feat(rpc): fill size field in getblock with verbosity=2

zebra-rpc/src/methods.rs

@@ -172,12 +172,7 @@ pub trait Rpc {
     ///
     /// # Notes
     ///
-    /// Zebra previously partially supported verbosity=1 by returning only the
-    /// fields required by lightwalletd ([`lightwalletd` only reads the `tx`
-    /// field of the result](https://github.com/zcash/lightwalletd/blob/dfac02093d85fb31fb9a8475b884dd6abca966c7/common/common.go#L152)).
-    /// That verbosity level was migrated to "3"; so while lightwalletd will
-    /// still work by using verbosity=1, it will sync faster if it is changed to
-    /// use verbosity=3.
+    /// The `size` field is only returned with verbosity=2.
     ///
     /// The undocumented `chainwork` field is not returned.
     #[method(name = "getblock")]
@@ -887,7 +882,7 @@ where
 
             let transactions_request = match verbosity {
                 1 => zebra_state::ReadRequest::TransactionIdsForBlock(hash_or_height),
-                2 => zebra_state::ReadRequest::Block(hash_or_height),
+                2 => zebra_state::ReadRequest::BlockAndSize(hash_or_height),
                 _other => panic!("get_block_header_fut should be none"),
             };
 
@@ -916,28 +911,34 @@ where
             }
 
             let tx_ids_response = futs.next().await.expect("`futs` should not be empty");
-            let tx: Vec<_> = match tx_ids_response.map_misc_error()? {
-                zebra_state::ReadResponse::TransactionIdsForBlock(tx_ids) => tx_ids
-                    .ok_or_misc_error("block not found")?
-                    .iter()
-                    .map(|tx_id| GetBlockTransaction::Hash(*tx_id))
-                    .collect(),
-                zebra_state::ReadResponse::Block(block) => block
-                    .ok_or_misc_error("Block not found")?
-                    .transactions
-                    .iter()
-                    .map(|tx| {
-                        GetBlockTransaction::Object(TransactionObject::from_transaction(
-                            tx.clone(),
-                            Some(height),
-                            Some(
-                                confirmations
-                                    .try_into()
-                                    .expect("should be less than max block height, i32::MAX"),
-                            ),
-                        ))
-                    })
-                    .collect(),
+            let (tx, size): (Vec<_>, Option<usize>) = match tx_ids_response.map_misc_error()? {
+                zebra_state::ReadResponse::TransactionIdsForBlock(tx_ids) => (
+                    tx_ids
+                        .ok_or_misc_error("block not found")?
+                        .iter()
+                        .map(|tx_id| GetBlockTransaction::Hash(*tx_id))
+                        .collect(),
+                    None,
+                ),
+                zebra_state::ReadResponse::BlockAndSize(block_and_size) => {
+                    let (block, size) = block_and_size.ok_or_misc_error("Block not found")?;
+                    let transactions = block
+                        .transactions
+                        .iter()
+                        .map(|tx| {
+                            GetBlockTransaction::Object(TransactionObject::from_transaction(
+                                tx.clone(),
+                                Some(height),
+                                Some(
+                                    confirmations
+                                        .try_into()
+                                        .expect("should be less than max block height, i32::MAX"),
+                                ),
+                            ))
+                        })
+                        .collect();
+                    (transactions, Some(size))
+                }
                 _ => unreachable!("unmatched response to a transaction_ids_for_block request"),
             };
 
@@ -984,7 +985,7 @@ where
                 difficulty: Some(difficulty),
                 tx,
                 trees,
-                size: None,
+                size: size.map(|size| size as i64),
                 block_commitments: Some(block_commitments),
                 final_sapling_root: Some(final_sapling_root),
                 final_orchard_root,

zebra-rpc/src/methods/tests/snapshots/get_block_verbose_hash_verbosity_2@mainnet_10.snap

@@ -5,6 +5,7 @@ expression: block
 {
   "hash": "0007bc227e1c57a4a70e237cad00e7b7ce565155ab49166bc57397a26d339283",
   "confirmations": 10,
+  "size": 1617,
   "height": 1,
   "version": 4,
   "merkleroot": "851bf6fbf7a976327817c738c489d7fa657752445430922d94c983c0b9ed4609",

zebra-rpc/src/methods/tests/snapshots/get_block_verbose_hash_verbosity_2@testnet_10.snap

@@ -5,6 +5,7 @@ expression: block
 {
   "hash": "025579869bcf52a989337342f5f57a84f3a28b968f7d6a8307902b065a668d23",
   "confirmations": 10,
+  "size": 1618,
   "height": 1,
   "version": 4,
   "merkleroot": "f37e9f691fffb635de0999491d906ee85ba40cd36dae9f6e5911a8277d7c5f75",

zebra-rpc/src/methods/tests/snapshots/get_block_verbose_height_verbosity_2@mainnet_10.snap

@@ -5,6 +5,7 @@ expression: block
 {
   "hash": "0007bc227e1c57a4a70e237cad00e7b7ce565155ab49166bc57397a26d339283",
   "confirmations": 10,
+  "size": 1617,
   "height": 1,
   "version": 4,
   "merkleroot": "851bf6fbf7a976327817c738c489d7fa657752445430922d94c983c0b9ed4609",

zebra-rpc/src/methods/tests/snapshots/get_block_verbose_height_verbosity_2@testnet_10.snap

@@ -5,6 +5,7 @@ expression: block
 {
   "hash": "025579869bcf52a989337342f5f57a84f3a28b968f7d6a8307902b065a668d23",
   "confirmations": 10,
+  "size": 1618,
   "height": 1,
   "version": 4,
   "merkleroot": "f37e9f691fffb635de0999491d906ee85ba40cd36dae9f6e5911a8277d7c5f75",

zebra-rpc/src/methods/tests/vectors.rs

@@ -316,7 +316,7 @@ async fn rpc_getblock() {
                     }))
                     .collect(),
                 trees,
-                size: None,
+                size: Some(block.zcash_serialize_to_vec().unwrap().len() as i64),
                 version: Some(block.header.version),
                 merkle_root: Some(block.header.merkle_root),
                 block_commitments: Some(expected_block_commitments),
@@ -364,7 +364,7 @@ async fn rpc_getblock() {
                     }))
                     .collect(),
                 trees,
-                size: None,
+                size: Some(block.zcash_serialize_to_vec().unwrap().len() as i64),
                 version: Some(block.header.version),
                 merkle_root: Some(block.header.merkle_root),
                 block_commitments: Some(expected_block_commitments),

zebra-state/src/lib.rs

@@ -51,7 +51,9 @@ pub use request::Spend;
 pub use response::{GetBlockTemplateChainInfo, KnownBlock, MinedTx, ReadResponse, Response};
 pub use service::{
     chain_tip::{ChainTipBlock, ChainTipChange, ChainTipSender, LatestChainTip, TipAction},
-    check, init, init_read_only,
+    check,
+    finalized_state::FinalizedState,
+    init, init_read_only,
     non_finalized_state::NonFinalizedState,
     spawn_init, spawn_init_read_only,
     watch_receiver::WatchReceiver,

zebra-state/src/request.rs

@@ -715,6 +715,14 @@ pub enum Request {
     /// [`block::Height`] using `.into()`.
     Block(HashOrHeight),
 
+    //// Same as Block, but also returns serialized block size.
+    ////
+    /// Returns
+    ///
+    /// * [`ReadResponse::BlockAndSize(Some((Arc<Block>, usize)))`](ReadResponse::BlockAndSize) if the block is in the best chain;
+    /// * [`ReadResponse::BlockAndSize(None)`](ReadResponse::BlockAndSize) otherwise.
+    BlockAndSize(HashOrHeight),
+
     /// Looks up a block header by hash or height in the current best chain.
     ///
     /// Returns
@@ -837,6 +845,7 @@ impl Request {
             Request::Transaction(_) => "transaction",
             Request::UnspentBestChainUtxo { .. } => "unspent_best_chain_utxo",
             Request::Block(_) => "block",
+            Request::BlockAndSize(_) => "block_and_size",
             Request::BlockHeader(_) => "block_header",
             Request::FindBlockHashes { .. } => "find_block_hashes",
             Request::FindBlockHeaders { .. } => "find_block_headers",
@@ -897,6 +906,14 @@ pub enum ReadRequest {
     /// [`block::Height`] using `.into()`.
     Block(HashOrHeight),
 
+    //// Same as Block, but also returns serialized block size.
+    ////
+    /// Returns
+    ///
+    /// * [`ReadResponse::BlockAndSize(Some((Arc<Block>, usize)))`](ReadResponse::BlockAndSize) if the block is in the best chain;
+    /// * [`ReadResponse::BlockAndSize(None)`](ReadResponse::BlockAndSize) otherwise.
+    BlockAndSize(HashOrHeight),
+
     /// Looks up a block header by hash or height in the current best chain.
     ///
     /// Returns
@@ -1143,6 +1160,7 @@ impl ReadRequest {
             ReadRequest::TipPoolValues => "tip_pool_values",
             ReadRequest::Depth(_) => "depth",
             ReadRequest::Block(_) => "block",
+            ReadRequest::BlockAndSize(_) => "block_and_size",
             ReadRequest::BlockHeader(_) => "block_header",
             ReadRequest::Transaction(_) => "transaction",
             ReadRequest::TransactionIdsForBlock(_) => "transaction_ids_for_block",
@@ -1200,6 +1218,7 @@ impl TryFrom<Request> for ReadRequest {
             Request::BestChainBlockHash(hash) => Ok(ReadRequest::BestChainBlockHash(hash)),
 
             Request::Block(hash_or_height) => Ok(ReadRequest::Block(hash_or_height)),
+            Request::BlockAndSize(hash_or_height) => Ok(ReadRequest::BlockAndSize(hash_or_height)),
             Request::BlockHeader(hash_or_height) => Ok(ReadRequest::BlockHeader(hash_or_height)),
             Request::Transaction(tx_hash) => Ok(ReadRequest::Transaction(tx_hash)),
             Request::UnspentBestChainUtxo(outpoint) => {

zebra-state/src/response.rs

@@ -50,6 +50,9 @@ pub enum Response {
     /// Response to [`Request::Block`] with the specified block.
     Block(Option<Arc<Block>>),
 
+    /// Response to [`Request::BlockAndSize`] with the specified block and size.
+    BlockAndSize(Option<(Arc<Block>, usize)>),
+
     /// The response to a `BlockHeader` request.
     BlockHeader {
         /// The header of the requested block
@@ -157,6 +160,10 @@ pub enum ReadResponse {
     /// Response to [`ReadRequest::Block`] with the specified block.
     Block(Option<Arc<Block>>),
 
+    /// Response to [`ReadRequest::BlockAndSize`] with the specified block and
+    /// serialized size.
+    BlockAndSize(Option<(Arc<Block>, usize)>),
+
     /// The response to a `BlockHeader` request.
     BlockHeader {
         /// The header of the requested block
@@ -311,6 +318,7 @@ impl TryFrom<ReadResponse> for Response {
             ReadResponse::BlockHash(hash) => Ok(Response::BlockHash(hash)),
 
             ReadResponse::Block(block) => Ok(Response::Block(block)),
+            ReadResponse::BlockAndSize(block) => Ok(Response::BlockAndSize(block)),
             ReadResponse::BlockHeader {
                 header,
                 hash,

zebra-state/src/service.rs

@@ -1092,6 +1092,7 @@ impl Service<Request> for StateService {
             | Request::Transaction(_)
             | Request::UnspentBestChainUtxo(_)
             | Request::Block(_)
+            | Request::BlockAndSize(_)
             | Request::BlockHeader(_)
             | Request::FindBlockHashes { .. }
             | Request::FindBlockHeaders { .. }
@@ -1311,6 +1312,31 @@ impl Service<ReadRequest> for ReadStateService {
                 .wait_for_panics()
             }
 
+            // Used by the get_block (raw) RPC and the StateService.
+            ReadRequest::BlockAndSize(hash_or_height) => {
+                let state = self.clone();
+
+                tokio::task::spawn_blocking(move || {
+                    span.in_scope(move || {
+                        let block_and_size = state.non_finalized_state_receiver.with_watch_data(
+                            |non_finalized_state| {
+                                read::block_and_size(
+                                    non_finalized_state.best_chain(),
+                                    &state.db,
+                                    hash_or_height,
+                                )
+                            },
+                        );
+
+                        // The work is done in the future.
+                        timer.finish(module_path!(), line!(), "ReadRequest::BlockAndSize");
+
+                        Ok(ReadResponse::BlockAndSize(block_and_size))
+                    })
+                })
+                .wait_for_panics()
+            }
+
             // Used by the get_block (verbose) RPC and the StateService.
             ReadRequest::BlockHeader(hash_or_height) => {
                 let state = self.clone();