Add StreamListener Usage Sample
This resolves #8 Doc updates Address review comments
This commit is contained in:
Ilayaperumal Gopinathan
committed by
Gary Russell
Gary Russell
parent
78a5e4f5d9
commit
2414a2f1ef
1
pom.xml
1
pom.xml
@@ -26,6 +26,7 @@
|
||||
<module>multibinder-differentsystems</module>
|
||||
<module>rxjava-processor</module>
|
||||
<module>multi-io</module>
|
||||
<module>stream-listener</module>
|
||||
</modules>
|
||||
<dependencyManagement>
|
||||
<dependencies>
|
||||
|
||||
42
stream-listener/README.md
Normal file
42
stream-listener/README.md
Normal file
@@ -0,0 +1,42 @@
|
||||
Spring Cloud Stream Stream Listener Sample
|
||||
=============================
|
||||
|
||||
In this *Spring Cloud Stream* sample, the application shows how to use StreamListener support to enable message mapping and automatic type conversion.
|
||||
|
||||
## Requirements
|
||||
|
||||
To run this sample, you will need to have installed:
|
||||
|
||||
* Java 8 or Above
|
||||
|
||||
This example requires Redis to be running on localhost.
|
||||
|
||||
## Code Tour
|
||||
|
||||
This sample is a Spring Boot application that bundles multiple application together to showcase how to use StreamListener to enable
|
||||
message mapping and automatic type conversion.
|
||||
|
||||
* TypeConversionApplication - the Spring Boot Main Application
|
||||
* Converters - the class that holds the required custom message converter that converts POJO of type `Foo` to `Bar`
|
||||
* SampleSource - the app that generates a message of type `Foo` that has the value `hi`
|
||||
* SampleTransformer - the app that has the message handler method annotated with @StreamListener to map the process input channel to a type `Bar`.
|
||||
This will make sure to apply `FooToBarConverter` automatically without having a need to specify `content-type` for the channel explicitly.
|
||||
The annotation @SendTo on the message handler method will make sure to send the output to the provided output channel.
|
||||
* SampleSink - the app that receives the converted message from the transformer output.
|
||||
|
||||
Please note that the applications (SampleSource, SampleTransformer and SampleSink) are bundled inside the single application for the demo
|
||||
purpose only. In practice, these applications run on their own. If at all they need to be bundled together, the best practice is to use
|
||||
`AggregateApplicationBuilder`. Refer the sample `double` for more info on aggregate application.
|
||||
|
||||
## Building with Maven
|
||||
|
||||
Build the sample by executing:
|
||||
|
||||
>$ mvn clean package
|
||||
|
||||
## Running the Sample
|
||||
|
||||
To start the source module execute the following:
|
||||
|
||||
>$ java -jar target/spring-cloud-stream-sample-stream-listener-1.0.0.BUILD-SNAPSHOT-exec.jar
|
||||
|
||||
59
stream-listener/pom.xml
Normal file
59
stream-listener/pom.xml
Normal file
@@ -0,0 +1,59 @@
|
||||
<?xml version="1.0" encoding="UTF-8"?>
|
||||
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
|
||||
<modelVersion>4.0.0</modelVersion>
|
||||
|
||||
<artifactId>spring-cloud-stream-sample-stream-listener</artifactId>
|
||||
<packaging>jar</packaging>
|
||||
|
||||
<name>spring-cloud-stream-sample-stream-listener</name>
|
||||
<description>Demo project for stream listener</description>
|
||||
|
||||
<parent>
|
||||
<groupId>org.springframework.cloud</groupId>
|
||||
<artifactId>spring-cloud-stream-samples</artifactId>
|
||||
<version>1.0.0.BUILD-SNAPSHOT</version>
|
||||
</parent>
|
||||
|
||||
<properties>
|
||||
<start-class>demo.TypeConversionApplication</start-class>
|
||||
</properties>
|
||||
|
||||
<dependencies>
|
||||
<dependency>
|
||||
<groupId>org.springframework.cloud</groupId>
|
||||
<artifactId>spring-cloud-stream</artifactId>
|
||||
</dependency>
|
||||
<dependency>
|
||||
<groupId>org.springframework.cloud</groupId>
|
||||
<artifactId>spring-cloud-stream-binder-redis</artifactId>
|
||||
</dependency>
|
||||
<dependency>
|
||||
<groupId>org.springframework.boot</groupId>
|
||||
<artifactId>spring-boot-starter-redis</artifactId>
|
||||
</dependency>
|
||||
<dependency>
|
||||
<groupId>org.springframework.boot</groupId>
|
||||
<artifactId>spring-boot-configuration-processor</artifactId>
|
||||
<optional>true</optional>
|
||||
</dependency>
|
||||
|
||||
<dependency>
|
||||
<groupId>org.springframework.boot</groupId>
|
||||
<artifactId>spring-boot-starter-test</artifactId>
|
||||
<scope>test</scope>
|
||||
</dependency>
|
||||
</dependencies>
|
||||
|
||||
<build>
|
||||
<plugins>
|
||||
<plugin>
|
||||
<groupId>org.springframework.boot</groupId>
|
||||
<artifactId>spring-boot-maven-plugin</artifactId>
|
||||
<configuration>
|
||||
<classifier>exec</classifier>
|
||||
</configuration>
|
||||
</plugin>
|
||||
</plugins>
|
||||
</build>
|
||||
|
||||
</project>
|
||||
101
stream-listener/src/main/java/demo/Converters.java
Normal file
101
stream-listener/src/main/java/demo/Converters.java
Normal file
@@ -0,0 +1,101 @@
|
||||
/*
|
||||
* Copyright 2016 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
import org.springframework.cloud.stream.converter.AbstractFromMessageConverter;
|
||||
import org.springframework.context.annotation.Bean;
|
||||
import org.springframework.context.annotation.Configuration;
|
||||
import org.springframework.messaging.Message;
|
||||
import org.springframework.messaging.converter.MessageConversionException;
|
||||
import org.springframework.util.MimeType;
|
||||
|
||||
/**
|
||||
* @author Ilayaperumal Gopinathan
|
||||
*/
|
||||
@Configuration
|
||||
public class Converters {
|
||||
|
||||
//Register custom converter
|
||||
@Bean
|
||||
public AbstractFromMessageConverter fooConverter() {
|
||||
return new FooToBarConverter();
|
||||
}
|
||||
|
||||
public static class Foo {
|
||||
|
||||
private String value = "foo";
|
||||
|
||||
public String getValue() {
|
||||
return this.value;
|
||||
}
|
||||
|
||||
public void setValue(String value) {
|
||||
this.value = value;
|
||||
}
|
||||
}
|
||||
|
||||
public static class Bar {
|
||||
|
||||
private String value = "init";
|
||||
|
||||
public Bar(String value) {
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
public String getValue() {
|
||||
return this.value;
|
||||
}
|
||||
|
||||
public void setValue(String value) {
|
||||
this.value = value;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
public static class FooToBarConverter extends AbstractFromMessageConverter {
|
||||
|
||||
public FooToBarConverter() {
|
||||
super(MimeType.valueOf("test/bar"));
|
||||
}
|
||||
|
||||
@Override
|
||||
protected Class<?>[] supportedTargetTypes() {
|
||||
return new Class[] {Bar.class};
|
||||
}
|
||||
|
||||
@Override
|
||||
protected Class<?>[] supportedPayloadTypes() {
|
||||
return new Class<?>[] {Foo.class};
|
||||
}
|
||||
|
||||
@Override
|
||||
public Object convertFromInternal(Message<?> message, Class<?> targetClass, Object conversionHint) {
|
||||
Object result = null;
|
||||
try {
|
||||
if (message.getPayload() instanceof Foo) {
|
||||
Foo fooPayload = (Foo) message.getPayload();
|
||||
result = new Bar(fooPayload.getValue());
|
||||
}
|
||||
}
|
||||
catch (Exception e) {
|
||||
logger.error(e.getMessage(), e);
|
||||
throw new MessageConversionException(e.getMessage());
|
||||
}
|
||||
return result;
|
||||
}
|
||||
}
|
||||
}
|
||||
45
stream-listener/src/main/java/demo/SampleSink.java
Normal file
45
stream-listener/src/main/java/demo/SampleSink.java
Normal file
@@ -0,0 +1,45 @@
|
||||
/*
|
||||
* Copyright 2015 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
import org.springframework.cloud.stream.annotation.EnableBinding;
|
||||
import org.springframework.cloud.stream.annotation.Input;
|
||||
import org.springframework.cloud.stream.annotation.StreamListener;
|
||||
import org.springframework.messaging.SubscribableChannel;
|
||||
|
||||
/**
|
||||
* @author Ilayaperumal Gopinathan
|
||||
*/
|
||||
@EnableBinding(SampleSink.Sink.class)
|
||||
public class SampleSink {
|
||||
|
||||
// Sink application definition
|
||||
@StreamListener(Sink.SAMPLE)
|
||||
public void receive(Converters.Bar barMessage) {
|
||||
System.out.println("******************");
|
||||
System.out.println("At the Sink");
|
||||
System.out.println("******************");
|
||||
System.out.println("Received transformed message " + barMessage.getValue() + " of type " + barMessage.getClass());
|
||||
}
|
||||
|
||||
public interface Sink {
|
||||
String SAMPLE = "sample-sink";
|
||||
|
||||
@Input(SAMPLE)
|
||||
SubscribableChannel sampleSink();
|
||||
}
|
||||
}
|
||||
57
stream-listener/src/main/java/demo/SampleSource.java
Normal file
57
stream-listener/src/main/java/demo/SampleSource.java
Normal file
@@ -0,0 +1,57 @@
|
||||
/*
|
||||
* Copyright 2016 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
import org.springframework.cloud.stream.annotation.EnableBinding;
|
||||
import org.springframework.cloud.stream.annotation.Output;
|
||||
import org.springframework.context.annotation.Bean;
|
||||
import org.springframework.integration.annotation.InboundChannelAdapter;
|
||||
import org.springframework.integration.annotation.Poller;
|
||||
import org.springframework.integration.core.MessageSource;
|
||||
import org.springframework.messaging.Message;
|
||||
import org.springframework.messaging.MessageChannel;
|
||||
import org.springframework.messaging.support.GenericMessage;
|
||||
|
||||
/**
|
||||
* @author Ilayaperumal Gopinathan
|
||||
*/
|
||||
@EnableBinding(SampleSource.Source.class)
|
||||
public class SampleSource {
|
||||
|
||||
@Bean
|
||||
@InboundChannelAdapter(value = Source.SAMPLE, poller = @Poller(fixedDelay = "1000", maxMessagesPerPoll = "1"))
|
||||
public MessageSource<String> timerMessageSource() {
|
||||
return new MessageSource<String>() {
|
||||
public Message<String> receive() {
|
||||
System.out.println("******************");
|
||||
System.out.println("At the Source");
|
||||
System.out.println("******************");
|
||||
Converters.Foo foo = new Converters.Foo();
|
||||
foo.setValue("hi");
|
||||
System.out.println("Sending value: " + foo.getValue() + " of type " + foo.getClass());
|
||||
return new GenericMessage(foo);
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
public interface Source {
|
||||
String SAMPLE = "sample-source";
|
||||
|
||||
@Output(SAMPLE)
|
||||
MessageChannel sampleSource();
|
||||
}
|
||||
}
|
||||
45
stream-listener/src/main/java/demo/SampleTransformer.java
Normal file
45
stream-listener/src/main/java/demo/SampleTransformer.java
Normal file
@@ -0,0 +1,45 @@
|
||||
/*
|
||||
* Copyright 2015 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
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.handler.annotation.SendTo;
|
||||
|
||||
/**
|
||||
* @author Ilayaperumal Gopinathan
|
||||
*/
|
||||
@EnableBinding(Processor.class)
|
||||
public class SampleTransformer {
|
||||
|
||||
private static final String TRANSFORMATION_VALUE = "HI";
|
||||
|
||||
// Transformer application definition
|
||||
|
||||
@StreamListener(Processor.INPUT)
|
||||
@SendTo(Processor.OUTPUT)
|
||||
public Converters.Bar receive(Converters.Bar barMessage) {
|
||||
System.out.println("******************");
|
||||
System.out.println("At the transformer");
|
||||
System.out.println("******************");
|
||||
System.out.println("Received value "+ barMessage.getValue() + " of type " + barMessage.getClass());
|
||||
System.out.println("Transforming the value to " + TRANSFORMATION_VALUE + " and with the type " + barMessage.getClass());
|
||||
barMessage.setValue(TRANSFORMATION_VALUE);
|
||||
return barMessage;
|
||||
}
|
||||
}
|
||||
@@ -0,0 +1,29 @@
|
||||
/*
|
||||
* Copyright 2015 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
import org.springframework.boot.SpringApplication;
|
||||
import org.springframework.boot.autoconfigure.SpringBootApplication;
|
||||
|
||||
@SpringBootApplication
|
||||
public class TypeConversionApplication {
|
||||
|
||||
public static void main(String[] args) {
|
||||
SpringApplication.run(TypeConversionApplication.class, args);
|
||||
}
|
||||
|
||||
}
|
||||
14
stream-listener/src/main/resources/application.yml
Normal file
14
stream-listener/src/main/resources/application.yml
Normal file
@@ -0,0 +1,14 @@
|
||||
server:
|
||||
port: 8082
|
||||
spring:
|
||||
cloud:
|
||||
stream:
|
||||
bindings:
|
||||
sample-source:
|
||||
destination: testtock
|
||||
input:
|
||||
destination: testtock
|
||||
output:
|
||||
destination: xformed
|
||||
sample-sink:
|
||||
destination: xformed
|
||||
@@ -0,0 +1,36 @@
|
||||
/*
|
||||
* Copyright 2015 the original author or authors.
|
||||
*
|
||||
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||
* you may not use this file except in compliance with the License.
|
||||
* You may obtain a copy of the License at
|
||||
*
|
||||
* http://www.apache.org/licenses/LICENSE-2.0
|
||||
*
|
||||
* Unless required by applicable law or agreed to in writing, software
|
||||
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
* See the License for the specific language governing permissions and
|
||||
* limitations under the License.
|
||||
*/
|
||||
|
||||
package demo;
|
||||
|
||||
import org.junit.Test;
|
||||
import org.junit.runner.RunWith;
|
||||
import org.springframework.test.annotation.DirtiesContext;
|
||||
import org.springframework.test.context.web.WebAppConfiguration;
|
||||
import org.springframework.boot.test.SpringApplicationConfiguration;
|
||||
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
|
||||
|
||||
@RunWith(SpringJUnit4ClassRunner.class)
|
||||
@SpringApplicationConfiguration(classes = TypeConversionApplication.class)
|
||||
@WebAppConfiguration
|
||||
@DirtiesContext
|
||||
public class ModuleApplicationTests {
|
||||
|
||||
@Test
|
||||
public void contextLoads() {
|
||||
}
|
||||
|
||||
}
|
||||
Reference in New Issue
Block a user