1 files changed, 35 insertions, 15 deletions

diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index b8c94d32ec..caad788591 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -806,42 +806,62 @@ UniValue estimatesmartfee(const JSONRPCRequest& request)
 {
     if (request.fHelp || request.params.size() < 1 || request.params.size() > 2)
         throw std::runtime_error(
-            "estimatesmartfee nblocks (conservative)\n"
+            "estimatesmartfee nblocks (\"estimate_mode\")\n"
             "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
             "confirmation within nblocks blocks if possible and return the number of blocks\n"
             "for which the estimate is valid. Uses virtual transaction size as defined\n"
             "in BIP 141 (witness data is discounted).\n"
             "\nArguments:\n"
-            "1. nblocks       (numeric)\n"
-            "2. conservative  (bool, optional, default=true) Whether to return a more conservative estimate which\n"
-            "                 also satisfies a longer history. A conservative estimate potentially returns a higher\n"
-            "                 feerate and is more likely to be sufficient for the desired target, but is not as\n"
-            "                 responsive to short term drops in the prevailing fee market\n"
+            "1. nblocks         (numeric) Confirmation target in blocks (1 - 1008)\n"
+            "2. \"estimate_mode\" (string, optional, default=CONSERVATIVE) The fee estimate mode.\n"
+            "                   Whether to return a more conservative estimate which also satisfies\n"
+            "                   a longer history. A conservative estimate potentially returns a\n"
+            "                   higher feerate and is more likely to be sufficient for the desired\n"
+            "                   target, but is not as responsive to short term drops in the\n"
+            "                   prevailing fee market.  Must be one of:\n"
+            "       \"UNSET\" (defaults to CONSERVATIVE)\n"
+            "       \"ECONOMICAL\"\n"
+            "       \"CONSERVATIVE\"\n"
             "\nResult:\n"
             "{\n"
-            "  \"feerate\" : x.x,     (numeric) estimate fee-per-kilobyte (in BTC)\n"
+            "  \"feerate\" : x.x,     (numeric, optional) estimate fee-per-kilobyte (in BTC)\n"
+            "  \"errors\": [ str... ] (json array of strings, optional) Errors encountered during processing\n"
             "  \"blocks\" : n         (numeric) block number where estimate was found\n"
             "}\n"
             "\n"
-            "A negative value is returned if not enough transactions and blocks\n"
+            "The request target will be clamped between 2 and the highest target\n"
+            "fee estimation is able to return based on how long it has been running.\n"
+            "An error is returned if not enough transactions and blocks\n"
             "have been observed to make an estimate for any number of blocks.\n"
             "\nExample:\n"
             + HelpExampleCli("estimatesmartfee", "6")
             );
 
-    RPCTypeCheck(request.params, {UniValue::VNUM});
-
+    RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VSTR});
+    RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
     int nBlocks = request.params[0].get_int();
+    if (nBlocks < 1 || (unsigned int)nBlocks > ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE)) {
+        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid nblocks");
+    }
     bool conservative = true;
     if (request.params.size() > 1 && !request.params[1].isNull()) {
-        RPCTypeCheckArgument(request.params[1], UniValue::VBOOL);
-        conservative = request.params[1].get_bool();
+        FeeEstimateMode fee_mode;
+        if (!FeeModeFromString(request.params[1].get_str(), fee_mode)) {
+            throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid estimate_mode parameter");
+        }
+        if (fee_mode == FeeEstimateMode::ECONOMICAL) conservative = false;
     }
 
     UniValue result(UniValue::VOBJ);
+    UniValue errors(UniValue::VARR);
     FeeCalculation feeCalc;
     CFeeRate feeRate = ::feeEstimator.estimateSmartFee(nBlocks, &feeCalc, conservative);
-    result.push_back(Pair("feerate", feeRate == CFeeRate(0) ? -1.0 : ValueFromAmount(feeRate.GetFeePerK())));
+    if (feeRate != CFeeRate(0)) {
+        result.push_back(Pair("feerate", ValueFromAmount(feeRate.GetFeePerK())));
+    } else {
+        errors.push_back("Insufficient data or no feerate found");
+        result.push_back(Pair("errors", errors));
+    }
     result.push_back(Pair("blocks", feeCalc.returnedTarget));
     return result;
 }
@@ -889,7 +909,7 @@ UniValue estimaterawfee(const JSONRPCRequest& request)
             + HelpExampleCli("estimaterawfee", "6 0.9")
             );
 
-    RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VNUM, UniValue::VNUM}, true);
+    RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VNUM}, true);
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
     int nBlocks = request.params[0].get_int();
     if (nBlocks < 1 || (unsigned int)nBlocks > ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE)) {
@@ -963,7 +983,7 @@ static const CRPCCommand commands[] =
     { "generating",         "generatetoaddress",      &generatetoaddress,      true,  {"nblocks","address","maxtries"} },
 
     { "util",               "estimatefee",            &estimatefee,            true,  {"nblocks"} },
-    { "util",               "estimatesmartfee",       &estimatesmartfee,       true,  {"nblocks", "conservative"} },
+    { "util",               "estimatesmartfee",       &estimatesmartfee,       true,  {"nblocks", "estimate_mode"} },
 
     { "hidden",             "estimaterawfee",         &estimaterawfee,         true,  {"nblocks", "threshold"} },
 };