generate-scenario-from-core.py

#! /usr/bin/env python3

import argparse
import json
from decimal import Decimal, ROUND_DOWN
from random import randrange

COIN = 100000000
SATOSHI = Decimal(0.00000001)
KILO = 1000

def satoshi_round(amount):
    return Decimal(amount).quantize(Decimal('0.00000001'), rounding=ROUND_DOWN)

def to_sat(amount):
    return int(amount * COIN)

def to_coin(amount):
    return satoshi_round(amount / COIN)

parser = argparse.ArgumentParser(description="Generates a simulation scenario from a Bitcoin Core wallet. Requires Bitcoin Core 0.19.0 or later.")
parser.add_argument("inputfile", help="File to read transactions")
parser.add_argument("outputfile", help="File to output to")

args = parser.parse_args()

# Fetch all of the transactions in the wallet
inputfile = open(args.inputfile)

txs = json.load(inputfile)

with open(args.outputfile, "w") as f:
    for tx in txs:
        # Bitcoin Core gives us the amount as positive for receiving, and negative for sending
        amount = abs(to_sat(tx["amount"]))
        # To protect user privacy, fuzzify by adding or subtracting a random percentage up to 5%
        lower = int(amount * 0.95)
        upper = int(amount * 1.05)
        amount = to_coin(randrange(lower, upper, 1))

        # Get feerate
        if tx["category"] == "send":
            amount = -amount
        # Use a feerate of 1 sat/vb for deposits
        feerate = satoshi_round(SATOSHI * KILO)

        f.write(f"{amount:.8f},{feerate:.8f}\n")