>
+ +publish(topic, payload)
+ }
+
+ OrderService ..> Order : creates
+ OrderService ..> OutboxEvent : creates
+ OutboxPublisher ..> OutboxEvent : polls & updates
+ OutboxPublisher --> MessageBroker : dispatches
+```
+
+## When to Use the Transactional Outbox Pattern
+
+Use this pattern when:
+
+* You need to update a database and publish messages to an event broker without data loss or inconsistent dual-writes.
+* Distributed transactions (XA 2-phase commit) are not supported, perform poorly, or add unwanted complexity.
+* You are building event-driven microservices requiring **at-least-once** event delivery guarantees.
+
+## Real-World Applications
+
+* E-commerce checkout systems emitting order creation events for billing and fulfillment services.
+* Financial transaction processing services issuing audit log events alongside database updates.
+* Microservices using Change Data Capture (CDC) like Debezium for database log mining outbox patterns.
+
+## Benefits and Trade-offs
+
+### Benefits
+
+* **No Dual-Write Inconsistency**: Prevents lost messages or phantom events caused by network/broker outages.
+* **At-Least-Once Delivery**: Guarantees event delivery to message consumers.
+* **No Distributed Transactions**: Avoids expensive and fragile XA/2PC transactions across services.
+
+### Trade-Offs
+
+* **Near Real-time Latency**: Polling intervals add slight delay before events are dispatched.
+* **Duplicate Message Handling**: Consumers must implement idempotent processing to handle potential message redeliveries.
+* **Outbox Table Cleanup**: Outbox entries must be periodically archived or purged to prevent uncontrolled table growth.
+
+## Related Java Design Patterns
+
+* [Polling Publisher](https://java-design-patterns.com/patterns/polling-publisher/)
+* [Saga Pattern](https://java-design-patterns.com/patterns/saga/)
+* [Idempotent Consumer](https://java-design-patterns.com/patterns/microservices-idempotent-consumer/)
+* [Event-Driven Architecture](https://java-design-patterns.com/patterns/event-driven-architecture/)
+
+## References and Credits
+
+* [Microservices.io - Pattern: Transactional Outbox](https://microservices.io/patterns/data/transactional-outbox.html)
+* [Debezium - Reliable Microservices Data Exchange With the Outbox Pattern](https://debezium.io/blog/2019/02/19/reliable-microservices-data-exchange-with-outbox-pattern/)
+* [Designing Data-Intensive Applications - Martin Kleppmann](https://dataintensive.net/)
diff --git a/transactional-outbox/pom.xml b/transactional-outbox/pom.xml
new file mode 100644
index 000000000000..c8c178d60739
--- /dev/null
+++ b/transactional-outbox/pom.xml
@@ -0,0 +1,116 @@
+
+
+
+ 4.0.0
+
+ com.iluwatar
+ java-design-patterns
+ 1.26.0-SNAPSHOT
+
+
+ transactional-outbox
+
+
+
+
+ org.springframework.boot
+ spring-boot-starter-data-jpa
+
+
+
+
+ org.springframework.boot
+ spring-boot-starter-web
+
+
+
+
+ org.projectlombok
+ lombok
+ ${lombok.version}
+ provided
+
+
+
+
+ com.h2database
+ h2
+ runtime
+
+
+
+
+ org.springframework.boot
+ spring-boot-starter-test
+ test
+
+
+
+
+ org.junit.jupiter
+ junit-jupiter-engine
+ test
+
+
+
+
+ org.mockito
+ mockito-core
+ test
+
+
+
+
+
+
+ org.apache.maven.plugins
+ maven-assembly-plugin
+
+
+ package
+
+ single
+
+
+
+ jar-with-dependencies
+
+
+
+ com.iluwatar.transactionaloutbox.App
+
+
+
+
+
+
+
+
+
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/App.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/App.java
new file mode 100644
index 000000000000..65f851a7e7e7
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/App.java
@@ -0,0 +1,83 @@
+/*
+ * 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.transactionaloutbox;
+
+import lombok.RequiredArgsConstructor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.CommandLineRunner;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+/**
+ * Transactional Outbox Pattern Demonstration Application.
+ *
+ * The Transactional Outbox pattern ensures reliable event publishing in microservices by
+ * persisting events into a database outbox table within the same database transaction as the
+ * business entity update. A background polling process then dispatches pending outbox events to a
+ * message broker.
+ */
+@EnableScheduling
+@SpringBootApplication
+@RequiredArgsConstructor
+public class App implements CommandLineRunner {
+
+ private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
+
+ private final OrderService orderService;
+ private final OutboxPublisher outboxPublisher;
+ private final MessageConsumer messageConsumer;
+
+ /**
+ * Main entry point for the Spring Boot Application.
+ *
+ * @param args command-line arguments
+ */
+ public static void main(String[] args) {
+ SpringApplication.run(App.class, args);
+ }
+
+ @Override
+ public void run(String... args) {
+ LOGGER.info("Starting Transactional Outbox Pattern demonstration...");
+
+ // 1. Create order and outbox record in a single transaction
+ var order1 = orderService.createOrder("Alice", "Laptop", 1200.00);
+ var order2 = orderService.createOrder("Bob", "Headphones", 150.00);
+
+ LOGGER.info("Created orders with IDs: [{}], [{}]", order1.getId(), order2.getId());
+
+ // 2. Poll and publish outbox events to message broker
+ LOGGER.info("Triggering OutboxPublisher to process pending events...");
+ outboxPublisher.processOutboxEvents();
+
+ // 3. Inspect consumed events
+ LOGGER.info(
+ "Total messages consumed by MessageConsumer: {}",
+ messageConsumer.getConsumedMessages().size());
+ }
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/EventStatus.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/EventStatus.java
new file mode 100644
index 000000000000..df146f2e2a89
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/EventStatus.java
@@ -0,0 +1,33 @@
+/*
+ * 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.transactionaloutbox;
+
+/** Enum representing the status of an outbox event. */
+public enum EventStatus {
+ PENDING,
+ PROCESSED,
+ FAILED
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageBroker.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageBroker.java
new file mode 100644
index 000000000000..d37cc4b13f70
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageBroker.java
@@ -0,0 +1,38 @@
+/*
+ * 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.transactionaloutbox;
+
+/** Interface for message broker publishing. */
+public interface MessageBroker {
+
+ /**
+ * Publishes an event message to a topic/queue.
+ *
+ * @param topic destination topic name
+ * @param payload event message payload
+ */
+ void publish(String topic, String payload);
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageConsumer.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageConsumer.java
new file mode 100644
index 000000000000..fd0243d58aa9
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/MessageConsumer.java
@@ -0,0 +1,62 @@
+/*
+ * 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.transactionaloutbox;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+
+/** Message Consumer/Broker implementation demonstrating event receipt. */
+@Service
+public class MessageConsumer implements MessageBroker {
+
+ private static final Logger LOGGER = LoggerFactory.getLogger(MessageConsumer.class);
+
+ private final List consumedMessages = Collections.synchronizedList(new ArrayList<>());
+
+ @Override
+ public void publish(String topic, String payload) {
+ LOGGER.info("MessageBroker received message on topic [{}]: {}", topic, payload);
+ consumedMessages.add(payload);
+ }
+
+ /**
+ * Retrieves unmodifiable list of consumed messages.
+ *
+ * @return list of payloads received by the broker
+ */
+ public List getConsumedMessages() {
+ return Collections.unmodifiableList(consumedMessages);
+ }
+
+ /** Clears accumulated messages. */
+ public void clearMessages() {
+ consumedMessages.clear();
+ }
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/Order.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/Order.java
new file mode 100644
index 000000000000..b446a9f1f3f6
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/Order.java
@@ -0,0 +1,64 @@
+/*
+ * 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.transactionaloutbox;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.EnumType;
+import jakarta.persistence.Enumerated;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Table;
+import java.time.LocalDateTime;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+/** Represents a business Order entity persisted in the database. */
+@Entity
+@Table(name = "orders")
+@Data
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class Order {
+
+ @Id
+ @GeneratedValue(strategy = GenerationType.IDENTITY)
+ private Long id;
+
+ private String customerName;
+
+ private String productName;
+
+ private double amount;
+
+ @Enumerated(EnumType.STRING)
+ private OrderStatus status;
+
+ private LocalDateTime createdAt;
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderRepository.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderRepository.java
new file mode 100644
index 000000000000..4a527743c9bf
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderRepository.java
@@ -0,0 +1,33 @@
+/*
+ * 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.transactionaloutbox;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+/** Spring Data JPA Repository interface for Order entity. */
+@Repository
+public interface OrderRepository extends JpaRepository {}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderService.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderService.java
new file mode 100644
index 000000000000..496302eab19c
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderService.java
@@ -0,0 +1,89 @@
+/*
+ * 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.transactionaloutbox;
+
+import java.time.LocalDateTime;
+import java.time.ZoneOffset;
+import lombok.RequiredArgsConstructor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+/** Service responsible for managing orders and writing outbox events atomically. */
+@Service
+@RequiredArgsConstructor
+public class OrderService {
+
+ private static final Logger LOGGER = LoggerFactory.getLogger(OrderService.class);
+
+ private final OrderRepository orderRepository;
+ private final OutboxRepository outboxRepository;
+
+ /**
+ * Creates a new order and inserts an OutboxEvent into the database atomically within a single
+ * transaction boundary.
+ *
+ * @param customerName name of the customer
+ * @param productName name of the product
+ * @param amount purchase amount
+ * @return persisted Order entity
+ */
+ @Transactional
+ public Order createOrder(String customerName, String productName, double amount) {
+ var now = LocalDateTime.now(ZoneOffset.UTC);
+
+ var order =
+ Order.builder()
+ .customerName(customerName)
+ .productName(productName)
+ .amount(amount)
+ .status(OrderStatus.CREATED)
+ .createdAt(now)
+ .build();
+
+ var savedOrder = orderRepository.save(order);
+ LOGGER.info("Saved order with ID [{}] in database", savedOrder.getId());
+
+ var outboxEvent =
+ OutboxEvent.builder()
+ .aggregateType("Order")
+ .aggregateId(String.valueOf(savedOrder.getId()))
+ .eventType("ORDER_CREATED")
+ .payload(
+ String.format(
+ "{\"orderId\":%d,\"customerName\":\"%s\",\"productName\":\"%s\",\"amount\":%.2f}",
+ savedOrder.getId(), customerName, productName, amount))
+ .status(EventStatus.PENDING)
+ .createdAt(now)
+ .build();
+
+ outboxRepository.save(outboxEvent);
+ LOGGER.info("Saved OutboxEvent for Order ID [{}] in database", savedOrder.getId());
+
+ return savedOrder;
+ }
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderStatus.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderStatus.java
new file mode 100644
index 000000000000..7f0b20d46b16
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OrderStatus.java
@@ -0,0 +1,34 @@
+/*
+ * 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.transactionaloutbox;
+
+/** Enum representing the status of an order. */
+public enum OrderStatus {
+ CREATED,
+ PROCESSING,
+ COMPLETED,
+ CANCELLED
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxEvent.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxEvent.java
new file mode 100644
index 000000000000..7e578ce385d9
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxEvent.java
@@ -0,0 +1,71 @@
+/*
+ * 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.transactionaloutbox;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.EnumType;
+import jakarta.persistence.Enumerated;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Table;
+import java.time.LocalDateTime;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+/**
+ * Represents an event entry stored in the outbox table within the same transaction as business
+ * data.
+ */
+@Entity
+@Table(name = "outbox_events")
+@Data
+@Builder
+@NoArgsConstructor
+@AllArgsConstructor
+public class OutboxEvent {
+
+ @Id
+ @GeneratedValue(strategy = GenerationType.IDENTITY)
+ private Long id;
+
+ private String aggregateType;
+
+ private String aggregateId;
+
+ private String eventType;
+
+ private String payload;
+
+ @Enumerated(EnumType.STRING)
+ private EventStatus status;
+
+ private LocalDateTime createdAt;
+
+ private LocalDateTime processedAt;
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxPublisher.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxPublisher.java
new file mode 100644
index 000000000000..90196e2de0bf
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxPublisher.java
@@ -0,0 +1,88 @@
+/*
+ * 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.transactionaloutbox;
+
+import java.time.LocalDateTime;
+import java.time.ZoneOffset;
+import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+
+/** Background publisher polling PENDING outbox events and dispatching to message broker. */
+@Component
+public class OutboxPublisher {
+
+ private static final Logger LOGGER = LoggerFactory.getLogger(OutboxPublisher.class);
+
+ private final OutboxRepository outboxRepository;
+ private final MessageBroker messageBroker;
+
+ public OutboxPublisher(OutboxRepository outboxRepository, MessageBroker messageBroker) {
+ this.outboxRepository = outboxRepository;
+ this.messageBroker = messageBroker;
+ }
+
+ /**
+ * Periodically polls pending outbox events from database and dispatches them to the message
+ * broker.
+ */
+ @Scheduled(fixedDelay = 5000)
+ public void publishOutboxEvents() {
+ processOutboxEvents();
+ }
+
+ /**
+ * Process pending outbox events from the database and dispatch them to the message broker.
+ *
+ * @return list of processed outbox events
+ */
+ public List processOutboxEvents() {
+ List pendingEvents = outboxRepository.findByStatus(EventStatus.PENDING);
+ if (pendingEvents.isEmpty()) {
+ return pendingEvents;
+ }
+
+ LOGGER.info("Found [{}] PENDING outbox events to publish", pendingEvents.size());
+
+ for (OutboxEvent event : pendingEvents) {
+ try {
+ messageBroker.publish("order-events", event.getPayload());
+ event.setStatus(EventStatus.PROCESSED);
+ event.setProcessedAt(LocalDateTime.now(ZoneOffset.UTC));
+ outboxRepository.save(event);
+ LOGGER.info("Successfully published outbox event ID [{}]", event.getId());
+ } catch (Exception e) {
+ LOGGER.error("Failed to publish outbox event ID [{}]", event.getId(), e);
+ event.setStatus(EventStatus.FAILED);
+ outboxRepository.save(event);
+ }
+ }
+
+ return pendingEvents;
+ }
+}
diff --git a/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxRepository.java b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxRepository.java
new file mode 100644
index 000000000000..dcf409d5f167
--- /dev/null
+++ b/transactional-outbox/src/main/java/com/iluwatar/transactionaloutbox/OutboxRepository.java
@@ -0,0 +1,43 @@
+/*
+ * 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.transactionaloutbox;
+
+import java.util.List;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+/** Spring Data JPA Repository interface for OutboxEvent entity. */
+@Repository
+public interface OutboxRepository extends JpaRepository {
+
+ /**
+ * Finds all outbox events matching the given status.
+ *
+ * @param status event processing status
+ * @return list of matching OutboxEvent records
+ */
+ List findByStatus(EventStatus status);
+}
diff --git a/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/AppTest.java b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/AppTest.java
new file mode 100644
index 000000000000..35cceb7fa173
--- /dev/null
+++ b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/AppTest.java
@@ -0,0 +1,40 @@
+/*
+ * 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.transactionaloutbox;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class AppTest {
+
+ @Test
+ void testAppMainExecutesWithoutErrors() {
+ assertDoesNotThrow(() -> App.main(new String[] {}));
+ }
+}
diff --git a/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OrderServiceTest.java b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OrderServiceTest.java
new file mode 100644
index 000000000000..f7b530ba50bb
--- /dev/null
+++ b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OrderServiceTest.java
@@ -0,0 +1,72 @@
+/*
+ * 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.transactionaloutbox;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import java.util.List;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class OrderServiceTest {
+
+ @Autowired private OrderService orderService;
+
+ @Autowired private OrderRepository orderRepository;
+
+ @Autowired private OutboxRepository outboxRepository;
+
+ @BeforeEach
+ void setUp() {
+ outboxRepository.deleteAll();
+ orderRepository.deleteAll();
+ }
+
+ @Test
+ void testCreateOrderSavesOrderAndOutboxEventAtomically() {
+ Order order = orderService.createOrder("John Doe", "Smartphone", 799.99);
+
+ assertNotNull(order.getId());
+ assertEquals("John Doe", order.getCustomerName());
+ assertEquals(OrderStatus.CREATED, order.getStatus());
+
+ List orders = orderRepository.findAll();
+ assertEquals(1, orders.size());
+
+ List outboxEvents = outboxRepository.findByStatus(EventStatus.PENDING);
+ assertEquals(1, outboxEvents.size());
+
+ OutboxEvent event = outboxEvents.get(0);
+ assertEquals("Order", event.getAggregateType());
+ assertEquals(String.valueOf(order.getId()), event.getAggregateId());
+ assertEquals("ORDER_CREATED", event.getEventType());
+ assertEquals(EventStatus.PENDING, event.getStatus());
+ }
+}
diff --git a/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherTest.java b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherTest.java
new file mode 100644
index 000000000000..234dd6032195
--- /dev/null
+++ b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherTest.java
@@ -0,0 +1,80 @@
+/*
+ * 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.transactionaloutbox;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import java.util.List;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class OutboxPublisherTest {
+
+ @Autowired private OrderService orderService;
+
+ @Autowired private OutboxPublisher outboxPublisher;
+
+ @Autowired private OutboxRepository outboxRepository;
+
+ @Autowired private MessageConsumer messageConsumer;
+
+ @BeforeEach
+ void setUp() {
+ outboxRepository.deleteAll();
+ messageConsumer.clearMessages();
+ }
+
+ @Test
+ void testProcessOutboxEventsWhenNoPendingEvents() {
+ List processed = outboxPublisher.processOutboxEvents();
+ assertTrue(processed.isEmpty());
+ }
+
+ @Test
+ void testProcessOutboxEventsPublishesAndUpdatesStatusToProcessed() {
+ orderService.createOrder("Jane Smith", "Tablet", 499.00);
+
+ List pendingBefore = outboxRepository.findByStatus(EventStatus.PENDING);
+ assertEquals(1, pendingBefore.size());
+
+ List processedEvents = outboxPublisher.processOutboxEvents();
+ assertEquals(1, processedEvents.size());
+
+ List pendingAfter = outboxRepository.findByStatus(EventStatus.PENDING);
+ assertEquals(0, pendingAfter.size());
+
+ List processedAfter = outboxRepository.findByStatus(EventStatus.PROCESSED);
+ assertEquals(1, processedAfter.size());
+ assertNotNull(processedAfter.get(0).getProcessedAt());
+
+ assertEquals(1, messageConsumer.getConsumedMessages().size());
+ }
+}
diff --git a/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherUnitTest.java b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherUnitTest.java
new file mode 100644
index 000000000000..4f4cb891459a
--- /dev/null
+++ b/transactional-outbox/src/test/java/com/iluwatar/transactionaloutbox/OutboxPublisherUnitTest.java
@@ -0,0 +1,66 @@
+/*
+ * 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.transactionaloutbox;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import java.util.List;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.InjectMocks;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+@ExtendWith(MockitoExtension.class)
+class OutboxPublisherUnitTest {
+
+ @Mock private OutboxRepository outboxRepository;
+
+ @Mock private MessageBroker messageBroker;
+
+ @InjectMocks private OutboxPublisher outboxPublisher;
+
+ @Test
+ void testProcessOutboxEventsHandlesBrokerException() {
+ OutboxEvent event =
+ OutboxEvent.builder().id(1L).payload("test payload").status(EventStatus.PENDING).build();
+
+ when(outboxRepository.findByStatus(EventStatus.PENDING)).thenReturn(List.of(event));
+ doThrow(new RuntimeException("Broker failure"))
+ .when(messageBroker)
+ .publish(anyString(), anyString());
+
+ List result = outboxPublisher.processOutboxEvents();
+
+ assertEquals(1, result.size());
+ assertEquals(EventStatus.FAILED, event.getStatus());
+ verify(outboxRepository).save(event);
+ }
+}
From 6055caf34a799f72316bbb73281d0a1e4bbff1a6 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Sun, 30 Aug 2026 14:47:21 +0300
Subject: [PATCH 2/3] build(deps): bump
com.fasterxml.jackson.core:jackson-databind (#3573)
Bumps [com.fasterxml.jackson.core:jackson-databind](https://github.com/FasterXML/jackson) from 2.16.1 to 2.18.9.
- [Commits](https://github.com/FasterXML/jackson/commits)
---
updated-dependencies:
- dependency-name: com.fasterxml.jackson.core:jackson-databind
dependency-version: 2.18.9
dependency-type: direct:production
...
Signed-off-by: dependabot[bot]
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
---
microservices-messaging/pom.xml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/microservices-messaging/pom.xml b/microservices-messaging/pom.xml
index 8fb9d59c4f74..0fe26df232d8 100644
--- a/microservices-messaging/pom.xml
+++ b/microservices-messaging/pom.xml
@@ -74,7 +74,7 @@
com.fasterxml.jackson.core
jackson-databind
- 2.16.1
+ 2.18.9
From 41625d8d354cdf6b6f10a82e29c2392b3efd5d20 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Sun, 30 Aug 2026 14:52:26 +0300
Subject: [PATCH 3/3] build(deps): bump org.apache.kafka:kafka-clients (#3574)
Bumps org.apache.kafka:kafka-clients from 3.6.1 to 3.9.2.
---
updated-dependencies:
- dependency-name: org.apache.kafka:kafka-clients
dependency-version: 3.9.2
dependency-type: direct:production
...
Signed-off-by: dependabot[bot]
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
---
microservices-messaging/pom.xml | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/microservices-messaging/pom.xml b/microservices-messaging/pom.xml
index 0fe26df232d8..0ed9491da800 100644
--- a/microservices-messaging/pom.xml
+++ b/microservices-messaging/pom.xml
@@ -41,7 +41,7 @@
1.26.0-SNAPSHOT
- 3.6.1
+ 3.9.2