RecordRecoverableProcessor and DltAwareProcessor example (#254)

* example implementation with tests

update tests and README
Add implementation of junit

* Added fixes for comments

Made the test much more deterministic

* Fixed compilation error from IDE vs CLI invocation

* Removed unnecessary annotation

Handled by spring boot, not needed for Kafka autoconfiguration.

Author: StevenPG

kafka-batch-sample/src/main/java/com/example/demo/KafkaBatchSampleApplication.java

@@ -100,7 +100,7 @@ class BatchProduce extends Base {
 	@Bean
 	Function<List<String>, List<Message<String>>> consumer() {
 		return list -> list.stream()
-			.map(string -> string.toUpperCase())
+			.map(String::toUpperCase)
 			.map(uppercasedString -> MessageBuilder.withPayload(uppercasedString).build())
 			.collect(Collectors.toList());
 	}

kafka-streams-samples/kafka-streams-recoverable/.gitignore

@@ -0,0 +1,24 @@
+target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+nbproject/private/
+build/
+nbbuild/
+dist/
+nbdist/
+.nb-gradle/

kafka-streams-samples/kafka-streams-recoverable/README.adoc

@@ -0,0 +1,26 @@
+== What is this app?
+
+This is an example of a Spring Cloud Stream processor using Kafka Streams support.
+
+This is a demonstration of utilizing the RecordRecoverableProcessor and DltAwareProcessor.
+
+The example increments a java.util.Suppler integer by 1 every 2 seconds, and publishes
+to the `topic-in` kafka topic.
+
+There's then two processors, both of which are listening on `topic-in`.
+
+The first processor throws an exception in the workflow when the integer is divisible by 5.
+The second processor throws an exception in the workflow when the integer is divisible by 4.
+
+This sample uses lambda expressions and thus requires Java 8+.
+
+=== Running the app:
+
+`docker-compose up -d`
+
+Go to the root of the repository and do: `./mvnw clean package`
+
+`java -jar target/kafka-streams-recoverable-0.0.1-SNAPSHOT.jar`
+
+The Supplier will automatically publish messages and the consumers
+will write messages to the application log.

kafka-streams-samples/kafka-streams-recoverable/docker-compose.yml

@@ -0,0 +1,19 @@
+version: '3'
+services:
+    kafka:
+      image: wurstmeister/kafka
+      container_name: kafka-dlq
+      ports:
+        - "9092:9092"
+      environment:
+        - KAFKA_ADVERTISED_HOST_NAME=127.0.0.1
+        - KAFKA_ADVERTISED_PORT=9092
+        - KAFKA_ZOOKEEPER_CONNECT=zookeeper:2181
+      depends_on:
+        - zookeeper
+    zookeeper:
+      image: wurstmeister/zookeeper
+      ports:
+        - "2181:2181"
+      environment:
+        - KAFKA_ADVERTISED_HOST_NAME=zookeeper