Fix possibility of a vote error breaking ledger (#1768)

* Fix possibility of a vote error breaking ledger

* Add test

src/replicate_stage.rs

@@ -61,7 +61,8 @@ impl ReplicateStage {
         vote_blob_sender: Option<&BlobSender>,
         ledger_entry_sender: &EntrySender,
         entry_height: &mut u64,
-    ) -> Result<Hash> {
+        last_entry_id: &mut Option<Hash>,
+    ) -> Result<()> {
         let timer = Duration::new(1, 0);
         //coalesce all the available entries into a single vote
         let mut entries = window_receiver.recv_timeout(timer)?;
@@ -76,7 +77,6 @@ impl ReplicateStage {
         );
 
         let mut res = Ok(());
-        let last_entry_id = {
         let mut num_entries_to_write = entries.len();
         let (current_leader, _) = bank
             .get_current_leader()
@@ -110,15 +110,12 @@ impl ReplicateStage {
 
         // If leader rotation happened, only write the entries up to leader rotation.
         entries.truncate(num_entries_to_write);
+        *last_entry_id = Some(
             entries
                 .last()
                 .expect("Entries cannot be empty at this point")
-                .id
+                .id,
-        };
+        );
-
-        if let Some(sender) = vote_blob_sender {
-            send_validator_vote(bank, vote_account_keypair, &cluster_info, sender)?;
-        }
 
         inc_new_counter_info!(
             "replicate-transactions",
@@ -136,7 +133,11 @@ impl ReplicateStage {
 
         *entry_height += entries_len;
         res?;
-        Ok(last_entry_id)
+        if let Some(sender) = vote_blob_sender {
+            send_validator_vote(bank, vote_account_keypair, &cluster_info, sender)?;
+        }
+
+        Ok(())
     }
 
     pub fn new(
@@ -197,13 +198,12 @@ impl ReplicateStage {
                         vote_sender,
                         &ledger_entry_sender,
                         &mut entry_height_,
+                        &mut last_entry_id,
                     ) {
                         Err(Error::RecvTimeoutError(RecvTimeoutError::Disconnected)) => break,
                         Err(Error::RecvTimeoutError(RecvTimeoutError::Timeout)) => (),
                         Err(e) => error!("{:?}", e),
-                        Ok(last_entry_id_) => {
+                        Ok(()) => (),
-                            last_entry_id = Some(last_entry_id_);
-                        }
                     }
                 }
 
@@ -234,16 +234,19 @@ mod test {
     use cluster_info::{ClusterInfo, Node};
     use entry::Entry;
     use fullnode::Fullnode;
+    use hash::Hash;
     use leader_scheduler::{make_active_set_entries, LeaderScheduler, LeaderSchedulerConfig};
-    use ledger::{create_tmp_sample_ledger, LedgerWriter};
+    use ledger::{create_ticks, create_tmp_sample_ledger, LedgerWriter};
     use logger;
     use replicate_stage::{ReplicateStage, ReplicateStageReturnType};
+    use result::Error;
     use service::Service;
     use signature::{Keypair, KeypairUtil};
     use std::fs::remove_dir_all;
     use std::sync::atomic::{AtomicBool, Ordering};
     use std::sync::mpsc::channel;
     use std::sync::{Arc, RwLock};
+    use vote_stage::{send_validator_vote, VoteError};
 
     #[test]
     pub fn test_replicate_stage_leader_rotation_exit() {
@@ -309,7 +312,7 @@ mod test {
         // Set up the replicate stage
         let (entry_sender, entry_receiver) = channel();
         let exit = Arc::new(AtomicBool::new(false));
-        let (replicate_stage, _ledger_writer_recv) = ReplicateStage::new(
+        let (replicate_stage, ledger_writer_recv) = ReplicateStage::new(
             Arc::new(my_keypair),
             Arc::new(vote_account_keypair),
             Arc::new(bank),
@@ -335,11 +338,233 @@ mod test {
 
         // Add on the only entries that weren't ticks to the bootstrap height to get the
         // total expected entry length
+        let leader_rotation_index = (bootstrap_height - initial_tick_height - 1) as usize;
         let expected_entry_height =
             bootstrap_height + initial_non_tick_height + active_set_entries_len;
-        let expected_last_id =
+        let expected_last_id = entries_to_send[leader_rotation_index].id;
-            entries_to_send[(bootstrap_height - initial_tick_height - 1) as usize].id;
+        entry_sender.send(entries_to_send.clone()).unwrap();
-        entry_sender.send(entries_to_send).unwrap();
+
+        // Wait for replicate_stage to exit and check return value is correct
+        assert_eq!(
+            Some(ReplicateStageReturnType::LeaderRotation(
+                bootstrap_height,
+                expected_entry_height,
+                expected_last_id,
+            )),
+            replicate_stage.join().expect("replicate stage join")
+        );
+
+        // Check that the entries on the ledger writer channel are correct
+        let received_ticks = ledger_writer_recv
+            .recv()
+            .expect("Expected to recieve an entry on the ledger writer receiver");
+
+        assert_eq!(
+            &received_ticks[..],
+            &entries_to_send[..leader_rotation_index + 1]
+        );
+
+        assert_eq!(exit.load(Ordering::Relaxed), true);
+
+        let _ignored = remove_dir_all(&my_ledger_path);
+    }
+
+    #[test]
+    fn test_vote_error_replicate_stage_correctness() {
+        // Set up dummy node to host a ReplicateStage
+        let my_keypair = Keypair::new();
+        let my_id = my_keypair.pubkey();
+        let my_node = Node::new_localhost_with_pubkey(my_id);
+
+        // Create keypair for the leader
+        let leader_id = Keypair::new().pubkey();
+        let leader_scheduler = Arc::new(RwLock::new(LeaderScheduler::default()));
+
+        let num_ending_ticks = 0;
+        let (_, my_ledger_path, genesis_entries) = create_tmp_sample_ledger(
+            "test_vote_error_replicate_stage_correctness",
+            10_000,
+            num_ending_ticks,
+            leader_id,
+            500,
+        );
+
+        let initial_entry_len = genesis_entries.len();
+
+        // Set up the bank
+        let (bank, _, _) = Fullnode::new_bank_from_ledger(&my_ledger_path, leader_scheduler);
+
+        // Set up the cluster info
+        let cluster_info_me = Arc::new(RwLock::new(
+            ClusterInfo::new(my_node.info.clone()).expect("ClusterInfo::new"),
+        ));
+
+        // Set up the replicate stage
+        let vote_account_keypair = Arc::new(Keypair::new());
+        let bank = Arc::new(bank);
+        let (entry_sender, entry_receiver) = channel();
+        let exit = Arc::new(AtomicBool::new(false));
+        let (replicate_stage, ledger_writer_recv) = ReplicateStage::new(
+            Arc::new(my_keypair),
+            vote_account_keypair.clone(),
+            bank.clone(),
+            cluster_info_me.clone(),
+            entry_receiver,
+            exit.clone(),
+            initial_entry_len as u64,
+        );
+
+        // Vote sender should error because no leader contact info is found in the
+        // ClusterInfo
+        let (mock_sender, _mock_receiver) = channel();
+        let vote_err =
+            send_validator_vote(&bank, &vote_account_keypair, &cluster_info_me, &mock_sender);
+        if let Err(Error::VoteError(vote_error)) = vote_err {
+            assert_eq!(vote_error, VoteError::LeaderInfoNotFound);
+        } else {
+            panic!("Expected validator vote to fail with LeaderInfoNotFound");
+        }
+
+        // Send ReplicateStage an entry, should see it on the ledger writer receiver
+        let next_tick = create_ticks(
+            1,
+            genesis_entries
+                .last()
+                .expect("Expected nonzero number of entries in genesis")
+                .id,
+        );
+        entry_sender
+            .send(next_tick.clone())
+            .expect("Error sending entry to ReplicateStage");
+        let received_tick = ledger_writer_recv
+            .recv()
+            .expect("Expected to recieve an entry on the ledger writer receiver");
+
+        assert_eq!(next_tick, received_tick);
+        drop(entry_sender);
+        replicate_stage
+            .join()
+            .expect("Expect successful ReplicateStage exit");
+        let _ignored = remove_dir_all(&my_ledger_path);
+    }
+
+    #[test]
+    fn test_vote_error_replicate_stage_leader_rotation() {
+        // Set up dummy node to host a ReplicateStage
+        let my_keypair = Keypair::new();
+        let my_id = my_keypair.pubkey();
+        let my_node = Node::new_localhost_with_pubkey(my_id);
+
+        // Create keypair for the leader
+        let leader_id = Keypair::new().pubkey();
+
+        // Create the ledger
+        let (mint, my_ledger_path, genesis_entries) = create_tmp_sample_ledger(
+            "test_vote_error_replicate_stage_leader_rotation",
+            10_000,
+            0,
+            leader_id,
+            500,
+        );
+
+        let mut last_id = genesis_entries
+            .last()
+            .expect("expected at least one genesis entry")
+            .id;
+
+        // Write two entries to the ledger so that the validator is in the active set:
+        // 1) Give the validator a nonzero number of tokens 2) A vote from the validator.
+        // This will cause leader rotation after the bootstrap height
+        let mut ledger_writer = LedgerWriter::open(&my_ledger_path, false).unwrap();
+        let (active_set_entries, vote_account_keypair) =
+            make_active_set_entries(&my_keypair, &mint.keypair(), &last_id, &last_id, 0);
+        last_id = active_set_entries.last().unwrap().id;
+        let initial_tick_height = genesis_entries
+            .iter()
+            .skip(2)
+            .fold(0, |tick_count, entry| tick_count + entry.is_tick() as u64);
+        let active_set_entries_len = active_set_entries.len() as u64;
+        let initial_non_tick_height = genesis_entries.len() as u64 - initial_tick_height;
+        let initial_entry_len = genesis_entries.len() as u64 + active_set_entries_len;
+        ledger_writer.write_entries(&active_set_entries).unwrap();
+
+        // Set up the LeaderScheduler so that this this node becomes the leader at
+        // bootstrap_height = num_bootstrap_slots * leader_rotation_interval
+        let leader_rotation_interval = 10;
+        let num_bootstrap_slots = 2;
+        let bootstrap_height = num_bootstrap_slots * leader_rotation_interval;
+        let leader_scheduler_config = LeaderSchedulerConfig::new(
+            Some(bootstrap_height),
+            Some(leader_rotation_interval),
+            Some(leader_rotation_interval * 2),
+            Some(bootstrap_height),
+        );
+
+        let leader_scheduler =
+            Arc::new(RwLock::new(LeaderScheduler::new(&leader_scheduler_config)));
+
+        // Set up the bank
+        let (bank, _, _) = Fullnode::new_bank_from_ledger(&my_ledger_path, leader_scheduler);
+
+        // Set up the cluster info
+        let cluster_info_me = Arc::new(RwLock::new(
+            ClusterInfo::new(my_node.info.clone()).expect("ClusterInfo::new"),
+        ));
+
+        // Set up the replicate stage
+        let vote_account_keypair = Arc::new(vote_account_keypair);
+        let bank = Arc::new(bank);
+        let (entry_sender, entry_receiver) = channel();
+        let exit = Arc::new(AtomicBool::new(false));
+        let (replicate_stage, ledger_writer_recv) = ReplicateStage::new(
+            Arc::new(my_keypair),
+            vote_account_keypair.clone(),
+            bank.clone(),
+            cluster_info_me.clone(),
+            entry_receiver,
+            exit.clone(),
+            initial_entry_len as u64,
+        );
+
+        // Vote sender should error because no leader contact info is found in the
+        // ClusterInfo
+        let (mock_sender, _mock_receiver) = channel();
+        let vote_err =
+            send_validator_vote(&bank, &vote_account_keypair, &cluster_info_me, &mock_sender);
+        if let Err(Error::VoteError(vote_error)) = vote_err {
+            assert_eq!(vote_error, VoteError::LeaderInfoNotFound);
+        } else {
+            panic!("Expected validator vote to fail with LeaderInfoNotFound");
+        }
+
+        // Send enough ticks to trigger leader rotation
+        let total_entries_to_send = (bootstrap_height - initial_tick_height) as usize;
+        let num_hashes = 1;
+
+        // Add on the only entries that weren't ticks to the bootstrap height to get the
+        // total expected entry length
+        let expected_entry_height =
+            bootstrap_height + initial_non_tick_height + active_set_entries_len;
+        let leader_rotation_index = (bootstrap_height - initial_tick_height - 1) as usize;
+        let mut expected_last_id = Hash::default();
+        for i in 0..total_entries_to_send {
+            let entry = Entry::new(&mut last_id, num_hashes, vec![]);
+            last_id = entry.id;
+            entry_sender
+                .send(vec![entry.clone()])
+                .expect("Expected to be able to send entry to ReplicateStage");
+            // Check that the entries on the ledger writer channel are correct
+            let received_entry = ledger_writer_recv
+                .recv()
+                .expect("Expected to recieve an entry on the ledger writer receiver");
+            assert_eq!(received_entry[0], entry);
+
+            if i == leader_rotation_index {
+                expected_last_id = entry.id;
+            }
+        }
+
+        assert_ne!(expected_last_id, Hash::default());
 
         // Wait for replicate_stage to exit and check return value is correct
         assert_eq!(
@@ -352,7 +577,6 @@ mod test {
         );
 
         assert_eq!(exit.load(Ordering::Relaxed), true);
-
         let _ignored = remove_dir_all(&my_ledger_path);
     }
 }