fees.cpp
1 // Copyright (c) 2010 Satoshi Nakamoto 2 // Copyright (c) 2009-2022 The Bitcoin Core developers 3 // Distributed under the MIT software license, see the accompanying 4 // file COPYING or http://www.opensource.org/licenses/mit-license.php. 5 6 #include <common/messages.h> 7 #include <core_io.h> 8 #include <node/context.h> 9 #include <policy/feerate.h> 10 #include <policy/fees.h> 11 #include <rpc/protocol.h> 12 #include <rpc/request.h> 13 #include <rpc/server.h> 14 #include <rpc/server_util.h> 15 #include <rpc/util.h> 16 #include <txmempool.h> 17 #include <univalue.h> 18 #include <validationinterface.h> 19 20 #include <algorithm> 21 #include <array> 22 #include <cmath> 23 #include <string> 24 25 using common::FeeModeFromString; 26 using common::FeeModesDetail; 27 using common::InvalidEstimateModeErrorMessage; 28 using node::NodeContext; 29 30 static RPCHelpMan estimatesmartfee() 31 { 32 return RPCHelpMan{"estimatesmartfee", 33 "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n" 34 "confirmation within conf_target blocks if possible and return the number of blocks\n" 35 "for which the estimate is valid. Uses virtual transaction size as defined\n" 36 "in BIP 141 (witness data is discounted).\n", 37 { 38 {"conf_target", RPCArg::Type::NUM, RPCArg::Optional::NO, "Confirmation target in blocks (1 - 1008)"}, 39 {"estimate_mode", RPCArg::Type::STR, RPCArg::Default{"economical"}, "The fee estimate mode.\n" 40 + FeeModesDetail(std::string("default mode will be used"))}, 41 }, 42 RPCResult{ 43 RPCResult::Type::OBJ, "", "", 44 { 45 {RPCResult::Type::NUM, "feerate", /*optional=*/true, "estimate fee rate in " + CURRENCY_UNIT + "/kvB (only present if no errors were encountered)"}, 46 {RPCResult::Type::ARR, "errors", /*optional=*/true, "Errors encountered during processing (if there are any)", 47 { 48 {RPCResult::Type::STR, "", "error"}, 49 }}, 50 {RPCResult::Type::NUM, "blocks", "block number where estimate was found\n" 51 "The request target will be clamped between 2 and the highest target\n" 52 "fee estimation is able to return based on how long it has been running.\n" 53 "An error is returned if not enough transactions and blocks\n" 54 "have been observed to make an estimate for any number of blocks."}, 55 }}, 56 RPCExamples{ 57 HelpExampleCli("estimatesmartfee", "6") + 58 HelpExampleRpc("estimatesmartfee", "6") 59 }, 60 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue 61 { 62 CBlockPolicyEstimator& fee_estimator = EnsureAnyFeeEstimator(request.context); 63 const NodeContext& node = EnsureAnyNodeContext(request.context); 64 const CTxMemPool& mempool = EnsureMemPool(node); 65 66 CHECK_NONFATAL(mempool.m_opts.signals)->SyncWithValidationInterfaceQueue(); 67 unsigned int max_target = fee_estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); 68 unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target); 69 bool conservative = false; 70 if (!request.params[1].isNull()) { 71 FeeEstimateMode fee_mode; 72 if (!FeeModeFromString(request.params[1].get_str(), fee_mode)) { 73 throw JSONRPCError(RPC_INVALID_PARAMETER, InvalidEstimateModeErrorMessage()); 74 } 75 if (fee_mode == FeeEstimateMode::CONSERVATIVE) conservative = true; 76 } 77 78 UniValue result(UniValue::VOBJ); 79 UniValue errors(UniValue::VARR); 80 FeeCalculation feeCalc; 81 CFeeRate feeRate{fee_estimator.estimateSmartFee(conf_target, &feeCalc, conservative)}; 82 if (feeRate != CFeeRate(0)) { 83 CFeeRate min_mempool_feerate{mempool.GetMinFee()}; 84 CFeeRate min_relay_feerate{mempool.m_opts.min_relay_feerate}; 85 feeRate = std::max({feeRate, min_mempool_feerate, min_relay_feerate}); 86 result.pushKV("feerate", ValueFromAmount(feeRate.GetFeePerK())); 87 } else { 88 errors.push_back("Insufficient data or no feerate found"); 89 result.pushKV("errors", std::move(errors)); 90 } 91 result.pushKV("blocks", feeCalc.returnedTarget); 92 return result; 93 }, 94 }; 95 } 96 97 static RPCHelpMan estimaterawfee() 98 { 99 return RPCHelpMan{"estimaterawfee", 100 "\nWARNING: This interface is unstable and may disappear or change!\n" 101 "\nWARNING: This is an advanced API call that is tightly coupled to the specific\n" 102 "implementation of fee estimation. The parameters it can be called with\n" 103 "and the results it returns will change if the internal implementation changes.\n" 104 "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n" 105 "confirmation within conf_target blocks if possible. Uses virtual transaction size as\n" 106 "defined in BIP 141 (witness data is discounted).\n", 107 { 108 {"conf_target", RPCArg::Type::NUM, RPCArg::Optional::NO, "Confirmation target in blocks (1 - 1008)"}, 109 {"threshold", RPCArg::Type::NUM, RPCArg::Default{0.95}, "The proportion of transactions in a given feerate range that must have been\n" 110 "confirmed within conf_target in order to consider those feerates as high enough and proceed to check\n" 111 "lower buckets."}, 112 }, 113 RPCResult{ 114 RPCResult::Type::OBJ, "", "Results are returned for any horizon which tracks blocks up to the confirmation target", 115 { 116 {RPCResult::Type::OBJ, "short", /*optional=*/true, "estimate for short time horizon", 117 { 118 {RPCResult::Type::NUM, "feerate", /*optional=*/true, "estimate fee rate in " + CURRENCY_UNIT + "/kvB"}, 119 {RPCResult::Type::NUM, "decay", "exponential decay (per block) for historical moving average of confirmation data"}, 120 {RPCResult::Type::NUM, "scale", "The resolution of confirmation targets at this time horizon"}, 121 {RPCResult::Type::OBJ, "pass", /*optional=*/true, "information about the lowest range of feerates to succeed in meeting the threshold", 122 { 123 {RPCResult::Type::NUM, "startrange", "start of feerate range"}, 124 {RPCResult::Type::NUM, "endrange", "end of feerate range"}, 125 {RPCResult::Type::NUM, "withintarget", "number of txs over history horizon in the feerate range that were confirmed within target"}, 126 {RPCResult::Type::NUM, "totalconfirmed", "number of txs over history horizon in the feerate range that were confirmed at any point"}, 127 {RPCResult::Type::NUM, "inmempool", "current number of txs in mempool in the feerate range unconfirmed for at least target blocks"}, 128 {RPCResult::Type::NUM, "leftmempool", "number of txs over history horizon in the feerate range that left mempool unconfirmed after target"}, 129 }}, 130 {RPCResult::Type::OBJ, "fail", /*optional=*/true, "information about the highest range of feerates to fail to meet the threshold", 131 { 132 {RPCResult::Type::ELISION, "", ""}, 133 }}, 134 {RPCResult::Type::ARR, "errors", /*optional=*/true, "Errors encountered during processing (if there are any)", 135 { 136 {RPCResult::Type::STR, "error", ""}, 137 }}, 138 }}, 139 {RPCResult::Type::OBJ, "medium", /*optional=*/true, "estimate for medium time horizon", 140 { 141 {RPCResult::Type::ELISION, "", ""}, 142 }}, 143 {RPCResult::Type::OBJ, "long", /*optional=*/true, "estimate for long time horizon", 144 { 145 {RPCResult::Type::ELISION, "", ""}, 146 }}, 147 }}, 148 RPCExamples{ 149 HelpExampleCli("estimaterawfee", "6 0.9") 150 }, 151 [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue 152 { 153 CBlockPolicyEstimator& fee_estimator = EnsureAnyFeeEstimator(request.context); 154 const NodeContext& node = EnsureAnyNodeContext(request.context); 155 156 CHECK_NONFATAL(node.validation_signals)->SyncWithValidationInterfaceQueue(); 157 unsigned int max_target = fee_estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); 158 unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target); 159 double threshold = 0.95; 160 if (!request.params[1].isNull()) { 161 threshold = request.params[1].get_real(); 162 } 163 if (threshold < 0 || threshold > 1) { 164 throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid threshold"); 165 } 166 167 UniValue result(UniValue::VOBJ); 168 169 for (const FeeEstimateHorizon horizon : ALL_FEE_ESTIMATE_HORIZONS) { 170 CFeeRate feeRate; 171 EstimationResult buckets; 172 173 // Only output results for horizons which track the target 174 if (conf_target > fee_estimator.HighestTargetTracked(horizon)) continue; 175 176 feeRate = fee_estimator.estimateRawFee(conf_target, threshold, horizon, &buckets); 177 UniValue horizon_result(UniValue::VOBJ); 178 UniValue errors(UniValue::VARR); 179 UniValue passbucket(UniValue::VOBJ); 180 passbucket.pushKV("startrange", round(buckets.pass.start)); 181 passbucket.pushKV("endrange", round(buckets.pass.end)); 182 passbucket.pushKV("withintarget", round(buckets.pass.withinTarget * 100.0) / 100.0); 183 passbucket.pushKV("totalconfirmed", round(buckets.pass.totalConfirmed * 100.0) / 100.0); 184 passbucket.pushKV("inmempool", round(buckets.pass.inMempool * 100.0) / 100.0); 185 passbucket.pushKV("leftmempool", round(buckets.pass.leftMempool * 100.0) / 100.0); 186 UniValue failbucket(UniValue::VOBJ); 187 failbucket.pushKV("startrange", round(buckets.fail.start)); 188 failbucket.pushKV("endrange", round(buckets.fail.end)); 189 failbucket.pushKV("withintarget", round(buckets.fail.withinTarget * 100.0) / 100.0); 190 failbucket.pushKV("totalconfirmed", round(buckets.fail.totalConfirmed * 100.0) / 100.0); 191 failbucket.pushKV("inmempool", round(buckets.fail.inMempool * 100.0) / 100.0); 192 failbucket.pushKV("leftmempool", round(buckets.fail.leftMempool * 100.0) / 100.0); 193 194 // CFeeRate(0) is used to indicate error as a return value from estimateRawFee 195 if (feeRate != CFeeRate(0)) { 196 horizon_result.pushKV("feerate", ValueFromAmount(feeRate.GetFeePerK())); 197 horizon_result.pushKV("decay", buckets.decay); 198 horizon_result.pushKV("scale", (int)buckets.scale); 199 horizon_result.pushKV("pass", std::move(passbucket)); 200 // buckets.fail.start == -1 indicates that all buckets passed, there is no fail bucket to output 201 if (buckets.fail.start != -1) horizon_result.pushKV("fail", std::move(failbucket)); 202 } else { 203 // Output only information that is still meaningful in the event of error 204 horizon_result.pushKV("decay", buckets.decay); 205 horizon_result.pushKV("scale", (int)buckets.scale); 206 horizon_result.pushKV("fail", std::move(failbucket)); 207 errors.push_back("Insufficient data or no feerate found which meets threshold"); 208 horizon_result.pushKV("errors", std::move(errors)); 209 } 210 result.pushKV(StringForFeeEstimateHorizon(horizon), std::move(horizon_result)); 211 } 212 return result; 213 }, 214 }; 215 } 216 217 void RegisterFeeRPCCommands(CRPCTable& t) 218 { 219 static const CRPCCommand commands[]{ 220 {"util", &estimatesmartfee}, 221 {"hidden", &estimaterawfee}, 222 }; 223 for (const auto& c : commands) { 224 t.appendCommand(c.name, &c); 225 } 226 }