我的目标是创建一个可以由REST端点调用的同步过程。在我的实际需求中，这将处理来自Web界面的用户编辑，而异步管道则由设置为单独服务的相同进程组成，以处理通过事件流发送的数据。我们希望HTTP调用是同步的，以便在整个过程中进行编辑后即可立即显示结果。
就下面的示例而言，我有一个源，一个进程和一个接收器。我想使用Spring Cloud Stream的AggregateApplicationBuilder使用RestController作为源创建流程的聚合，但是下面的示例仅创建应用程序，并在完全连接好后立即将其关闭。
是否可以通过这种方式使用AggregateApplicationBuilder？我一直无法弄清楚如何使生成的AggregateApplication作为Web应用程序运行。
应用程序类：
package com.example.aggregate;
import com.example.aggregate.controller.FooController;
import com.example.aggregate.processor.BarProcess;
import com.example.aggregate.sink.SinkService;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.stream.aggregate.AggregateApplicationBuilder;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
new AggregateApplicationBuilder()
.web(true)
.from(FooController.class)
.via(BarProcess.class)
.to(SinkService.class)
.run(args);
}
}
作为来源的控制器：
package com.example.aggregate.controller;
import com.example.aggregate.dto.Foo;
import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.messaging.Source;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHeaders;
import org.springframework.messaging.support.MessageBuilder;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.time.Instant;
import java.util.HashMap;
@RestController
@RequestMapping("/v1/foo")
@EnableBinding(Source.class)
public class FooController {
private Source source;
public FooController(Source source) {
this.source = source;
}
@PostMapping
public void handleRequest(@RequestBody Foo foo) {
foo.putValue("Received", Instant.now().toString());
sendMessage(foo);
}
private void sendMessage(Foo foo) {
Message<Foo> message = MessageBuilder.createMessage(foo, new MessageHeaders(new HashMap<>()));
source.output().send(message);
}
}
处理器：
package com.example.aggregate.processor;
import com.example.aggregate.dto.Foo;
import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.annotation.StreamListener;
import org.springframework.cloud.stream.messaging.Processor;
import org.springframework.messaging.Message;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.messaging.support.MessageBuilder;
@EnableBinding(Processor.class)
public class BarProcess {
@StreamListener(Processor.INPUT)
@SendTo(Processor.OUTPUT)
public Message<Foo> doFoo(Message<Foo> message) {
Foo foo = message.getPayload();
foo.putValue("BarProcess", "completed");
return MessageBuilder.createMessage(foo, message.getHeaders());
}
}
接收器类（目前，我只是尝试将结果记录到System.out中）：
package com.example.aggregate.sink;
import com.example.aggregate.dto.Foo;
import org.springframework.cloud.stream.annotation.EnableBinding;
import org.springframework.cloud.stream.annotation.StreamListener;
import org.springframework.cloud.stream.messaging.Sink;
import org.springframework.messaging.Message;
import org.springframework.stereotype.Service;
@Service
@EnableBinding(Sink.class)
public class SinkService {
@StreamListener(Sink.INPUT)
public void processPayload(Message<Foo> payload) {
System.out.println("*****SINK*****");
System.out.println("Received: " + payload);
}
}
最后是简单的Foo类：
package com.example.aggregate.dto;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonInclude;
import java.util.HashMap;
import java.util.Map;
@JsonInclude(JsonInclude.Include.NON_NULL)
@JsonIgnoreProperties(ignoreUnknown = true)
public class Foo {
private Map<String, String> values;
public void putValue(String key, String value) {
if (values == null)
values = new HashMap<>();
values.put(key, value);
}
public Map<String, String> getValues() {
return values;
}
}
运行Spring应用程序时的输出是：
2018-12-18 18:12:00.104 INFO 94095 --- [ main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@1bd4fdd: startup date [Tue Dec 18 18:12:00 PST 2018]; root of context hierarchy
2018-12-18 18:12:00.301 INFO 94095 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'configurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$a4218ca6] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.0.2.RELEASE)
2018-12-18 18:12:00.398 INFO 94095 --- [ main] c.e.aggregate.SyncPipelineApplication : The following profiles are active: local
2018-12-18 18:12:00.408 INFO 94095 --- [ main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10: startup date [Tue Dec 18 18:12:00 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@1bd4fdd
2018-12-18 18:12:00.475 INFO 94095 --- [ main] o.s.i.config.IntegrationRegistrar : No bean named 'integrationHeaderChannelRegistry' has been explicitly defined. Therefore, a default DefaultHeaderChannelRegistry will be created.
2018-12-18 18:12:00.519 INFO 94095 --- [ main] faultConfiguringBeanFactoryPostProcessor : No bean named 'errorChannel' has been explicitly defined. Therefore, a default PublishSubscribeChannel will be created.
2018-12-18 18:12:00.521 INFO 94095 --- [ main] faultConfiguringBeanFactoryPostProcessor : No bean named 'taskScheduler' has been explicitly defined. Therefore, a default ThreadPoolTaskScheduler will be created.
2018-12-18 18:12:00.705 INFO 94095 --- [ main] o.s.s.c.ThreadPoolTaskScheduler : Initializing ExecutorService 'taskScheduler'
2018-12-18 18:12:00.864 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase -2147482648
2018-12-18 18:12:00.864 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase 0
2018-12-18 18:12:00.864 INFO 94095 --- [ main] o.s.i.endpoint.EventDrivenConsumer : Adding {logging-channel-adapter:_org.springframework.integration.errorLogger} as a subscriber to the 'errorChannel' channel
2018-12-18 18:12:00.864 INFO 94095 --- [ main] o.s.i.channel.PublishSubscribeChannel : Channel 'application-1.errorChannel' has 1 subscriber(s).
2018-12-18 18:12:00.864 INFO 94095 --- [ main] o.s.i.endpoint.EventDrivenConsumer : started _org.springframework.integration.errorLogger
2018-12-18 18:12:00.865 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase 2147482647
2018-12-18 18:12:00.869 INFO 94095 --- [ main] c.e.aggregate.SyncPipelineApplication : Started SyncPipelineApplication in 1.089 seconds (JVM running for 1.438)
2018-12-18 18:12:00.891 INFO 94095 --- [ main] com.example.aggregate.sink.SinkService : The following profiles are active: local
2018-12-18 18:12:00.893 INFO 94095 --- [ main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@54227100: startup date [Tue Dec 18 18:12:00 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.024 INFO 94095 --- [ main] o.s.integration.channel.DirectChannel : Channel 'application-1-1.input' has 1 subscriber(s).
2018-12-18 18:12:01.024 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase -2147482648
2018-12-18 18:12:01.024 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase 2147482647
2018-12-18 18:12:01.027 INFO 94095 --- [ main] com.example.aggregate.sink.SinkService : Started SinkService in 0.153 seconds (JVM running for 1.596)
2018-12-18 18:12:01.044 INFO 94095 --- [ main] c.e.aggregate.processor.BarProcess : The following profiles are active: local
2018-12-18 18:12:01.046 INFO 94095 --- [ main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@35fe2125: startup date [Tue Dec 18 18:12:01 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.143 INFO 94095 --- [ main] o.s.integration.channel.DirectChannel : Channel 'application-1-2.input' has 1 subscriber(s).
2018-12-18 18:12:01.144 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase -2147482648
2018-12-18 18:12:01.144 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase 2147482647
2018-12-18 18:12:01.145 INFO 94095 --- [ main] c.e.aggregate.processor.BarProcess : Started BarProcess in 0.116 seconds (JVM running for 1.714)
2018-12-18 18:12:01.158 INFO 94095 --- [ main] c.e.aggregate.controller.FooController : The following profiles are active: local
2018-12-18 18:12:01.162 INFO 94095 --- [ main] s.c.a.AnnotationConfigApplicationContext : Refreshing org.springframework.context.annotation.AnnotationConfigApplicationContext@48c40605: startup date [Tue Dec 18 18:12:01 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.244 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase -2147482648
2018-12-18 18:12:01.244 INFO 94095 --- [ main] o.s.c.support.DefaultLifecycleProcessor : Starting beans in phase 2147482647
2018-12-18 18:12:01.246 INFO 94095 --- [ main] c.e.aggregate.controller.FooController : Started FooController in 0.1 seconds (JVM running for 1.815)
2018-12-18 18:12:01.247 INFO 94095 --- [ Thread-5] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10: startup date [Tue Dec 18 18:12:00 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@1bd4fdd
2018-12-18 18:12:01.248 INFO 94095 --- [ Thread-5] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@54227100: startup date [Tue Dec 18 18:12:00 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.248 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 2147482647
2018-12-18 18:12:01.249 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase -2147482648
2018-12-18 18:12:01.249 INFO 94095 --- [ Thread-5] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@35fe2125: startup date [Tue Dec 18 18:12:01 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.250 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 2147482647
2018-12-18 18:12:01.250 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase -2147482648
2018-12-18 18:12:01.250 INFO 94095 --- [ Thread-5] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@48c40605: startup date [Tue Dec 18 18:12:01 PST 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@6a57ae10
2018-12-18 18:12:01.250 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 2147482647
2018-12-18 18:12:01.250 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase -2147482648
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 2147482647
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 0
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.i.endpoint.EventDrivenConsumer : Removing {logging-channel-adapter:_org.springframework.integration.errorLogger} as a subscriber to the 'errorChannel' channel
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.i.channel.PublishSubscribeChannel : Channel 'application-1.errorChannel' has 0 subscriber(s).
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.i.endpoint.EventDrivenConsumer : stopped _org.springframework.integration.errorLogger
2018-12-18 18:12:01.251 INFO 94095 --- [ Thread-5] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase -2147482648
2018-12-18 18:12:01.252 INFO 94095 --- [ Thread-5] o.s.s.c.ThreadPoolTaskScheduler : Shutting down ExecutorService 'taskScheduler'
Process finished with exit code 0
有关如何保持应用程序运行的任何指导？当我用一个使用InboundChannelAdapter的控制器源替换控制器源时，它会按照我期望的方式工作，并根据轮询时间发送消息。
提前谢谢
答案 0 :(得分：2)
David，虽然我们尚未真正宣布任何正式声明，但AggregatorBuilder实际上已被弃用;）我们不再赘述，您可能会注意到，最新的快照文档不再提供有关此部分的内容。
这意味着我们可以通过功能组合来更好，更简单地满足您的需求。目前，我们正在博客上发布Spring Cloud Stream的2.1.0.RELEASE版本，该版本将于1月初发布（我们现在位于RC4中），因此首先您需要切换到使用最新版本版本。
现在，支持是通过在Spring Cloud Stream中添加Spring Cloud Function编程模型来实现的。您可以详细了解here。 另外，不久前在此论坛上也提出了类似的问题，因此this link应该为您提供所需的答案。实际上，它引用了GitHub上使用Http源的示例应用程序，本质上展示了一个相同的情况。
请仔细阅读，如果您仍有任何问题，请告诉我们。
干杯， 奥列格（Oleg）