#2673: feat: Microservice pattern: Polling publisher #3243 (#3292)

* added new microservice pattern polling-publisher, created folder structure, README.md & App.java

* added two service polling service & publisher service to handle two different operation & prepared initial skeleton

* polling-publisher service implementation

* fixed checkstyle errors

* subscriber-service implementation

* added entry point for subscriber service & unit test-case

* added unit test-case for DataSourceService class

* resolved dependency & structured classes

* implemented Data repository, DataSource Service & added unittest-case & implemented polling-service microservice

* implemented subscriber microservice using kafkaConsumer

* Fixed Kafka bug & added a controller to send message using API

* Fixed subscriber-service & updated pom.xml

* Fixed topic name

* added new listener for other topic

* updated all README.md

* added description on both application.yaml file

* added scope before class definition in Test classes & removed duplicate dependency from pom.xml & added required one

* added polling-publisher module in pom.xml

* Updated README.md file based on new template

* improved the README.md file & fixed it's format

* deleted unnecessary README.md files

* fixed the printing statements & used log function

* used logger to print statement

* addressed review comment: removed unnecessary dependency

* addressed review comment

polling-publisher/pom.xml

@@ -0,0 +1,106 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+    This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
+
+    The MIT License
+    Copyright © 2014-2022 Ilkka Seppälä
+
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+
+-->
+<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>
+    <parent>
+      <groupId>com.iluwatar</groupId>
+      <artifactId>java-design-patterns</artifactId>
+      <version>1.26.0-SNAPSHOT</version>
+    </parent>
+
+    <artifactId>polling-publisher</artifactId>
+    <packaging>pom</packaging>
+
+    <modules>
+        <module>polling-service</module>
+        <module>subscriber-service</module>
+    </modules>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
+
+        <!-- Spring Boot Test -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <version>${spring-boot.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <!-- https://mvnrepository.com/artifact/org.springframework.kafka/spring-kafka -->
+        <dependency>
+            <groupId>org.springframework.kafka</groupId>
+            <artifactId>spring-kafka</artifactId>
+            <version>3.3.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.springframework.kafka</groupId>
+            <artifactId>spring-kafka-test</artifactId>
+            <version>3.3.2</version>
+            <scope>test</scope>
+        </dependency>
+
+        <!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot -->
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
+
+        <!-- https://mvnrepository.com/artifact/javax.annotation/javax.annotation-api -->
+        <dependency>
+            <groupId>javax.annotation</groupId>
+            <artifactId>javax.annotation-api</artifactId>
+            <version>1.3.2</version>
+        </dependency>
+
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-core</artifactId>
+            <version>1.5.18</version>
+        </dependency>
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <version>1.5.18</version>
+        </dependency>
+
+    </dependencies>
+
+</project>