bscli.py

# -*- coding: utf-8 -*-
# ===================================================
# ==================== META DATA ===================
# ==================================================
__author__ = "Daxeel Soni"
__url__ = "https://daxeel.github.io"
__email__ = "daxeelsoni44@gmail.com"
__license__ = "MIT"
__version__ = "0.1"
__maintainer__ = "Daxeel Soni"

# ==================================================
# ================= IMPORT MODULES =================
# ==================================================
import click
import urllib
import json
import sys

from blockchain.chain import Block, Blockchain

# ==================================================
# ===== SUPPORTED COMMANDS LIST IN BLOCKSHELL ======
# ==================================================
SUPPORTED_COMMANDS = [
    'sendtx',
    'mineblock',
    'allblocks',
    'mempool',
    'getblock',
    'help'
]

# Init blockchain
coin = Blockchain()

# Create group of commands
@click.group()
def cli():
    """
        Create a group of commands for CLI
    """
    pass

# ==================================================
# ============= BLOCKSHELL CLI COMMAND =============
# ==================================================
@cli.command()
@click.option("--difficulty", default=3, help="Define difficulty level of blockchain.")
def init(difficulty):
    """Initialize local blockchain"""
    print("""
  ____    _                  _       _____   _              _   _
 |  _ \  | |                | |     / ____| | |            | | | |
 | |_) | | |   ___     ___  | | __ | (___   | |__     ___  | | | |
 |  _ <  | |  / _ \   / __| | |/ /  \___ \  | '_ \   / _ \ | | | |
 | |_) | | | | (_) | | (__  |   <   ____) | | | | | |  __/ | | | |
 |____/  |_|  \___/   \___| |_|\_\ |_____/  |_| |_|  \___| |_| |_|

 > A command line utility for learning Blockchain concepts.
 > Type 'help' to see supported commands.
 > Project by Daxeel Soni, edits and additional features by Rustie Lin

    """)

    # Set difficulty of blockchain
    coin.difficulty = difficulty

    # Start blockshell shell
    while True:
        if sys.version_info[0] > 2:
            cmd = input("[BlockShell] $ ")
        else:
            cmd = raw_input("[BlockShell] $ ")

        processInput(cmd)

# Process input from Blockshell shell
def processInput(cmd):
    """
        Method to process user input from Blockshell CLI.
    """
    userCmd = cmd.split()[0]
    if len(cmd) > 0:
        if userCmd in SUPPORTED_COMMANDS:
            globals()[userCmd](cmd)
        else:
            # error
            msg = "Command not found. Try help command for documentation"
            throwError(msg)


# ==================================================
# =========== BLOCKSHELL COMMAND METHODS ===========
# ==================================================
def sendtx(cmd):
    """
        Send Transaction - Method to perform new transaction on blockchain.
    """
    txData = cmd.split("sendtx ")[-1]
    if "{" in txData:
        txData = json.loads(txData)
    print("Sending transaction...")
    coin.addTx(txData)

def mineblock(cmd):
    """
        Mine a block - Method to mine using PoW and add a block to the blockchain.
    """
    indices = cmd.split()[1:]
    data = []
    try:
        indices = [int(x) for x in indices]
        indices.sort()

        if len(indices) > 0:
            while indices:
                data.append(coin.mempool.pop(indices.pop()))
        else:
            while coin.mempool:
                data.append(coin.mempool.pop())

        coin.addBlock(Block(data))
    except:
        throwError("Invalid block indices")


def allblocks(cmd):
    """
        Method to list all mined blocks.
    """
    print("")
    for eachBlock in coin.chain:
        print(eachBlock.hash)
    print("")

def mempool(cmd):
    """
        Method to list all pending transactions in the mempool.
    """
    print("")
    for i in range(0, len(coin.mempool)):
        print(i, coin.mempool[i])
    print("")

def getblock(cmd):
    """
        Method to fetch the details of block for given hash.
    """
    blockHash = cmd.split(" ")[-1]
    for eachBlock in coin.chain:
        if eachBlock.hash == blockHash:
            print("")
            print(json.dumps(eachBlock.__dict__, indent=4, sort_keys=True))
            print("")

def help(cmd):
    """
        Method to display supported commands in Blockshell
    """
    print("Commands:")
    print("   sendtx <transaction data>          Send new transaction")
    print("   mineblocks [transaction indices]   Adds transactions to a block and mines")
    print("   allblocks                          Fetch all mined blocks in blockchain")
    print("   mempool                            Fetch all pending transactions in the mempool")
    print("   getblock <block hash>              Fetch information about particular block")

def throwError(msg):
    """
        Method to throw an error from Blockshell.
    """
    print("Error : " + msg)