fix(dpp): desiarilization of data contract JSON with token configuration (#2857)

Author: shumkov

packages/rs-dpp/src/data_contract/associated_token/token_perpetual_distribution/distribution_function/mod.rs

@@ -159,7 +159,9 @@ pub enum DistributionFunction {
     ///
     /// # Example
     /// - Emit 100 tokens per block for the first 1,000 blocks, then 50 tokens per block thereafter.
-    Stepwise(BTreeMap<u64, TokenAmount>),
+    Stepwise(
+        #[serde(deserialize_with = "deserialize_u64_token_amount_map")] BTreeMap<u64, TokenAmount>,
+    ),
 
     /// Emits tokens following a linear function that can increase or decrease over time
     /// with fractional precision.
@@ -558,6 +560,45 @@ pub enum DistributionFunction {
     },
 }
 
+// Custom deserializer helper that accepts both key shapes for JSON and other serde formats:
+// - BTreeMap<u64, TokenAmount>                // numeric timestamp/step keys
+// - BTreeMap<String, TokenAmount>             // numeric-looking strings as keys
+// The function normalizes both into `BTreeMap<u64, TokenAmount>`. If a string key
+// cannot be parsed as `u64`, deserialization fails with a serde error.
+use serde::de::Deserializer;
+fn deserialize_u64_token_amount_map<'de, D>(
+    deserializer: D,
+) -> Result<BTreeMap<u64, TokenAmount>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    // Untagged enum tries variants in order: attempt numeric keys first,
+    // then fallback to string keys.
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum U64OrStrMap<V> {
+        // JSON: { 0: 100, 10: 50 }
+        U64(BTreeMap<u64, V>),
+        // JSON: { "0": 100, "10": 50 }
+        Str(BTreeMap<String, V>),
+    }
+
+    let helper: U64OrStrMap<TokenAmount> = U64OrStrMap::deserialize(deserializer)?;
+    match helper {
+        // Already numeric keys; return as-is
+        U64OrStrMap::U64(m) => Ok(m),
+        // Parse numeric-looking string keys into u64, preserving values
+        U64OrStrMap::Str(sm) => sm
+            .into_iter()
+            .map(|(k, v)| {
+                k.parse::<u64>()
+                    .map_err(serde::de::Error::custom)
+                    .map(|kk| (kk, v))
+            })
+            .collect(),
+    }
+}
+
 impl fmt::Display for DistributionFunction {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {

packages/rs-dpp/src/data_contract/associated_token/token_pre_programmed_distribution/v0/mod.rs

@@ -10,6 +10,7 @@ use std::fmt;
 #[derive(Serialize, Deserialize, Decode, Encode, Debug, Clone, PartialEq, Eq)]
 #[serde(rename_all = "camelCase")]
 pub struct TokenPreProgrammedDistributionV0 {
+    #[serde(deserialize_with = "deserialize_ts_to_id_amount_map")]
     pub distributions: BTreeMap<TimestampMillis, BTreeMap<Identifier, TokenAmount>>,
 }
 
@@ -26,3 +27,46 @@ impl fmt::Display for TokenPreProgrammedDistributionV0 {
         write!(f, "}}")
     }
 }
+
+use serde::de::Deserializer;
+
+// Custom deserializer for `distributions` that tolerates two JSON shapes:
+// - a map keyed by timestamp millis as numbers (u64)
+// - a map keyed by timestamp millis as strings (e.g. "1735689600000")
+// It normalizes both into `BTreeMap<u64, V>` where V is the inner value map
+// (`BTreeMap<Identifier, TokenAmount>` here). If a string key cannot be parsed
+// as `u64`, deserialization fails with a serde error. Using `BTreeMap` keeps
+// keys ordered by timestamp.
+fn deserialize_ts_to_id_amount_map<'de, D>(
+    deserializer: D,
+) -> Result<BTreeMap<TimestampMillis, BTreeMap<Identifier, TokenAmount>>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    // Untagged enum attempts the variants in order: first try a map with u64
+    // keys; if that doesn't match, try a map with string keys.
+    #[derive(Deserialize)]
+    #[serde(untagged)]
+    enum U64OrStrTs<V> {
+        // JSON: { 1735689600000: { <id>: <amount>, ... }, ... }
+        U64(BTreeMap<TimestampMillis, V>),
+        // JSON: { "1735689600000": { <id>: <amount>, ... }, ... }
+        Str(BTreeMap<String, V>),
+    }
+
+    let helper: U64OrStrTs<BTreeMap<Identifier, TokenAmount>> =
+        U64OrStrTs::deserialize(deserializer)?;
+    match helper {
+        // Already has numeric timestamp keys; return as-is
+        U64OrStrTs::U64(m) => Ok(m),
+        // Convert string timestamp keys into u64, preserving values unchanged
+        U64OrStrTs::Str(sm) => sm
+            .into_iter()
+            .map(|(k, v)| {
+                k.parse::<u64>()
+                    .map_err(serde::de::Error::custom)
+                    .map(|ts| (ts, v))
+            })
+            .collect(),
+    }
+}