Kafka Initial producer App code.

KafkaProducerApp/pom.xml

+<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.2.4.RELEASE</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.kafka.producer</groupId>
+	<artifactId>KafkaProducerApp</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>KafkaProducerApp</name>
+	<description>Voter Producer App</description>
+
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>com.common.models</groupId>
+			<artifactId>CommonBeanPojo</artifactId>
+			<version>0.0.1-SNAPSHOT</version>
+		</dependency>
+		<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
+		<dependency>
+			<groupId>com.fasterxml.jackson.core</groupId>
+			<artifactId>jackson-databind</artifactId>
+		</dependency>
+
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

KafkaProducerApp/src/main/java/com/kafka/producer/KafkaProducerAppApplication.java

+package com.kafka.producer;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class KafkaProducerAppApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(KafkaProducerAppApplication.class, args);
+	}
+
+}

KafkaProducerApp/src/main/java/com/kafka/producer/config/KakfaConfiguration.java

+package com.kafka.producer.config;
+
+import org.apache.kafka.clients.producer.ProducerConfig;
+import org.apache.kafka.common.serialization.StringSerializer;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.kafka.core.DefaultKafkaProducerFactory;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.kafka.core.ProducerFactory;
+import org.springframework.kafka.support.serializer.JsonSerializer;
+
+import com.common.pojos.User;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@Configuration
+public class KakfaConfiguration {
+
+    @Bean
+    public ProducerFactory<String, User> producerFactory() {
+        Map<String, Object> config = new HashMap<>();
+
+        config.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "127.0.0.1:9092");
+        config.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
+        config.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, JsonSerializer.class);
+
+        return new DefaultKafkaProducerFactory<>(config);
+    }
+
+
+    @Bean
+    public KafkaTemplate<String, User> kafkaTemplate() {
+        return new KafkaTemplate<>(producerFactory());
+    }
+
+
+}

KafkaProducerApp/src/main/java/com/kafka/producer/resource/UserResource.java

+package com.kafka.producer.resource;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.PropertySource;
+import org.springframework.kafka.core.KafkaTemplate;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestMethod;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.common.pojos.User;
+
+/**
+ * Kafka Controller used to produce the User data to the consumer application.
+ * @author rjosula
+ *
+ */
+@RestController
+@RequestMapping("kafka")
+@PropertySource("appConfig.properties")
+public class UserResource {
+
+    @Autowired
+    private KafkaTemplate<String, User> kafkaTemplate;
+
+    @Value("${kafka.producer.topic.name}")
+    private String TOPIC;
+
+    @RequestMapping(value = "/publish", method = RequestMethod.POST)
+    public User post(@RequestBody User user) {
+
+        kafkaTemplate.send(TOPIC, user);
+
+        return user;
+    }
+}

KafkaProducerApp/src/main/resources/appConfig.properties

+kafka.producer.topic.name=Kafka_User_topic
\ No newline at end of file

KafkaProducerApp/src/main/resources/application.properties

+server.port=8080
\ No newline at end of file