Synchronizer asks for approval-pending transaction from peer if needed

src/main/java/org/qora/controller/Controller.java

@@ -37,6 +37,7 @@ import org.qora.network.message.GetBlockSummariesMessage;
 import org.qora.network.message.GetPeersMessage;
 import org.qora.network.message.GetSignaturesMessage;
 import org.qora.network.message.GetSignaturesV2Message;
+import org.qora.network.message.GetTransactionMessage;
 import org.qora.network.message.HeightMessage;
 import org.qora.network.message.HeightV2Message;
 import org.qora.network.message.Message;
@@ -500,7 +501,7 @@ public class Controller extends Thread {
 				break;
 			}
 
-			case GET_BLOCK:
+			case GET_BLOCK: {
 				GetBlockMessage getBlockMessage = (GetBlockMessage) message;
 				byte[] signature = getBlockMessage.getSignature();
 
@@ -522,6 +523,29 @@ public class Controller extends Thread {
 					LOGGER.error(String.format("Repository issue while send block %s to peer %s", Base58.encode(signature), peer), e);
 				}
 				break;
+			}
+
+			case GET_TRANSACTION: {
+				GetTransactionMessage getTransactionMessage = (GetTransactionMessage) message;
+				byte[] signature = getTransactionMessage.getSignature();
+
+				try (final Repository repository = RepositoryManager.getRepository()) {
+					TransactionData transactionData = repository.getTransactionRepository().fromSignature(signature);
+					if (transactionData == null) {
+						LOGGER.debug(String.format("Ignoring GET_TRANSACTION request from peer %s for unknown transaction %s", peer, Base58.encode(signature)));
+						// Send no response at all???
+						break;
+					}
+
+					Message transactionMessage = new TransactionMessage(transactionData);
+					transactionMessage.setId(message.getId());
+					if (!peer.sendMessage(transactionMessage))
+						peer.disconnect("failed to send transaction");
+				} catch (DataException e) {
+					LOGGER.error(String.format("Repository issue while send transaction %s to peer %s", Base58.encode(signature), peer), e);
+				}
+				break;
+			}
 
 			case TRANSACTION:
 				TransactionMessage transactionMessage = (TransactionMessage) message;

src/main/java/org/qora/controller/Synchronizer.java

@@ -13,6 +13,8 @@ import org.qora.block.BlockChain;
 import org.qora.block.GenesisBlock;
 import org.qora.data.block.BlockData;
 import org.qora.data.network.BlockSummaryData;
+import org.qora.data.transaction.GroupApprovalTransactionData;
+import org.qora.data.transaction.TransactionData;
 import org.qora.network.Peer;
 import org.qora.network.message.BlockMessage;
 import org.qora.network.message.BlockSummariesMessage;
@@ -20,13 +22,17 @@ import org.qora.network.message.GetBlockMessage;
 import org.qora.network.message.GetBlockSummariesMessage;
 import org.qora.network.message.GetSignaturesMessage;
 import org.qora.network.message.GetSignaturesV2Message;
+import org.qora.network.message.GetTransactionMessage;
 import org.qora.network.message.Message;
 import org.qora.network.message.Message.MessageType;
 import org.qora.network.message.SignaturesMessage;
+import org.qora.network.message.TransactionMessage;
 import org.qora.repository.DataException;
 import org.qora.repository.Repository;
 import org.qora.repository.RepositoryManager;
 import org.qora.transaction.Transaction;
+import org.qora.transaction.Transaction.TransactionType;
+import org.qora.utils.Base58;
 import org.qora.utils.NTP;
 
 public class Synchronizer {
@@ -231,6 +237,46 @@ public class Synchronizer {
 								return SynchronizationResult.NO_REPLY;
 							}
 
+							// If block contains GROUP_APPROVAL transactions then we need to make sure we have the relevant pending transactions too
+							for (Transaction transaction : newBlock.getTransactions()) {
+								TransactionData transactionData = transaction.getTransactionData();
+
+								if (transactionData.getType() != TransactionType.GROUP_APPROVAL)
+									continue;
+
+								GroupApprovalTransactionData groupApprovalTransactionData = (GroupApprovalTransactionData) transactionData;
+
+								byte[] pendingSignature = groupApprovalTransactionData.getPendingSignature();
+
+								if (repository.getTransactionRepository().exists(pendingSignature))
+									continue;
+
+								LOGGER.debug(String.format("Fetching unknown approval-pending transaction %s from peer %s, needed for block at height %d", Base58.encode(pendingSignature), peer, ourHeight));
+
+								TransactionData pendingTransactionData = this.fetchTransaction(peer, pendingSignature);
+								if (pendingTransactionData == null) {
+									LOGGER.info(String.format("Peer %s failed to respond with pending transaction %s", peer, Base58.encode(pendingSignature)));
+									return SynchronizationResult.NO_REPLY;
+								}
+
+								// Check the signature is valid at least!
+								Transaction pendingTransaction = Transaction.fromData(repository, pendingTransactionData);
+								if (!pendingTransaction.isSignatureValid()) {
+									LOGGER.info(String.format("Peer %s sent pending transaction %s with invalid signature", peer, Base58.encode(pendingSignature)));
+									return SynchronizationResult.INVALID_DATA;
+								}
+
+								Transaction.ValidationResult transactionResult = pendingTransaction.isValidUnconfirmed();
+								if (transactionResult != Transaction.ValidationResult.OK) {
+									LOGGER.info(String.format("Peer %s sent invalid (%s) pending transaction %s", peer, transactionResult.name(), Base58.encode(pendingSignature)));
+									return SynchronizationResult.INVALID_DATA;
+								}
+
+								// Add to our unconfirmed pile
+								this.repository.getTransactionRepository().save(pendingTransactionData);
+								this.repository.getTransactionRepository().unconfirmTransaction(pendingTransactionData);
+							}
+
 							if (!newBlock.isSignatureValid()) {
 								LOGGER.info(String.format("Peer %s sent block with invalid signature for height %d", peer, ourHeight));
 								return SynchronizationResult.INVALID_DATA;
@@ -391,4 +437,16 @@ public class Synchronizer {
 		}
 	}
 
+	private TransactionData fetchTransaction(Peer peer, byte[] signature) {
+		Message getTransactionMessage = new GetTransactionMessage(signature);
+
+		Message message = peer.getResponse(getTransactionMessage);
+		if (message == null || message.getType() != MessageType.TRANSACTION)
+			return null;
+
+		TransactionMessage transactionMessage = (TransactionMessage) message;
+
+		return transactionMessage.getTransactionData();
+	}
+
 }

src/main/java/org/qora/network/message/GetTransactionMessage.java

@@ -0,0 +1,54 @@
+package org.qora.network.message;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.UnsupportedEncodingException;
+import java.nio.ByteBuffer;
+
+import org.qora.transform.Transformer;
+
+public class GetTransactionMessage extends Message {
+
+	private static final int TRANSACTION_SIGNATURE_LENGTH = Transformer.SIGNATURE_LENGTH;
+
+	private byte[] signature;
+
+	public GetTransactionMessage(byte[] signature) {
+		this(-1, signature);
+	}
+
+	private GetTransactionMessage(int id, byte[] signature) {
+		super(id, MessageType.GET_TRANSACTION);
+
+		this.signature = signature;
+	}
+
+	public byte[] getSignature() {
+		return this.signature;
+	}
+
+	public static Message fromByteBuffer(int id, ByteBuffer bytes) throws UnsupportedEncodingException {
+		if (bytes.remaining() != TRANSACTION_SIGNATURE_LENGTH)
+			return null;
+
+		byte[] signature = new byte[TRANSACTION_SIGNATURE_LENGTH];
+
+		bytes.get(signature);
+
+		return new GetTransactionMessage(id, signature);
+	}
+
+	@Override
+	protected byte[] toData() {
+		try {
+			ByteArrayOutputStream bytes = new ByteArrayOutputStream();
+
+			bytes.write(this.signature);
+
+			return bytes.toByteArray();
+		} catch (IOException e) {
+			return null;
+		}
+	}
+
+}

src/main/java/org/qora/network/message/Message.java

@@ -64,7 +64,8 @@ public abstract class Message {
 		GET_SIGNATURES_V2(16),
 		PEER_VERIFY(17),
 		VERIFICATION_CODES(18),
-		HEIGHT_V2(19);
+		HEIGHT_V2(19),
+		GET_TRANSACTION(20);
 
 		public final int value;
 		public final Method fromByteBuffer;