Merge #13932: Additional utility RPCs for PSBT

540729ef4b Implement analyzepsbt RPC and tests (Andrew Chow)
77542cf2a5 Move PSBT UTXO fetching to a separate method (Andrew Chow)
cb40b3abd4 Figure out what is missing during signing (Andrew Chow)
08f749c914 Implement joinpsbts RPC and tests (Andrew Chow)
7344a7b998 Implement utxoupdatepsbt RPC and tests (Andrew Chow)

Pull request description:

  This PR adds 3 new utility RPCs for interacting with PSBTs.

  `utxoupdatepsbt` updates a PSBT with UTXO information from the node. It only works with witness UTXOs because full transactions (as would be needed for non-witness UTXOs) are not available unless txindex is enabled.

  `joinpsbts` joins the inputs from multiple distinct PSBTs into one PSBT. e.g. if PSBT 1 has inputs 1 and 2, and PSBT 2 has inputs 3 and 4, `joinpsbts` would create a new PSBT with inputs 1, 2, 3, and 4.

  `analyzepsbt` analyzes a PSBT and determines the current state of it and all of its inputs, and the next step that needs to be done.

Tree-SHA512: 3c1fa302201abca76a8901d0c2be7b4ccbce334d989533c215f8b3e50e22f2f018ce6209544b26789f58f5980a253c0655111e1e20d47d5656e0414c64891a5c

test/functional/rpc_psbt.py

@@ -5,8 +5,9 @@
 """Test the Partially Signed Transaction RPCs.
 """
 
+from decimal import Decimal
 from test_framework.test_framework import BitcoinTestFramework
-from test_framework.util import assert_equal, assert_raises_rpc_error, find_output, disconnect_nodes, connect_nodes_bi, sync_blocks
+from test_framework.util import assert_equal, assert_raises_rpc_error, connect_nodes_bi, disconnect_nodes, find_output, sync_blocks
 
 import json
 import os
@@ -20,7 +21,7 @@ class PSBTTest(BitcoinTestFramework):
         self.setup_clean_chain = False
         self.num_nodes = 3
        # TODO: remove -txindex. Currently required for getrawtransaction call.
-        self.extra_args = [[], ["-txindex"], ["-txindex"]]
+        self.extra_args = [["-txindex"], ["-txindex"], ["-txindex"]]
 
     def skip_test_if_missing_module(self):
         self.skip_if_no_wallet()
@@ -296,5 +297,72 @@ class PSBTTest(BitcoinTestFramework):
         # Test decoding error: invalid base64
         assert_raises_rpc_error(-22, "TX decode failed invalid base64", self.nodes[0].decodepsbt, ";definitely not base64;")
 
+        # Send to all types of addresses
+        addr1 = self.nodes[1].getnewaddress("", "bech32")
+        txid1 = self.nodes[0].sendtoaddress(addr1, 11)
+        vout1 = find_output(self.nodes[0], txid1, 11)
+        addr2 = self.nodes[1].getnewaddress("", "legacy")
+        txid2 = self.nodes[0].sendtoaddress(addr2, 11)
+        vout2 = find_output(self.nodes[0], txid2, 11)
+        addr3 = self.nodes[1].getnewaddress("", "p2sh-segwit")
+        txid3 = self.nodes[0].sendtoaddress(addr3, 11)
+        vout3 = find_output(self.nodes[0], txid3, 11)
+        self.sync_all()
+
+        # Update a PSBT with UTXOs from the node
+        # Bech32 inputs should be filled with witness UTXO. Other inputs should not be filled because they are non-witness
+        psbt = self.nodes[1].createpsbt([{"txid":txid1, "vout":vout1},{"txid":txid2, "vout":vout2},{"txid":txid3, "vout":vout3}], {self.nodes[0].getnewaddress():32.999})
+        decoded = self.nodes[1].decodepsbt(psbt)
+        assert "witness_utxo" not in decoded['inputs'][0] and "non_witness_utxo" not in decoded['inputs'][0]
+        assert "witness_utxo" not in decoded['inputs'][1] and "non_witness_utxo" not in decoded['inputs'][1]
+        assert "witness_utxo" not in decoded['inputs'][2] and "non_witness_utxo" not in decoded['inputs'][2]
+        updated = self.nodes[1].utxoupdatepsbt(psbt)
+        decoded = self.nodes[1].decodepsbt(updated)
+        assert "witness_utxo" in decoded['inputs'][0] and "non_witness_utxo" not in decoded['inputs'][0]
+        assert "witness_utxo" not in decoded['inputs'][1] and "non_witness_utxo" not in decoded['inputs'][1]
+        assert "witness_utxo" not in decoded['inputs'][2] and "non_witness_utxo" not in decoded['inputs'][2]
+
+        # Two PSBTs with a common input should not be joinable
+        psbt1 = self.nodes[1].createpsbt([{"txid":txid1, "vout":vout1}], {self.nodes[0].getnewaddress():Decimal('10.999')})
+        assert_raises_rpc_error(-8, "exists in multiple PSBTs", self.nodes[1].joinpsbts, [psbt1, updated])
+
+        # Join two distinct PSBTs
+        addr4 = self.nodes[1].getnewaddress("", "p2sh-segwit")
+        txid4 = self.nodes[0].sendtoaddress(addr4, 5)
+        vout4 = find_output(self.nodes[0], txid4, 5)
+        self.nodes[0].generate(6)
+        self.sync_all()
+        psbt2 = self.nodes[1].createpsbt([{"txid":txid4, "vout":vout4}], {self.nodes[0].getnewaddress():Decimal('4.999')})
+        psbt2 = self.nodes[1].walletprocesspsbt(psbt2)['psbt']
+        psbt2_decoded = self.nodes[0].decodepsbt(psbt2)
+        assert "final_scriptwitness" in psbt2_decoded['inputs'][0] and "final_scriptSig" in psbt2_decoded['inputs'][0]
+        joined = self.nodes[0].joinpsbts([psbt, psbt2])
+        joined_decoded = self.nodes[0].decodepsbt(joined)
+        assert len(joined_decoded['inputs']) == 4 and len(joined_decoded['outputs']) == 2 and "final_scriptwitness" not in joined_decoded['inputs'][3] and "final_scriptSig" not in joined_decoded['inputs'][3]
+
+        # Newly created PSBT needs UTXOs and updating
+        addr = self.nodes[1].getnewaddress("", "p2sh-segwit")
+        txid = self.nodes[0].sendtoaddress(addr, 7)
+        addrinfo = self.nodes[1].getaddressinfo(addr)
+        self.nodes[0].generate(6)
+        self.sync_all()
+        vout = find_output(self.nodes[0], txid, 7)
+        psbt = self.nodes[1].createpsbt([{"txid":txid, "vout":vout}], {self.nodes[0].getnewaddress("", "p2sh-segwit"):Decimal('6.999')})
+        analyzed = self.nodes[0].analyzepsbt(psbt)
+        assert not analyzed['inputs'][0]['has_utxo'] and not analyzed['inputs'][0]['is_final'] and analyzed['inputs'][0]['next'] == 'updater' and analyzed['next'] == 'updater'
+
+        # After update with wallet, only needs signing
+        updated = self.nodes[1].walletprocesspsbt(psbt, False, 'ALL', True)['psbt']
+        analyzed = self.nodes[0].analyzepsbt(updated)
+        assert analyzed['inputs'][0]['has_utxo'] and not analyzed['inputs'][0]['is_final'] and analyzed['inputs'][0]['next'] == 'signer' and analyzed['next'] == 'signer' and analyzed['inputs'][0]['missing']['signatures'][0] == addrinfo['embedded']['witness_program']
+
+        # Check fee and size things
+        assert analyzed['fee'] == Decimal('0.001') and analyzed['estimated_vsize'] == 134 and analyzed['estimated_feerate'] == '0.00746268 BTC/kB'
+
+        # After signing and finalizing, needs extracting
+        signed = self.nodes[1].walletprocesspsbt(updated)['psbt']
+        analyzed = self.nodes[0].analyzepsbt(signed)
+        assert analyzed['inputs'][0]['has_utxo'] and analyzed['inputs'][0]['is_final'] and analyzed['next'] == 'extractor'
+
 if __name__ == '__main__':
     PSBTTest().main()