Java 将所有事件从CommandGateway路由到单个事件处理程序
我用AxonFramework实现JGroups,我指的是链接。我在代码中做了一些更改,并在没有Docker的情况下运行项目。下面是我的代码- 主类- 主节点-Java 将所有事件从CommandGateway路由到单个事件处理程序,java,cqrs,jgroups,axon,Java,Cqrs,Jgroups,Axon,我用AxonFramework实现JGroups,我指的是链接。我在代码中做了一些更改,并在没有Docker的情况下运行项目。下面是我的代码- 主类- 主节点- 现在我的问题是,当我运行main类时,主节点产生5个事件,而次节点并没有获得所有事件。它可能有2个、3个或4个事件,但不是全部。我希望所有事件都传递到辅助节点。我对AxonFramework和JGroup非常陌生。请帮助我理解这里的问题所在。所以在尝试了所有方法后,我决定尝试路由策略。我决定使用AbstractRoutingStrate
现在我的问题是,当我运行main类时,主节点产生5个事件,而次节点并没有获得所有事件。它可能有2个、3个或4个事件,但不是全部。我希望所有事件都传递到辅助节点。我对AxonFramework和JGroup非常陌生。请帮助我理解这里的问题所在。所以在尝试了所有方法后,我决定尝试路由策略。我决定使用AbstractRoutingStrategy,这基本上有助于对没有决定性目的地的命令消息进行决策。以下是JGroup的主节点发送器中的工作代码。将PrimaryNode类中的configureDistributedCommandBus方法修改为-
private CommandBus configureDistributedCommandBus() throws Exception {
CommandBus commandBus = new SimpleCommandBus();
channel = new JChannel(getClass().getClassLoader().getResourceAsStream("tcp.xml"));
RoutingStrategy rs = new AbstractRoutingStrategy(UnresolvedRoutingKeyPolicy.STATIC_KEY) {
@Override
protected String doResolveRoutingKey(CommandMessage<?> cmdMsg) {
View view = channel.getView();
if (view.getMembers().size() == 2) {
return "secondary";
} else if (view.getMembers().size() == 1) {
}
return cmdMsg.getIdentifier();
}
};
connector = new JGroupsConnector(commandBus, channel, "axon-jgroups-demo", new XStreamSerializer(), rs);
connector.updateMembership(100, AcceptAll.INSTANCE);
connector.connect();
connector.awaitJoined();
return new DistributedCommandBus(connector, connector);
}
因为我使用的是JGroups,所以我可以获得集群的视图,即有多少个节点。在此基础上,我将决定命令消息的路由。默认情况下,Axon会将每个事件处理程序订阅到事件总线(在您的案例中为EmbeddedEventStore)。这意味着在特定本地实例发布事件时调用处理程序。处理命令时会发布该事件。因此,本质上,事件处理程序是在处理命令的节点上调用的 或者,您可以将事件处理程序配置为在跟踪模式下运行。在这种情况下,它们将打开与事件存储的连接。在这种情况下,根据具体的配置,每个节点都可以获取自己的事件副本,而不管它发布在何处
import org.axonframework.commandhandling.AggregateAnnotationCommandHandler;
import org.axonframework.commandhandling.CommandBus;
import org.axonframework.commandhandling.SimpleCommandBus;
import org.axonframework.commandhandling.distributed.AnnotationRoutingStrategy;
import org.axonframework.commandhandling.distributed.DistributedCommandBus;
import org.axonframework.commandhandling.distributed.commandfilter.AcceptAll;
import org.axonframework.commandhandling.gateway.CommandGateway;
import org.axonframework.commandhandling.gateway.DefaultCommandGateway;
import org.axonframework.commandhandling.model.Repository;
import org.axonframework.eventsourcing.EventSourcingRepository;
import org.axonframework.eventsourcing.eventstore.EmbeddedEventStore;
import org.axonframework.eventsourcing.eventstore.EventStore;
import org.axonframework.eventsourcing.eventstore.inmemory.InMemoryEventStorageEngine;
import org.axonframework.jgroups.commandhandling.JGroupsConnector;
import org.axonframework.serialization.xml.XStreamSerializer;
import org.jgroups.JChannel;
public class PrimaryNode implements Runnable {
private JGroupsConnector connector;
private CommandGateway commandGateway;
private EventStore eventStore;
private CommandBus commandBus;
public PrimaryNode() {
eventStore = new EmbeddedEventStore(new InMemoryEventStorageEngine());
try {
commandBus = configureDistributedCommandBus();
} catch (Exception e) {
e.printStackTrace();
}
Repository<Item> repository = new EventSourcingRepository<>(Item.class, eventStore);
new AggregateAnnotationCommandHandler<>(Item.class, repository).subscribe(commandBus);
commandGateway = new DefaultCommandGateway(commandBus);
}
public void run() {
for (int a = 0; a < 5; a++) {
System.out.println("Primary Node Created item " + a + " id: " + System.currentTimeMillis());
commandGateway.sendAndWait(new CreateItem(Long.toString(a), Long.toString(System.currentTimeMillis())));
}
}
private CommandBus configureDistributedCommandBus() throws Exception {
CommandBus commandBus = new SimpleCommandBus();
JChannel channel = new JChannel(getClass().getClassLoader().getResourceAsStream("tcp.xml"));
connector = new JGroupsConnector(commandBus, channel, "axon-jgroups-demo", new XStreamSerializer(),
new AnnotationRoutingStrategy());
connector.updateMembership(100, AcceptAll.INSTANCE);
connector.connect();
connector.awaitJoined();
return new DistributedCommandBus(connector, connector);
}
}
import org.axonframework.commandhandling.AggregateAnnotationCommandHandler;
import org.axonframework.commandhandling.CommandBus;
import org.axonframework.commandhandling.SimpleCommandBus;
import org.axonframework.commandhandling.distributed.AnnotationRoutingStrategy;
import org.axonframework.commandhandling.distributed.DistributedCommandBus;
import org.axonframework.commandhandling.distributed.commandfilter.AcceptAll;
import org.axonframework.commandhandling.gateway.CommandGateway;
import org.axonframework.commandhandling.gateway.DefaultCommandGateway;
import org.axonframework.commandhandling.model.Repository;
import org.axonframework.eventhandling.EventListener;
import org.axonframework.eventhandling.SimpleEventHandlerInvoker;
import org.axonframework.eventhandling.SubscribingEventProcessor;
import org.axonframework.eventsourcing.EventSourcingRepository;
import org.axonframework.eventsourcing.eventstore.EmbeddedEventStore;
import org.axonframework.eventsourcing.eventstore.EventStore;
import org.axonframework.eventsourcing.eventstore.inmemory.InMemoryEventStorageEngine;
import org.axonframework.jgroups.commandhandling.JGroupsConnector;
import org.axonframework.serialization.xml.XStreamSerializer;
import org.jgroups.JChannel;
public class SecondaryNode implements Runnable {
private JGroupsConnector connector;
private EventStore eventStore;
public SecondaryNode() {
eventStore = new EmbeddedEventStore(new InMemoryEventStorageEngine());
CommandBus commandBus = null;
try {
commandBus = configureDistributedCommandBus();
} catch (Exception e) {
e.printStackTrace();
}
Repository<Item> repository = new EventSourcingRepository<>(Item.class, eventStore);
new AggregateAnnotationCommandHandler<>(Item.class, repository).subscribe(commandBus);
@SuppressWarnings("unused")
CommandGateway commandGateway = new DefaultCommandGateway(commandBus);
}
public void run() {
new SubscribingEventProcessor("processor", new SimpleEventHandlerInvoker((EventListener) event -> {
System.out.println("Secondary Node -- " + event.getPayload());
}), eventStore).start();
}
private CommandBus configureDistributedCommandBus() throws Exception {
CommandBus commandBus = new SimpleCommandBus();
JChannel channel = new JChannel(getClass().getClassLoader().getResourceAsStream("tcp_test.xml"));
connector = new JGroupsConnector(commandBus, channel, "axon-jgroups-demo", new XStreamSerializer(),
new AnnotationRoutingStrategy());
connector.updateMembership(100, AcceptAll.INSTANCE);
connector.connect();
connector.awaitJoined();
return new DistributedCommandBus(connector, connector);
}
}
import org.axonframework.commandhandling.CommandHandler;
import org.axonframework.commandhandling.TargetAggregateIdentifier;
import org.axonframework.commandhandling.model.AggregateIdentifier;
import org.axonframework.eventhandling.EventHandler;
import static org.axonframework.commandhandling.model.AggregateLifecycle.apply;
class CreateItem {
@TargetAggregateIdentifier
private final String itemId;
private final String name;
public CreateItem(String itemId, String naam) {
this.itemId = itemId;
this.name = naam;
}
public String getItemId() {
return itemId;
}
public String getName() {
return name;
}
}
class ItemCreated {
private final String itemId;
private final String name;
public ItemCreated(String itemId, String naam) {
this.itemId = itemId;
this.name = naam;
}
public String getItemId() {
return itemId;
}
public String getName() {
return name;
}
@Override
public String toString() {
return itemId + " " + name;
}
}
class Item {
@AggregateIdentifier
private String itemId;
private String name;
public Item() {
}
@CommandHandler
public Item(CreateItem createItem) {
apply(new ItemCreated(createItem.getItemId(), createItem.getName()));
}
@EventHandler
public void itemCreated(ItemCreated itemCreated) {
itemId = itemCreated.getItemId();
name = itemCreated.getName();
}
}
private CommandBus configureDistributedCommandBus() throws Exception {
CommandBus commandBus = new SimpleCommandBus();
channel = new JChannel(getClass().getClassLoader().getResourceAsStream("tcp.xml"));
RoutingStrategy rs = new AbstractRoutingStrategy(UnresolvedRoutingKeyPolicy.STATIC_KEY) {
@Override
protected String doResolveRoutingKey(CommandMessage<?> cmdMsg) {
View view = channel.getView();
if (view.getMembers().size() == 2) {
return "secondary";
} else if (view.getMembers().size() == 1) {
}
return cmdMsg.getIdentifier();
}
};
connector = new JGroupsConnector(commandBus, channel, "axon-jgroups-demo", new XStreamSerializer(), rs);
connector.updateMembership(100, AcceptAll.INSTANCE);
connector.connect();
connector.awaitJoined();
return new DistributedCommandBus(connector, connector);
}