refactor: make FeeDistribution fields and nested stats optional to handle incomplete data safely

Author: peteroche

packages/devkit/src/profiling/report.rs

@@ -173,10 +173,7 @@ impl ProfilingReportBuilder {
     }
 
     /// Add multiple `CpuSample` instances to the builder.
-    pub fn add_cpu_samples(
-        &mut self,
-        samples: impl IntoIterator<Item = CpuSample>,
-    ) -> &mut Self {
+    pub fn add_cpu_samples(&mut self, samples: impl IntoIterator<Item = CpuSample>) -> &mut Self {
         self.cpu_samples.extend(samples);
         self
     }
@@ -188,10 +185,7 @@ impl ProfilingReportBuilder {
     }
 
     /// Add multiple `MemSample` instances to the builder.
-    pub fn add_mem_samples(
-        &mut self,
-        samples: impl IntoIterator<Item = MemSample>,
-    ) -> &mut Self {
+    pub fn add_mem_samples(&mut self, samples: impl IntoIterator<Item = MemSample>) -> &mut Self {
         self.mem_samples.extend(samples);
         self
     }
@@ -331,12 +325,22 @@ mod tests {
 
         let t1 = Utc::now();
         builder.add_cpu_sample(
-            CpuSample::new("fee_estimator", Duration::from_millis(10), Duration::from_millis(10), 100.0)
-                .with_timestamp(t1),
+            CpuSample::new(
+                "fee_estimator",
+                Duration::from_millis(10),
+                Duration::from_millis(10),
+                100.0,
+            )
+            .with_timestamp(t1),
         );
         builder.add_cpu_sample(
-            CpuSample::new("fee_estimator", Duration::from_millis(20), Duration::from_millis(20), 100.0)
-                .with_timestamp(t1),
+            CpuSample::new(
+                "fee_estimator",
+                Duration::from_millis(20),
+                Duration::from_millis(20),
+                100.0,
+            )
+            .with_timestamp(t1),
         );
         builder.add_mem_sample(MemSample::new("fee_estimator", 2048, 1024).with_timestamp(t1));
         builder.add_mem_sample(MemSample::new("fee_estimator", 4096, 2048).with_timestamp(t1));

packages/devkit/src/protocol/fee_stats.rs

@@ -112,34 +112,36 @@ where
 /// Statistical percentile distribution of Stellar transaction fees.
 #[derive(Debug, Clone, PartialEq, Serialize, Deserialize, Default)]
 pub struct FeeDistribution {
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub min: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub max: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub mode: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p10: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p20: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p30: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p40: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p50: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p60: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p70: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p80: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p90: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p95: u64,
-    #[serde(default, deserialize_with = "deserialize_u64_lenient")]
-    pub p99: u64,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub min: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub max: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub mode: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p10: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p20: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p30: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p40: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p50: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p60: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p70: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p80: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p90: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p95: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub p99: Option<u64>,
+    #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]
+    pub transaction_count: Option<u64>,
 }
 
 /// Type alias for backward compatibility.
@@ -155,9 +157,9 @@ pub struct HorizonFeeStats {
     #[serde(default, deserialize_with = "deserialize_f64_lenient")]
     pub ledger_capacity_usage: f64,
     #[serde(default)]
-    pub fee_charged: FeeDistribution,
+    pub fee_charged: Option<FeeDistribution>,
     #[serde(default)]
-    pub max_fee: FeeDistribution,
+    pub max_fee: Option<FeeDistribution>,
 
     // Legacy/auxiliary top-level fields returned by Horizon
     #[serde(default, deserialize_with = "deserialize_opt_u64_lenient")]

packages/devkit/src/protocol/parser.rs

@@ -7,8 +7,11 @@ pub fn parse_fee_stats(json: &str) -> Result<HorizonFeeStats, DevkitError> {
     let value: Value = serde_json::from_str(json)
         .map_err(|e| DevkitError::Protocol(format!("JSON parse error: {e}")))?;
 
-    // If json is empty object or invalid, check required fields
-    if !value.is_object() || value.as_object().map_or(true, |o| o.is_empty()) {
+    let Some(obj) = value.as_object() else {
+        return Err(DevkitError::Protocol("expected JSON object".to_string()));
+    };
+
+    if obj.is_empty() {
         return Err(DevkitError::Protocol("empty JSON object".to_string()));
     }
 
@@ -42,21 +45,20 @@ pub fn validate_fee_stats(stats: &HorizonFeeStats) -> Result<(), DevkitError> {
         )));
     }
 
-    let fl = &stats.fee_charged;
-    if fl.p10 > 0 || fl.p50 > 0 || fl.p90 > 0 || fl.p99 > 0 {
-        if !(fl.p10 <= fl.p50 && fl.p50 <= fl.p90 && fl.p90 <= fl.p99) {
-            return Err(DevkitError::Protocol(format!(
-                "fee_charged percentiles must be monotonic: p10={} p50={} p90={} p99={}",
-                fl.p10, fl.p50, fl.p90, fl.p99
-            )));
+    if let Some(ref fl) = stats.fee_charged {
+        if let (Some(p10), Some(p50), Some(p90), Some(p99)) = (fl.p10, fl.p50, fl.p90, fl.p99) {
+            if !(p10 <= p50 && p50 <= p90 && p90 <= p99) {
+                return Err(DevkitError::Protocol(format!(
+                    "fee_charged percentiles must be monotonic: p10={p10} p50={p50} p90={p90} p99={p99}"
+                )));
+            }
         }
-    }
-    if fl.min > 0 || fl.mode > 0 || fl.max > 0 {
-        if !(fl.min <= fl.mode && fl.mode <= fl.max) {
-            return Err(DevkitError::Protocol(format!(
-                "fee_charged min/mode/max must be ordered: min={} mode={} max={}",
-                fl.min, fl.mode, fl.max
-            )));
+        if let (Some(min), Some(mode), Some(max)) = (fl.min, fl.mode, fl.max) {
+            if !(min <= mode && mode <= max) {
+                return Err(DevkitError::Protocol(format!(
+                    "fee_charged min/mode/max must be ordered: min={min} mode={mode} max={max}"
+                )));
+            }
         }
     }