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

Author: quantdevv

Diff for: polling-publisher/polling-service/src/main/java/com/iluwatar/polling/DataRepository.java

@@ -25,12 +25,54 @@
 
 package com.iluwatar.polling;
 
+import java.util.HashMap;
+import java.util.Map;
 import org.springframework.stereotype.Repository;
+import javax.annotation.PostConstruct;
+
 
 /**
  * Data repository to keep or store data.
- * */
+ */
 @Repository
 public final class DataRepository {
-  // Simulate a repository for data access
-}
+
+  private final Map<Integer, String> dataStorage = new HashMap<>();
+
+  @PostConstruct
+  public void init() {
+    // Injecting dummy data at startup
+    dataStorage.put(2, "Initial Dummy Data - two - 2");
+    dataStorage.put(3, "Initial Dummy Data - three - 3");
+    dataStorage.put(4, "Initial Dummy Data - four - 4");
+  }
+
+
+  /**
+   * Save data to the repository.
+   */
+  public void save(int id, String value) {
+    dataStorage.put(id, value);
+  }
+
+  /**
+   * Retrieve data by ID.
+   */
+  public String findById(int id) {
+    return dataStorage.getOrDefault(id, "Data not found");
+  }
+
+  /**
+   * Delete data by ID.
+   */
+  public void delete(int id) {
+    dataStorage.remove(id);
+  }
+
+  /**
+   * Get all data.
+   */
+  public Map<Integer, String> findAll() {
+    return dataStorage;
+  }
+}

Diff for: polling-publisher/polling-service/src/main/java/com/iluwatar/polling/DataSourceService.java

@@ -26,6 +26,8 @@
 package com.iluwatar.polling;
 
 import java.util.List;
+import java.util.Map;
+import java.util.Random;
 import org.springframework.stereotype.Service;
 
 /**
@@ -34,11 +36,43 @@
 @Service
 public class DataSourceService {
 
-  /**
-   * Function to fetch data from DataRepository.
-   * */
-  public String fetchData() {
-    // Simulate fetching data from a data source
-    return "Sample Data " + System.currentTimeMillis();
+  private final DataRepository repository;
+
+  public DataSourceService(DataRepository repository) {
+    this.repository = repository;
+
+    // Start a separate thread to add data every 3 seconds
+    new Thread(() -> {
+      Random random = new Random();
+      while (true) {
+        try {
+          Thread.sleep(3000); // Add data every 3 seconds
+          int id = random.nextInt(100); // Random ID
+          String value = "Auto-Data-" + id;
+          this.addData(id, value);
+          System.out.println("🔵 Data Added: " + id + " -> " + value);
+        } catch (InterruptedException e) {
+          Thread.currentThread().interrupt();
+          break;
+        }
+      }
+    }).start();
+
+  }
+
+  public void addData(int id, String value) {
+    repository.save(id, value);
+  }
+
+  public String getData(int id) {
+    return repository.findById(id);
+  }
+
+  public void removeData(int id) {
+    repository.delete(id);
+  }
+
+  public Map<Integer, String> getAllData() {
+    return repository.findAll();
   }
 }

Diff for: polling-publisher/polling-service/src/main/java/com/iluwatar/polling/PollingScheduler.java

@@ -28,6 +28,7 @@
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.scheduling.annotation.Scheduled;
 import org.springframework.stereotype.Component;
+import java.util.Random;
 
 /**
  * This class is responsible for scheduling polling tasks.
@@ -42,13 +43,18 @@ public class PollingScheduler {
   private KafkaProducer kafkaProducer;
 
   /**
-   * schedular for poll data on each 5 second.
+   * Scheduler for poll data on each 5 second.
    * */
   @Scheduled(fixedRate = 5000) // Poll every 5 seconds
   public void pollDataSource() {
-    String data = dataSourceService.fetchData();
+    int id = new Random().nextInt(100); // Pick a random ID
+    String data = dataSourceService.getData(id); // Get data from service
+
     if (data != null) {
+      System.out.println("🟢 Publishing Data: " + data);
       kafkaProducer.sendMessage(data);
+    } else {
+      System.out.println("🔴 No Data Found for ID: " + id);
     }
   }
 }

Diff for: polling-publisher/polling-service/src/main/resources/application.yml

@@ -0,0 +1,29 @@
+#
+# The MIT License
+# Copyright © 2014-2021 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.
+#
+
+server:
+    port: 8081
+spring:
+    kafka:
+        consumer:
+            group-id: subscriber-group

Diff for: polling-publisher/polling-service/src/test/java/com/iluwatar/polling/AppTest.java

@@ -25,11 +25,15 @@
 package com.iluwatar.polling;
 
 import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
 
-public class AppTest {
+import static org.junit.jupiter.api.Assertions.*;
+
+@SpringBootTest
+class AppTest {
 
   @Test
-  public void polling() {
-    System.out.println(".(checking.. code is not running)");
+  void polling() {
+    assertDoesNotThrow(() -> App.main(new String[]{}));
   }
 }

Diff for: polling-publisher/polling-service/src/test/java/com/iluwatar/polling/DataRepositoryTest.java

@@ -0,0 +1,79 @@
+/*
+ * 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.
+ */
+package com.iluwatar.polling;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import java.util.Map;
+
+class DataRepositoryTest {
+
+  private DataRepository repository;
+
+  @BeforeEach
+  void setUp() {
+    repository = new DataRepository(); // Initialize before each test
+  }
+
+  @Test
+  void testSaveAndFindById() {
+    repository.save(1, "Test Data");
+
+    String result = repository.findById(1);
+
+    assertEquals("Test Data", result, "The retrieved data should match the stored value.");
+  }
+
+  @Test
+  void testFindById_NotFound() {
+    String result = repository.findById(99);
+
+    assertEquals("Data not found", result, "Should return 'Data not found' for missing entries.");
+  }
+
+  @Test
+  void testDelete() {
+    repository.save(2, "To be deleted");
+    repository.delete(2);
+
+    String result = repository.findById(2);
+
+    assertEquals("Data not found", result, "Deleted data should not be retrievable.");
+  }
+
+  @Test
+  void testFindAll() {
+    repository.save(1, "First");
+    repository.save(2, "Second");
+
+    Map<Integer, String> allData = repository.findAll();
+
+    assertEquals(2, allData.size(), "The repository should contain two items.");
+    assertTrue(allData.containsKey(1) && allData.containsKey(2), "Both keys should exist.");
+  }
+}

Diff for: polling-publisher/polling-service/src/test/java/com/iluwatar/polling/DataSourceServiceTest.java

@@ -25,18 +25,57 @@
 
 package com.iluwatar.polling;
 
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.*;
+import java.util.Map;
 
-/*
- * this class contains the unit test for DataSoourceServiceTest class.
- */
-public class DataSourceServiceTest {
+import static org.junit.jupiter.api.Assertions.*;
+
+class DataSourceServiceTest {
+
+  private DataRepository repository;
+  private DataSourceService service;
+
+  @BeforeEach
+  void setUp() {
+    repository = new DataRepository();
+    service = new DataSourceService(repository);
+  }
+
+  @Test
+  void testAddData() {
+    service.addData(1, "Test Data");
+
+    assertEquals("Test Data", repository.findById(1));
+  }
+
+  @Test
+  void testGetData() {
+    repository.save(1, "Test Data");
+
+    String result = service.getData(1);
 
-  DataSourceService dataSourceService = new DataSourceService();
+    assertEquals("Test Data", result, "The retrieved data should match.");
+  }
 
   @Test
-  public void test1() {
-    System.out.println(".(checking.. code is running)");
+  void testRemoveData() {
+    repository.save(2, "Some Data");
+
+    service.removeData(2);
+
+    assertEquals("Data not found", repository.findById(2), "Deleted data should not be retrievable.");
+
+  }
+
+  @Test
+  void testGetAllData() {
+    repository.save(1, "First");
+    repository.save(2, "Second");
+
+    Map<Integer, String> result = service.getAllData();
+
+    assertEquals(2, result.size(), "Should return all stored data.");
+    assertEquals("First", result.get(1), "Value for key 1 should be 'First'.");
+    assertEquals("Second", result.get(2), "Value for key 2 should be 'Second'.");
   }
 }