Restore GetNodeData (#469)

* Accept GetNodeData requests

* Implement blockchain client method for node data requests

* Reuse old database read methods for node data

* fmt

* Copy & paste old tests...

* ... and make them work

* fmt

crates/db/journaldb/src/archivedb.rs

@@ -25,12 +25,14 @@ use std::{
 use super::{
     error_key_already_exists, error_negatively_reference_hash, memory_db::*, LATEST_ERA_KEY,
 };
+use bytes::Bytes;
 use ethcore_db::{DBTransaction, DBValue, KeyValueDB};
 use ethereum_types::H256;
 use hash_db::HashDB;
 use keccak_hasher::KeccakHasher;
 use rlp::{decode, encode};
 use traits::JournalDB;
+use DB_PREFIX_LEN;
 
 /// Implementation of the `HashDB` trait for a disk-backed database with a memory overlay
 /// and latent-removal semantics.
@@ -214,12 +216,19 @@ impl JournalDB for ArchiveDB {
     fn consolidate(&mut self, with: MemoryDB<KeccakHasher, DBValue>) {
         self.overlay.consolidate(with);
     }
+
+    fn state(&self, id: &H256) -> Option<Bytes> {
+        self.backing
+            .get_by_prefix(self.column, &id[0..DB_PREFIX_LEN])
+            .map(|b| b.into_vec())
+    }
 }
 
 #[cfg(test)]
 mod tests {
 
     use super::*;
+    use ethcore_db::InMemoryWithMetrics;
     use hash_db::HashDB;
     use keccak::keccak;
     use JournalDB;
@@ -497,4 +506,22 @@ mod tests {
 
         assert!(jdb.get(&key).is_none());
     }
+
+    #[test]
+    fn returns_state() {
+        let shared_db = Arc::new(InMemoryWithMetrics::create(0));
+
+        let key = {
+            let mut jdb = ArchiveDB::new(shared_db.clone(), None);
+            let key = jdb.insert(b"foo");
+            jdb.commit_batch(0, &keccak(b"0"), None).unwrap();
+            key
+        };
+
+        {
+            let jdb = ArchiveDB::new(shared_db, None);
+            let state = jdb.state(&key);
+            assert!(state.is_some());
+        }
+    }
 }

crates/db/journaldb/src/earlymergedb.rs

@@ -35,6 +35,7 @@ use parity_util_mem::MallocSizeOf;
 use parking_lot::RwLock;
 use rlp::{decode, encode};
 use util::{DatabaseKey, DatabaseValueRef, DatabaseValueView};
+use DB_PREFIX_LEN;
 
 #[derive(Debug, Clone, PartialEq, Eq, MallocSizeOf)]
 struct RefInfo {
@@ -608,6 +609,12 @@ impl JournalDB for EarlyMergeDB {
     fn consolidate(&mut self, with: MemoryDB<KeccakHasher, DBValue>) {
         self.overlay.consolidate(with);
     }
+
+    fn state(&self, id: &H256) -> Option<Bytes> {
+        self.backing
+            .get_by_prefix(self.column, &id[0..DB_PREFIX_LEN])
+            .map(|b| b.into_vec())
+    }
 }
 
 #[cfg(test)]

crates/db/journaldb/src/overlayrecentdb.rs

@@ -23,6 +23,7 @@ use std::{
 };
 
 use super::{error_negatively_reference_hash, JournalDB, DB_PREFIX_LEN, LATEST_ERA_KEY};
+use bytes::Bytes;
 use ethcore_db::{DBTransaction, DBValue, KeyValueDB};
 use ethereum_types::H256;
 use fastmap::H256FastMap;
@@ -509,6 +510,26 @@ impl JournalDB for OverlayRecentDB {
     fn consolidate(&mut self, with: MemoryDB<KeccakHasher, DBValue>) {
         self.transaction_overlay.consolidate(with);
     }
+
+    fn state(&self, key: &H256) -> Option<Bytes> {
+        let journal_overlay = self.journal_overlay.read();
+        let key = to_short_key(key);
+        journal_overlay
+            .backing_overlay
+            .get(&key)
+            .map(|v| v.into_vec())
+            .or_else(|| {
+                journal_overlay
+                    .pending_overlay
+                    .get(&key)
+                    .map(|d| d.clone().into_vec())
+            })
+            .or_else(|| {
+                self.backing
+                    .get_by_prefix(self.column, &key[0..DB_PREFIX_LEN])
+                    .map(|b| b.into_vec())
+            })
+    }
 }
 
 impl HashDB<KeccakHasher, DBValue> for OverlayRecentDB {

crates/db/journaldb/src/refcounteddb.rs

@@ -23,6 +23,7 @@ use std::{
 };
 
 use super::{traits::JournalDB, LATEST_ERA_KEY};
+use bytes::Bytes;
 use ethcore_db::{DBTransaction, DBValue, KeyValueDB};
 use ethereum_types::H256;
 use hash_db::HashDB;
@@ -32,6 +33,7 @@ use overlaydb::OverlayDB;
 use parity_util_mem::{allocators::new_malloc_size_ops, MallocSizeOf};
 use rlp::{decode, encode};
 use util::{DatabaseKey, DatabaseValueRef, DatabaseValueView};
+use DB_PREFIX_LEN;
 
 /// Implementation of the `HashDB` trait for a disk-backed database with a memory overlay
 /// and latent-removal semantics.
@@ -245,6 +247,12 @@ impl JournalDB for RefCountedDB {
             }
         }
     }
+
+    fn state(&self, id: &H256) -> Option<Bytes> {
+        self.backing
+            .get_by_prefix(self.column, &id[0..DB_PREFIX_LEN])
+            .map(|b| b.into_vec())
+    }
 }
 
 #[cfg(test)]

crates/db/journaldb/src/traits.rs

@@ -18,6 +18,7 @@
 
 use std::{io, sync::Arc};
 
+use bytes::Bytes;
 use ethcore_db::{DBTransaction, DBValue, KeyValueDB};
 use ethereum_types::H256;
 use hash_db::{AsHashDB, HashDB};
@@ -95,6 +96,9 @@ pub trait JournalDB: KeyedHashDB {
     /// Consolidate all the insertions and deletions in the given memory overlay.
     fn consolidate(&mut self, overlay: ::memory_db::MemoryDB<KeccakHasher, DBValue>);
 
+    /// State data query
+    fn state(&self, id: &H256) -> Option<Bytes>;
+
     /// Commit all changes in a single batch
     #[cfg(test)]
     fn commit_batch(&mut self, now: u64, id: &H256, end: Option<(u64, H256)>) -> io::Result<u32> {

crates/ethcore/src/client/client.rs

@@ -2776,6 +2776,10 @@ impl BlockChainClient for Client {
     fn registrar_address(&self) -> Option<Address> {
         self.registrar_address.clone()
     }
+
+    fn state_data(&self, hash: &H256) -> Option<Bytes> {
+        self.state_db.read().journal_db().state(hash)
+    }
 }
 
 impl IoClient for Client {

crates/ethcore/src/client/test_client.rs

@@ -1078,6 +1078,18 @@ impl BlockChainClient for TestBlockChainClient {
     fn registrar_address(&self) -> Option<Address> {
         None
     }
+
+    fn state_data(&self, hash: &H256) -> Option<Bytes> {
+        let begins_with_f =
+            H256::from_str("f000000000000000000000000000000000000000000000000000000000000000")
+                .unwrap();
+        if *hash > begins_with_f {
+            let mut rlp = RlpStream::new();
+            rlp.append(&hash.clone());
+            return Some(rlp.out());
+        }
+        None
+    }
 }
 
 impl IoClient for TestBlockChainClient {

crates/ethcore/src/client/traits.rs

@@ -333,6 +333,9 @@ pub trait BlockChainClient:
     /// Get all possible uncle hashes for a block.
     fn find_uncles(&self, hash: &H256) -> Option<Vec<H256>>;
 
+    /// Get latest state node
+    fn state_data(&self, hash: &H256) -> Option<Bytes>;
+
     /// Get block receipts data by block header hash.
     fn block_receipts(&self, hash: &H256) -> Option<BlockReceipts>;
 

crates/ethcore/src/tests/client.rs

@@ -591,3 +591,12 @@ fn import_export_binary() {
     assert!(client.block_header(BlockId::Number(17)).is_some());
     assert!(client.block_header(BlockId::Number(16)).is_some());
 }
+
+#[test]
+fn returns_state_root_basic() {
+    let client = generate_dummy_client(6);
+    let test_spec = Spec::new_test();
+    let genesis_header = test_spec.genesis_header();
+
+    assert!(client.state_data(genesis_header.state_root()).is_some());
+}

crates/ethcore/sync/src/chain/mod.rs

@@ -169,6 +169,7 @@ pub const PAR_PROTOCOL_VERSION_2: (u8, u8) = (2, 0x16);
 
 pub const MAX_BODIES_TO_SEND: usize = 256;
 pub const MAX_HEADERS_TO_SEND: usize = 512;
+pub const MAX_NODE_DATA_TO_SEND: usize = 1024;
 pub const MAX_RECEIPTS_HEADERS_TO_SEND: usize = 256;
 pub const MAX_TRANSACTIONS_TO_REQUEST: usize = 256;
 const MIN_PEERS_PROPAGATION: usize = 4;

crates/ethcore/sync/src/chain/supplier.rs

@@ -40,6 +40,7 @@ use super::{
     ChainSync, PacketProcessError, RlpResponseResult, SyncHandler, MAX_BODIES_TO_SEND,
     MAX_HEADERS_TO_SEND, MAX_RECEIPTS_HEADERS_TO_SEND,
 };
+use chain::MAX_NODE_DATA_TO_SEND;
 use std::borrow::Borrow;
 
 /// The Chain Sync Supplier: answers requests from peers with available data
@@ -88,6 +89,15 @@ impl SyncSupplier {
                         |e| format!("Error sending block headers: {:?}", e),
                     ),
 
+                    GetNodeDataPacket => SyncSupplier::return_rlp(
+                        io,
+                        &rlp,
+                        peer,
+                        request_id,
+                        SyncSupplier::return_node_data,
+                        |e| format!("Error sending node data: {:?}", e),
+                    ),
+
                     GetReceiptsPacket => SyncSupplier::return_rlp(
                         io,
                         &rlp,
@@ -340,6 +350,32 @@ impl SyncSupplier {
         Ok(Some((BlockBodiesPacket, rlp)))
     }
 
+    fn return_node_data(io: &dyn SyncIo, rlp: &Rlp, peer_id: PeerId) -> RlpResponseResult {
+        let count = cmp::min(rlp.item_count().unwrap_or(0), MAX_NODE_DATA_TO_SEND);
+        if count == 0 {
+            debug!(target: "sync", "Empty GetNodeData request, ignoring.");
+            return Ok(None);
+        }
+
+        let mut data = Bytes::new();
+
+        let mut added = 0usize;
+        for i in 0..count {
+            if let Some(ref mut node_data) = io.chain().state_data(&rlp.val_at::<H256>(i)?) {
+                data.append(node_data);
+                added += 1;
+                if data.len() > PAYLOAD_SOFT_LIMIT {
+                    break;
+                }
+            }
+        }
+
+        let mut rlp = RlpStream::new_list(added);
+        rlp.append_raw(&data, added);
+        trace!(target: "sync", "{} -> GetNodeData: returned {} entries", peer_id, added);
+        Ok(Some((NodeDataPacket, rlp)))
+    }
+
     fn return_receipts(io: &dyn SyncIo, rlp: &Rlp, peer_id: PeerId) -> RlpResponseResult {
         let mut count = rlp.item_count().unwrap_or(0);
         trace!(target: "sync", "{} -> GetReceipts: {} entries", peer_id, count);
@@ -723,4 +759,51 @@ mod test {
         );
         assert_eq!(1, io.packets.len());
     }
+
+    #[test]
+    fn return_nodes() {
+        let mut client = TestBlockChainClient::new();
+        let queue = RwLock::new(VecDeque::new());
+        let sync = dummy_sync_with_peer(H256::zero(), &client);
+        let ss = TestSnapshotService::new();
+        let mut io = TestIo::new(&mut client, &ss, &queue, None);
+
+        let mut node_list = RlpStream::new_list(3);
+        node_list.append(
+            &H256::from_str("0000000000000000000000000000000000000000000000005555555555555555")
+                .unwrap(),
+        );
+        node_list.append(
+            &H256::from_str("ffffffffffffffffffffffffffffffffffffffffffffaaaaaaaaaaaaaaaaaaaa")
+                .unwrap(),
+        );
+        node_list.append(
+            &H256::from_str("aff0000000000000000000000000000000000000000000000000000000000000")
+                .unwrap(),
+        );
+
+        let node_request = node_list.out();
+        // it returns rlp ONLY for hashes started with "f"
+        let result = SyncSupplier::return_node_data(&io, &Rlp::new(&node_request.clone()), 0);
+
+        assert!(result.is_ok());
+        let rlp_result = result.unwrap();
+        assert!(rlp_result.is_some());
+
+        // the length of one rlp-encoded hashe
+        let rlp = rlp_result.unwrap().1.out();
+        let rlp = Rlp::new(&rlp);
+        assert_eq!(Ok(1), rlp.item_count());
+
+        io.sender = Some(2usize);
+
+        SyncSupplier::dispatch_packet(
+            &RwLock::new(sync),
+            &mut io,
+            0usize,
+            GetNodeDataPacket.id(),
+            &node_request,
+        );
+        assert_eq!(1, io.packets.len());
+    }
 }

crates/ethcore/sync/src/chain/sync_packet.rs

@@ -48,8 +48,8 @@ pub enum SyncPacket {
     GetPooledTransactionsPacket = 0x09,
     PooledTransactionsPacket = 0x0a,
 
-    //GetNodeDataPacket = 0x0d,
+    GetNodeDataPacket = 0x0d,
-    //NodeDataPacket = 0x0e,
+    NodeDataPacket = 0x0e,
     GetReceiptsPacket = 0x0f,
     ReceiptsPacket = 0x10,
 
@@ -87,8 +87,8 @@ impl PacketInfo for SyncPacket {
             | NewPooledTransactionHashesPacket
             | GetPooledTransactionsPacket
             | PooledTransactionsPacket
-            //| GetNodeDataPacket
+            | GetNodeDataPacket
-            //| NodeDataPacket
+            | NodeDataPacket
             | GetReceiptsPacket
             | ReceiptsPacket => ETH_PROTOCOL,
 
@@ -105,7 +105,6 @@ impl PacketInfo for SyncPacket {
     }
 
     fn has_request_id_in_eth_66(&self) -> bool {
-        // Note: NodeDataPacket and GetNodeDataPacket also get a request id in eth-66.
         match self {
             GetBlockHeadersPacket
             | BlockHeadersPacket
@@ -113,6 +112,8 @@ impl PacketInfo for SyncPacket {
             | BlockBodiesPacket
             | GetPooledTransactionsPacket
             | PooledTransactionsPacket
+            | GetNodeDataPacket
+            | NodeDataPacket
             | GetReceiptsPacket
             | ReceiptsPacket => true,
             _ => false,