[rpc] refactor: consolidate sendmany and sendtoaddress code

The only new behavior is some error codes are changed from -4 to -6.

Author: Sjors

doc/release-notes-18202.md

@@ -0,0 +1,8 @@
+Low-level RPC Changes
+---------------------
+
+- To make RPC `sendtoaddress` more consistent with `sendmany` the following error
+    `sendtoaddress` codes were changed from `-4` to `-6`:
+  - Insufficient funds
+  - Fee estimation failed
+  - Transaction has too long of a mempool chain

src/wallet/rpcwallet.cpp

@@ -321,36 +321,54 @@ static UniValue setlabel(const JSONRPCRequest& request)
     return NullUniValue;
 }
 
+void ParseRecipients(const UniValue& address_amounts, const UniValue& subtract_fee_outputs, std::vector<CRecipient> &recipients) {
+    std::set<CTxDestination> destinations;
+    int i = 0;
+    for (const std::string& address: address_amounts.getKeys()) {
+        CTxDestination dest = DecodeDestination(address);
+        if (!IsValidDestination(dest)) {
+            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, std::string("Invalid Bitcoin address: ") + address);
+        }
 
-static CTransactionRef SendMoney(CWallet* const pwallet, const CTxDestination& address, CAmount nValue, bool fSubtractFeeFromAmount, const CCoinControl& coin_control, mapValue_t mapValue)
-{
-    CAmount curBalance = pwallet->GetBalance(0, coin_control.m_avoid_address_reuse).m_mine_trusted;
+        if (destinations.count(dest)) {
+            throw JSONRPCError(RPC_INVALID_PARAMETER, std::string("Invalid parameter, duplicated address: ") + address);
+        }
+        destinations.insert(dest);
 
-    // Check amount
-    if (nValue <= 0)
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid amount");
+        CScript script_pub_key = GetScriptForDestination(dest);
+        CAmount amount = AmountFromValue(address_amounts[i++]);
 
-    if (nValue > curBalance)
-        throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, "Insufficient funds");
+        bool subtract_fee = false;
+        for (unsigned int idx = 0; idx < subtract_fee_outputs.size(); idx++) {
+            const UniValue& addr = subtract_fee_outputs[idx];
+            if (addr.get_str() == address) {
+                subtract_fee = true;
+            }
+        }
 
-    // Parse Bitcoin address
-    CScript scriptPubKey = GetScriptForDestination(address);
+        CRecipient recipient = {script_pub_key, amount, subtract_fee};
+        recipients.push_back(recipient);
+    }
+}
+
+UniValue SendMoney(CWallet* const pwallet, const CCoinControl &coin_control, std::vector<CRecipient> &recipients, mapValue_t map_value)
+{
+    EnsureWalletIsUnlocked(pwallet);
 
-    // Create and send the transaction
+    // Shuffle recipient list
+    std::shuffle(recipients.begin(), recipients.end(), FastRandomContext());
+
+    // Send
     CAmount nFeeRequired = 0;
-    bilingual_str error;
-    std::vector<CRecipient> vecSend;
     int nChangePosRet = -1;
-    CRecipient recipient = {scriptPubKey, nValue, fSubtractFeeFromAmount};
-    vecSend.push_back(recipient);
+    bilingual_str error;
     CTransactionRef tx;
-    if (!pwallet->CreateTransaction(vecSend, tx, nFeeRequired, nChangePosRet, error, coin_control)) {
-        if (!fSubtractFeeFromAmount && nValue + nFeeRequired > curBalance)
-            error = strprintf(Untranslated("Error: This transaction requires a transaction fee of at least %s"), FormatMoney(nFeeRequired));
-        throw JSONRPCError(RPC_WALLET_ERROR, error.original);
+    bool fCreated = pwallet->CreateTransaction(recipients, tx, nFeeRequired, nChangePosRet, error, coin_control, !pwallet->IsWalletFlagSet(WALLET_FLAG_DISABLE_PRIVATE_KEYS));
+    if (!fCreated) {
+        throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, error.original);
     }
-    pwallet->CommitTransaction(tx, std::move(mapValue), {} /* orderForm */);
-    return tx;
+    pwallet->CommitTransaction(tx, std::move(map_value), {} /* orderForm */);
+    return tx->GetHash().GetHex();
 }
 
 static UniValue sendtoaddress(const JSONRPCRequest& request)
@@ -398,16 +416,6 @@ static UniValue sendtoaddress(const JSONRPCRequest& request)
 
     LOCK(pwallet->cs_wallet);
 
-    CTxDestination dest = DecodeDestination(request.params[0].get_str());
-    if (!IsValidDestination(dest)) {
-        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid address");
-    }
-
-    // Amount
-    CAmount nAmount = AmountFromValue(request.params[1]);
-    if (nAmount <= 0)
-        throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount for send");
-
     // Wallet comments
     mapValue_t mapValue;
     if (!request.params[2].isNull() && !request.params[2].get_str().empty())
@@ -441,8 +449,18 @@ static UniValue sendtoaddress(const JSONRPCRequest& request)
 
     EnsureWalletIsUnlocked(pwallet);
 
-    CTransactionRef tx = SendMoney(pwallet, dest, nAmount, fSubtractFeeFromAmount, coin_control, std::move(mapValue));
-    return tx->GetHash().GetHex();
+    UniValue address_amounts(UniValue::VOBJ);
+    const std::string address = request.params[0].get_str();
+    address_amounts.pushKV(address, request.params[1]);
+    UniValue subtractFeeFromAmount(UniValue::VARR);
+    if (fSubtractFeeFromAmount) {
+        subtractFeeFromAmount.push_back(address);
+    }
+
+    std::vector<CRecipient> recipients;
+    ParseRecipients(address_amounts, subtractFeeFromAmount, recipients);
+
+    return SendMoney(pwallet, coin_control, recipients, mapValue);
 }
 
 static UniValue listaddressgroupings(const JSONRPCRequest& request)
@@ -840,52 +858,10 @@ static UniValue sendmany(const JSONRPCRequest& request)
         }
     }
 
-    std::set<CTxDestination> destinations;
-    std::vector<CRecipient> vecSend;
+    std::vector<CRecipient> recipients;
+    ParseRecipients(sendTo, subtractFeeFromAmount, recipients);
 
-    std::vector<std::string> keys = sendTo.getKeys();
-    for (const std::string& name_ : keys) {
-        CTxDestination dest = DecodeDestination(name_);
-        if (!IsValidDestination(dest)) {
-            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, std::string("Invalid Bitcoin address: ") + name_);
-        }
-
-        if (destinations.count(dest)) {
-            throw JSONRPCError(RPC_INVALID_PARAMETER, std::string("Invalid parameter, duplicated address: ") + name_);
-        }
-        destinations.insert(dest);
-
-        CScript scriptPubKey = GetScriptForDestination(dest);
-        CAmount nAmount = AmountFromValue(sendTo[name_]);
-        if (nAmount <= 0)
-            throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount for send");
-
-        bool fSubtractFeeFromAmount = false;
-        for (unsigned int idx = 0; idx < subtractFeeFromAmount.size(); idx++) {
-            const UniValue& addr = subtractFeeFromAmount[idx];
-            if (addr.get_str() == name_)
-                fSubtractFeeFromAmount = true;
-        }
-
-        CRecipient recipient = {scriptPubKey, nAmount, fSubtractFeeFromAmount};
-        vecSend.push_back(recipient);
-    }
-
-    EnsureWalletIsUnlocked(pwallet);
-
-    // Shuffle recipient list
-    std::shuffle(vecSend.begin(), vecSend.end(), FastRandomContext());
-
-    // Send
-    CAmount nFeeRequired = 0;
-    int nChangePosRet = -1;
-    bilingual_str error;
-    CTransactionRef tx;
-    bool fCreated = pwallet->CreateTransaction(vecSend, tx, nFeeRequired, nChangePosRet, error, coin_control);
-    if (!fCreated)
-        throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, error.original);
-    pwallet->CommitTransaction(tx, std::move(mapValue), {} /* orderForm */);
-    return tx->GetHash().GetHex();
+    return SendMoney(pwallet, coin_control, recipients, std::move(mapValue));
 }
 
 static UniValue addmultisigaddress(const JSONRPCRequest& request)

test/functional/wallet_basic.py

@@ -119,7 +119,7 @@ def run_test(self):
         assert_raises_rpc_error(-8, "Invalid parameter, expected locked output", self.nodes[2].lockunspent, True, [unspent_0])
         self.nodes[2].lockunspent(False, [unspent_0])
         assert_raises_rpc_error(-8, "Invalid parameter, output already locked", self.nodes[2].lockunspent, False, [unspent_0])
-        assert_raises_rpc_error(-4, "Insufficient funds", self.nodes[2].sendtoaddress, self.nodes[2].getnewaddress(), 20)
+        assert_raises_rpc_error(-6, "Insufficient funds", self.nodes[2].sendtoaddress, self.nodes[2].getnewaddress(), 20)
         assert_equal([unspent_0], self.nodes[2].listlockunspent())
         self.nodes[2].lockunspent(True, [unspent_0])
         assert_equal(len(self.nodes[2].listlockunspent()), 0)
@@ -309,6 +309,9 @@ def run_test(self):
         assert_equal(tx_obj['amount'], Decimal('-0.0001'))
 
         # General checks for errors from incorrect inputs
+        # This will raise an exception because the amount is negative
+        assert_raises_rpc_error(-3, "Amount out of range", self.nodes[0].sendtoaddress, self.nodes[2].getnewaddress(), "-1")
+
         # This will raise an exception because the amount type is wrong
         assert_raises_rpc_error(-3, "Invalid amount", self.nodes[0].sendtoaddress, self.nodes[2].getnewaddress(), "1f-4")
 
@@ -468,7 +471,7 @@ def run_test(self):
 
         node0_balance = self.nodes[0].getbalance()
         # With walletrejectlongchains we will not create the tx and store it in our wallet.
-        assert_raises_rpc_error(-4, "Transaction has too long of a mempool chain", self.nodes[0].sendtoaddress, sending_addr, node0_balance - Decimal('0.01'))
+        assert_raises_rpc_error(-6, "Transaction has too long of a mempool chain", self.nodes[0].sendtoaddress, sending_addr, node0_balance - Decimal('0.01'))
 
         # Verify nothing new in wallet
         assert_equal(total_txs, len(self.nodes[0].listtransactions("*", 99999)))

test/functional/wallet_fallbackfee.py

@@ -22,7 +22,7 @@ def run_test(self):
 
         # test sending a tx with disabled fallback fee (must fail)
         self.restart_node(0, extra_args=["-fallbackfee=0"])
-        assert_raises_rpc_error(-4, "Fee estimation failed", lambda: self.nodes[0].sendtoaddress(self.nodes[0].getnewaddress(), 1))
+        assert_raises_rpc_error(-6, "Fee estimation failed", lambda: self.nodes[0].sendtoaddress(self.nodes[0].getnewaddress(), 1))
         assert_raises_rpc_error(-4, "Fee estimation failed", lambda: self.nodes[0].fundrawtransaction(self.nodes[0].createrawtransaction([], {self.nodes[0].getnewaddress(): 1})))
         assert_raises_rpc_error(-6, "Fee estimation failed", lambda: self.nodes[0].sendmany("", {self.nodes[0].getnewaddress(): 1}))