fees.cpp
1 // Copyright (c) 2010 Satoshi Nakamoto 2 // Copyright (c) 2009-present 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/block_policy_estimator.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 <util/fees.h> 19 #include <validationinterface.h> 20 21 #include <algorithm> 22 #include <array> 23 #include <cmath> 24 #include <string> 25 #include <string_view> 26 27 using common::FeeModeFromString; 28 using common::FeeModesDetail; 29 using common::InvalidEstimateModeErrorMessage; 30 using node::NodeContext; 31 32 static RPCMethod estimatesmartfee() 33 { 34 return RPCMethod{ 35 "estimatesmartfee", 36 "Estimates the approximate fee per kilobyte needed for a transaction to begin\n" 37 "confirmation within conf_target blocks if possible and return the number of blocks\n" 38 "for which the estimate is valid. Uses virtual transaction size as defined\n" 39 "in BIP 141 (witness data is discounted).\n", 40 { 41 {"conf_target", RPCArg::Type::NUM, RPCArg::Optional::NO, "Confirmation target in blocks (1 - 1008)"}, 42 {"estimate_mode", RPCArg::Type::STR, RPCArg::Default{"economical"}, "The fee estimate mode.\n" 43 + FeeModesDetail(std::string("default mode will be used"))}, 44 }, 45 RPCResult{ 46 RPCResult::Type::OBJ, "", "", 47 { 48 {RPCResult::Type::NUM, "feerate", /*optional=*/true, "estimate fee rate in " + CURRENCY_UNIT + "/kvB (only present if no errors were encountered)"}, 49 {RPCResult::Type::ARR, "errors", /*optional=*/true, "Errors encountered during processing (if there are any)", 50 { 51 {RPCResult::Type::STR, "", "error"}, 52 }}, 53 {RPCResult::Type::NUM, "blocks", "block number where estimate was found\n" 54 "The request target will be clamped between 2 and the highest target\n" 55 "fee estimation is able to return based on how long it has been running.\n" 56 "An error is returned if not enough transactions and blocks\n" 57 "have been observed to make an estimate for any number of blocks."}, 58 }}, 59 RPCExamples{ 60 HelpExampleCli("estimatesmartfee", "6") + 61 HelpExampleRpc("estimatesmartfee", "6") 62 }, 63 [](const RPCMethod& self, const JSONRPCRequest& request) -> UniValue 64 { 65 CBlockPolicyEstimator& fee_estimator = EnsureAnyFeeEstimator(request.context); 66 const NodeContext& node = EnsureAnyNodeContext(request.context); 67 const CTxMemPool& mempool = EnsureMemPool(node); 68 69 CHECK_NONFATAL(mempool.m_opts.signals)->SyncWithValidationInterfaceQueue(); 70 unsigned int max_target = fee_estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); 71 unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target); 72 FeeEstimateMode fee_mode; 73 if (!FeeModeFromString(self.Arg<std::string_view>("estimate_mode"), fee_mode)) { 74 throw JSONRPCError(RPC_INVALID_PARAMETER, InvalidEstimateModeErrorMessage()); 75 } 76 77 UniValue result(UniValue::VOBJ); 78 UniValue errors(UniValue::VARR); 79 FeeCalculation feeCalc; 80 bool conservative{fee_mode == FeeEstimateMode::CONSERVATIVE}; 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 RPCMethod estimaterawfee() 98 { 99 return RPCMethod{ 100 "estimaterawfee", 101 "WARNING: This interface is unstable and may disappear or change!\n" 102 "\nWARNING: This is an advanced API call that is tightly coupled to the specific\n" 103 "implementation of fee estimation. The parameters it can be called with\n" 104 "and the results it returns will change if the internal implementation changes.\n" 105 "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n" 106 "confirmation within conf_target blocks if possible. Uses virtual transaction size as\n" 107 "defined in BIP 141 (witness data is discounted).\n", 108 { 109 {"conf_target", RPCArg::Type::NUM, RPCArg::Optional::NO, "Confirmation target in blocks (1 - 1008)"}, 110 {"threshold", RPCArg::Type::NUM, RPCArg::Default{0.95}, "The proportion of transactions in a given feerate range that must have been\n" 111 "confirmed within conf_target in order to consider those feerates as high enough and proceed to check\n" 112 "lower buckets."}, 113 }, 114 RPCResult{ 115 RPCResult::Type::OBJ, "", "Results are returned for any horizon which tracks blocks up to the confirmation target", 116 { 117 {RPCResult::Type::OBJ, "short", /*optional=*/true, "estimate for short time horizon", 118 { 119 {RPCResult::Type::NUM, "feerate", /*optional=*/true, "estimate fee rate in " + CURRENCY_UNIT + "/kvB"}, 120 {RPCResult::Type::NUM, "decay", "exponential decay (per block) for historical moving average of confirmation data"}, 121 {RPCResult::Type::NUM, "scale", "The resolution of confirmation targets at this time horizon"}, 122 {RPCResult::Type::OBJ, "pass", /*optional=*/true, "information about the lowest range of feerates to succeed in meeting the threshold", 123 { 124 {RPCResult::Type::NUM, "startrange", "start of feerate range"}, 125 {RPCResult::Type::NUM, "endrange", "end of feerate range"}, 126 {RPCResult::Type::NUM, "withintarget", "number of txs over history horizon in the feerate range that were confirmed within target"}, 127 {RPCResult::Type::NUM, "totalconfirmed", "number of txs over history horizon in the feerate range that were confirmed at any point"}, 128 {RPCResult::Type::NUM, "inmempool", "current number of txs in mempool in the feerate range unconfirmed for at least target blocks"}, 129 {RPCResult::Type::NUM, "leftmempool", "number of txs over history horizon in the feerate range that left mempool unconfirmed after target"}, 130 }}, 131 {RPCResult::Type::OBJ, "fail", /*optional=*/true, "information about the highest range of feerates to fail to meet the threshold", 132 { 133 {RPCResult::Type::ELISION, "", ""}, 134 }}, 135 {RPCResult::Type::ARR, "errors", /*optional=*/true, "Errors encountered during processing (if there are any)", 136 { 137 {RPCResult::Type::STR, "error", ""}, 138 }}, 139 }}, 140 {RPCResult::Type::OBJ, "medium", /*optional=*/true, "estimate for medium time horizon", 141 { 142 {RPCResult::Type::ELISION, "", ""}, 143 }}, 144 {RPCResult::Type::OBJ, "long", /*optional=*/true, "estimate for long time horizon", 145 { 146 {RPCResult::Type::ELISION, "", ""}, 147 }}, 148 }}, 149 RPCExamples{ 150 HelpExampleCli("estimaterawfee", "6 0.9") 151 }, 152 [](const RPCMethod& self, const JSONRPCRequest& request) -> UniValue 153 { 154 CBlockPolicyEstimator& fee_estimator = EnsureAnyFeeEstimator(request.context); 155 const NodeContext& node = EnsureAnyNodeContext(request.context); 156 157 CHECK_NONFATAL(node.validation_signals)->SyncWithValidationInterfaceQueue(); 158 unsigned int max_target = fee_estimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE); 159 unsigned int conf_target = ParseConfirmTarget(request.params[0], max_target); 160 double threshold = 0.95; 161 if (!request.params[1].isNull()) { 162 threshold = request.params[1].get_real(); 163 } 164 if (threshold < 0 || threshold > 1) { 165 throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid threshold"); 166 } 167 168 UniValue result(UniValue::VOBJ); 169 170 for (const FeeEstimateHorizon horizon : ALL_FEE_ESTIMATE_HORIZONS) { 171 CFeeRate feeRate; 172 EstimationResult buckets; 173 174 // Only output results for horizons which track the target 175 if (conf_target > fee_estimator.HighestTargetTracked(horizon)) continue; 176 177 feeRate = fee_estimator.estimateRawFee(conf_target, threshold, horizon, &buckets); 178 UniValue horizon_result(UniValue::VOBJ); 179 UniValue errors(UniValue::VARR); 180 UniValue passbucket(UniValue::VOBJ); 181 passbucket.pushKV("startrange", round(buckets.pass.start)); 182 passbucket.pushKV("endrange", round(buckets.pass.end)); 183 passbucket.pushKV("withintarget", round(buckets.pass.withinTarget * 100.0) / 100.0); 184 passbucket.pushKV("totalconfirmed", round(buckets.pass.totalConfirmed * 100.0) / 100.0); 185 passbucket.pushKV("inmempool", round(buckets.pass.inMempool * 100.0) / 100.0); 186 passbucket.pushKV("leftmempool", round(buckets.pass.leftMempool * 100.0) / 100.0); 187 UniValue failbucket(UniValue::VOBJ); 188 failbucket.pushKV("startrange", round(buckets.fail.start)); 189 failbucket.pushKV("endrange", round(buckets.fail.end)); 190 failbucket.pushKV("withintarget", round(buckets.fail.withinTarget * 100.0) / 100.0); 191 failbucket.pushKV("totalconfirmed", round(buckets.fail.totalConfirmed * 100.0) / 100.0); 192 failbucket.pushKV("inmempool", round(buckets.fail.inMempool * 100.0) / 100.0); 193 failbucket.pushKV("leftmempool", round(buckets.fail.leftMempool * 100.0) / 100.0); 194 195 // CFeeRate(0) is used to indicate error as a return value from estimateRawFee 196 if (feeRate != CFeeRate(0)) { 197 horizon_result.pushKV("feerate", ValueFromAmount(feeRate.GetFeePerK())); 198 horizon_result.pushKV("decay", buckets.decay); 199 horizon_result.pushKV("scale", buckets.scale); 200 horizon_result.pushKV("pass", std::move(passbucket)); 201 // buckets.fail.start == -1 indicates that all buckets passed, there is no fail bucket to output 202 if (buckets.fail.start != -1) horizon_result.pushKV("fail", std::move(failbucket)); 203 } else { 204 // Output only information that is still meaningful in the event of error 205 horizon_result.pushKV("decay", buckets.decay); 206 horizon_result.pushKV("scale", buckets.scale); 207 horizon_result.pushKV("fail", std::move(failbucket)); 208 errors.push_back("Insufficient data or no feerate found which meets threshold"); 209 horizon_result.pushKV("errors", std::move(errors)); 210 } 211 result.pushKV(StringForFeeEstimateHorizon(horizon), std::move(horizon_result)); 212 } 213 return result; 214 }, 215 }; 216 } 217 218 void RegisterFeeRPCCommands(CRPCTable& t) 219 { 220 static const CRPCCommand commands[]{ 221 {"util", &estimatesmartfee}, 222 {"hidden", &estimaterawfee}, 223 }; 224 for (const auto& c : commands) { 225 t.appendCommand(c.name, &c); 226 } 227 }