From dba91a9a6783057d7f308eeabb0ef4a6772c9562 Mon Sep 17 00:00:00 2001 From: Gavin Andresen Date: Fri, 4 Jan 2013 20:05:56 -0500 Subject: [PATCH] spendfrom.py sends coins from a particular address or addresses Should be both useful and also a pretty good demonstration of using the raw transactions API. --- contrib/spendfrom/README | 32 ++++ contrib/spendfrom/setup.py | 9 ++ contrib/spendfrom/spendfrom.py | 267 +++++++++++++++++++++++++++++++++ 3 files changed, 308 insertions(+) create mode 100644 contrib/spendfrom/README create mode 100644 contrib/spendfrom/setup.py create mode 100755 contrib/spendfrom/spendfrom.py diff --git a/contrib/spendfrom/README b/contrib/spendfrom/README new file mode 100644 index 00000000..8a087a0c --- /dev/null +++ b/contrib/spendfrom/README @@ -0,0 +1,32 @@ +Use the raw transactions API to send coins received on a particular +address (or addresses). + +Depends on jsonrpc + +Usage: + +spendfrom.py --from=FROMADDRESS1[,FROMADDRESS2] --to=TOADDRESS --amount=amount \ + --fee=fee --datadir=/path/to/.bitcoin --testnet --dry_run + +With no arguments, outputs a list of amounts associated with addresses. + +With arguments, sends coins received by the FROMADDRESS addresses to the TOADDRESS. + +You may explictly specify how much fee to pay (a fee more than 1% of the amount +will fail, though, to prevent bitcoin-losing accidents). Spendfrom may fail if +it thinks the transaction would never be confirmed (if the amount being sent is +too small, or if the transaction is too many bytes for the fee). + +If a change output needs to be created, the change will be sent to the last +FROMADDRESS (if you specify just one FROMADDRESS, change will go back to it). + +If --datadir is not specified, the default datadir is used. + +The --dry_run option will just create and sign the the transaction and print +the transaction data (as hexadecimal), instead of broadcasting it. + +If the transaction is created and broadcast successfully, a transaction id +is printed. + +If this was a tool for end-users and not programmers, it would have much friendlier +error-handling. diff --git a/contrib/spendfrom/setup.py b/contrib/spendfrom/setup.py new file mode 100644 index 00000000..01b9768a --- /dev/null +++ b/contrib/spendfrom/setup.py @@ -0,0 +1,9 @@ +from distutils.core import setup +setup(name='btcspendfrom', + version='1.0', + description='Command-line utility for bitcoin "coin control"', + author='Gavin Andresen', + author_email='gavin@bitcoinfoundation.org', + requires=['jsonrpc'], + scripts=['spendfrom.py'], + ) diff --git a/contrib/spendfrom/spendfrom.py b/contrib/spendfrom/spendfrom.py new file mode 100755 index 00000000..72ee0425 --- /dev/null +++ b/contrib/spendfrom/spendfrom.py @@ -0,0 +1,267 @@ +#!/usr/bin/env python +# +# Use the raw transactions API to spend bitcoins received on particular addresses, +# and send any change back to that same address. +# +# Example usage: +# spendfrom.py # Lists available funds +# spendfrom.py --from=ADDRESS --to=ADDRESS --amount=11.00 +# +# Assumes it will talk to a bitcoind or Bitcoin-Qt running +# on localhost. +# +# Depends on jsonrpc +# + +from decimal import * +import getpass +import math +import os +import os.path +import platform +import sys +import time +from jsonrpc import ServiceProxy, json + +BASE_FEE=Decimal("0.001") + +def check_json_precision(): + """Make sure json library being used does not lose precision converting BTC values""" + n = Decimal("20000000.00000003") + satoshis = int(json.loads(json.dumps(float(n)))*1.0e8) + if satoshis != 2000000000000003: + raise RuntimeError("JSON encode/decode loses precision") + +def determine_db_dir(): + """Return the default location of the bitcoin data directory""" + if platform.system() == "Darwin": + return os.path.expanduser("~/Library/Application Support/Bitcoin/") + elif platform.system() == "Windows": + return os.path.join(os.environ['APPDATA'], "Bitcoin") + return os.path.expanduser("~/.bitcoin") + +def read_bitcoin_config(dbdir): + """Read the bitcoin.conf file from dbdir, returns dictionary of settings""" + from ConfigParser import SafeConfigParser + + class FakeSecHead(object): + def __init__(self, fp): + self.fp = fp + self.sechead = '[all]\n' + def readline(self): + if self.sechead: + try: return self.sechead + finally: self.sechead = None + else: + s = self.fp.readline() + if s.find('#') != -1: + s = s[0:s.find('#')].strip() +"\n" + return s + + config_parser = SafeConfigParser() + config_parser.readfp(FakeSecHead(open(os.path.join(dbdir, "bitcoin.conf")))) + return dict(config_parser.items("all")) + +def connect_JSON(config): + """Connect to a bitcoin JSON-RPC server""" + testnet = config.get('testnet', '0') + testnet = (int(testnet) > 0) # 0/1 in config file, convert to True/False + if not 'rpcport' in config: + config['rpcport'] = 18332 if testnet else 8332 + connect = "http://%s:%s@127.0.0.1:%s"%(config['rpcuser'], config['rpcpassword'], config['rpcport']) + try: + result = ServiceProxy(connect) + # ServiceProxy is lazy-connect, so send an RPC command mostly to catch connection errors, + # but also make sure the bitcoind we're talking to is/isn't testnet: + if result.getmininginfo()['testnet'] != testnet: + sys.stderr.write("RPC server at "+connect+" testnet setting mismatch\n") + sys.exit(1) + return result + except: + sys.stderr.write("Error connecting to RPC server at "+connect+"\n") + sys.exit(1) + +def unlock_wallet(bitcoind): + info = bitcoind.getinfo() + if 'unlocked_until' not in info: + return True # wallet is not encrypted + t = int(info['unlocked_until']) + if t <= time.time(): + try: + passphrase = getpass.getpass("Wallet is locked; enter passphrase: ") + bitcoind.walletpassphrase(passphrase, 5) + except: + sys.stderr.write("Wrong passphrase\n") + + info = bitcoind.getinfo() + return int(info['unlocked_until']) > time.time() + +def list_available(bitcoind): + address_summary = dict() + + address_to_account = dict() + for info in bitcoind.listreceivedbyaddress(0): + address_to_account[info["address"]] = info["account"] + + unspent = bitcoind.listunspent(0) + for output in unspent: + # listunspent doesn't give addresses, so: + rawtx = bitcoind.getrawtransaction(output['txid'], 1) + vout = rawtx["vout"][output['vout']] + pk = vout["scriptPubKey"] + + # This code only deals with ordinary pay-to-bitcoin-address + # or pay-to-script-hash outputs right now; anything exotic is ignored. + if pk["type"] != "pubkeyhash" and pk["type"] != "scripthash": + continue + + address = pk["addresses"][0] + if address in address_summary: + address_summary[address]["total"] += vout["value"] + address_summary[address]["outputs"].append(output) + else: + address_summary[address] = { + "total" : vout["value"], + "outputs" : [output], + "account" : address_to_account.get(address, "") + } + + return address_summary + +def select_coins(needed, inputs): + # Feel free to improve this, this is good enough for my simple needs: + outputs = [] + have = Decimal("0.0") + n = 0 + while have < needed and n < len(inputs): + outputs.append({ "txid":inputs[n]["txid"], "vout":inputs[n]["vout"]}) + have += inputs[n]["amount"] + n += 1 + return (outputs, have-needed) + +def create_tx(bitcoind, fromaddresses, toaddress, amount, fee): + all_coins = list_available(bitcoind) + + total_available = Decimal("0.0") + needed = amount+fee + potential_inputs = [] + for addr in fromaddresses: + if addr not in all_coins: + continue + potential_inputs.extend(all_coins[addr]["outputs"]) + total_available += all_coins[addr]["total"] + + if total_available < needed: + sys.stderr.write("Error, only %f BTC available, need %f\n"%(total_available, needed)); + sys.exit(1) + + # + # Note: + # Python's json/jsonrpc modules have inconsistent support for Decimal numbers. + # Instead of wrestling with getting json.dumps() (used by jsonrpc) to encode + # Decimals, I'm casting amounts to float before sending them to bitcoind. + # + outputs = { toaddress : float(amount) } + (inputs, change_amount) = select_coins(needed, potential_inputs) + if change_amount > BASE_FEE: # don't bother with zero or tiny change + change_address = fromaddresses[-1] + if change_address in outputs: + outputs[change_address] += float(change_amount) + else: + outputs[change_address] = float(change_amount) + + rawtx = bitcoind.createrawtransaction(inputs, outputs) + signed_rawtx = bitcoind.signrawtransaction(rawtx) + if not signed_rawtx["complete"]: + sys.stderr.write("signrawtransaction failed\n") + sys.exit(1) + txdata = signed_rawtx["hex"] + + return txdata + +def compute_amount_in(bitcoind, txinfo): + result = Decimal("0.0") + for vin in txinfo['vin']: + in_info = bitcoind.getrawtransaction(vin['txid'], 1) + vout = in_info['vout'][vin['vout']] + result = result + vout['value'] + return result + +def compute_amount_out(txinfo): + result = Decimal("0.0") + for vout in txinfo['vout']: + result = result + vout['value'] + return result + +def sanity_test_fee(bitcoind, txdata_hex, max_fee): + class FeeError(RuntimeError): + pass + try: + txinfo = bitcoind.decoderawtransaction(txdata_hex) + total_in = compute_amount_in(bitcoind, txinfo) + total_out = compute_amount_out(txinfo) + if total_in-total_out > max_fee: + raise FeeError("Rejecting transaction, unreasonable fee of "+str(total_in-total_out)) + + tx_size = len(txdata_hex)/2 + kb = tx_size/1000 # integer division rounds down + if kb > 1 and fee < BASE_FEE: + raise FeeError("Rejecting no-fee transaction, larger than 1000 bytes") + if total_in < 0.01 and fee < BASE_FEE: + raise FeeError("Rejecting no-fee, tiny-amount transaction") + # Exercise for the reader: compute transaction priority, and + # warn if this is a very-low-priority transaction + + except FeeError as err: + sys.stderr.write((str(err)+"\n")) + sys.exit(1) + +def main(): + import optparse + + parser = optparse.OptionParser(usage="%prog [options]") + parser.add_option("--from", dest="fromaddresses", default=None, + help="addresses to get bitcoins from") + parser.add_option("--to", dest="to", default=None, + help="address to get send bitcoins to") + parser.add_option("--amount", dest="amount", default=None, + help="amount to send") + parser.add_option("--fee", dest="fee", default="0.0", + help="fee to include") + parser.add_option("--datadir", dest="datadir", default=determine_db_dir(), + help="location of bitcoin.conf file with RPC username/password (default: %default)") + parser.add_option("--testnet", dest="testnet", default=False, action="store_true", + help="Use the test network") + parser.add_option("--dry_run", dest="dry_run", default=False, action="store_true", + help="Don't broadcast the transaction, just create and print the transaction data") + + (options, args) = parser.parse_args() + + check_json_precision() + config = read_bitcoin_config(options.datadir) + if options.testnet: config['testnet'] = True + bitcoind = connect_JSON(config) + + if options.amount is None: + address_summary = list_available(bitcoind) + for address,info in address_summary.iteritems(): + n_transactions = len(info['outputs']) + if n_transactions > 1: + print("%s %.8f %s (%d transactions)"%(address, info['total'], info['account'], n_transactions)) + else: + print("%s %.8f %s"%(address, info['total'], info['account'])) + else: + fee = Decimal(options.fee) + amount = Decimal(options.amount) + while unlock_wallet(bitcoind) == False: + pass # Keep asking for passphrase until they get it right + txdata = create_tx(bitcoind, options.fromaddresses.split(","), options.to, amount, fee) + sanity_test_fee(bitcoind, txdata, amount*Decimal("0.01")) + if options.dry_run: + print(txdata) + else: + txid = bitcoind.sendrawtransaction(txdata) + print(txid) + +if __name__ == '__main__': + main()