Spring Integration channel adapter code samples

pom.xml

@@ -89,6 +89,7 @@
         <module>pubsub/cloud-client</module>
         <module>spanner/cloud-client</module>
         <module>speech/cloud-client</module>
+        <module>spring/integration/pubsub</module>
         <module>storage/cloud-client</module>
         <module>storage/json-api</module>
         <module>storage/storage-transfer</module>

spring/integration/pubsub/pom.xml

@@ -0,0 +1,120 @@
+<?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">
+  <parent>
+    <artifactId>doc-samples</artifactId>
+    <groupId>com.google.cloud</groupId>
+    <version>1.0.0</version>
+    <relativePath>../../..</relativePath>
+  </parent>
+  <modelVersion>4.0.0</modelVersion>
+  <packaging>jar</packaging>
+
+  <artifactId>spring-integration-pubsub-samples</artifactId>
+
+  <properties>
+    <spring-cloud-gcp.version>1.0.0.BUILD-SNAPSHOT</spring-cloud-gcp.version>
+    <spring-boot.version>1.5.2.RELEASE</spring-boot.version>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.springframework.cloud</groupId>
+      <artifactId>spring-cloud-gcp-starter-pubsub</artifactId>
+      <version>${spring-cloud-gcp.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.cloud</groupId>
+      <artifactId>spring-integration-gcp</artifactId>
+      <version>${spring-cloud-gcp.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>org.springframework.boot</groupId>
+      <artifactId>spring-boot-starter-web</artifactId>
+      <version>${spring-boot.version}</version>
+    </dependency>
+  </dependencies>
+
+  <!-- Angular -->
+
+  <build>
+    <resources>
+      <resource>
+        <directory>src/main/resources</directory>
+      </resource>
+      <resource>
+        <directory>${project.build.directory}/generated-resources</directory>
+      </resource>
+    </resources>
+    <plugins>
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+        <version>1.5.2.RELEASE</version>
+      </plugin>
+      <plugin>
+        <artifactId>maven-resources-plugin</artifactId>
+        <version>3.0.1</version>
+        <executions>
+          <execution>
+            <!-- Serves *only* to filter the wro.xml so it can get an absolute
+              path for the project -->
+            <id>copy-resources</id>
+            <phase>validate</phase>
+            <goals>
+              <goal>copy-resources</goal>
+            </goals>
+            <configuration>
+              <outputDirectory>${basedir}/target/wro</outputDirectory>
+              <resources>
+                <resource>
+                  <directory>src/main/wro</directory>
+                  <filtering>true</filtering>
+                </resource>
+              </resources>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>ro.isdc.wro4j</groupId>
+        <artifactId>wro4j-maven-plugin</artifactId>
+        <version>1.7.6</version>
+        <executions>
+          <execution>
+            <phase>generate-resources</phase>
+            <goals>
+              <goal>run</goal>
+            </goals>
+          </execution>
+        </executions>
+        <configuration>
+          <wroManagerFactory>ro.isdc.wro.maven.plugin.manager.factory.ConfigurableWroManagerFactory</wroManagerFactory>
+          <cssDestinationFolder>${project.build.directory}/generated-resources/static/css</cssDestinationFolder>
+          <jsDestinationFolder>${project.build.directory}/generated-resources/static/js</jsDestinationFolder>
+          <wroFile>${project.build.directory}/wro/wro.xml</wroFile>
+          <extraConfigFile>src/main/wro/wro.properties</extraConfigFile>
+          <contextFolder>${basedir}/src/main/wro</contextFolder>
+        </configuration>
+        <dependencies>
+          <dependency>
+            <groupId>org.webjars</groupId>
+            <artifactId>jquery</artifactId>
+            <version>2.1.1</version>
+          </dependency>
+          <dependency>
+            <groupId>org.webjars</groupId>
+            <artifactId>angularjs</artifactId>
+            <version>1.3.8</version>
+          </dependency>
+          <dependency>
+            <groupId>org.webjars</groupId>
+            <artifactId>bootstrap</artifactId>
+            <version>3.2.0</version>
+          </dependency>
+        </dependencies>
+      </plugin>
+    </plugins>
+  </build>
+</project>

spring/integration/pubsub/src/main/java/com/example/spring/pubsub/PubsubApplication.java

@@ -0,0 +1,153 @@
+package com.example.spring.pubsub;
+
+import com.google.pubsub.v1.Subscription;
+import com.google.pubsub.v1.SubscriptionName;
+import com.google.pubsub.v1.Topic;
+import com.google.pubsub.v1.TopicName;
+import java.io.IOException;
+
+import com.google.cloud.pubsub.v1.AckReplyConsumer;
+import com.google.protobuf.ByteString;
+
+import java.util.List;
+import java.util.stream.Collectors;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.cloud.gcp.pubsub.PubsubAdmin;
+import org.springframework.cloud.gcp.pubsub.core.PubsubTemplate;
+import org.springframework.cloud.gcp.pubsub.support.GcpHeaders;
+import org.springframework.cloud.gcp.pubsub.support.SubscriberFactory;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.integration.annotation.IntegrationComponentScan;
+import org.springframework.integration.annotation.MessagingGateway;
+import org.springframework.integration.annotation.ServiceActivator;
+import org.springframework.integration.channel.PublishSubscribeChannel;
+import org.springframework.integration.gcp.AckMode;
+import org.springframework.integration.gcp.inbound.PubsubInboundChannelAdapter;
+import org.springframework.integration.gcp.outbound.PubsubMessageHandler;
+import org.springframework.messaging.MessageChannel;
+import org.springframework.messaging.MessageHandler;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.servlet.view.RedirectView;
+
+@SpringBootApplication
+@IntegrationComponentScan
+@RestController
+@ComponentScan(basePackages = {"org.springframework.cloud.gcp"})
+public class PubsubApplication {
+
+  private static final Log LOGGER = LogFactory.getLog(PubsubApplication.class);
+
+  @Autowired
+  private PubsubOutboundGateway messagingGateway;
+
+  @Autowired
+  private PubsubAdmin admin;
+
+  public static void main(String[] args) throws IOException {
+    SpringApplication.run(PubsubApplication.class, args);
+  }
+
+  @GetMapping("/listTopics")
+  public List<String> listTopics() {
+    return admin.listTopics().stream()
+        .map(Topic::getNameAsTopicName)
+        .map(TopicName::getTopic)
+        .collect(Collectors.toList());
+  }
+
+  @GetMapping("/listSubscriptions")
+  public List<String> listSubscriptions() {
+    return admin.listSubscriptions().stream()
+        .map(Subscription::getNameAsSubscriptionName)
+        .map(SubscriptionName::getSubscription)
+        .collect(Collectors.toList());
+  }
+
+  @PostMapping("/postMessage")
+  public RedirectView addMessage(@RequestParam("message") String message) {
+    messagingGateway.sendToPubsub(message);
+    return new RedirectView("/");
+  }
+
+  @PostMapping("/newTopic")
+  public RedirectView newTopic(@RequestParam("name") String topicName) {
+    admin.createTopic(topicName);
+    return new RedirectView("/");
+  }
+
+  @PostMapping("/newSubscription")
+  public RedirectView newSubscription(@RequestParam("name") String subscriptionName,
+      @RequestParam("topic") String topicName) {
+    admin.createSubscription(subscriptionName, topicName);
+    return new RedirectView("/");
+  }
+
+  @Bean
+  public MessageChannel pubsubInputChannel() {
+    return new PublishSubscribeChannel();
+  }
+
+  @Bean
+  public PubsubInboundChannelAdapter messageChannelAdapter(
+      @Qualifier("pubsubInputChannel") MessageChannel inputChannel,
+      SubscriberFactory subscriberFactory) {
+    PubsubInboundChannelAdapter adapter =
+        new PubsubInboundChannelAdapter(subscriberFactory, "messages");
+    adapter.setOutputChannel(inputChannel);
+    adapter.setAckMode(AckMode.MANUAL);
+
+    return adapter;
+  }
+
+  @Bean
+  @ServiceActivator(inputChannel = "pubsubInputChannel")
+  public MessageHandler receiveMessage() {
+    return message -> {
+      LOGGER.info("Message arrived! Payload: "
+          + ((ByteString) message.getPayload()).toStringUtf8());
+      AckReplyConsumer consumer = (AckReplyConsumer) message.getHeaders().get(
+          GcpHeaders.ACKNOWLEDGEMENT);
+      consumer.ack();
+    };
+  }
+
+  @Bean
+  @ServiceActivator(inputChannel = "pubsubInputChannel")
+  public MessageHandler receiveMessageInParallel() {
+    return message -> {
+      LOGGER.info("Message also arrived here! Payload: "
+          + ((ByteString) message.getPayload()).toStringUtf8());
+      AckReplyConsumer consumer = (AckReplyConsumer) message.getHeaders().get(
+          GcpHeaders.ACKNOWLEDGEMENT);
+      consumer.ack();
+    };
+  }
+
+  @Bean
+  @ServiceActivator(inputChannel = "pubsubOutputChannel")
+  public MessageHandler messageSender(PubsubTemplate pubsubTemplate) throws IOException {
+    PubsubMessageHandler outboundAdapter = new PubsubMessageHandler(pubsubTemplate);
+    outboundAdapter.setTopic("test");
+    return outboundAdapter;
+  }
+
+  @Bean
+  public MessageChannel pubsubOutputChannel() {
+    return new PublishSubscribeChannel();
+  }
+
+  @MessagingGateway(defaultRequestChannel = "pubsubOutputChannel")
+  public interface PubsubOutboundGateway {
+
+    void sendToPubsub(String text);
+  }
+}

spring/integration/pubsub/src/main/resources/static/index.html

@@ -0,0 +1,36 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="UTF-8">
+  <title>Spring Integration GCP sample</title>
+  <link href="css/angular-bootstrap.css" rel="stylesheet">
+  <script src="js/angular-bootstrap.js" type="text/javascript"></script>
+  <script src="js/pubsub.js"></script>
+</head>
+<body ng-app="pubsub">
+<div name="formDiv">
+  <form action="/postMessage" method="post">
+    Post message: <input type="text" name="message" /> <input type="submit" />
+  </form>
+  <form action="/newTopic" method="post">
+    New topic: <input type="text" name="name" /> <input type="submit" />
+  </form>
+  <form action="/newSubscription" method="post">
+    New subscription: <input type="text" name="name" />
+    for topic <input type="text" name="topic" /> <input type="submit" />
+  </form>
+</div>
+<div ng-controller="listTopics">
+  <h1>Topics</h1>
+  <div ng-repeat="topic in topics">
+    {{ topic }}<br/>
+  </div>
+</div>
+<div ng-controller="listSubscriptions">
+  <h1>Subscriptions</h1>
+  <div ng-repeat="subscription in subscriptions">
+    {{ subscription }}<br/>
+  </div>
+</div>
+</body>
+</html>

spring/integration/pubsub/src/main/resources/static/js/pubsub.js

@@ -0,0 +1,11 @@
+angular.module('pubsub', [])
+    .controller('listTopics', function($scope, $http) {
+      $http.get('/listTopics').success(function(data) {
+        $scope.topics = data;
+      });
+    })
+    .controller('listSubscriptions', function($scope, $http) {
+      $http.get('/listSubscriptions').success(function(data) {
+        $scope.subscriptions = data;
+      })
+    });

spring/integration/pubsub/src/main/wro/wro.properties

@@ -0,0 +1,4 @@
+#List of preProcessors
+preProcessors=lessCssImport
+#List of postProcessors
+postProcessors=less4j,jsMin

spring/integration/pubsub/src/main/wro/wro.xml

@@ -0,0 +1,9 @@
+<groups xmlns="http://www.isdc.ro/wro">
+  <group name="angular-bootstrap">
+    <css>webjar:bootstrap/3.2.0/less/bootstrap.less</css>
+    <css>file:${project.basedir}/src/main/wro/main.less</css>
+    <js>webjar:jquery/2.1.1/jquery.min.js</js>
+    <js>webjar:bootstrap/3.2.0/bootstrap.js</js>
+    <js>webjar:angularjs/1.3.8/angular.min.js</js>
+  </group>
+</groups>