feat: Return code for FPI

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## v0.6.0 (TBD)
 
+- Added `AccountCode` as part of `GetAccountProofs` endpoint response (#521).
 - [BREAKING] Added `kernel_root` to block header's protobuf message definitions (#496).
 - [BREAKING] Renamed `off-chain` and `on-chain` to `private` and `public` respectively for the account storage modes (#489).
 - Optimized state synchronizations by removing unnecessary fetching and parsing of note details (#462).

crates/proto/src/generated/requests.rs

@@ -153,7 +153,11 @@ pub struct GetAccountProofsRequest {
     /// List of account IDs to get states.
     #[prost(message, repeated, tag = "1")]
     pub account_ids: ::prost::alloc::vec::Vec<super::account::AccountId>,
+    /// Account code commitments corresponding to the last-known `AccountCode` for requested
+    /// accounts. Responses will include only the ones that are not known to the caller.
+    #[prost(message, repeated, tag = "2")]
+    pub code_commitments: ::prost::alloc::vec::Vec<super::digest::Digest>,
     /// Optional flag to include header in the response. `false` by default.
-    #[prost(bool, optional, tag = "2")]
+    #[prost(bool, optional, tag = "3")]
     pub include_headers: ::core::option::Option<bool>,
 }

crates/proto/src/generated/responses.rs

@@ -215,8 +215,12 @@ pub struct AccountProofsResponse {
     /// Authentication path from the `account_root` of the block header to the account.
     #[prost(message, optional, tag = "3")]
     pub account_proof: ::core::option::Option<super::merkle::MerklePath>,
+    /// Account code, returned only in the case where the request code commitment does not match
+    /// with the current one.
+    #[prost(bytes = "vec", optional, tag = "4")]
+    pub account_code: ::core::option::Option<::prost::alloc::vec::Vec<u8>>,
     /// State header for public accounts. Filled only if `include_headers` flag is set to `true`.
-    #[prost(message, optional, tag = "4")]
+    #[prost(message, optional, tag = "5")]
     pub state_header: ::core::option::Option<AccountStateHeader>,
 }
 #[derive(Clone, PartialEq, ::prost::Message)]

crates/rpc-proto/proto/requests.proto

@@ -135,6 +135,9 @@ message GetAccountStateDeltaRequest {
 message GetAccountProofsRequest {
     // List of account IDs to get states.
     repeated account.AccountId account_ids = 1;
+    // Account code commitments corresponding to the last-known `AccountCode` for requested 
+    // accounts. Responses will include only the ones that are not known to the caller.
+    repeated digest.Digest code_commitments = 2;
     // Optional flag to include header in the response. `false` by default.
-    optional bool include_headers = 2;
+    optional bool include_headers = 3;
 }

crates/rpc-proto/proto/responses.proto

@@ -188,8 +188,11 @@ message AccountProofsResponse {
     digest.Digest account_hash = 2;
     // Authentication path from the `account_root` of the block header to the account.
     merkle.MerklePath account_proof = 3;
+    // Account code, returned only in the case where the request code commitment does not match
+    // with the current one.
+    optional bytes account_code = 4;
     // State header for public accounts. Filled only if `include_headers` flag is set to `true`.
-    optional AccountStateHeader state_header = 4;
+    optional AccountStateHeader state_header = 5;
 }
 
 message AccountStateHeader {

crates/store/src/server/api.rs

@@ -490,8 +490,12 @@ impl api_server::Api for StoreApi {
 
         let account_ids = convert(request.account_ids);
         let include_headers = request.include_headers.unwrap_or_default();
-        let (block_num, infos) =
-            self.state.get_account_proofs(account_ids, include_headers).await?;
+        let request_code_commitments = try_convert(request.code_commitments)
+            .map_err(|err| Status::invalid_argument(format!("Invalid code commitment: {}", err)))?;
+        let (block_num, infos) = self
+            .state
+            .get_account_proofs(account_ids, request_code_commitments, include_headers)
+            .await?;
 
         Ok(Response::new(GetAccountProofsResponse {
             block_num,

crates/store/src/state.rs

@@ -5,6 +5,7 @@
 
 use std::{
     collections::{BTreeMap, BTreeSet},
+    ops::Not,
     sync::Arc,
 };
 
@@ -16,7 +17,7 @@ use miden_node_proto::{
 };
 use miden_node_utils::formatting::{format_account_id, format_array};
 use miden_objects::{
-    accounts::{AccountDelta, AccountHeader},
+    accounts::{AccountCode, AccountDelta, AccountHeader},
     block::Block,
     crypto::{
         hash::rpo::RpoDigest,
@@ -683,16 +684,15 @@ impl State {
     pub async fn get_account_proofs(
         &self,
         account_ids: Vec<AccountId>,
+        request_code_commitments: Vec<RpoDigest>,
         include_headers: bool,
     ) -> Result<(BlockNumber, Vec<AccountProofsResponse>), DatabaseError> {
         // Lock inner state for the whole operation. We need to hold this lock to prevent the
         // database, account tree and latest block number from changing during the operation,
         // because changing one of them would lead to inconsistent state.
         let inner_state = self.inner.read().await;
 
-        let state_headers = if !include_headers {
-            BTreeMap::<AccountId, AccountStateHeader>::default()
-        } else {
+        let account_data: BTreeMap<u64, (AccountStateHeader, AccountCode)> = {
             let infos = self.db.select_accounts_by_ids(account_ids.clone()).await?;
 
             if account_ids.len() > infos.len() {
@@ -709,10 +709,13 @@ impl State {
                     info.details.map(|details| {
                         (
                             info.summary.account_id.into(),
-                            AccountStateHeader {
-                                header: Some(AccountHeader::from(&details).into()),
-                                storage_header: details.storage().get_header().to_bytes(),
-                            },
+                            (
+                                AccountStateHeader {
+                                    header: Some(AccountHeader::from(&details).into()),
+                                    storage_header: details.storage().get_header().to_bytes(),
+                                },
+                                details.code().clone(),
+                            ),
                         )
                     })
                 })
@@ -724,12 +727,21 @@ impl State {
             .map(|account_id| {
                 let acc_leaf_idx = LeafIndex::new_max_depth(account_id);
                 let opening = inner_state.account_tree.open(&acc_leaf_idx);
+                let (state_header, account_code) = account_data
+                    .get(&account_id)
+                    .cloned()
+                    .expect("Function would have errored if accounts were not found");
+                let account_code = request_code_commitments
+                    .contains(&account_code.commitment())
+                    .not()
+                    .then_some(account_code.to_bytes());
 
                 AccountProofsResponse {
                     account_id: Some(account_id.into()),
                     account_hash: Some(opening.value.into()),
                     account_proof: Some(opening.path.into()),
-                    state_header: state_headers.get(&account_id).cloned(),
+                    account_code,
+                    state_header: include_headers.then_some(state_header),
                 }
             })
             .collect();

proto/requests.proto

@@ -135,6 +135,9 @@ message GetAccountStateDeltaRequest {
 message GetAccountProofsRequest {
     // List of account IDs to get states.
     repeated account.AccountId account_ids = 1;
+    // Account code commitments corresponding to the last-known `AccountCode` for requested 
+    // accounts. Responses will include only the ones that are not known to the caller.
+    repeated digest.Digest code_commitments = 2;
     // Optional flag to include header in the response. `false` by default.
-    optional bool include_headers = 2;
+    optional bool include_headers = 3;
 }

proto/responses.proto

@@ -188,8 +188,11 @@ message AccountProofsResponse {
     digest.Digest account_hash = 2;
     // Authentication path from the `account_root` of the block header to the account.
     merkle.MerklePath account_proof = 3;
+    // Account code, returned only in the case where the request code commitment does not match
+    // with the current one.
+    optional bytes account_code = 4;
     // State header for public accounts. Filled only if `include_headers` flag is set to `true`.
-    optional AccountStateHeader state_header = 4;
+    optional AccountStateHeader state_header = 5;
 }
 
 message AccountStateHeader {