        """
-        Validates the Proof
-        :param last_proof: <int> Previous Proof
-        :param proof: <int> Current Proof
-        :param last_hash: <str> The hash of the Previous Block
-        :return: <bool> True if correct, False if not.
-        """
-
-        guess = f'{last_proof}{proof}{last_hash}'.encode()
-        guess_hash = hashlib.sha256(guess).hexdigest()
-        return guess_hash[:4] == "0000"
-
-
-# start node
-application = Flask(__name__)
-
-# generate node ID
-node_identifier = str(uuid4()).replace('-', '')
-
-# create blockchain
-blockchain = Blockchain()
-
-
-@application.route('/mine', methods=['GET'])
-def mine():
-    # run the proof of work algorithm to get the next proof
-    last_block = blockchain.last_block
-    proof = blockchain.proof_of_work(last_block)
-    blockchain.new_message(
-        sender="0",
-        recipient=node_identifier,
-        message="",
-    )
-
-    # forge by adding block to chain
-    previous_hash = blockchain.hash(last_block)
-    block = blockchain.new_block(proof, previous_hash)
-
-    response = {
-        'answer': "New Block Forged",
-        'index': block['index'],
-        'message': block['message'],
-        'proof': block['proof'],
-        'previous_hash': block['previous_hash'],
-    }
-    return jsonify(response), 200
-
-
-@application.route('/message/new', methods=['POST'])
-def new_message():
-    values = request.get_json()
-
-    # check POST fields
-    required = ['sender', 'recipient', 'message']
-    if not all(k in values for k in required):
-        return 'Missing values', 400
-
-    # new message to blockchain
-    index = blockchain.new_message(
-        values['sender'], values['recipient'], values['message'])
-
-    response = {'answer': f'Message will be added to Block {index}'}
-    return jsonify(response), 201
-
-
-@application.route('/chain', methods=['GET'])
-def full_chain():
-    response = {
-        'chain': blockchain.chain,
-        'length': len(blockchain.chain),
-    }
-    return jsonify(response), 200
-
-
-@application.route('/nodes/list', methods=['GET'])
-def getNodeList():
-    response = {
-        'total_nodes': list(blockchain.nodes)
-    }
-    return jsonify(response), 200
-
-
-@application.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 = {
-        'answer': 'New nodes have been added',
-        'total_nodes': list(blockchain.nodes),
-    }
-    return jsonify(response), 201
-
-
-@application.route('/nodes/resolve', methods=['GET'])
-def consensus():
-    replaced = blockchain.resolve_conflicts()
-
-    if replaced:
-        response = {
-            'answer': 'Our chain was replaced',
-            'new_chain': blockchain.chain
-        }
-    else:
-        response = {
-            'answer': 'Our chain is authoritative',
-            'chain': blockchain.chain
-        }
-
-    return jsonify(response), 200