feat: Add proof to GetBlockByNumber

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## v0.15.0 (TBD)
+
+- [BREAKING] Changed `GetBlockByNumber` to accept a `GetBlockByNumberRequest` (with optional `include_proof` flag) and returns a `GetBlockByNumberResponse` containing the block and an optional block proof ([#1864](https://github.com/0xMiden/node/pull/1864)).
+
 ## v0.14.0 (TBD)
 
 ### Enhancements

crates/rpc/src/server/api.rs

@@ -233,8 +233,8 @@ impl api_server::Api for RpcService {
 
     async fn get_block_by_number(
         &self,
-        request: Request<proto::blockchain::BlockNumber>,
-    ) -> Result<Response<proto::blockchain::MaybeBlock>, Status> {
+        request: Request<proto::blockchain::GetBlockByNumberRequest>,
+    ) -> Result<Response<proto::blockchain::GetBlockByNumberResponse>, Status> {
         let request = request.into_inner();
 
         debug!(target: COMPONENT, ?request);

crates/store/src/blocks.rs

@@ -1,3 +1,12 @@
+//! File-based storage for raw block data and block proofs.
+//!
+//! Block data is stored under `{store_dir}/{epoch:04x}/block_{block_num:08x}.dat`, and proof data
+//! for proven blocks is stored under `{store_dir}/{epoch:04x}/proof_{block_num:08x}.dat`.
+//!
+//! The epoch is derived from the 16 most significant bits of the block number (i.e.,
+//! `block_num >> 16`), and both the epoch and block number are formatted as zero-padded
+//! hexadecimal strings.
+
 use std::io::ErrorKind;
 use std::ops::Not;
 use std::path::PathBuf;
@@ -96,6 +105,14 @@ impl BlockStore {
         fs_err::write(block_path, data)
     }
 
+    pub async fn load_proof(&self, block_num: BlockNumber) -> std::io::Result<Option<Vec<u8>>> {
+        match tokio::fs::read(self.proof_path(block_num)).await {
+            Ok(data) => Ok(Some(data)),
+            Err(err) if err.kind() == std::io::ErrorKind::NotFound => Ok(None),
+            Err(err) => Err(err),
+        }
+    }
+
     // PROOF STORAGE
     // --------------------------------------------------------------------------------------------
 

crates/store/src/server/rpc_api.rs

@@ -237,19 +237,24 @@ impl rpc_server::Rpc for StoreApi {
 
     async fn get_block_by_number(
         &self,
-        request: Request<proto::blockchain::BlockNumber>,
-    ) -> Result<Response<proto::blockchain::MaybeBlock>, Status> {
+        request: Request<proto::blockchain::GetBlockByNumberRequest>,
+    ) -> Result<Response<proto::blockchain::GetBlockByNumberResponse>, Status> {
         let request = request.into_inner();
 
         debug!(target: COMPONENT, ?request);
 
-        let block = self
-            .state
-            .load_block(request.block_num.into())
-            .await
-            .map_err(GetBlockByNumberError::from)?;
+        // Load block from state.
+        let block_num = BlockNumber::from(request.block_num);
+        let block = self.state.load_block(block_num).await.map_err(GetBlockByNumberError::from)?;
+
+        // Load proof from state.
+        let proof = if request.include_proof.unwrap_or_default() {
+            self.state.load_proof(block_num).await.map_err(GetBlockByNumberError::from)?
+        } else {
+            None
+        };
 
-        Ok(Response::new(proto::blockchain::MaybeBlock { block }))
+        Ok(Response::new(proto::blockchain::GetBlockByNumberResponse { block, proof }))
     }
 
     async fn get_account(

crates/store/src/state/mod.rs

@@ -842,6 +842,17 @@ impl State {
         self.block_store.load_block(block_num).await.map_err(Into::into)
     }
 
+    /// Loads a block proof from the block store. Returns `Ok(None)` if the proof is not found.
+    pub async fn load_proof(
+        &self,
+        block_num: BlockNumber,
+    ) -> Result<Option<Vec<u8>>, DatabaseError> {
+        if block_num > self.latest_block_num().await {
+            return Ok(None);
+        }
+        self.block_store.load_proof(block_num).await.map_err(Into::into)
+    }
+
     /// Returns the latest block number.
     pub async fn latest_block_num(&self) -> BlockNumber {
         self.inner.read().await.latest_block_num()

proto/proto/internal/store.proto

@@ -34,8 +34,8 @@ service Rpc {
     // Returns the latest details the specified account.
     rpc GetAccount(rpc.AccountRequest) returns (rpc.AccountResponse) {}
 
-    // Returns raw block data for the specified block number.
-    rpc GetBlockByNumber(blockchain.BlockNumber) returns (blockchain.MaybeBlock) {}
+    // Returns raw block data for the specified block number, optionally including the block proof.
+    rpc GetBlockByNumber(blockchain.GetBlockByNumberRequest) returns (blockchain.GetBlockByNumberResponse) {}
 
     // Retrieves block header by given block number. Optionally, it also returns the MMR path
     // and current chain length to authenticate the block's inclusion.

proto/proto/rpc.proto

@@ -40,8 +40,8 @@ service Api {
     // Returns the latest details of the specified account.
     rpc GetAccount(AccountRequest) returns (AccountResponse) {}
 
-    // Returns raw block data for the specified block number.
-    rpc GetBlockByNumber(blockchain.BlockNumber) returns (blockchain.MaybeBlock) {}
+    // Returns raw block data for the specified block number, optionally including the block proof.
+    rpc GetBlockByNumber(blockchain.GetBlockByNumberRequest) returns (blockchain.GetBlockByNumberResponse) {}
 
     // Retrieves block header by given block number. Optionally, it also returns the MMR path
     // and current chain length to authenticate the block's inclusion.

proto/proto/types/blockchain.proto

@@ -28,6 +28,24 @@ message MaybeBlock {
     optional bytes block = 1;
 }
 
+// Request for retrieving a block by its number, optionally including the block proof.
+message GetBlockByNumberRequest {
+    // The block number of the target block.
+    fixed32 block_num = 1;
+    // Whether to include the block proof in the response.
+    optional bool include_proof = 2;
+}
+
+// Response containing the block data and optionally its proof.
+message GetBlockByNumberResponse {
+    // The requested block data encoded using [miden_serde_utils::Serializable] implementation for
+    // [miden_protocol::block::Block].
+    optional bytes block = 1;
+    // The block proof encoded using [miden_serde_utils::Serializable] implementation for
+    // [miden_protocol::block::BlockProof], if requested and available.
+    optional bytes proof = 2;
+}
+
 // Represents a block number.
 message BlockNumber {
     // The block number of the target block.