feat: added bumpfee rpc

client/src/client.rs

@@ -260,6 +260,19 @@ pub trait RpcApi: Sized {
         self.call("addmultisigaddress", handle_defaults(&mut args, &[into_json("")?, null()]))
     }
 
+    fn bump_fee(
+        &self,
+        txid: &bitcoin::Txid,
+        options: Option<&json::BumpFeeOptions>,
+    ) -> Result<json::BumpFeeResult> {
+        let opts = match options {
+            Some(options) => Some(options.to_serializable(self.version()?)),
+            None => None,
+        };
+        let mut args = [into_json(txid)?, opt_into_json(opts)?];
+        self.call("bumpfee", handle_defaults(&mut args, &[null()]))
+    }
+
     fn load_wallet(&self, wallet: &str) -> Result<json::LoadWalletResult> {
         self.call("loadwallet", &[wallet.into()])
     }

integration_test/src/main.rs

@@ -172,6 +172,7 @@ fn main() {
     test_key_pool_refill(&cl);
     test_create_raw_transaction(&cl);
     test_fund_raw_transaction(&cl);
+    test_bump_fee(&cl);
     test_test_mempool_accept(&cl);
     test_wallet_create_funded_psbt(&cl);
     test_wallet_process_psbt(&cl);
@@ -676,6 +677,27 @@ fn test_fund_raw_transaction(cl: &Client) {
     let _ = funded.transaction().unwrap();
 }
 
+fn test_bump_fee(cl: &Client) {
+    let addr = cl.get_new_address(None, None).unwrap();
+    let txid = cl.send_to_address(&addr, btc(1), None, None, None, Some(true), None, None).unwrap();
+
+    // bump without explicit fee rate
+    let bump_fee_result_1 = cl.bump_fee(&txid, None).unwrap();
+    assert!(bump_fee_result_1.origfee < bump_fee_result_1.fee);
+
+    // bump with explicit fee rate
+    let amount_per_vbyte = Amount::from_sat(500);
+    let new_fee_rate = json::FeeRate::per_vbyte(amount_per_vbyte);
+    let options = json::BumpFeeOptions {
+        fee_rate: Some(new_fee_rate),
+        replaceable: Some(true),
+        ..Default::default()
+    };
+    let bump_fee_result_2 = cl.bump_fee(&bump_fee_result_1.txid.unwrap(), Some(&options)).unwrap();
+    let vbytes = cl.get_mempool_entry(&bump_fee_result_2.txid.unwrap()).unwrap().vsize;
+    assert_eq!(bump_fee_result_2.fee, amount_per_vbyte * vbytes);
+}
+
 fn test_test_mempool_accept(cl: &Client) {
     let options = json::ListUnspentQueryOptions {
         minimum_amount: Some(btc(2)),

json/src/lib.rs

@@ -35,6 +35,37 @@ use std::fmt;
 
 //TODO(stevenroose) consider using a Time type
 
+/// A representation of a fee rate. Bitcoin Core uses different units in different
+/// versions. To avoid burdening the user with using the correct unit, this struct
+/// provides an umambiguous way to represent the fee rate, and the lib will perform
+/// the necessary conversions.
+#[derive(Copy, Clone, PartialEq, Eq, Debug, Default)]
+pub struct FeeRate(Amount);
+
+impl FeeRate {
+    /// Construct FeeRate from the amount per vbyte
+    pub fn per_vbyte(amount_per_vbyte: Amount) -> Self {
+        // internal representation is amount per vbyte
+        Self(amount_per_vbyte)
+    }
+
+    /// Construct FeeRate from the amount per kilo-vbyte
+    pub fn per_kvbyte(amount_per_kvbyte: Amount) -> Self {
+        // internal representation is amount per vbyte, so divide by 1000
+        Self::per_vbyte(amount_per_kvbyte / 1000)
+    }
+
+    pub fn to_sat_per_vbyte(&self) -> f64 {
+        // multiply by the number of decimals to get sat
+        self.0.as_sat() as f64
+    }
+
+    pub fn to_btc_per_kvbyte(&self) -> f64 {
+        // divide by 10^8 to get btc/vbyte, then multiply by 10^3 to get btc/kbyte
+        self.0.as_sat() as f64 / 100_000.0
+    }
+}
+
 /// A module used for serde serialization of bytes in hexadecimal format.
 ///
 /// The module is compatible with the serde attribute.
@@ -1812,6 +1843,69 @@ pub struct FundRawTransactionResult {
     pub change_position: i32,
 }
 
+#[derive(Clone, PartialEq, Eq, Debug, Default)]
+pub struct BumpFeeOptions {
+    /// Confirmation target in blocks.
+    pub conf_target: Option<u16>,
+    /// Specify a fee rate instead of relying on the built-in fee estimator.
+    pub fee_rate: Option<FeeRate>,
+    /// Whether this transaction could be replaced due to BIP125 (replace-by-fee)
+    pub replaceable: Option<bool>,
+    /// The fee estimate mode
+    pub estimate_mode: Option<EstimateMode>,
+}
+
+impl BumpFeeOptions {
+    pub fn to_serializable(&self, version: usize) -> SerializableBumpFeeOptions {
+        let fee_rate = self.fee_rate.map(|x| {
+            if version < 210000 {
+                x.to_btc_per_kvbyte()
+            } else {
+                x.to_sat_per_vbyte()
+            }
+        });
+
+        SerializableBumpFeeOptions {
+            fee_rate,
+            conf_target: self.conf_target,
+            replaceable: self.replaceable,
+            estimate_mode: self.estimate_mode,
+        }
+    }
+}
+
+#[derive(Serialize, Clone, PartialEq, Debug, Default)]
+#[serde(rename_all = "camelCase")]
+pub struct SerializableBumpFeeOptions {
+    #[serde(rename = "conf_target", skip_serializing_if = "Option::is_none")]
+    /// Confirmation target in blocks.
+    pub conf_target: Option<u16>,
+    /// Specify a fee rate instead of relying on the built-in fee estimator.
+    #[serde(rename = "fee_rate")]
+    pub fee_rate: Option<f64>,
+    /// Whether this transaction could be replaced due to BIP125 (replace-by-fee)
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub replaceable: Option<bool>,
+    /// The fee estimate mode
+    #[serde(rename = "estimate_mode", skip_serializing_if = "Option::is_none")]
+    pub estimate_mode: Option<EstimateMode>,
+}
+
+#[derive(Deserialize, Clone, PartialEq, Eq, Debug)]
+#[serde(rename_all = "camelCase")]
+pub struct BumpFeeResult {
+    /// The base64-encoded unsigned PSBT of the new transaction. Only returned when wallet private keys are disabled.
+    pub psbt: Option<String>,
+    /// The id of the new transaction. Only returned when wallet private keys are enabled.
+    pub txid: Option<bitcoin::Txid>,
+    #[serde(with = "bitcoin::util::amount::serde::as_btc")]
+    pub origfee: Amount,
+    #[serde(with = "bitcoin::util::amount::serde::as_btc")]
+    pub fee: Amount,
+    /// Errors encountered during processing.
+    pub errors: Vec<String>,
+}
+
 #[derive(Deserialize, Clone, PartialEq, Eq, Debug)]
 pub struct GetBalancesResultEntry {
     #[serde(with = "bitcoin::util::amount::serde::as_btc")]
@@ -1994,3 +2088,19 @@ where
     }
     Ok(Some(res))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_fee_rate_conversion() {
+        let rate_1 = FeeRate::per_kvbyte(Amount::from_sat(10_000));
+        let rate_2 = FeeRate::per_vbyte(Amount::from_sat(10));
+        assert_eq!(rate_1, rate_2);
+
+        assert_eq!(rate_1.to_sat_per_vbyte(), 10.0);
+        // multiply 10.0 by 1e3 to get sat/kvbyte, then divide by 1e8 to get btc/kvbyte
+        assert_eq!(rate_1.to_btc_per_kvbyte(), 0.0001);
+    }
+}