feat: Temporary cap bitcoin-da fee rate

bin/citrea/tests/bitcoin/utils.rs

@@ -188,6 +188,8 @@ pub async fn spawn_bitcoin_da_service(
         utxo_selection_mode,
         rpc_timeout_secs: None,
         rpc_connect_timeout_secs: None,
+        max_fee_rate_sat_to_pay: None,
+        fee_rate_cap_duration_secs: None,
     };
 
     let (tx, rx) = tokio::sync::mpsc::unbounded_channel();

crates/bitcoin-da/src/fee.rs

@@ -99,6 +99,7 @@ impl FeeService {
     ) -> Self {
         let mempool_space_url =
             mempool_space_url.unwrap_or_else(|| DEFAULT_MEMPOOL_SPACE_URL.to_string());
+
         Self {
             client,
             network,
@@ -139,10 +140,13 @@ impl FeeService {
                         .fee_rate
                 }
             };
+
         let sat_vkb = smart_fee.map_or(1000, |rate| rate.to_sat());
+        let sat_vb = sat_vkb / 1000;
+
+        tracing::debug!("Fee rate: {sat_vb} sat/vb");
 
-        tracing::debug!("Fee rate: {} sat/vb", sat_vkb / 1000);
-        Ok(sat_vkb / 1000)
+        Ok(sat_vb)
     }
 
     /// Bump TX fee via cpfp.

crates/bitcoin-da/src/service.rs

@@ -66,7 +66,10 @@ use crate::REVEAL_OUTPUT_AMOUNT;
 
 pub(crate) type Result<T> = std::result::Result<T, BitcoinServiceError>;
 
-const POLLING_INTERVAL: u64 = 10; // seconds
+const POLLING_INTERVAL: u64 = 10; // 10 seconds
+
+const DEFAULT_FEE_RATE_CAP_DURATION_SECS: u64 = 3600; // 1 hour default cap duration
+const DEFAULT_MAX_FEE_RATE_SAT_VB: u64 = 15; // 15sat/vb default max fee rate
 
 /// Map sov Network to Bitcoin Network.
 pub fn network_to_bitcoin_network(network: &Network) -> bitcoin::Network {
@@ -124,6 +127,12 @@ pub struct BitcoinServiceConfig {
 
     /// Connection timeout for RPC in seconds
     pub rpc_connect_timeout_secs: Option<u64>,
+
+    /// Max fee rate in sat/vb
+    pub max_fee_rate_sat_to_pay: Option<u64>,
+
+    /// Fee rate cap duration in seconds
+    pub fee_rate_cap_duration_secs: Option<u64>,
 }
 
 impl citrea_common::FromEnv for BitcoinServiceConfig {
@@ -149,6 +158,12 @@ impl citrea_common::FromEnv for BitcoinServiceConfig {
             rpc_connect_timeout_secs: read_env("BITCOIN_RPC_CONNECT_TIMEOUT_SECS")
                 .ok()
                 .and_then(|v| v.parse::<u64>().ok()),
+            max_fee_rate_sat_to_pay: read_env("BITCOIN_MAX_FEE_RATE_SAT_TO_PAY")
+                .ok()
+                .and_then(|v| v.parse::<u64>().ok()),
+            fee_rate_cap_duration_secs: read_env("BITCOIN_FEE_RATE_CAP_DURATION_SECS")
+                .ok()
+                .and_then(|v| v.parse::<u64>().ok()),
         })
     }
 }
@@ -170,6 +185,8 @@ pub struct BitcoinService {
     tx_queue: Arc<Mutex<VecDeque<SignedTxPair>>>,
     pub(crate) tx_signer: TxSigner,
     utxo_selection_mode: UtxoSelectionMode,
+    max_fee_rate_sat_to_pay: u64,
+    fee_rate_cap_duration_secs: u64,
 }
 
 impl BitcoinService {
@@ -185,6 +202,8 @@ impl BitcoinService {
         reveal_tx_prefix: Vec<u8>,
         tx_backup_dir: PathBuf,
         utxo_selection_mode: UtxoSelectionMode,
+        max_fee_rate_sat_to_pay: u64,
+        fee_rate_cap_duration_secs: u64,
     ) -> Self {
         Self {
             tx_signer: TxSigner::new(client.clone()),
@@ -202,6 +221,8 @@ impl BitcoinService {
             ))),
             tx_queue: Arc::new(Mutex::new(VecDeque::new())),
             utxo_selection_mode,
+            max_fee_rate_sat_to_pay,
+            fee_rate_cap_duration_secs,
         }
     }
 
@@ -242,6 +263,12 @@ impl BitcoinService {
             .map_err(|_| BitcoinServiceError::InvalidPrivateKey)?;
 
         let utxo_selection_mode = config.utxo_selection_mode.clone().unwrap_or_default();
+        let max_fee_rate_sat_to_pay = config
+            .max_fee_rate_sat_to_pay
+            .unwrap_or(DEFAULT_MAX_FEE_RATE_SAT_VB);
+        let fee_rate_cap_duration_secs = config
+            .fee_rate_cap_duration_secs
+            .unwrap_or(DEFAULT_FEE_RATE_CAP_DURATION_SECS);
         Ok(Self::new(
             client,
             network,
@@ -253,6 +280,8 @@ impl BitcoinService {
             chain_params.reveal_tx_prefix,
             tx_backup_dir.to_path_buf(),
             utxo_selection_mode,
+            max_fee_rate_sat_to_pay,
+            fee_rate_cap_duration_secs,
         ))
     }
 
@@ -286,6 +315,7 @@ impl BitcoinService {
                     if let Some(request) = request_opt {
                         trace!("A new request is received");
 
+                        let start = std::time::Instant::now();
                         loop {
                             // Build and queue tx with retries:
                             let fee_sat_per_vbyte = match self.fee.get_fee_rate().await {
@@ -296,6 +326,26 @@ impl BitcoinService {
                                     continue;
                                 }
                             };
+
+                            // Cap fee at self.max_fee_rate_sat_to_pay for a maximum of `self.fee_rate_cap_duration_secs`.
+                            // If `self.fee_rate_cap_duration_secs` is exceeded, send transaction with fee rate above `self.max_fee_rate_sat_to_pay` anyway
+                            let elapsed = start.elapsed().as_secs();
+
+                            if fee_sat_per_vbyte > self.max_fee_rate_sat_to_pay
+                            && elapsed < self.fee_rate_cap_duration_secs {
+                                warn!("Fee rate {} sat/vb above cap of {}. Waiting (elapsed: {}s / max: {}s)", fee_sat_per_vbyte, self.max_fee_rate_sat_to_pay, elapsed, self.fee_rate_cap_duration_secs);
+                                tokio::time::sleep(Duration::from_secs(10)).await;
+                                continue;
+                            }
+
+                            if fee_sat_per_vbyte > self.max_fee_rate_sat_to_pay
+                            && elapsed >= self.fee_rate_cap_duration_secs {
+                                warn!(
+                                    "Fee rate {} sat/vb above cap of {} sat/vb, but cap duration of {}s exceeded. Sending transaction anyway",
+                                    fee_sat_per_vbyte, self.max_fee_rate_sat_to_pay, self.fee_rate_cap_duration_secs
+                                );
+                            }
+
                             match self
                                 .send_transaction_with_fee_rate(
                                     request.tx_request.clone(),