text: #!/usr/bin/env python3
  # Copyright (c) 2021 The Bitcoin Core developers
  # Distributed under the MIT software license, see the accompanying
  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  """Test a basic M-of-N multisig setup between multiple people using descriptor wallets and PSBTs, as well as a signing flow.
  
  This is meant to be documentation as much as functional tests, so it is kept as simple and readable as possible.
  """
  
  from test_framework.address import base58_to_byte
  from test_framework.test_framework import BitcoinTestFramework
  from test_framework.util import (
      assert_approx,
      assert_equal,
  )
  
  
  class WalletMultisigDescriptorPSBTTest(BitcoinTestFramework):
      def set_test_params(self):
          self.num_nodes = 3
          self.setup_clean_chain = True
          self.wallet_names = []
          self.extra_args = [["-keypool=100", "-addresstype=bech32"]] * self.num_nodes
  
      def skip_test_if_missing_module(self):
          self.skip_if_no_wallet()
          self.skip_if_no_sqlite()
  
      @staticmethod
      def _get_xpub(wallet):
          """Extract the wallet's xpubs using `listdescriptors` and pick the one from the `pkh` descriptor since it's least likely to be accidentally reused (legacy addresses)."""
          descriptor = next(filter(lambda d: d["desc"].startswith("pkh"), wallet.listdescriptors()["descriptors"]))
          return descriptor["desc"].split("]")[-1].split("/")[0]
  
      @staticmethod
      def _check_psbt(psbt, to, value, multisig):
          """Helper function for any of the N participants to check the psbt with decodepsbt and verify it is OK before signing."""
          tx = multisig.decodepsbt(psbt)["tx"]
          amount = 0
          for vout in tx["vout"]:
              address = vout["scriptPubKey"]["address"]
              assert_equal(multisig.getaddressinfo(address)["ischange"], address != to)
              if address == to:
                  amount += vout["value"]
          assert_approx(amount, float(value), vspan=0.001)
  
      def participants_create_multisigs(self, xpubs):
          """The multisig is created by importing the following descriptors. The resulting wallet is watch-only and every participant can do this."""
          # some simple validation
          assert_equal(len(xpubs), self.N)
          # a sanity-check/assertion, this will throw if the base58 checksum of any of the provided xpubs are invalid
          for xpub in xpubs:
              base58_to_byte(xpub)
  
          for i, node in enumerate(self.nodes):
              node.createwallet(wallet_name=f"{self.name}_{i}", blank=True, descriptors=True, disable_private_keys=True)
              multisig = node.get_wallet_rpc(f"{self.name}_{i}")
              external = multisig.getdescriptorinfo(f"wsh(sortedmulti({self.M},{f'/0/*,'.join(xpubs)}/0/*))")
              internal = multisig.getdescriptorinfo(f"wsh(sortedmulti({self.M},{f'/1/*,'.join(xpubs)}/1/*))")
              result = multisig.importdescriptors([
                  {  # receiving addresses (internal: False)
                      "desc": external["descriptor"],
                      "active": True,
                      "internal": False,
                      "timestamp": "now",
                  },
                  {  # change addresses (internal: True)
                      "desc": internal["descriptor"],
                      "active": True,
                      "internal": True,
                      "timestamp": "now",
                  },
              ])
              assert all(r["success"] for r in result)
              yield multisig
  
      def run_test(self):
          self.M = 2
          self.N = self.num_nodes
          self.name = f"{self.M}_of_{self.N}_multisig"
          self.log.info(f"Testing {self.name}...")
  
          participants = {
              # Every participant generates an xpub. The most straightforward way is to create a new descriptor wallet.
              # This wallet will be the participant's `signer` for the resulting multisig. Avoid reusing this wallet for any other purpose (for privacy reasons).
              "signers": [node.get_wallet_rpc(node.createwallet(wallet_name=f"participant_{self.nodes.index(node)}", descriptors=True)["name"]) for node in self.nodes],
              # After participants generate and exchange their xpubs they will each create their own watch-only multisig.
              # Note: these multisigs are all the same, this just highlights that each participant can independently verify everything on their own node.
              "multisigs": []
          }
  
          self.log.info("Generate and exchange xpubs...")
          xpubs = [self._get_xpub(signer) for signer in participants["signers"]]
  
          self.log.info("Every participant imports the following descriptors to create the watch-only multisig...")
          participants["multisigs"] = list(self.participants_create_multisigs(xpubs))
  
          self.log.info("Check that every participant's multisig generates the same addresses...")
          for _ in range(10):  # we check that the first 10 generated addresses are the same for all participant's multisigs
              receive_addresses = [multisig.getnewaddress() for multisig in participants["multisigs"]]
              all(address == receive_addresses[0] for address in receive_addresses)
              change_addresses = [multisig.getrawchangeaddress() for multisig in participants["multisigs"]]
              all(address == change_addresses[0] for address in change_addresses)
  
          self.log.info("Get a mature utxo to send to the multisig...")
          coordinator_wallet = participants["signers"][0]
          self.generatetoaddress(self.nodes[0], 101, coordinator_wallet.getnewaddress())
  
          deposit_amount = 6.15
          multisig_receiving_address = participants["multisigs"][0].getnewaddress()
          self.log.info("Send funds to the resulting multisig receiving address...")
          coordinator_wallet.sendtoaddress(multisig_receiving_address, deposit_amount)
          self.generate(self.nodes[0], 1)
          for participant in participants["multisigs"]:
              assert_approx(participant.getbalance(), deposit_amount, vspan=0.001)
  
          self.log.info("Send a transaction from the multisig!")
          to = participants["signers"][self.N - 1].getnewaddress()
          value = 1
          self.log.info("First, make a sending transaction, created using `walletcreatefundedpsbt` (anyone can initiate this)...")
          psbt = participants["multisigs"][0].walletcreatefundedpsbt(inputs=[], outputs={to: value}, options={"feeRate": 0.00010})
  
          psbts = []
          self.log.info("Now at least M users check the psbt with decodepsbt and (if OK) signs it with walletprocesspsbt...")
          for m in range(self.M):
              signers_multisig = participants["multisigs"][m]
              self._check_psbt(psbt["psbt"], to, value, signers_multisig)
              signing_wallet = participants["signers"][m]
              partially_signed_psbt = signing_wallet.walletprocesspsbt(psbt["psbt"])
              psbts.append(partially_signed_psbt["psbt"])
  
          self.log.info("Finally, collect the signed PSBTs with combinepsbt, finalizepsbt, then broadcast the resulting transaction...")
          combined = coordinator_wallet.combinepsbt(psbts)
          finalized = coordinator_wallet.finalizepsbt(combined)
          coordinator_wallet.sendrawtransaction(finalized["hex"])
  
          self.log.info("Check that balances are correct after the transaction has been included in a block.")
          self.generate(self.nodes[0], 1)
          assert_approx(participants["multisigs"][0].getbalance(), deposit_amount - value, vspan=0.001)
          assert_equal(participants["signers"][self.N - 1].getbalance(), value)
  
          self.log.info("Send another transaction from the multisig, this time with a daisy chained signing flow (one after another in series)!")
          psbt = participants["multisigs"][0].walletcreatefundedpsbt(inputs=[], outputs={to: value}, options={"feeRate": 0.00010})
          for m in range(self.M):
              signers_multisig = participants["multisigs"][m]
              self._check_psbt(psbt["psbt"], to, value, signers_multisig)
              signing_wallet = participants["signers"][m]
              psbt = signing_wallet.walletprocesspsbt(psbt["psbt"])
              assert_equal(psbt["complete"], m == self.M - 1)
          finalized = coordinator_wallet.finalizepsbt(psbt["psbt"])
          coordinator_wallet.sendrawtransaction(finalized["hex"])
  
          self.log.info("Check that balances are correct after the transaction has been included in a block.")
          self.generate(self.nodes[0], 1)
          assert_approx(participants["multisigs"][0].getbalance(), deposit_amount - (value * 2), vspan=0.001)
          assert_equal(participants["signers"][self.N - 1].getbalance(), value * 2)
  
  
  if __name__ == "__main__":
      WalletMultisigDescriptorPSBTTest().main()
  