使用 Java SDK Client for Hyperledger Fabric V1.0 的应用程序在调用链码时无限期等待

Question

按照Building Your First Network 的步骤，我的Hyperledger Fabric V1.0 网络已启动并运行。

现在我可以创建频道、安装/实例化/调用/查询链码等。

现在我正在尝试创建一些资产并使用 Java SDK Client 进行查询。

我创建了以下方法来从我的 java 应用程序中调用和查询链代码。

void createChannel() throws InvalidArgumentException, TransactionException, IOException, ProposalException{
    Properties ordererProperties = getOrdererProperties("orderer.example.com");
    ordererProperties.put("grpc.NettyChannelBuilderOption.keepAliveTime", new Object[] {5L, TimeUnit.MINUTES});
    ordererProperties.put("grpc.NettyChannelBuilderOption.keepAliveTimeout", new Object[] {8L, TimeUnit.SECONDS});
    Orderer orderer = client.newOrderer("orderer.example.com", "grpcs://192.168.99.100:7050",ordererProperties);

    Properties peerProperties = getPeerProperties("peer0.org1.example.com"); //test properties for peer.. if any.
    if (peerProperties == null) {
        peerProperties = new Properties();
    }
    peerProperties.put("grpc.NettyChannelBuilderOption.maxInboundMessageSize", 9000000);
    Peer peer = client.newPeer("peer0.org1.example.com", "grpcs://192.168.99.100:7051",peerProperties);
    channel = client.newChannel("testchannel");
    channel.addOrderer(orderer);
    channel.addPeer(peer);
    channel.initialize();
}

void creteTransactionalProposal(){
    proposalRequest = client.newTransactionProposalRequest();
    final ChaincodeID chaincodeID = ChaincodeID.newBuilder()
            .setName("asset_test")
            .setVersion("1.0")
            .setPath("github.com/myuser/myfabricrepo/asset_chain")
            .build();

    proposalRequest.setChaincodeID(chaincodeID);
    proposalRequest.setFcn("set");
    proposalRequest.setProposalWaitTime(TimeUnit.SECONDS.toMillis(1));
    proposalRequest.setArgs(new String[]{"a1", "a1_val"});
}

void sendProposal() throws ProposalException, InvalidArgumentException, InterruptedException, ExecutionException{
    final Collection<ProposalResponse> responses = channel.sendTransactionProposal(proposalRequest);
    CompletableFuture<BlockEvent.TransactionEvent> txFuture = channel.sendTransaction(responses, client.getUserContext());
    BlockEvent.TransactionEvent event = txFuture.get();//waiting indefinitely
    System.out.println(event.toString());
    //query();
}

void query() throws InvalidArgumentException, ProposalException{
     final ChaincodeID chaincodeID = ChaincodeID.newBuilder()
                .setName(""asset_test"")
                .setVersion("1.0")
                .setPath("github.com/myuser/myfabricrepo/asset_chain")
                .build();

    QueryByChaincodeRequest queryByChaincodeRequest = client.newQueryProposalRequest();
    queryByChaincodeRequest.setArgs(new String[] {"a1"});
    queryByChaincodeRequest.setFcn("get");
    queryByChaincodeRequest.setChaincodeID(chaincodeID);

    Map<String, byte[]> tm2 = new HashMap<>();
    tm2.put("HyperLedgerFabric", "QueryByChaincodeRequest:JavaSDK".getBytes(UTF_8));
    tm2.put("method", "QueryByChaincodeRequest".getBytes(UTF_8));
    queryByChaincodeRequest.setTransientMap(tm2);

    Collection<ProposalResponse> queryProposals = channel.queryByChaincode(queryByChaincodeRequest, channel.getPeers());
    for (ProposalResponse proposalResponse : queryProposals) {
        if (!proposalResponse.isVerified()
                || proposalResponse.getStatus() != ProposalResponse.Status.SUCCESS) {
            System.out.println("Failed query proposal from peer " + proposalResponse.getPeer().getName() + " status: "
                    + proposalResponse.getStatus() + ". Messages: " + proposalResponse.getMessage()
                    + ". Was verified : " + proposalResponse.isVerified());
        } else {
            String payload = proposalResponse.getProposalResponse().getResponse().getPayload()
                    .toStringUtf8();
            System.out.printf("\nQuery payload of b from peer %s returned %s", proposalResponse.getPeer().getName(),
                    payload);
            //assertEquals(payload, expect);
        }
    }
}

我可以通过调用来创建资产

t.creteTransactionalProposal();
t.sendProposal();

但是BlockEvent.TransactionEvent event = txFuture.get(); 行使应用程序处于无限期等待状态，即使在事务提交到账本之后也是如此。为什么会这样？

一旦我强制退出并运行 query() 方法，它就会列出资产。

Answer 1

我遇到了与此类似的问题，网上的许多答案都缺少代码的关键部分——将 EventHub 分配给频道。我在初始化通道之前添加了这个（在本例中将在 createChannel 方法中），然后我的交易被成功处理：

    channel.addEventHub(client.newEventHub("eventhub0", "grpc://localhost:7053"));