Kafka Streams sample demo for TopologyTestDriver

Fixes: #1853

* Demonstrating Kafka Streams `TopologyTestDriver`
* README updates in the sample
* Update Spring Boot parent version of the samples to 3.2.5

samples/README.adoc

@@ -1,7 +1,8 @@
 == Samples
 
-* sample-01 - simple producer/consumer with dead-letter topic
-* sample-02 - multi-method listener
-* sample-03 - transactions
-* sample-04 - topic based (non-blocking) retry
-* sample-05 - global embedded Kafka testing
+* sample-01 - Simple producer/consumer with dead-letter topic
+* sample-02 - Multi-method listener
+* sample-03 - Transactions
+* sample-04 - Topic based (non-blocking) retry
+* sample-05 - Global embedded Kafka testing
+* sample-06 - Kafka Streams tests with TopologyTestDriver

samples/sample-01/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>3.2.1</version>
+		<version>3.2.5</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 

samples/sample-02/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>3.2.1</version>
+		<version>3.2.5</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 

samples/sample-03/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>3.2.1</version>
+		<version>3.2.5</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 

samples/sample-04/pom.xml

@@ -14,7 +14,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>3.2.1</version>
+		<version>3.2.5</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 

samples/sample-05/pom.xml

@@ -5,7 +5,7 @@
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
-		<version>3.2.1</version>
+		<version>3.2.5</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>
 

samples/sample-06/README.adoc

@@ -0,0 +1,36 @@
+== Sample 6
+
+This sample demonstrates a simple Kafka Streams topology tested with TopologyTestDriver.
+
+The application contains a simple Kafka Streams topology that counts the keys seen so far in a stateful manner.
+The corresponding `TopologyTestDriver` based JUnit test verifies the behavior of the business logic in the Kafka Streams topology.
+
+
+Console output describe the topology as shown below:
+
+  .   ____          _            __ _ _
+ /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
+( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
+ \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
+  '  |____| .__|_| |_|_| |_\__, | / / / /
+ =========|_|==============|___/=/_/_/_/
+ :: Spring Boot ::                (v2.5.2)
+
+2021-06-30 17:38:33.637  INFO 92063 --- [           main] com.example.ApplicationTests             : Starting ApplicationTests using Java 11.0.10 on C02FL1KSMD6T with PID 92063 (started by igomez in /Users/igomez/Projects/spring-kafka/samples/sample-05)
+2021-06-30 17:38:33.638  INFO 92063 --- [           main] com.example.ApplicationTests             : The following profiles are active: test
+2021-06-30 17:38:35.027  INFO 92063 --- [           main] com.example.ApplicationTests             : Started ApplicationTests in 1.73 seconds (JVM running for 2.833)
+2021-06-30 17:38:35.695  INFO 92063 --- [           main] com.example.ApplicationTests             : Topologies:
+   Sub-topology: 0
+    Source: KSTREAM-SOURCE-0000000000 (topics: [input])
+      --> KSTREAM-AGGREGATE-0000000002
+    Processor: KSTREAM-AGGREGATE-0000000002 (stores: [KSTREAM-AGGREGATE-STATE-STORE-0000000001])
+      --> KTABLE-SUPPRESS-0000000003
+      <-- KSTREAM-SOURCE-0000000000
+    Processor: KTABLE-SUPPRESS-0000000003 (stores: [KTABLE-SUPPRESS-STATE-STORE-0000000004])
+      --> KTABLE-TOSTREAM-0000000005
+      <-- KSTREAM-AGGREGATE-0000000002
+    Processor: KTABLE-TOSTREAM-0000000005 (stores: [])
+      --> KSTREAM-SINK-0000000006
+      <-- KTABLE-SUPPRESS-0000000003
+    Sink: KSTREAM-SINK-0000000006 (topic: output)
+      <-- KTABLE-TOSTREAM-0000000005

samples/sample-06/pom.xml

@@ -0,0 +1,128 @@
+<?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>
+
+	<groupId>com.example</groupId>
+	<artifactId>kafka-sample-06</artifactId>
+	<version>3.2.0-SNAPSHOT</version>
+	<packaging>jar</packaging>
+
+	<name>kafka-sample-06</name>
+	<description>Kafka Sample 6</description>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>3.2.5</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
+		<java.version>17</java.version>
+	</properties>
+
+	<dependencies>
+
+		<dependency>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.apache.kafka</groupId>
+			<artifactId>kafka-streams</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.apache.kafka</groupId>
+			<artifactId>kafka-streams-test-utils</artifactId>
+			<scope>test</scope>
+		</dependency>
+
+		<dependency>
+			<groupId>org.apache.kafka</groupId>
+			<artifactId>kafka-clients</artifactId>
+			<scope>test</scope>
+			<classifier>test</classifier>
+		</dependency>
+
+		<dependency>
+			<groupId>org.awaitility</groupId>
+			<artifactId>awaitility</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+	<repositories>
+		<repository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/libs-snapshot-local</url>
+		</repository>
+		<repository>
+			<id>spring-milestones</id>
+			<name>Spring milestones</name>
+			<url>https://repo.spring.io/libs-milestone-local</url>
+		</repository>
+		<repository>
+			<id>rsocket-snapshots</id>
+			<name>RSocket Snapshots</name>
+			<url>https://oss.jfrog.org/oss-snapshot-local</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</repository>
+		<repository>
+			<id>spring-releases</id>
+			<name>Spring Releases</name>
+			<url>https://repo.spring.io/release</url>
+		</repository>
+	</repositories>
+	<pluginRepositories>
+		<pluginRepository>
+			<id>spring-snapshots</id>
+			<name>Spring Snapshots</name>
+			<url>https://repo.spring.io/snapshot</url>
+			<snapshots>
+				<enabled>true</enabled>
+			</snapshots>
+		</pluginRepository>
+		<pluginRepository>
+			<id>spring-milestones</id>
+			<name>Spring Milestones</name>
+			<url>https://repo.spring.io/milestone</url>
+			<snapshots>
+				<enabled>false</enabled>
+			</snapshots>
+		</pluginRepository>
+		<pluginRepository>
+			<id>spring-releases</id>
+			<name>Spring Releases</name>
+			<url>https://repo.spring.io/release</url>
+		</pluginRepository>
+	</pluginRepositories>
+
+
+</project>

samples/sample-06/src/main/java/com/example/Application.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.kafka.annotation.EnableKafkaStreams;
+
+/**
+ *
+ * @author Nacho Munoz
+ * @since 3.2.0
+ */
+@EnableKafkaStreams
+@SpringBootApplication
+public class Application {
+
+	private final Logger logger = LoggerFactory.getLogger(Application.class);
+
+	public static void main(String[] args) {
+		SpringApplication.run(Application.class, args);
+	}
+
+}

samples/sample-06/src/main/java/com/example/Topology.java

@@ -0,0 +1,64 @@
+/*
+ * Copyright 2024 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.example;
+
+import java.time.Duration;
+
+import org.apache.kafka.common.serialization.Serdes;
+import org.apache.kafka.streams.StreamsBuilder;
+import org.apache.kafka.streams.kstream.Consumed;
+import org.apache.kafka.streams.kstream.Suppressed;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.stereotype.Component;
+
+
+/**
+ * A basic topology that counts records by key and materialises the output into a new topic
+ *
+ * @author Nacho Munoz
+ * @author Soby Chacko
+ * @since 3.2.0
+ */
+@Configuration
+@Component
+public class Topology {
+	private final String inputTopic;
+
+	private final String outputTopic;
+
+	@Autowired
+	public Topology(@Value("${input-topic.name}") final String inputTopic,
+					@Value("${output-topic.name}") final String outputTopic) {
+		this.inputTopic = inputTopic;
+		this.outputTopic = outputTopic;
+	}
+
+	@Autowired
+	public void defaultTopology(final StreamsBuilder builder) {
+		builder.stream(inputTopic, Consumed.with(Serdes.Integer(), Serdes.String()))
+				.groupByKey()
+				.count()
+				.suppress(Suppressed.untilTimeLimit(Duration.ofMillis(5), Suppressed.BufferConfig.unbounded()))
+				.toStream()
+				.to(outputTopic);
+
+	}
+
+}

samples/sample-06/src/main/resources/application-test.properties

@@ -0,0 +1,6 @@
+logging.level.root=off
+logging.level.com.example=info
+
+bootstrap.servers=
+spring.kafka.properties.bootstrap.servers=${bootstrap.servers}
+spring.kafka.streams.application-id=Sample-06-Service-Test

samples/sample-06/src/main/resources/application.properties

@@ -0,0 +1,4 @@
+logging.level.root=off
+logging.level.com.example=info
+
+spring.kafka.streams.application-id=Sample-06-Service

samples/sample-06/src/main/resources/application.yml

@@ -0,0 +1,6 @@
+logging:
+  level.root: info
+input-topic:
+  name: input
+output-topic:
+  name: output