Merge pull request #29 from se-jaeger/pretty_print_chain

Pretty print chain.

src/blockchain/block.py

@@ -2,6 +2,7 @@
 
 from time import time
 
+from src.utils.utils import colorize
 from src.blockchain.data import Data
 
 
@@ -104,14 +105,15 @@ def __repr__(self) -> str:
 
         """
 
-        block_rep = "Block object with - \n"
-        block_rep += "\tindex:\t\t" + str(self.index) + "\n"
-        block_rep += "\tdata:\t\t" + str(self.data) + "\n"
-        block_rep += "\ttime:\t\t" + str(self.timestamp) + "\n"
-        block_rep += "\tproof:\t\t" + str(self.proof) + "\n"
-        block_rep += "\tprevious hash:\t" + str(self.previous_hash) + "\n"
+        block_representation =  f"\n| {'=' * 80}\n"
+        block_representation += f"| {colorize('index', 'bold')}: \t {str(self.index)} \n"
+        block_representation += f"| {colorize('time', 'bold')}: \t {str(self.timestamp)} \n"
+        block_representation += f"| {colorize('proof', 'bold')}: \t {str(self.proof)} \n"
+        block_representation += f"| {colorize('prev. hash', 'bold')}: \t {str(self.previous_hash)} \n"
+        block_representation += f"{str(self.data)}\n"
+        block_representation += f"| {'=' * 80}\n"
 
-        return block_rep
+        return block_representation
 
 
     def __bytes__(self) -> bytes:

src/blockchain/blockchain.py

@@ -2,21 +2,25 @@
 import time
 import pickle
 import logging
+import hashlib
 import jsonpickle
 
-from src.utils.constants import *
 from src.blockchain.data import Data
 from src.blockchain.block import Block
 from src.utils.errors import ChainNotFoundError
 from src.utils.utils import encode_file_path_properly
+from src.utils.constants import GENESIS_BLOCK_PREV_HASH, GENESIS_BLOCK_PROOF, GENESIS_BLOCK_DATA, GENESIS_BLOCK_INDEX
 
 
 logger = logging.getLogger(__name__)
 
 
 class Blockchain(object):
 
-    def __init__(self, path_to_chain: str, json_format: bool) -> None:
+    genesis_block = Block(index=GENESIS_BLOCK_INDEX, data=Data(GENESIS_BLOCK_DATA), proof=GENESIS_BLOCK_PROOF, previous_hash=GENESIS_BLOCK_PREV_HASH)
+    genesis_block_hash = hashlib.sha256(bytes(genesis_block)).hexdigest()
+
+    def __init__(self, path_to_chain: str, json_format: bool, force_new_chain: bool) -> None:
         """
 
         Constructor for new ``Blockchain`` object.
@@ -35,7 +39,7 @@ def __init__(self, path_to_chain: str, json_format: bool) -> None:
         self._json_format = json_format
 
         # if local chain exists, load it
-        if os.path.isfile(self.path_to_chain):
+        if os.path.isfile(self.path_to_chain) and not force_new_chain:
 
             logger.debug(f"Load existing chain from disc ...")
             self.load_chain()
@@ -45,7 +49,8 @@ def __init__(self, path_to_chain: str, json_format: bool) -> None:
             logger.debug(f"Create new chain ...")
 
             # if no local chain exists, create the genesis block
-            self.chain = [GENESIS_BLOCK]
+
+            self.chain = [self.genesis_block]
             logger.debug(f"New chain created.")
 
         logger.info("Created 'Blockchain' object.")

src/blockchain/data.py

@@ -2,6 +2,9 @@
 
 from uuid import uuid4
 
+from src.utils.utils import colorize
+
+
 logger = logging.getLogger(__name__)
 
 
@@ -45,11 +48,12 @@ def __hash__(self):
 
     def __repr__(self) -> str:
 
-        data_rep = "Data object with - \n"
-        data_rep += "\t\t\t\tid:\t" + str(self.id) + "\n"
-        data_rep += "\t\t\t\tmessage:" + str(self.message)
+        data_representation =  f"| \t\t{'_' * 66}\n"
+        data_representation += f"| {colorize('data', 'bold')}:\t\t| id: \t{self.id}\n"
+        data_representation += f"| \t\t| message: {self.message}\n"
+        data_representation += f"| \t\t{'_' * 65}"
 
-        return data_rep
+        return data_representation
 
 
     def __eq__(self, other) -> bool:

src/cli/cli.py

@@ -1,3 +1,4 @@
+import time
 import click
 import signal
 import logging
@@ -55,7 +56,8 @@ def get():
 @click.option("--chain_serialization", default="json", type=click.types.Choice(["json", "pickle"]), help=CHAIN_SERIALIZATION_HELP)
 @click.option("--difficulty", default=DEFAULT_DIFFICULTY, type=int, help=DIFFICULTY_HELP)
 @click.option("--neighbours", default=DEFAULT_NEIGHBOURS, type=str, help=NEIGHBOURS_HELP)
-def start(chain_path: str, chain_serialization: str, port: int, difficulty: int, neighbours: str):
+@click.option("--force_new_chain", is_flag=True, type=bool, help=NEIGHBOURS_HELP)
+def start(chain_path: str, chain_serialization: str, port: int, difficulty: int, neighbours: str, force_new_chain: bool):
     """
     Starts a local miner.
     """
@@ -75,7 +77,10 @@ def start(chain_path: str, chain_serialization: str, port: int, difficulty: int,
         neighbours = neighbours.split(",")
 
 
-    miner = Miner(path_to_chain=chain_path, json_format=json_format, port=port, difficulty=difficulty, neighbours=neighbours)
+    logger.debug(f"======================================== STARTED AT {time.strftime('%d.%m.%Y %H:%M:%S', time.localtime())} ========================================\n\n\n")
+
+
+    miner = Miner(path_to_chain=chain_path, json_format=json_format, port=port, difficulty=difficulty, neighbours=neighbours, force_new_chain=force_new_chain)
 
     try:
         signal.signal(signal.SIGTERM, signal_handler)
@@ -89,7 +94,8 @@ def start(chain_path: str, chain_serialization: str, port: int, difficulty: int,
 
         miner.stop_mining()
 
-        logger.debug("======================================== FINISHED ========================================\n\n\n")
+
+        logger.debug(f"======================================== FINISHED AT {time.strftime('%d.%m.%Y %H:%M:%S', time.localtime())} ========================================\n\n\n")
 
 
 @cli.command()
@@ -126,7 +132,7 @@ def chain(host, port):
     if response.status_code == HTTP_OK:
 
         json = response.json()
-        length = json['length']
+        length = json["length"]
         chain = jsonpickle.decode(json["chain"])
 
         click.echo(click.style(f"\nChain with length: {length}\n", fg="green"))
@@ -149,7 +155,7 @@ def neighbours(host, port):
     if response.status_code == HTTP_OK:
 
         json = response.json()
-        length = json['length']
+        length = json["length"]
         neighbours = jsonpickle.decode(json["neighbours"])
 
         click.echo(click.style(f"\nActual are {length} neighbours available.\n", fg="green"))

src/client/miner.py

@@ -22,7 +22,7 @@
 
 class Miner(object):
 
-    def __init__(self, path_to_chain: str, json_format: bool, port: int, difficulty: int, neighbours: list = []) -> None:
+    def __init__(self, path_to_chain: str, json_format: bool, port: int, difficulty: int, neighbours: list, force_new_chain: bool) -> None:
         """
 
         Constructor for new ``Miner`` object.
@@ -33,6 +33,7 @@ def __init__(self, path_to_chain: str, json_format: bool, port: int, difficulty:
             port (int): Port of neighbour.
             difficulty (int): Amount of trailing 0s for proof of work
             neighbours (list): List of known neighbours, e.g. ``["localhost:23456", "miner0815:6666"]``
+            force_new_chain (bool): Force miner to create a new chain instead of use the existing one.
         """
 
         logger.info("Create 'Miner' object ...")
@@ -89,7 +90,7 @@ def __init__(self, path_to_chain: str, json_format: bool, port: int, difficulty:
         self._server_process = None
         self._difficulty = difficulty
         self._not_processed_messages = set()
-        self._blockchain = Blockchain(path_to_chain=encode_file_path_properly(path_to_chain), json_format=json_format)
+        self._blockchain = Blockchain(path_to_chain=encode_file_path_properly(path_to_chain), json_format=json_format, force_new_chain= force_new_chain)
 
         logger.debug(f"Check chain ...")
 

src/utils/constants.py

@@ -1,12 +1,8 @@
-import hashlib
 
-from src.blockchain.data import Data
-from src.blockchain.block import Block
-
-
-GENESIS_DATA = Data("This is the workload of the very first Block in this chain!")
-GENESIS_BLOCK = Block(index=0, data=GENESIS_DATA, proof=None, previous_hash=None)
-GENESIS_BLOCK_HASH = hashlib.sha256(bytes(GENESIS_BLOCK)).hexdigest()
+GENESIS_BLOCK_INDEX = 0
+GENESIS_BLOCK_PROOF = None
+GENESIS_BLOCK_PREV_HASH = None
+GENESIS_BLOCK_DATA = "This is the workload of the very first Block in this chain!"
 
 MAX_NEIGHBOURS = 3
 
@@ -19,15 +15,15 @@
 HTTP_BAD = 400
 HTTP_NOT_FOUND = 404
 
+ADD_ENDPOINT = "/add"
 DATA_ENDPOINT = "/data"
 CHAIN_ENDPOINT = "/chain"
 NEIGHBOURS_ENDPOINT = "/neighbours"
-ADD_ENDPOINT = "/add"
 
 ADD_KEY = "add"
+SEND_DATA_KEY = "data"
 SEND_CHAIN_KEY = "chain"
 SEND_NEIGHBOURS_KEY = "neighbours"
-SEND_DATA_KEY = "data"
 
 MESSAGE_PARAM = "message"
 
@@ -36,15 +32,20 @@
 BACKUP_LOCAL_CHAIN_TIME_SECONDS = 30
 UNPROCESSED_DATA_SYNC_TIME_SECONDS = 5
 
-MINER_LOG_SIZE = 1 * 1024 * 1024 # 2 MB
 MINER_LOG_FILE = "miner.log"
+MINER_LOG_SIZE = 1 * 1024 * 1024 # 2 MB
 LOGGING_FORMAT = "[%(asctime)s - %(filename)-17s:%(lineno)-4s - %(levelname)-7s - %(funcName)-25s]: %(message)s"
 
+COLOR_END = "\033[0m"
+COLOR_RED = "\033[91m"
+COLOR_BOLD = "\033[1m"
+COLOR_GREEN = "\033[92m"
+
 
 ############## CLI Help messages ##############
 
 PORT_HELP                   = "Port of miner."
 HOST_HELP                   = "IPv4 Address of miner."
-CHAIN_SERIALIZATION_HELP    = "Defines the serialization format of chain file. One of these: ['json', 'pickle']"
 DIFFICULTY_HELP             = "Difficulty of the chain"
-NEIGHBOURS_HELP             = "Comma separated 'host:port' list, e.g.: localhost:23456,localhost:34567"
+NEIGHBOURS_HELP             = "Comma separated 'host:port' list, e.g.: localhost:23456,localhost:34567"
+CHAIN_SERIALIZATION_HELP    = "Defines the serialization format of chain file. One of these: ['json', 'pickle']"

src/utils/utils.py

@@ -5,8 +5,8 @@
 from datetime import timedelta
 from urllib.parse import urlparse
 
-from src.utils.constants import DEFAULT_PORT
 from src.utils.errors import ProgramKilledError, PortValueError
+from src.utils.constants import DEFAULT_PORT, COLOR_BOLD, COLOR_END, COLOR_GREEN, COLOR_RED
 
 
 logger = logging.getLogger(__name__)
@@ -109,6 +109,22 @@ def create_proper_url_string(host_port: (str, int), path: str) -> str:
     return f"http://{host_port[0]}:{host_port[1]}/{path}"
 
 
+def colorize(text: str, color: str) -> str:
+
+    if color == "bold":
+        return f"{COLOR_BOLD}{text}{COLOR_END}"
+
+    elif color == "green":
+        return f"{COLOR_GREEN}{text}{COLOR_END}"
+
+    elif color == "red":
+        return f"{COLOR_RED}{text}{COLOR_END}"
+
+    else:
+        logger.warning(f"Could not find handle for type: '{color}'")
+        return text
+
+
 def signal_handler(signum, frame):
     """
 

tests/test_block.py

@@ -2,13 +2,13 @@
 
 from src.blockchain.data import Data
 from src.blockchain.block import Block
-from src.utils.constants import GENESIS_BLOCK
+from src.blockchain.blockchain import Blockchain
 
 
 data = Data("dummy data")
 same_data = Data("dummy data")
 dummy_prev_hash = "e59be601c9213694f0b72534148199b24d1ed7c1c29c02ba4602e780015a7663"
-another_genesis_block = Block(index=0, data=GENESIS_BLOCK.data, proof=None, previous_hash=None)
+another_genesis_block = Block(index=0, data=Blockchain.genesis_block.data, proof=None, previous_hash=None)
 
 
 def test_constructor():
@@ -68,16 +68,16 @@ def test_timestamp():
 
 def test_equality():
 
-    assert GENESIS_BLOCK == GENESIS_BLOCK
+    assert Blockchain.genesis_block == Blockchain.genesis_block
     assert another_genesis_block == another_genesis_block
-    assert GENESIS_BLOCK != another_genesis_block
+    assert Blockchain.genesis_block != another_genesis_block
 
 
 def test_negative_equality():
 
-    assert GENESIS_BLOCK != another_genesis_block
+    assert Blockchain.genesis_block != another_genesis_block
 
     string_object = "This is a random String object"
 
-    assert GENESIS_BLOCK != string_object
+    assert Blockchain.genesis_block != string_object
     assert string_object != another_genesis_block

tests/test_blockchain.py

@@ -3,12 +3,11 @@
 import pytest
 
 from src.blockchain.data import Data
-from src.utils.constants import GENESIS_BLOCK
+from src.blockchain.block import Block
 from src.blockchain.blockchain import Blockchain
 from src.utils.utils import encode_file_path_properly
 
 
-
 constructor_json_format = [True, False]
 
 path_to_chain = "test_chain/test.chain"
@@ -28,21 +27,21 @@ def clean_chain_file_fixture():
 def test_constructor(json_format, clean_chain_file_fixture):
 
     # test without local chain
-    blockchain_without_local_chain = Blockchain(path_to_chain=path_to_chain, json_format=json_format)
+    blockchain_without_local_chain = Blockchain(path_to_chain=path_to_chain, json_format=json_format, force_new_chain=False)
     assert isinstance(blockchain_without_local_chain, Blockchain)
-    assert blockchain_without_local_chain.chain[0] == GENESIS_BLOCK
-    assert blockchain_without_local_chain.last_block == GENESIS_BLOCK
+    assert blockchain_without_local_chain.chain[0] == Blockchain.genesis_block
+    assert blockchain_without_local_chain.last_block == Blockchain.genesis_block
 
     # test with local chain
-    blockchain_with_local_chain = Blockchain(path_to_chain=path_to_chain, json_format=json_format)
+    blockchain_with_local_chain = Blockchain(path_to_chain=path_to_chain, json_format=json_format, force_new_chain=False)
     assert isinstance(blockchain_with_local_chain, Blockchain)
-    assert blockchain_with_local_chain.chain[0] == GENESIS_BLOCK
-    assert blockchain_with_local_chain.last_block == GENESIS_BLOCK
+    assert blockchain_with_local_chain.chain[0] == Blockchain.genesis_block
+    assert blockchain_with_local_chain.last_block == Blockchain.genesis_block
 
 
 @pytest.mark.parametrize("json_format", constructor_json_format)
 def test_add_new_block(json_format, clean_chain_file_fixture):
-    blockchain = Blockchain(path_to_chain=path_to_chain, json_format=json_format)
+    blockchain = Blockchain(path_to_chain=path_to_chain, json_format=json_format, force_new_chain=False)
 
     blockchain.add_new_block(data=Data("second block"), proof=4711, previous_hash="e59be601c9213694f0b72534148199b24d1ed7c1c29c02ba4602e780015a7663")
     blockchain.add_new_block(data=Data("third block"), proof=42, previous_hash="637ae601c9213694f0b72534148199b24d1ed7c1c29c02ba4602e780015a09ab")
@@ -51,7 +50,7 @@ def test_add_new_block(json_format, clean_chain_file_fixture):
     block_1 = blockchain.chain[1]
     block_2 = blockchain.chain[2]
 
-    assert block_0 == GENESIS_BLOCK
+    assert block_0 == Blockchain.genesis_block
     assert block_2 == blockchain.last_block
 
     assert block_0 != block_1
@@ -63,10 +62,10 @@ def test_add_new_block(json_format, clean_chain_file_fixture):
 @pytest.mark.parametrize("json_format", constructor_json_format)
 def test_chain_method(json_format, clean_chain_file_fixture):
 
-    blockchain = Blockchain(path_to_chain=path_to_chain, json_format=json_format)
+    blockchain = Blockchain(path_to_chain=path_to_chain, json_format=json_format, force_new_chain=False)
     chain = blockchain.chain
     genesis_block = chain[0]
 
-    assert genesis_block == GENESIS_BLOCK
+    assert genesis_block == genesis_block
 
 # TODO: Tests for private fuctions..