Refactor fee-related structs and serialization

- Replace `u32` fields with `FeeRate` in `FeeRecommendations`
- Adjust serialization for `FeeRate` using new `fee_rate_u64_serde` and `fee_rate_f64_serde` modules
- Update tests and add a new test for `FeeRecommendations` deserialization

Signed-off-by: Yuki Kishimoto <yukikishimoto@protonmail.com>

Author: yukibtc

src/deser.rs

@@ -18,7 +18,28 @@ pub(crate) mod weight_serde {
     }
 }
 
-pub(crate) mod fee_rate_serde {
+pub(crate) mod fee_rate_u64_serde {
+    use bitcoin::FeeRate;
+    use serde::{Deserialize, Deserializer, Serializer};
+
+    pub fn serialize<S>(fee_rate: &FeeRate, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let sat_per_vb: u64 = fee_rate.to_sat_per_vb_ceil();
+        serializer.serialize_u64(sat_per_vb)
+    }
+
+    pub fn deserialize<'de, D>(deserializer: D) -> Result<FeeRate, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let sat_per_vb = u64::deserialize(deserializer)?;
+        Ok(FeeRate::from_sat_per_vb_unchecked(sat_per_vb))
+    }
+}
+
+pub(crate) mod fee_rate_f64_serde {
     use bitcoin::FeeRate;
     use serde::{Deserialize, Deserializer, Serializer};
 
@@ -27,18 +48,16 @@ pub(crate) mod fee_rate_serde {
         S: Serializer,
     {
         // Convert from sat/kwu to sat/vB
-        let sat_per_vb: f64 = fee_rate.to_sat_per_kwu() as f64 / 1000.0;
+        let sat_per_vb: f64 = fee_rate.to_sat_per_vb_ceil() as f64;
         serializer.serialize_f64(sat_per_vb)
     }
 
     pub fn deserialize<'de, D>(deserializer: D) -> Result<FeeRate, D::Error>
     where
         D: Deserializer<'de>,
     {
-        let sat_per_vb = f64::deserialize(deserializer)?;
-        // Convert from sat/vB to sat/kwu (multiply by 1000)
-        let sat_per_kwu: u64 = (sat_per_vb * 1000.0) as u64;
-        Ok(FeeRate::from_sat_per_kwu(sat_per_kwu))
+        let sat_per_vb: f64 = f64::deserialize(deserializer)?;
+        Ok(FeeRate::from_sat_per_vb_unchecked(sat_per_vb as u64))
     }
 }
 

src/response.rs

@@ -171,33 +171,38 @@ pub struct HashrateStats {
     pub current_difficulty: f64,
 }
 
-/// Bitcoin fee recommendations in sat/vB
+/// Bitcoin fee recommendations
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
 pub struct FeeRecommendations {
-    /// Fastest confirmation fee (sat/vB)
+    /// Fastest confirmation fee
     #[serde(rename = "fastestFee")]
-    pub fastest_fee: u32,
-    /// Fee for confirmation within 30 minutes (sat/vB)
+    #[serde(with = "deser::fee_rate_u64_serde")]
+    pub fastest_fee: FeeRate,
+    /// Fee for confirmation within 30 minutes
     #[serde(rename = "halfHourFee")]
-    pub half_hour_fee: u32,
-    /// Fee for confirmation within 1 hour (sat/vB)
+    #[serde(with = "deser::fee_rate_u64_serde")]
+    pub half_hour_fee: FeeRate,
+    /// Fee for confirmation within 1 hour
     #[serde(rename = "hourFee")]
-    pub hour_fee: u32,
-    /// Economy fee for slower confirmation (sat/vB)
+    #[serde(with = "deser::fee_rate_u64_serde")]
+    pub hour_fee: FeeRate,
+    /// Economy fee for slower confirmation
     #[serde(rename = "economyFee")]
-    pub economy_fee: u32,
-    /// Minimum fee (sat/vB)
+    #[serde(with = "deser::fee_rate_u64_serde")]
+    pub economy_fee: FeeRate,
+    /// Minimum fee
     #[serde(rename = "minimumFee")]
-    pub minimum_fee: u32,
+    #[serde(with = "deser::fee_rate_u64_serde")]
+    pub minimum_fee: FeeRate,
 }
 
 /// Fee histogram entry representing transactions at a specific fee rate
 #[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize, Deserialize)]
 pub struct FeeHistogramEntry {
-    /// Fee rate in sat/vB (converted from API)
-    #[serde(with = "deser::fee_rate_serde")]
+    /// Fee rate (converted from API)
+    #[serde(with = "deser::fee_rate_f64_serde")]
     pub fee_rate: FeeRate,
-    /// Virtual size of transactions at this fee rate (vB)
+    /// Virtual size of transactions at this fee rate
     #[serde(with = "deser::weight_serde")]
     pub vsize: Weight,
 }
@@ -241,7 +246,7 @@ pub struct MempoolBlockFees {
     pub total_fees: Amount,
     /// Median fee rate
     #[serde(rename = "medianFee")]
-    #[serde(with = "deser::fee_rate_serde")]
+    #[serde(with = "deser::fee_rate_f64_serde")]
     pub median_fee: FeeRate,
     /// Fee rate range
     #[serde(rename = "feeRange")]
@@ -290,6 +295,25 @@ mod tests {
         );
     }
 
+    #[test]
+    fn test_fee_recommendations_deserialization() {
+        let json_data =
+            r#"{"fastestFee":10,"halfHourFee":8,"hourFee":5,"economyFee":2,"minimumFee":1}"#;
+
+        let fees: FeeRecommendations = serde_json::from_str(json_data).unwrap();
+
+        assert_eq!(
+            fees,
+            FeeRecommendations {
+                fastest_fee: FeeRate::from_sat_per_vb_unchecked(10),
+                half_hour_fee: FeeRate::from_sat_per_vb_unchecked(8),
+                hour_fee: FeeRate::from_sat_per_vb_unchecked(5),
+                economy_fee: FeeRate::from_sat_per_vb_unchecked(2),
+                minimum_fee: FeeRate::from_sat_per_vb_unchecked(1),
+            }
+        );
+    }
+
     #[test]
     fn test_mempool_stats_deser() {
         let json_data = r#"{"count":4364,"vsize":4407712,"total_fee":7277557,"fee_histogram":[[8.687,50041],[5.135,50041],[4.07,50231]]}"#;
@@ -344,7 +368,7 @@ mod tests {
         assert_eq!(block_fee.block_v_size, 746096.5);
         assert_eq!(block_fee.n_tx, 863);
         assert_eq!(block_fee.total_fees.to_sat(), 8875608);
-        assert_eq!(block_fee.median_fee.to_sat_per_kwu(), 10796);
+        assert_eq!(block_fee.median_fee.to_sat_per_vb_ceil(), 10);
         assert_eq!(block_fee.fee_range.len(), 3);
         assert_eq!(block_fee.fee_range[0].to_sat_per_kwu(), 1000);
         assert_eq!(block_fee.fee_range[1].to_sat_per_kwu(), 2424);