Merge pull request #67 from NashTech-Labs/feature/Added-shipment_test…

…_cases

Added test cases and ReadMe file for shipment service

shipment-service/README.md

@@ -0,0 +1,43 @@
+## Shipment Service
+
+#### Application Overview
+This application is designed to manage the shipment process in a system using the Axon Framework for CQRS (Command Query Responsibility Segregation) and Event Sourcing. It includes components for handling the creation of shipments, persisting shipment details in a database, and publishing events to a Google Cloud Pub/Sub topic.
+
+## Workflow
+
+### Shipment Creation:
+* The process begins with a CreateShipmentCommand, which is handled by the ShipmentAggregate class. 
+* The aggregate processes the command, applies the ShipmentCreatedEvent, and triggers the OrderShippedEvent.
+
+### Event Handling:
+* The ShipmentCreatedEvent is handled by the ShipmentEventHandler.
+* The event handler extracts user information and shipment details from the event.
+* It saves the shipment details to a database using the ShipmentRepository.
+* Additionally, it uses the PubSubPublisherService to publish the shipment details to a Google Cloud Pub/Sub topic.
+
+### Google Cloud Pub/Sub Integration:
+* The PubSubPublisherService initializes the Pub/Sub publisher during application startup (@PostConstruct).
+* The publisher is responsible for converting shipment data into a Pub/Sub message and publishing it to the configured topic.
+* During application shutdown (@PreDestroy), the publisher is gracefully shut down.
+
+### Data Storage:
+* Shipment details, including user information, are persisted to a database for future reference.
+* The ShipmentRepository handles the database interactions.
+
+## Key Components
+
+### ShipmentAggregate:
+
+Manages the state and behavior related to the creation of shipments.
+Applies events to update its internal state.
+
+### ShipmentEventHandler:
+Listens for the ShipmentCreatedEvent.
+    Extracts shipment and user details from the event.
+    Saves shipment details to a database using the ShipmentRepository.
+    Publishes shipment details to Google Cloud Pub/Sub using the PubSubPublisherService.
+
+### PubSubPublisherService:
+Initializes a Google Cloud Pub/Sub publisher during application startup.
+    Publishes shipment data to a Pub/Sub topic.
+    Gracefully shuts down the publisher during application shutdown.

shipment-service/pom.xml

@@ -60,6 +60,13 @@
 			<artifactId>spring-boot-starter-test</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<!-- https://mvnrepository.com/artifact/org.axonframework/axon-test -->
+		<dependency>
+			<groupId>org.axonframework</groupId>
+			<artifactId>axon-test</artifactId>
+			<version>4.8.0</version>
+			<scope>test</scope>
+		</dependency>
 
 		<dependency>
 			<groupId>com.google.cloud</groupId>

shipment-service/src/main/java/com/nashtech/shipment/aggregate/ShipmentAggregate.java

@@ -4,6 +4,7 @@
 import com.nashtech.common.event.OrderShippedEvent;
 import com.nashtech.common.event.ShipmentCreatedEvent;
 import com.nashtech.common.model.User;
+import lombok.Getter;
 import lombok.extern.slf4j.Slf4j;
 import org.axonframework.commandhandling.CommandHandler;
 import org.axonframework.eventsourcing.EventSourcingHandler;
@@ -13,6 +14,7 @@
 
 @Aggregate
 @Slf4j
+@Getter
 public class ShipmentAggregate {
 
     @AggregateIdentifier

shipment-service/src/main/java/com/nashtech/shipment/service/PubSubPublisherService.java

@@ -9,8 +9,6 @@
 import com.google.pubsub.v1.TopicName;
 import com.nashtech.shipment.config.GCPConfig;
 import com.nashtech.shipment.entity.ShipmentEntity;
-import jakarta.annotation.PostConstruct;
-import jakarta.annotation.PreDestroy;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
@@ -26,15 +24,23 @@ public class PubSubPublisherService {
     private GCPConfig gcpConfig;
     private ObjectMapper objectMapper;
 
-    @PostConstruct
+    public PubSubPublisherService(GCPConfig gcpConfig, Publisher publisher) {
+        this.gcpConfig = gcpConfig;
+        TopicName topicName = TopicName.of(gcpConfig.getProjectId(), gcpConfig.getTopicId());
+        objectMapper = new ObjectMapper();
+        objectMapper.enable(SerializationFeature.INDENT_OUTPUT);
+        this.publisher = publisher;
+    }
+
     public void init() throws IOException {
         TopicName topicName = TopicName.of(gcpConfig.getProjectId(), gcpConfig.getTopicId());
-        publisher = Publisher.newBuilder(topicName).build();
         objectMapper = new ObjectMapper();
         objectMapper.enable(SerializationFeature.INDENT_OUTPUT);
+        if (publisher == null) {
+            publisher = Publisher.newBuilder(topicName).build();
+        }
     }
 
-    @PreDestroy
     public void cleanup() {
         try {
             if (publisher != null) {
@@ -52,12 +58,15 @@ public void messagePublisher(final ShipmentEntity shipmentEntity) {
         log.info("Publishing data to topic: {}", gcpConfig.getTopicId());
 
         try {
+            init();
             String shipmentData = objectMapper.writeValueAsString(shipmentEntity);
             PubsubMessage pubsubMessage = PubsubMessage.newBuilder().setData(ByteString.copyFromUtf8(shipmentData)).build();
             ApiFuture<String> publishedMessage = publisher.publish(pubsubMessage);
             log.info("Message id generated:{}", publishedMessage.get());
         } catch (Exception exception) {
             log.error("Error : {} while publishing data to pub sub topic : {}", exception.getMessage(), gcpConfig.getTopicId());
+        } finally {
+            cleanup();
         }
     }
 

shipment-service/src/test/java/com/nashtech/shipment/aggregate/ShipmentAggregateTest.java

@@ -0,0 +1,209 @@
+package com.nashtech.shipment.aggregate;
+
+import com.nashtech.common.command.CreateShipmentCommand;
+import com.nashtech.common.event.OrderShippedEvent;
+import com.nashtech.common.event.ShipmentCreatedEvent;
+import com.nashtech.shipment.util.ObjectCreator;
+import com.nashtech.shipment.util.TestTag;
+import org.axonframework.test.aggregate.AggregateTestFixture;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@Tag(TestTag.SMALL_TESTS)
+class ShipmentAggregateTest {
+    private AggregateTestFixture<ShipmentAggregate> fixture;
+
+    @BeforeEach
+    void setUp() {
+        fixture = new AggregateTestFixture<>(ShipmentAggregate.class);
+    }
+
+    @Test
+    void testShipmentAggregateCreation() {
+
+        CreateShipmentCommand createShipmentCommand = ObjectCreator.getShipmentCommand();
+
+        ShipmentCreatedEvent shipmentCreatedEvent = ObjectCreator.getShipmentCreatedEvent();
+
+        OrderShippedEvent shippedEvent = ObjectCreator.getOrderShippedEvent();
+
+        fixture.givenNoPriorActivity()
+                .when(createShipmentCommand)
+                .expectEvents(shipmentCreatedEvent, shippedEvent);
+    }
+
+
+    @Test
+    void test_shipment_created_event_handling_with_null_values() {
+        ShipmentAggregate shipmentAggregate = new ShipmentAggregate();
+        ShipmentCreatedEvent shipmentCreatedEvent = ShipmentCreatedEvent.builder().build();
+
+        shipmentAggregate.on(shipmentCreatedEvent);
+
+        assertNull(shipmentAggregate.getShipmentId());
+        assertNull(shipmentAggregate.getOrderId());
+        assertNull(shipmentAggregate.getPaymentId());
+        assertNull(shipmentAggregate.getProductId());
+        assertNull(shipmentAggregate.getBrand());
+        assertNull(shipmentAggregate.getQuantity());
+        assertNull(shipmentAggregate.getBasePrice());
+        assertNull(shipmentAggregate.getSubTotal());
+        assertNull(shipmentAggregate.getTotal());
+        assertNull(shipmentAggregate.getTax());
+        assertNull(shipmentAggregate.getTotalTax());
+        assertNull(shipmentAggregate.getUser());
+    }
+
+    @Test
+    void test_shipment_aggregate_state_update() {
+
+        ShipmentCreatedEvent shipmentCreatedEvent = ShipmentCreatedEvent.builder()
+                .shipmentId("shipmentId")
+                .orderId("orderId")
+                .paymentId("paymentId")
+                .productId("productId")
+                .quantity(10)
+                .brand("brand")
+                .basePrice(100.0)
+                .tax(0.1f)
+                .totalTax(10.0f)
+                .subTotal(1000.0)
+                .total(1100.0)
+                .user(ObjectCreator.getUser())
+                .build();
+        ShipmentAggregate shipmentAggregate = new ShipmentAggregate();
+        shipmentAggregate.on(shipmentCreatedEvent);
+        assertEquals(shipmentCreatedEvent.getShipmentId(), shipmentAggregate.getShipmentId());
+        assertEquals(shipmentCreatedEvent.getOrderId(), shipmentAggregate.getOrderId());
+        assertEquals(shipmentCreatedEvent.getPaymentId(), shipmentAggregate.getPaymentId());
+        assertEquals(shipmentCreatedEvent.getProductId(), shipmentAggregate.getProductId());
+        assertEquals(shipmentCreatedEvent.getQuantity(), shipmentAggregate.getQuantity());
+        assertEquals(shipmentCreatedEvent.getBrand(), shipmentAggregate.getBrand());
+        assertEquals(shipmentCreatedEvent.getBasePrice(), shipmentAggregate.getBasePrice());
+        assertEquals(shipmentCreatedEvent.getTax(), shipmentAggregate.getTax());
+        assertEquals(shipmentCreatedEvent.getTotalTax(), shipmentAggregate.getTotalTax());
+        assertEquals(shipmentCreatedEvent.getSubTotal(), shipmentAggregate.getSubTotal());
+        assertEquals(shipmentCreatedEvent.getTotal(), shipmentAggregate.getTotal());
+        assertEquals(shipmentCreatedEvent.getUser(), shipmentAggregate.getUser());
+    }
+
+    @Test
+    void testShipmentCreatedEventHandling() {
+
+        ShipmentAggregate shipmentAggregate = new ShipmentAggregate();
+        ShipmentCreatedEvent shipmentCreatedEvent = ObjectCreator.getShipmentCreatedEvent();
+        shipmentAggregate.on(shipmentCreatedEvent);
+        assertEquals(shipmentCreatedEvent.getShipmentId(), shipmentAggregate.getShipmentId());
+        assertEquals(shipmentCreatedEvent.getOrderId(), shipmentAggregate.getOrderId());
+        assertEquals(shipmentCreatedEvent.getPaymentId(), shipmentAggregate.getPaymentId());
+        assertEquals(shipmentCreatedEvent.getProductId(), shipmentAggregate.getProductId());
+        assertEquals(shipmentCreatedEvent.getBrand(), shipmentAggregate.getBrand());
+        assertEquals(shipmentCreatedEvent.getQuantity(), shipmentAggregate.getQuantity());
+        assertEquals(shipmentCreatedEvent.getBasePrice(), shipmentAggregate.getBasePrice());
+        assertEquals(shipmentCreatedEvent.getSubTotal(), shipmentAggregate.getSubTotal());
+        assertEquals(shipmentCreatedEvent.getTotal(), shipmentAggregate.getTotal());
+        assertEquals(shipmentCreatedEvent.getTax(), shipmentAggregate.getTax());
+        assertEquals(shipmentCreatedEvent.getTotalTax(), shipmentAggregate.getTotalTax());
+        assertEquals(shipmentCreatedEvent.getUser(), shipmentAggregate.getUser());
+    }
+
+    @Test
+    void test_negative_totalTax_throws_exception() {
+        CreateShipmentCommand createShipmentCommand = CreateShipmentCommand.builder()
+                .shipmentId("shipmentId")
+                .orderId("orderId")
+                .paymentId("paymentId")
+                .productId("productId")
+                .quantity(10)
+                .brand("brand")
+                .basePrice(100.0)
+                .tax(0.1f)
+                .totalTax(-10.0f)
+                .subTotal(1000.0)
+                .total(1100.0)
+                .user(ObjectCreator.getUser())
+                .build();
+
+        assertThrows(IllegalStateException.class, () -> {
+            new ShipmentAggregate(createShipmentCommand);
+        });
+    }
+
+
+    @Test
+    void testShipmentCreatedEventHandlingWithNullValues() {
+
+        ShipmentAggregate shipmentAggregate = new ShipmentAggregate();
+        ShipmentCreatedEvent shipmentCreatedEvent = ShipmentCreatedEvent.builder().build();
+
+        shipmentAggregate.on(shipmentCreatedEvent);
+
+        assertNull(shipmentAggregate.getShipmentId());
+        assertNull(shipmentAggregate.getOrderId());
+        assertNull(shipmentAggregate.getPaymentId());
+        assertNull(shipmentAggregate.getProductId());
+        assertNull(shipmentAggregate.getBrand());
+        assertNull(shipmentAggregate.getQuantity());
+        assertNull(shipmentAggregate.getBasePrice());
+        assertNull(shipmentAggregate.getSubTotal());
+        assertNull(shipmentAggregate.getTotal());
+        assertNull(shipmentAggregate.getTax());
+        assertNull(shipmentAggregate.getTotalTax());
+        assertNull(shipmentAggregate.getUser());
+    }
+
+    @Test
+    void test_instantiation_success() {
+        ShipmentAggregate shipmentAggregate = new ShipmentAggregate();
+        assertNotNull(shipmentAggregate);
+    }
+
+
+    @Test
+    void testShipmentAggregateConstructorWithNullShipmentId() {
+        CreateShipmentCommand createShipmentCommand = CreateShipmentCommand.builder()
+                .shipmentId(null)
+                .orderId("orderId")
+                .paymentId("paymentId")
+                .productId("productId")
+                .quantity(10)
+                .brand("brand")
+                .basePrice(100.0)
+                .tax(0.1f)
+                .totalTax(10.0f)
+                .subTotal(1000.0)
+                .total(1100.0)
+                .user(ObjectCreator.getUser())
+                .build();
+
+        assertThrows(IllegalStateException.class, () -> {
+            new ShipmentAggregate(createShipmentCommand);
+        });
+    }
+
+    @Test
+    void testShipmentAggregateConstructorWithInvalidTotalCalculation() {
+        CreateShipmentCommand createShipmentCommand = CreateShipmentCommand.builder()
+                .shipmentId("shipmentId")
+                .orderId("orderId")
+                .paymentId("paymentId")
+                .productId("productId")
+                .quantity(-1) // Invalid quantity
+                .brand("brand")
+                .basePrice(100.0)
+                .tax(0.1f)
+                .totalTax(10.0f)
+                .subTotal(1000.0)
+                .total(1100.0)
+                .user(ObjectCreator.getUser())
+                .build();
+
+        assertThrows(IllegalStateException.class, () -> {
+            new ShipmentAggregate(createShipmentCommand);
+        });
+    }
+
+}

shipment-service/src/test/java/com/nashtech/shipment/handler/ShipmentEventHandlerTest.java

@@ -0,0 +1,37 @@
+package com.nashtech.shipment.handler;
+
+import com.nashtech.common.event.ShipmentCreatedEvent;
+import com.nashtech.shipment.entity.ShipmentEntity;
+import com.nashtech.shipment.repository.ShipmentRepository;
+import com.nashtech.shipment.service.PubSubPublisherService;
+import com.nashtech.shipment.util.ObjectCreator;
+import com.nashtech.shipment.util.TestTag;
+import org.junit.jupiter.api.Tag;
+import org.junit.jupiter.api.Test;
+import org.mockito.Mockito;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.times;
+
+@Tag(TestTag.SMALL_TESTS)
+class ShipmentEventHandlerTest {
+
+    @Test
+    void testShipmentEventHandler() {
+
+        ShipmentRepository mockShipmentRepository = Mockito.mock(ShipmentRepository.class);
+        PubSubPublisherService mockPubSubPublisherService = Mockito.mock(PubSubPublisherService.class);
+
+        ShipmentEventHandler shipmentEventHandler = new ShipmentEventHandler(mockShipmentRepository, mockPubSubPublisherService);
+
+        ShipmentCreatedEvent shipmentCreatedEvent = ObjectCreator.getShipmentCreatedEvent();
+
+
+        shipmentEventHandler.on(shipmentCreatedEvent);
+
+
+        Mockito.verify(mockShipmentRepository, times(1)).save(any(ShipmentEntity.class));
+        Mockito.verify(mockPubSubPublisherService, times(1)).messagePublisher(any(ShipmentEntity.class));
+    }
+
+}