From 418557034055f740951294e7677ae9fd5149ea9b Mon Sep 17 00:00:00 2001 From: t-bast Date: Mon, 25 Apr 2022 10:29:25 +0200 Subject: [PATCH] Add RPC to get mempool txs spending outputs We add an RPC to fetch the mempool transactions spending given outpoints. Without this RPC, application developers would need to first call `getrawmempool` which returns a long list of `txid`, then fetch each of these txs individually to check whether they spend the given outpoint(s). This RPC can later be enriched to also find confirmed transactions instead of being restricted to mempool transactions. --- doc/release-notes/release-notes-24408.md | 5 ++ src/rpc/client.cpp | 1 + src/rpc/mempool.cpp | 84 +++++++++++++++++++ src/test/fuzz/rpc.cpp | 1 + test/functional/mempool_packages.py | 6 ++ test/functional/rpc_mempool_info.py | 102 +++++++++++++++++++++++ test/functional/test_runner.py | 1 + 7 files changed, 200 insertions(+) create mode 100644 doc/release-notes/release-notes-24408.md create mode 100755 test/functional/rpc_mempool_info.py diff --git a/doc/release-notes/release-notes-24408.md b/doc/release-notes/release-notes-24408.md new file mode 100644 index 0000000000..1072ec786a --- /dev/null +++ b/doc/release-notes/release-notes-24408.md @@ -0,0 +1,5 @@ +New RPCs +-------- + +- A new `gettxspendingprevout` RPC has been added, which scans the mempool to find + transactions spending any of the given outpoints. (#24408) \ No newline at end of file diff --git a/src/rpc/client.cpp b/src/rpc/client.cpp index 23e9d4074c..ae0d0112ba 100644 --- a/src/rpc/client.cpp +++ b/src/rpc/client.cpp @@ -173,6 +173,7 @@ static const CRPCConvertParam vRPCConvertParams[] = { "setwalletflag", 1, "value" }, { "getmempoolancestors", 1, "verbose" }, { "getmempooldescendants", 1, "verbose" }, + { "gettxspendingprevout", 0, "outputs" }, { "bumpfee", 1, "options" }, { "psbtbumpfee", 1, "options" }, { "logging", 0, "include" }, diff --git a/src/rpc/mempool.cpp b/src/rpc/mempool.cpp index 27080d3881..7ee3528a63 100644 --- a/src/rpc/mempool.cpp +++ b/src/rpc/mempool.cpp @@ -587,6 +587,89 @@ static RPCHelpMan getmempoolentry() }; } +static RPCHelpMan gettxspendingprevout() +{ + return RPCHelpMan{"gettxspendingprevout", + "Scans the mempool to find transactions spending any of the given outputs", + { + {"outputs", RPCArg::Type::ARR, RPCArg::Optional::NO, "The transaction outputs that we want to check, and within each, the txid (string) vout (numeric).", + { + {"", RPCArg::Type::OBJ, RPCArg::Optional::OMITTED, "", + { + {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The transaction id"}, + {"vout", RPCArg::Type::NUM, RPCArg::Optional::NO, "The output number"}, + }, + }, + }, + }, + }, + RPCResult{ + RPCResult::Type::ARR, "", "", + { + {RPCResult::Type::OBJ, "", "", + { + {RPCResult::Type::STR_HEX, "txid", "the transaction id of the checked output"}, + {RPCResult::Type::NUM, "vout", "the vout value of the checked output"}, + {RPCResult::Type::STR_HEX, "spendingtxid", /*optional=*/true, "the transaction id of the mempool transaction spending this output (omitted if unspent)"}, + }}, + } + }, + RPCExamples{ + HelpExampleCli("gettxspendingprevout", "\"[{\\\"txid\\\":\\\"a08e6907dbbd3d809776dbfc5d82e371b764ed838b5655e72f463568df1aadf0\\\",\\\"vout\\\":3}]\"") + + HelpExampleRpc("gettxspendingprevout", "\"[{\\\"txid\\\":\\\"a08e6907dbbd3d809776dbfc5d82e371b764ed838b5655e72f463568df1aadf0\\\",\\\"vout\\\":3}]\"") + }, + [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue + { + RPCTypeCheckArgument(request.params[0], UniValue::VARR); + const UniValue& output_params = request.params[0]; + if (output_params.empty()) { + throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid parameter, outputs are missing"); + } + + std::vector prevouts; + prevouts.reserve(output_params.size()); + + for (unsigned int idx = 0; idx < output_params.size(); idx++) { + const UniValue& o = output_params[idx].get_obj(); + + RPCTypeCheckObj(o, + { + {"txid", UniValueType(UniValue::VSTR)}, + {"vout", UniValueType(UniValue::VNUM)}, + }, /*fAllowNull=*/false, /*fStrict=*/true); + + const uint256 txid(ParseHashO(o, "txid")); + const int nOutput = find_value(o, "vout").get_int(); + if (nOutput < 0) { + throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid parameter, vout cannot be negative"); + } + + prevouts.emplace_back(txid, nOutput); + } + + const CTxMemPool& mempool = EnsureAnyMemPool(request.context); + LOCK(mempool.cs); + + UniValue result{UniValue::VARR}; + + for (const COutPoint& prevout : prevouts) { + UniValue o(UniValue::VOBJ); + o.pushKV("txid", prevout.hash.ToString()); + o.pushKV("vout", (uint64_t)prevout.n); + + const CTransaction* spendingTx = mempool.GetConflictTx(prevout); + if (spendingTx != nullptr) { + o.pushKV("spendingtxid", spendingTx->GetHash().ToString()); + } + + result.push_back(o); + } + + return result; + }, + }; +} + UniValue MempoolInfoToJSON(const CTxMemPool& pool) { // Make sure this call is atomic in the pool. @@ -677,6 +760,7 @@ void RegisterMempoolRPCCommands(CRPCTable& t) {"blockchain", &getmempoolancestors}, {"blockchain", &getmempooldescendants}, {"blockchain", &getmempoolentry}, + {"blockchain", &gettxspendingprevout}, {"blockchain", &getmempoolinfo}, {"blockchain", &getrawmempool}, {"blockchain", &savemempool}, diff --git a/src/test/fuzz/rpc.cpp b/src/test/fuzz/rpc.cpp index 03a84b697d..e4e83c3f32 100644 --- a/src/test/fuzz/rpc.cpp +++ b/src/test/fuzz/rpc.cpp @@ -128,6 +128,7 @@ const std::vector RPC_COMMANDS_SAFE_FOR_FUZZING{ "getmempoolancestors", "getmempooldescendants", "getmempoolentry", + "gettxspendingprevout", "getmempoolinfo", "getmininginfo", "getnettotals", diff --git a/test/functional/mempool_packages.py b/test/functional/mempool_packages.py index 068fdc0b65..a2a2caf324 100755 --- a/test/functional/mempool_packages.py +++ b/test/functional/mempool_packages.py @@ -100,6 +100,12 @@ class MempoolPackagesTest(BitcoinTestFramework): entry = self.nodes[0].getmempoolentry(x) assert_equal(entry, mempool[x]) + # Check that gettxspendingprevout is consistent with getrawmempool + witnesstx = self.nodes[0].gettransaction(txid=x, verbose=True)['decoded'] + for tx_in in witnesstx["vin"]: + spending_result = self.nodes[0].gettxspendingprevout([ {'txid' : tx_in["txid"], 'vout' : tx_in["vout"]} ]) + assert_equal(spending_result, [ {'txid' : tx_in["txid"], 'vout' : tx_in["vout"], 'spendingtxid' : x} ]) + # Check that the descendant calculations are correct assert_equal(entry['descendantcount'], descendant_count) descendant_fees += entry['fees']['base'] diff --git a/test/functional/rpc_mempool_info.py b/test/functional/rpc_mempool_info.py new file mode 100755 index 0000000000..cd7a48d387 --- /dev/null +++ b/test/functional/rpc_mempool_info.py @@ -0,0 +1,102 @@ +#!/usr/bin/env python3 +# Copyright (c) 2014-2022 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 RPCs that retrieve information from the mempool.""" + +from test_framework.blocktools import COINBASE_MATURITY +from test_framework.test_framework import BitcoinTestFramework +from test_framework.util import ( + assert_equal, + assert_raises_rpc_error, +) +from test_framework.wallet import MiniWallet + + +class RPCMempoolInfoTest(BitcoinTestFramework): + def set_test_params(self): + self.num_nodes = 1 + + def run_test(self): + self.wallet = MiniWallet(self.nodes[0]) + self.generate(self.wallet, COINBASE_MATURITY + 1) + self.wallet.rescan_utxos() + confirmed_utxo = self.wallet.get_utxo() + + # Create a tree of unconfirmed transactions in the mempool: + # txA + # / \ + # / \ + # / \ + # / \ + # / \ + # txB txC + # / \ / \ + # / \ / \ + # txD txE txF txG + # \ / + # \ / + # txH + + def create_tx(**kwargs): + return self.wallet.send_self_transfer_multi( + from_node=self.nodes[0], + **kwargs, + ) + + txA = create_tx(utxos_to_spend=[confirmed_utxo], num_outputs=2) + txB = create_tx(utxos_to_spend=[txA["new_utxos"][0]], num_outputs=2) + txC = create_tx(utxos_to_spend=[txA["new_utxos"][1]], num_outputs=2) + txD = create_tx(utxos_to_spend=[txB["new_utxos"][0]], num_outputs=1) + txE = create_tx(utxos_to_spend=[txB["new_utxos"][1]], num_outputs=1) + txF = create_tx(utxos_to_spend=[txC["new_utxos"][0]], num_outputs=2) + txG = create_tx(utxos_to_spend=[txC["new_utxos"][1]], num_outputs=1) + txH = create_tx(utxos_to_spend=[txE["new_utxos"][0],txF["new_utxos"][0]], num_outputs=1) + txidA, txidB, txidC, txidD, txidE, txidF, txidG, txidH = [ + tx["txid"] for tx in [txA, txB, txC, txD, txE, txF, txG, txH] + ] + + mempool = self.nodes[0].getrawmempool() + assert_equal(len(mempool), 8) + for txid in [txidA, txidB, txidC, txidD, txidE, txidF, txidG, txidH]: + assert_equal(txid in mempool, True) + + self.log.info("Find transactions spending outputs") + result = self.nodes[0].gettxspendingprevout([ {'txid' : confirmed_utxo['txid'], 'vout' : 0}, {'txid' : txidA, 'vout' : 1} ]) + assert_equal(result, [ {'txid' : confirmed_utxo['txid'], 'vout' : 0, 'spendingtxid' : txidA}, {'txid' : txidA, 'vout' : 1, 'spendingtxid' : txidC} ]) + + self.log.info("Find transaction spending multiple outputs") + result = self.nodes[0].gettxspendingprevout([ {'txid' : txidE, 'vout' : 0}, {'txid' : txidF, 'vout' : 0} ]) + assert_equal(result, [ {'txid' : txidE, 'vout' : 0, 'spendingtxid' : txidH}, {'txid' : txidF, 'vout' : 0, 'spendingtxid' : txidH} ]) + + self.log.info("Find no transaction when output is unspent") + result = self.nodes[0].gettxspendingprevout([ {'txid' : txidH, 'vout' : 0} ]) + assert_equal(result, [ {'txid' : txidH, 'vout' : 0} ]) + result = self.nodes[0].gettxspendingprevout([ {'txid' : txidA, 'vout' : 5} ]) + assert_equal(result, [ {'txid' : txidA, 'vout' : 5} ]) + + self.log.info("Mixed spent and unspent outputs") + result = self.nodes[0].gettxspendingprevout([ {'txid' : txidB, 'vout' : 0}, {'txid' : txidG, 'vout' : 3} ]) + assert_equal(result, [ {'txid' : txidB, 'vout' : 0, 'spendingtxid' : txidD}, {'txid' : txidG, 'vout' : 3} ]) + + self.log.info("Unknown input fields") + assert_raises_rpc_error(-3, "Unexpected key unknown", self.nodes[0].gettxspendingprevout, [{'txid' : txidC, 'vout' : 1, 'unknown' : 42}]) + + self.log.info("Invalid vout provided") + assert_raises_rpc_error(-8, "Invalid parameter, vout cannot be negative", self.nodes[0].gettxspendingprevout, [{'txid' : txidA, 'vout' : -1}]) + + self.log.info("Invalid txid provided") + assert_raises_rpc_error(-3, "Expected type string for txid, got number", self.nodes[0].gettxspendingprevout, [{'txid' : 42, 'vout' : 0}]) + + self.log.info("Missing outputs") + assert_raises_rpc_error(-8, "Invalid parameter, outputs are missing", self.nodes[0].gettxspendingprevout, []) + + self.log.info("Missing vout") + assert_raises_rpc_error(-3, "Missing vout", self.nodes[0].gettxspendingprevout, [{'txid' : txidA}]) + + self.log.info("Missing txid") + assert_raises_rpc_error(-3, "Missing txid", self.nodes[0].gettxspendingprevout, [{'vout' : 3}]) + + +if __name__ == '__main__': + RPCMempoolInfoTest().main() diff --git a/test/functional/test_runner.py b/test/functional/test_runner.py index 7d6397d193..a27a0e2a63 100755 --- a/test/functional/test_runner.py +++ b/test/functional/test_runner.py @@ -329,6 +329,7 @@ BASE_SCRIPTS = [ 'feature_settings.py', 'rpc_getdescriptorinfo.py', 'rpc_mempool_entry_fee_fields_deprecation.py', + 'rpc_mempool_info.py', 'rpc_help.py', 'feature_dirsymlinks.py', 'feature_help.py',