Incremental Optimization(s) on BlockBroadcaster (#911)

--> adapt `BlockBroadcaster` to use `send` method on `EthPeer`

--> adapt `EthProtocolMamnager` to utilize `BlockBroadcaster` to disseminate newly mined block

Signed-off-by: Adrian Sutton <adrian.sutton@consensys.net>

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/manager/EthPeer.java

@@ -14,7 +14,6 @@ package tech.pegasys.pantheon.ethereum.eth.manager;
 
 import static com.google.common.base.Preconditions.checkArgument;
 
-import tech.pegasys.pantheon.ethereum.core.Block;
 import tech.pegasys.pantheon.ethereum.core.Hash;
 import tech.pegasys.pantheon.ethereum.eth.manager.ChainState.EstimatedHeightListener;
 import tech.pegasys.pantheon.ethereum.eth.manager.RequestManager.ResponseStream;
@@ -24,7 +23,6 @@ import tech.pegasys.pantheon.ethereum.eth.messages.GetBlockBodiesMessage;
 import tech.pegasys.pantheon.ethereum.eth.messages.GetBlockHeadersMessage;
 import tech.pegasys.pantheon.ethereum.eth.messages.GetNodeDataMessage;
 import tech.pegasys.pantheon.ethereum.eth.messages.GetReceiptsMessage;
-import tech.pegasys.pantheon.ethereum.eth.messages.NewBlockMessage;
 import tech.pegasys.pantheon.ethereum.p2p.api.MessageData;
 import tech.pegasys.pantheon.ethereum.p2p.api.PeerConnection;
 import tech.pegasys.pantheon.ethereum.p2p.api.PeerConnection.PeerNotConnected;
@@ -132,16 +130,6 @@ public class EthPeer {
     }
   }
 
-  public void propagateBlock(final Block block, final UInt256 totalDifficulty) {
-    registerKnownBlock(block.getHash());
-    final NewBlockMessage newBlockMessage = NewBlockMessage.create(block, totalDifficulty);
-    try {
-      connection.sendForProtocol(protocolName, newBlockMessage);
-    } catch (PeerNotConnected e) {
-      LOG.trace("Failed to broadcast new block to peer", e);
-    }
-  }
-
   public ResponseStream getHeadersByHash(
       final Hash hash, final int maxHeaders, final int skip, final boolean reverse)
       throws PeerNotConnected {

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/manager/EthProtocolManager.java

@@ -20,8 +20,8 @@ import tech.pegasys.pantheon.ethereum.core.Block;
 import tech.pegasys.pantheon.ethereum.core.Hash;
 import tech.pegasys.pantheon.ethereum.eth.EthProtocol;
 import tech.pegasys.pantheon.ethereum.eth.messages.EthPV62;
-import tech.pegasys.pantheon.ethereum.eth.messages.NewBlockMessage;
 import tech.pegasys.pantheon.ethereum.eth.messages.StatusMessage;
+import tech.pegasys.pantheon.ethereum.eth.sync.BlockBroadcaster;
 import tech.pegasys.pantheon.ethereum.p2p.api.Message;
 import tech.pegasys.pantheon.ethereum.p2p.api.MessageData;
 import tech.pegasys.pantheon.ethereum.p2p.api.PeerConnection;
@@ -37,7 +37,6 @@ import tech.pegasys.pantheon.util.uint.UInt256;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
-import java.util.Optional;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicBoolean;
 
@@ -64,6 +63,7 @@ public class EthProtocolManager implements ProtocolManager, MinedBlockObserver {
   private final boolean fastSyncEnabled;
   private List<Capability> supportedCapabilities;
   private final Blockchain blockchain;
+  private final BlockBroadcaster blockBroadcaster;
 
   EthProtocolManager(
       final Blockchain blockchain,
@@ -73,7 +73,6 @@ public class EthProtocolManager implements ProtocolManager, MinedBlockObserver {
       final int requestLimit,
       final EthScheduler scheduler) {
     this.networkId = networkId;
-
     this.scheduler = scheduler;
     this.blockchain = blockchain;
     this.fastSyncEnabled = fastSyncEnabled;
@@ -85,6 +84,8 @@ public class EthProtocolManager implements ProtocolManager, MinedBlockObserver {
     ethMessages = new EthMessages();
     ethContext = new EthContext(getSupportedProtocol(), ethPeers, ethMessages, scheduler);
 
+    this.blockBroadcaster = new BlockBroadcaster(ethContext);
+
     // Set up request handlers
     new EthServer(blockchain, worldStateArchive, ethMessages, requestLimit);
   }
@@ -271,24 +272,13 @@ public class EthProtocolManager implements ProtocolManager, MinedBlockObserver {
   @Override
   public void blockMined(final Block block) {
     // This assumes the block has already been included in the chain
-
-    final Optional<UInt256> totalDifficulty = blockchain.getTotalDifficultyByHash(block.getHash());
-    if (!totalDifficulty.isPresent()) {
-      throw new IllegalStateException(
-          "Unable to get total difficulty from blockchain for mined block.");
-    }
-
-    final NewBlockMessage newBlockMessage = NewBlockMessage.create(block, totalDifficulty.get());
-
-    ethPeers
-        .availablePeers()
-        .forEach(
-            peer -> {
-              try {
-                peer.send(newBlockMessage);
-              } catch (final PeerNotConnected ex) {
-                // Peers may disconnect while traversing the list, this is a normal occurrence.
-              }
-            });
+    final UInt256 totalDifficulty =
+        blockchain
+            .getTotalDifficultyByHash(block.getHash())
+            .orElseThrow(
+                () ->
+                    new IllegalStateException(
+                        "Unable to get total difficulty from blockchain for mined block."));
+    blockBroadcaster.propagate(block, totalDifficulty);
   }
 }

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/BlockBroadcaster.java

@@ -14,21 +14,36 @@ package tech.pegasys.pantheon.ethereum.eth.sync;
 
 import tech.pegasys.pantheon.ethereum.core.Block;
 import tech.pegasys.pantheon.ethereum.eth.manager.EthContext;
+import tech.pegasys.pantheon.ethereum.eth.messages.NewBlockMessage;
+import tech.pegasys.pantheon.ethereum.p2p.api.PeerConnection;
 import tech.pegasys.pantheon.util.uint.UInt256;
 
-class BlockBroadcaster {
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class BlockBroadcaster {
+  private static final Logger LOG = LogManager.getLogger();
 
   private final EthContext ethContext;
 
-  BlockBroadcaster(final EthContext ethContext) {
+  public BlockBroadcaster(final EthContext ethContext) {
     this.ethContext = ethContext;
   }
 
-  void propagate(final Block block, final UInt256 difficulty) {
+  public void propagate(final Block block, final UInt256 totalDifficulty) {
+    final NewBlockMessage newBlockMessage = NewBlockMessage.create(block, totalDifficulty);
     ethContext
         .getEthPeers()
         .availablePeers()
         .filter(ethPeer -> !ethPeer.hasSeenBlock(block.getHash()))
-        .forEach(ethPeer -> ethPeer.propagateBlock(block, difficulty));
+        .forEach(
+            ethPeer -> {
+              ethPeer.registerKnownBlock(block.getHash());
+              try {
+                ethPeer.send(newBlockMessage);
+              } catch (PeerConnection.PeerNotConnected e) {
+                LOG.trace("Failed to broadcast new block to peer", e);
+              }
+            });
   }
 }

ethereum/eth/src/main/java/tech/pegasys/pantheon/ethereum/eth/sync/BlockPropagationManager.java

@@ -110,7 +110,7 @@ public class BlockPropagationManager<C> {
         .subscribe(EthPV62.NEW_BLOCK_HASHES, this::handleNewBlockHashesFromNetwork);
   }
 
-  protected void validateAndBroadcastBlock(final Block block) {
+  private void validateAndBroadcastBlock(final Block block) {
     final ProtocolSpec<C> protocolSpec =
         protocolSchedule.getByBlockNumber(block.getHeader().getNumber());
     final BlockHeaderValidator<C> blockHeaderValidator = protocolSpec.getBlockHeaderValidator();

ethereum/eth/src/test/java/tech/pegasys/pantheon/ethereum/eth/sync/BlockBroadcasterTest.java

@@ -25,6 +25,8 @@ import tech.pegasys.pantheon.ethereum.core.BlockHeaderTestFixture;
 import tech.pegasys.pantheon.ethereum.eth.manager.EthContext;
 import tech.pegasys.pantheon.ethereum.eth.manager.EthPeer;
 import tech.pegasys.pantheon.ethereum.eth.manager.EthPeers;
+import tech.pegasys.pantheon.ethereum.eth.messages.NewBlockMessage;
+import tech.pegasys.pantheon.ethereum.p2p.api.PeerConnection;
 import tech.pegasys.pantheon.util.uint.UInt256;
 
 import java.util.Collections;
@@ -35,7 +37,7 @@ import org.junit.Test;
 public class BlockBroadcasterTest {
 
   @Test
-  public void blockPropagationUnitTest() {
+  public void blockPropagationUnitTest() throws PeerConnection.PeerNotConnected {
     final EthPeer ethPeer = mock(EthPeer.class);
     final EthPeers ethPeers = mock(EthPeers.class);
     when(ethPeers.availablePeers()).thenReturn(Stream.of(ethPeer));
@@ -45,14 +47,16 @@ public class BlockBroadcasterTest {
 
     final BlockBroadcaster blockBroadcaster = new BlockBroadcaster(ethContext);
     final Block block = generateBlock();
+    final NewBlockMessage newBlockMessage =
+        NewBlockMessage.create(block, block.getHeader().getDifficulty());
 
     blockBroadcaster.propagate(block, UInt256.ZERO);
 
-    verify(ethPeer, times(1)).propagateBlock(any(), any());
+    verify(ethPeer, times(1)).send(newBlockMessage);
   }
 
   @Test
-  public void blockPropagationUnitTestSeenUnseen() {
+  public void blockPropagationUnitTestSeenUnseen() throws PeerConnection.PeerNotConnected {
     final EthPeer ethPeer0 = mock(EthPeer.class);
     when(ethPeer0.hasSeenBlock(any())).thenReturn(true);
 
@@ -66,10 +70,13 @@ public class BlockBroadcasterTest {
 
     final BlockBroadcaster blockBroadcaster = new BlockBroadcaster(ethContext);
     final Block block = generateBlock();
+    final NewBlockMessage newBlockMessage =
+        NewBlockMessage.create(block, block.getHeader().getDifficulty());
+
     blockBroadcaster.propagate(block, UInt256.ZERO);
 
-    verify(ethPeer0, never()).propagateBlock(any(), any());
-    verify(ethPeer1, times(1)).propagateBlock(any(), any());
+    verify(ethPeer0, never()).send(newBlockMessage);
+    verify(ethPeer1, times(1)).send(newBlockMessage);
   }
 
   private Block generateBlock() {