fix: Update SyncChainMmr endpoint upper bound logic

bin/stress-test/src/store/mod.rs

@@ -469,8 +469,8 @@ async fn sync_chain_mmr(
     block_to: u32,
 ) -> SyncChainMmrRun {
     let sync_request = proto::rpc::SyncChainMmrRequest {
-        block_range: Some(proto::rpc::BlockRange { block_from, block_to: Some(block_to) }),
-        finality: proto::rpc::Finality::Committed.into(),
+        block_from,
+        upper_bound: Some(proto::rpc::sync_chain_mmr_request::UpperBound::BlockNum(block_to)),
     };
 
     let start = Instant::now();

crates/proto/src/domain/block.rs

@@ -332,6 +332,42 @@ impl From<&FeeParameters> for proto::blockchain::FeeParameters {
     }
 }
 
+// SYNC TARGET
+// ================================================================================================
+
+/// The target block to sync up to in a chain MMR sync request.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum SyncTarget {
+    /// Sync up to a specific block number (inclusive).
+    BlockNumber(BlockNumber),
+    /// Sync up to the latest committed block (chain tip).
+    CommittedChainTip,
+    /// Sync up to the latest proven block.
+    ProvenChainTip,
+}
+
+impl TryFrom<proto::rpc::sync_chain_mmr_request::UpperBound> for SyncTarget {
+    type Error = ConversionError;
+
+    fn try_from(
+        value: proto::rpc::sync_chain_mmr_request::UpperBound,
+    ) -> Result<Self, Self::Error> {
+        use proto::rpc::sync_chain_mmr_request::UpperBound;
+
+        match value {
+            UpperBound::BlockNum(block_num) => Ok(Self::BlockNumber(block_num.into())),
+            UpperBound::ChainTip(tip) => match proto::rpc::ChainTip::try_from(tip) {
+                Ok(proto::rpc::ChainTip::Committed) => Ok(Self::CommittedChainTip),
+                Ok(proto::rpc::ChainTip::Proven) => Ok(Self::ProvenChainTip),
+                // These variants should never be encountered.
+                Ok(proto::rpc::ChainTip::Unspecified) | Err(_) => {
+                    Err(ConversionError::message("unexpected chain tip"))
+                },
+            },
+        }
+    }
+}
+
 // BLOCK RANGE
 // ================================================================================================
 

crates/rpc/src/tests.rs

@@ -607,8 +607,10 @@ async fn sync_chain_mmr_returns_delta() {
     let (store_runtime, _data_directory, _genesis, _store_addr) = start_store(store_listener).await;
 
     let request = proto::rpc::SyncChainMmrRequest {
-        block_range: Some(proto::rpc::BlockRange { block_from: 0, block_to: None }),
-        finality: proto::rpc::Finality::Committed.into(),
+        block_from: 0,
+        upper_bound: Some(proto::rpc::sync_chain_mmr_request::UpperBound::ChainTip(
+            proto::rpc::ChainTip::Committed.into(),
+        )),
     };
     let response = rpc_client.sync_chain_mmr(request).await.expect("sync_chain_mmr should succeed");
     let response = response.into_inner();

crates/store/src/server/rpc_api.rs

@@ -1,6 +1,5 @@
 use miden_node_proto::convert;
-use miden_node_proto::domain::block::InvalidBlockRange;
-use miden_node_proto::errors::ConversionError;
+use miden_node_proto::domain::block::SyncTarget;
 use miden_node_proto::generated::store::rpc_server;
 use miden_node_proto::generated::{self as proto};
 use miden_node_utils::limiter::{
@@ -169,37 +168,29 @@ impl rpc_server::Rpc for StoreApi {
         let request = request.into_inner();
         let chain_tip = self.state.latest_block_num().await;
 
-        let block_range = request
-            .block_range
-            .ok_or_else(|| {
-                ConversionError::missing_field::<proto::rpc::SyncChainMmrRequest>("block_range")
-            })
-            .map_err(SyncChainMmrError::DeserializationFailed)?;
+        let block_from = BlockNumber::from(request.block_from);
+
+        // Determine upper bound to sync to or default to last committed block.
+        let sync_target = request
+            .upper_bound
+            .map(SyncTarget::try_from)
+            .transpose()
+            .map_err(SyncChainMmrError::DeserializationFailed)?
+            .unwrap_or(SyncTarget::CommittedChainTip);
 
-        // Determine the effective tip based on the requested finality level.
-        let effective_tip = match request.finality() {
-            proto::rpc::Finality::Unspecified | proto::rpc::Finality::Committed => chain_tip,
-            proto::rpc::Finality::Proven => self
+        let block_to = match sync_target {
+            SyncTarget::BlockNumber(block_num) => block_num.min(chain_tip),
+            SyncTarget::CommittedChainTip => chain_tip,
+            SyncTarget::ProvenChainTip => self
                 .state
                 .db()
                 .select_latest_proven_in_sequence_block_num()
                 .await
                 .map_err(SyncChainMmrError::DatabaseError)?,
         };
 
-        let block_from = BlockNumber::from(block_range.block_from);
-        if block_from > effective_tip {
-            Err(SyncChainMmrError::FutureBlock { chain_tip: effective_tip, block_from })?;
-        }
-
-        let block_to =
-            block_range.block_to.map_or(effective_tip, BlockNumber::from).min(effective_tip);
-
         if block_from > block_to {
-            Err(SyncChainMmrError::InvalidBlockRange(InvalidBlockRange::StartGreaterThanEnd {
-                start: block_from,
-                end: block_to,
-            }))?;
+            Err(SyncChainMmrError::FutureBlock { chain_tip: block_to, block_from })?;
         }
         let block_range = block_from..=block_to;
         let mmr_delta =

proto/proto/rpc.proto

@@ -504,30 +504,30 @@ message SyncNotesResponse {
 // SYNC CHAIN MMR
 // ================================================================================================
 
-// The finality level for chain data queries.
-enum Finality {
-    // Return data up to the latest committed block.
-    FINALITY_UNSPECIFIED = 0;
-    // Return data up to the latest committed block.
-    FINALITY_COMMITTED = 1;
-    // Return data only up to the latest proven block.
-    FINALITY_PROVEN = 2;
+// The chain tip variant to sync up to.
+enum ChainTip {
+    CHAIN_TIP_UNSPECIFIED = 0;
+    // Sync up to the latest committed block (chain tip).
+    CHAIN_TIP_COMMITTED = 1;
+    // Sync up to the latest proven block.
+    CHAIN_TIP_PROVEN = 2;
 }
 
 // Chain MMR synchronization request.
 message SyncChainMmrRequest {
-    // Block range from which to synchronize the chain MMR.
-    //
-    // The response will contain MMR delta starting after `block_range.block_from` up to
-    // `block_range.block_to` or the effective tip (whichever is lower). Set `block_from` to the
-    // last block already present in the caller's MMR so the delta begins at the next block.
-    BlockRange block_range = 1;
+    // Block number from which to synchronize (inclusive). Set this to the last block
+    // already present in the caller's MMR so the delta begins at the next block.
+    fixed32 block_from = 1;
 
-    // The finality level to use when clamping the upper bound of the block range.
-    //
-    // When set to `FINALITY_UNSPECIFIED` or `FINALITY_COMMITTED`, the upper bound is clamped to the chain tip.
-    // When set to `FINALITY_PROVEN`, the upper bound is clamped to the latest proven block.
-    Finality finality = 2;
+    // Upper bound for the block range. Determines how far ahead to sync.
+    oneof upper_bound {
+        // Sync up to this specific block number (inclusive), clamped to the committed chain tip.
+        fixed32 block_num = 2;
+        // Sync up to a chain tip variant (committed or proven).
+        ChainTip chain_tip = 3;
+    }
+
+    reserved 4;
 }
 
 // Represents the result of syncing chain MMR.