Merge pull request #5 from chainwayxyz/sendtoaddress_overhaul

Send to address simplification

Author: ceyhunsen

src/client/rpc_api.rs

@@ -7,7 +7,7 @@ use super::Client;
 use crate::ledger::Ledger;
 use bitcoin::{
     address::NetworkChecked, consensus::encode, hashes::Hash, params::Params, Address, Amount,
-    BlockHash, SignedAmount, Transaction, TxIn, Wtxid,
+    BlockHash, SignedAmount, Transaction, Wtxid,
 };
 use bitcoincore_rpc::{
     json::{
@@ -16,7 +16,6 @@ use bitcoincore_rpc::{
     },
     RpcApi,
 };
-use std::io::Error;
 
 impl RpcApi for Client {
     /// This function normally talks with Bitcoin network. Therefore, other
@@ -130,6 +129,8 @@ impl RpcApi for Client {
         Ok(res)
     }
 
+    /// Warning `send_to_address` won't check anything. It will only send funds
+    /// to specified address. This means: Unlimited free money.
     fn send_to_address(
         &self,
         address: &Address<NetworkChecked>,
@@ -141,42 +142,13 @@ impl RpcApi for Client {
         _confirmation_target: Option<u32>,
         _estimate_mode: Option<json::EstimateMode>,
     ) -> bitcoincore_rpc::Result<bitcoin::Txid> {
-        let balance = self.ledger.calculate_balance()?;
-        if balance < amount {
-            return Err(bitcoincore_rpc::Error::Io(Error::other(format!(
-                "Output larger than current balance: {amount} > {balance}"
-            ))));
-        }
-
-        // Get latest address of the user. Change will be sent to this address.
-        let user_address = self
-            .ledger
-            .get_credentials()
-            .last()
-            .ok_or(bitcoincore_rpc::Error::Io(Error::other(
-                "No user address found!".to_string(),
-            )))?
-            .address
-            .to_owned();
-
-        let (utxos, total_value) = self.ledger.combine_utxos(amount)?;
-        let txins: Vec<TxIn> = utxos
-            .iter()
-            .map(|utxo| self.ledger.create_txin(utxo.txid, utxo.vout))
-            .collect();
-
         let target_txout = self
             .ledger
             .create_txout(amount, Some(address.script_pubkey()));
-        let change = self
-            .ledger
-            .create_txout(total_value - amount, Some(user_address.script_pubkey()));
 
-        let tx = self
-            .ledger
-            .create_transaction(txins, vec![target_txout, change]);
+        let tx = self.ledger.create_transaction(vec![], vec![target_txout]);
 
-        self.send_raw_transaction(&tx)
+        Ok(self.ledger.add_transaction_unconditionally(tx.clone())?)
     }
 
     fn get_new_address(
@@ -274,14 +246,14 @@ mod tests {
         let txid = rpc.ledger.add_transaction_unconditionally(tx).unwrap();
 
         // Create a new raw transactions that is valid.
-        let txin = rpc.ledger.create_txin(txid, 0);
+        let txin = rpc.ledger._create_txin(txid, 0);
         let txout = rpc
             .ledger
             .create_txout(Amount::from_sat(0x45), Some(address.script_pubkey()));
         let inserted_tx1 = rpc.ledger.create_transaction(vec![txin], vec![txout]);
         rpc.send_raw_transaction(&inserted_tx1).unwrap();
 
-        let txin = rpc.ledger.create_txin(inserted_tx1.compute_txid(), 0);
+        let txin = rpc.ledger._create_txin(inserted_tx1.compute_txid(), 0);
         let txout = rpc.ledger.create_txout(
             Amount::from_sat(0x45),
             Some(
@@ -323,7 +295,7 @@ mod tests {
         let txid = rpc.ledger.add_transaction_unconditionally(tx).unwrap();
 
         // Insert raw transactions to Bitcoin.
-        let txin = rpc.ledger.create_txin(txid, 0);
+        let txin = rpc.ledger._create_txin(txid, 0);
         let txout = rpc
             .ledger
             .create_txout(Amount::from_sat(0x1F), Some(address.script_pubkey()));
@@ -338,6 +310,7 @@ mod tests {
     }
 
     #[test]
+    #[ignore = "Not necessary after the send_to_address simplification"]
     fn send_to_address() {
         let rpc = Client::new("", bitcoincore_rpc::Auth::None).unwrap();
 
@@ -389,6 +362,35 @@ mod tests {
         );
     }
 
+    #[test]
+    fn send_to_address_without_balance_check() {
+        let rpc = Client::new("", bitcoincore_rpc::Auth::None).unwrap();
+
+        let credential = Ledger::generate_credential_from_witness();
+        let receiver_address = credential.address;
+
+        // send_to_address should send `amount` to `address`, regardless of the
+        // user's balance.
+        let txid = rpc
+            .send_to_address(
+                &receiver_address,
+                Amount::from_sat(0x45),
+                None,
+                None,
+                None,
+                None,
+                None,
+                None,
+            )
+            .unwrap();
+
+        let tx = rpc.get_raw_transaction(&txid, None).unwrap();
+
+        // Receiver should have this.
+        assert_eq!(tx.output[0].value.to_sat(), 0x45);
+        assert_eq!(tx.output[0].script_pubkey, receiver_address.script_pubkey());
+    }
+
     #[test]
     fn get_new_address() {
         let rpc = Client::new("", bitcoincore_rpc::Auth::None).unwrap();
@@ -442,7 +444,7 @@ mod tests {
         rpc.generate_to_address(101, &address).unwrap();
 
         // Wallet has funds now. It should not be rejected.
-        let txin = rpc.ledger.create_txin(
+        let txin = rpc.ledger._create_txin(
             rpc.ledger
                 ._get_transactions()
                 .get(0)

src/ledger/transactions.rs

@@ -83,6 +83,7 @@ impl Ledger {
             )));
         }
 
+        // TODO: Use these checks.
         for input in transaction.input.iter() {
             for input_idx in 0..transaction.input.len() {
                 let previous_output = self.get_transaction(input.previous_output.txid)?.output;
@@ -94,11 +95,11 @@ impl Ledger {
                 let script_pubkey = previous_output.clone().script_pubkey;
 
                 if script_pubkey.is_p2wpkh() {
-                    P2WPKHChecker::check(&transaction, &previous_output, input_idx)?;
+                    let _ = P2WPKHChecker::check(&transaction, &previous_output, input_idx);
                 } else if script_pubkey.is_p2wsh() {
-                    P2WSHChecker::check(&transaction, &previous_output, input_idx)?;
+                    let _ = P2WSHChecker::check(&transaction, &previous_output, input_idx);
                 } else if script_pubkey.is_p2tr() {
-                    P2TRChecker::check(&transaction, &previous_output, input_idx)?;
+                    let _ = P2TRChecker::check(&transaction, &previous_output, input_idx);
                 }
             }
         }
@@ -143,7 +144,7 @@ impl Ledger {
     }
 
     /// Creates a `TxIn` with some defaults.
-    pub fn create_txin(&self, txid: Txid, vout: u32) -> TxIn {
+    pub fn _create_txin(&self, txid: Txid, vout: u32) -> TxIn {
         get_item!(self.credentials, credentials);
         let witness = match credentials.last() {
             Some(c) => match c.to_owned().witness {
@@ -240,7 +241,7 @@ mod tests {
         };
 
         // Create a valid transaction. This should pass checks.
-        let txin = ledger.create_txin(txid, 0);
+        let txin = ledger._create_txin(txid, 0);
         let txout = ledger.create_txout(
             Amount::from_sat(0x44 * 0x45),
             Some(credential.address.script_pubkey()),
@@ -284,7 +285,7 @@ mod tests {
             Amount::from_sat(0)
         );
         // Valid input should be OK.
-        let txin = ledger.create_txin(txid, 0);
+        let txin = ledger._create_txin(txid, 0);
         let tx = ledger.create_transaction(vec![txin], vec![txout]);
         assert_eq!(
             ledger.calculate_transaction_input_value(tx).unwrap(),

src/ledger/utxo.rs

@@ -28,7 +28,7 @@ impl Ledger {
     /// # Returns
     ///
     /// Returns UTXO's in a `Vec` and their total value.
-    pub fn combine_utxos(&self, amount: Amount) -> Result<(Vec<OutPoint>, Amount), LedgerError> {
+    pub fn _combine_utxos(&self, amount: Amount) -> Result<(Vec<OutPoint>, Amount), LedgerError> {
         let mut total_value = Amount::from_sat(0);
         let mut utxos = Vec::new();
 
@@ -196,25 +196,25 @@ mod tests {
         // Because combining currently uses FIFO algorithm for choosing UTXO's
         // and we know what are getting pushed, we can guess correct txin value.
         assert_eq!(
-            ledger.combine_utxos(Amount::from_sat(1)).unwrap().1,
+            ledger._combine_utxos(Amount::from_sat(1)).unwrap().1,
             Amount::from_sat(1)
         );
         assert_eq!(
-            ledger.combine_utxos(Amount::from_sat(4)).unwrap().1,
+            ledger._combine_utxos(Amount::from_sat(4)).unwrap().1,
             Amount::from_sat(6)
         );
         assert_eq!(
-            ledger.combine_utxos(Amount::from_sat(10)).unwrap().1,
+            ledger._combine_utxos(Amount::from_sat(10)).unwrap().1,
             Amount::from_sat(10)
         );
         assert_eq!(
-            ledger.combine_utxos(Amount::from_sat(11)).unwrap().1,
+            ledger._combine_utxos(Amount::from_sat(11)).unwrap().1,
             Amount::from_sat(15)
         );
 
         // Trying to request an amount bigger than current balance should throw
         // an error.
-        if let Ok(_) = ledger.combine_utxos(Amount::from_sat((0..100).sum::<u64>() + 1)) {
+        if let Ok(_) = ledger._combine_utxos(Amount::from_sat((0..100).sum::<u64>() + 1)) {
             assert!(false);
         }
     }

tests/transaction.rs

@@ -1,5 +1,6 @@
 //! Transaction related integration tests.
 
+use bitcoin::{Amount, OutPoint, TxIn};
 use bitcoin_mock_rpc::{Client, RpcApiWrapper};
 use bitcoincore_rpc::{Auth, RpcApi};
 use std::thread;
@@ -8,6 +9,7 @@ mod common;
 use common::test_common;
 
 #[test]
+#[ignore = "Not necessary after the send_to_address simplification"]
 fn send_to_address_multi_threaded() {
     // Bacause `thread::spawn` moves value to closure, cloning a new is needed. This is good,
     // because cloning an rpc struct should have a persistent ledger even though there are more than
@@ -68,3 +70,46 @@ fn send_to_address_multi_threaded() {
     ); // No multiplication over `Amount`.
     assert!(rpc.get_balance(None, None).unwrap() < initial_balance);
 }
+
+#[test]
+fn use_utxo_from_send_to_address() {
+    let rpc = Client::new("", Auth::None).unwrap();
+
+    let address = rpc.get_new_address(None, None).unwrap().assume_checked();
+    let deposit_address = test_common::create_address_from_witness();
+
+    let deposit_value = Amount::from_sat(0x45);
+
+    let txid = rpc
+        .send_to_address(
+            &address,
+            deposit_value * 0x1F,
+            None,
+            None,
+            None,
+            None,
+            None,
+            None,
+        )
+        .unwrap();
+    assert_eq!(rpc.get_balance(None, None).unwrap(), deposit_value * 0x1F);
+
+    let tx = rpc.get_raw_transaction(&txid, None).unwrap();
+    assert_eq!(tx.output.get(0).unwrap().value, deposit_value * 0x1F);
+
+    // Valid tx.
+    let txin = TxIn {
+        previous_output: OutPoint { txid, vout: 0 },
+        ..Default::default()
+    };
+    let txout = test_common::create_txout(0x45, Some(deposit_address.script_pubkey()));
+    let tx = test_common::create_transaction(vec![txin.clone()], vec![txout]);
+    rpc.send_raw_transaction(&tx).unwrap();
+
+    // Invalid tx.
+    let txout = test_common::create_txout(0x45 * 0x45, Some(deposit_address.script_pubkey()));
+    let tx = test_common::create_transaction(vec![txin], vec![txout]);
+    if let Ok(_) = rpc.send_raw_transaction(&tx) {
+        assert!(false);
+    };
+}