We'll send a Java Object as. Sending Key Value Messages with the Kafka Console Producer When working with Kafka you might find yourself using the kafka-console-producer (kafka-console-producer. He has been a committer on Spring Integration since 2010 and has led that project for several years, in addition to leading Spring for Apache Kafka and Spring AMQP (Spring for RabbitMQ). Storage: Data written to Kafka is written to disk and replicated for fault-tolerance. Kafka Consumer configuration. Each message within a partition has an identifier called its offset. x, consumers use Apache ZooKeeper for consumer group coordination, and a number of known bugs can result in long-running rebalances or even failures of the rebalance algorithm. Back in January 2019, I presented an introduction to Kafka basics and spring-kafka at a South Bay JVM User Group meetup. No problem. Consequently, with the right developer talent creating the consumer code, Kafka can support a large number of consumers and retain large amounts of data with very little overhead. Since all 3 of your consumers are in the same group they will divide the partitions amongst themselves from a topic. Spring Cloud Stream is built on top of existing Spring frameworks like Spring Messaging and Spring Integration. And Spring Boot 1. Let’s start with the Gradle build file. The Spring Boot app starts and the consumers are registered in Kafka, which assigns a partition to them. Kafka Tutorial Installing Kafka. To import in to Eclipse. We will implement a simple example to send a message to Apache Kafka using Spring Boot Spring Boot + Apache Kafka Hello World Example. I was not able to send messages to the consumer by simply calling. Advantages of Multiple Clusters. Consumers label themselves with a consumer group name, and each record published to a topic is delivered to one consumer instance within each subscribing consumer group. Kafka Producer API helps to pack the message and deliver it to Kafka Server. ZooKeeper serves as the coordination interface between the kafka broker and its consumers. Kafka does not know which consumer consumed which message from the topic. But unlike Kafka's auto rebalancing between consumers and partitions, Event Hub provides a kind of preemptive mode. Initially Siphon was engineered to run on Microsoft’s internal data center fabric. Kafka assigns the partitions of a topic to the consumer in a group, so that each partition is consumed by exactly one consumer in the group. Thanks to the combination of: Kubernetes Minikube The Yolean/kubernetes-kafka GitHub Repo with Kubernetes yaml files that creates allRead More. This tutorial demonstrates how to process records from a Kafka topic with a Kafka Consumer. A consumer group consists of multiple consumers amongst which messages are distributed. com Spring Kafka Consumer Producer Example 10 minute read In this post, you’re going to learn how to create a Spring Kafka Hello World example that uses Spring Boot and Maven. Update in order to post messages to the Kafka topic. configuration. In the next article we will learn how to implement a Kafka Producer and Consumer using Spring for Kafka. In a recent article I described how to implement a simple Node. 2 Console Producers and Consumers Follow the steps given below…. We can also see which Consumers are consuming which topics, from within Kafka Manager. Update in order to post messages to the Kafka topic. So, each consumer group can manage its offset independently, by partition. 2015-10-09. An interesting use case that has emerged is the microservices architecture. A broker is a kafka server which stores/keeps/maintains incoming messages in files with offsets. We just create a configuration class which consist of a spring @Bean that generates our KafkaListenerContainerFactory. Failed To Construct Kafka Consumer Spring Boot. To say the. 9, the new high level KafkaConsumer client is availalbe. Browse to your source code location. auto-offset-reset=earliest We need the first property because we are using group management to assign topic partitions to consumers, so we need a group. JS program that reads and processes records from a delimiter separated file. From the ground up it has been designed to provide high throughput, fast performance, scalability and high availability. Today, many people use Kafka to fill this latter role. With over 30 pre-defined alerts and over 15 pre-built monitoring dashboards, users can deploy quickly without the time, skill and expense necessary. x manually using YAML files or through the OpenShift Container Platform Operator Hub. Surprisingly, keeping track of consumer position is one of the key performance points of a messaging system , so Kafka's design leaves it up to the consumers to pull. auto-offset-reset=earliest We need the first property because we are using group management to assign topic partitions to consumers, so we need a group. Check the screen from running application. One thing Kafka is famous for is that multiple producers in Kafka can write to the same topic, and multiple consumers can read from the same topic with no issue. id) the data will be balanced over all the consumers within the group. To send messages to our topic, we are using inbuilt producer script from Kafka. Read more on KAFKAs website. Where a producer will produce items in a common place like a Queue. Don't Use Apache Kafka Consumer Groups the Wrong Way! Apache Kafka is great — but if you're going to use it, you have to be very careful not to break things. At the same time, scaling is more difficult in this case. Surprisingly, keeping track of consumer position is one of the key performance points of a messaging system , so Kafka's design leaves it up to the consumers to pull. Do you have any thoughts on how to system (integration) test a system that is kafka-based, particularly where for the time being one has to validate data coming off kafka via a consumer and feed test data in via a producer, but in live system under test, the flow is more asynchronous, with multiple brokers, zookeepers, producers, consumers, and. configuration. The processing rates in Kafka can exceed beyond 100k/seconds. Consumer has to mention the offset for the topic and Kafka starts serving the messages in order from the given offset. Starting from version 2. We have created receiver for each partition to receive messages. It uses JSON for defining data types/protocols and serializes data in a compact binary format. Description: Learn the fundamentals and advanced concepts of Apache Kafka in this course. Create Multi-threaded Apache Kafka Consumer - Source Code The source code includes the implementation for both above models. On the consumer side a powerful feature of Kafka is that it allows multiple consumers to read the same messages. Spring Cloud Stream makes it work the same, transparently. It doesn't recognize what's inside a message or what type it is. I started up an instance of my consumer (java -jar event-hubs-kafka-consumer-0. Topics can be partitioned. For example some properties needed by the application such as spring. To customize it, you need to build configuration file. You have to deal with multiple topics, you need multiple partitions. auto-offset-reset=earliest The first because we are using group management to assign topic partitions to consumers so we need a group, the second to ensure the new consumer group will get the messages we just sent, because the container might start after the sends have completed. Basically I need to run these consumers on multiple servers so group. We start by creating a Spring Kafka Producer which is able to send messages to a Kafka topic. howtoprogram. (Spring Cloud Stream consumer groups are similar to and inspired by Kafka consumer groups. As of today, you have to also add the Spring Milestone Repository in order to do so. It is the consumers responsibility to keep track of data it has consumed. The following diagram depicts a single topic with. xml logs to Apache Kafka. Questions: In my Spring Boot/Kafka application before the library update, I used the following class org. These processes can either be running on the same machine or, as is more likely, they can be distributed over many machines to provide scalability and fault tolerance for processing. Thus we can achieve more throughput. Queue: Competing Consumers Pattern Jef King. Java consumer A lot of properties need to be configured for the Kafka consumer. RELEASE Kafka-2. A Kafka queue supports a variable number of consumers (i. 9-消费端 Consumer Priorities consumer-producer Forbid consumer Kafka kafka kafka kafka kafka kafka kafka Kafka Kafka Kafka Spring Kafka. In this post we are going to look at how to use Spring for Kafka which provides high level abstraction over Kafka Java Client API to make it easier to work with Kafka. it is supposed to be consumed by both the groups, but it is consumed by only one listener. A typical use case might be deleting a topic or adding partitions to a topic. Kafka Streams has a low barrier to entry: You can quickly write and run a small-scale proof-of-concept on a single machine; and you only need to run additional instances of your application on multiple machines to scale up to high-volume production workloads. autoRebalanceEnabled When true , topic partitions will be automatically rebalanced between the members of a consumer group. Consumer instances can be in separate processes or on separate machines. Kafka is like topics in JMS, RabbitMQ, and other MOM systems for multiple consumer groups. Multiple Kafka consumer groups can be run in parallel: Of course you can run multiple, independent logical consumer applications against the same Kafka topic. Update in order to post messages to the Kafka topic. Integrate Apache Camel with Apache Kafka - 1 Recently I started looking into Apache Kafka as our distributed messaging solution. By default the buffer size is 100 messages and can be changed through the highWaterMark option. Kafka does not deletes consumed messages with its default settings. To send messages to our topic, we are using inbuilt producer script from Kafka. Consequently, with the right developer talent creating the consumer code, Kafka can support a large number of consumers and retain large amounts of data with very little overhead. The consumer will retrieve messages for a given topic and print them to the console. Kafka is different from most other message queues in the way it maintains the concept of a “head” of the queue. Multiple Nodes Multiple Brokers. 2 Console Producers and Consumers Follow the steps given below…. Spring Kafka supports us in integrating Kafka with our Spring application easily and a simple example as well. Process PDF files in Pentaho kettle. Now we have requirement where we need more than one receivers to consumer message from. The ecosystem also provides a REST proxy which allows easy integration via HTTP and JSON. Running redis-server without any options is good for test, but not enough for production environment. Config First Bootstrap 10. But we are expecting the release any week now, so that might not be the case any longer while you read this article. LinkedIn Newsfeed is powered by Kafka LinkedIn recommendations are powered by Kafka. Kafka is a distributed publish-subscribe messaging system that is designed to be fast, scalable, and durable. The following example shows how to setup a batch listener using Spring Kafka, Spring Boot, and Maven. These libraries promote. InstanceAlreadyExistsException: kafka. Below is my setup. Consumers can be grouped in so called consumer-groups, which makes it possible for multiple consumers to act as one when it comes to single-delivery. Learning Apache Kafka Second Edition provides you with step-by-step. Spring Cloud Stream has the concepts of producers and consumers; when using the messaging paradigm, MessageChannels are bound to destinations (e. Intro Producers / Consumers help to send / receive message to / from Kafka SASL is used to provide authentication and SSL for encryption JAAS config files are used to read kerberos ticket and authenticate as a part of SASL Kafka Version used in this article :0. In the following tutorial we demonstrate how to setup a batch listener using Spring Kafka, Spring Boot and Maven. Kafka not only provides a system for log management, but it can also handle heterogeneous aggregation of several logs. Schema Registry Serializer and Formatter¶. However, leaders are special, in that producers and consumers can only interact with leaders in a Kafka cluster. The processing rates in Kafka can exceed beyond 100k/seconds. LinkedIn notifications are powered by Kafka. A typical use case might be deleting a topic or adding partitions to a topic. I would like to have the Multiple consumers for a partition, I heard that with Consumer group it is possible. Running the Kafka Consumer. Conclusion. Kafka has stronger ordering guarantees than a traditional messaging system, too. Scenario #1: Topic T subscribed by only one CONSUMER GROUP CG- A having 4 consumers. kafka compression using high level consumer and simple consumer Tag: java , c++ , hadoop , apache-kafka , snappy In my application, we are using Kafka high level consumer which consumes the decompressed data without any issues if the producer and consumer compress and decompress the data using java API. We are using spring kafka to consume messages. group=app1) and passed in that property. It also contains support for Message-driven POJOs with @KafkaListener annotations and a listener container. By consuming the special, internal Kafka topic __consumer_offsets, Burrow can act as a centralized service, separate from any single consumer, giving you an objective view of consumers based on both their committed offsets (across topics) and broker state. Spring Kafka supports us in integrating Kafka with our Spring application easily and a simple example as well. jar –spring. We can override these defaults using the application. There’s a lot more to Kafka than I can get into in this post and the original documentation is much clearer, so check out the documentation at https://kafka. The producer and consumer components in this case are your own implementations of kafka-console-producer. For convenience I copied essential terminology definitions directly from Kafka documentation:. The company’s release of Confluent Platform 5. Surprisingly, we replaced it with Kafka Consumers last week. Mongo Express. While there are potentially many ways to use an interceptor interface (for example. I am going to review our experience and try to write the advantages and disadvantages of both technologies in this short article. My first route consumes from Kafka Consumer Endpoint. Kafka Tutorial: Writing a Kafka Producer in Java. It needs resources to make the content available and host the website. To import in to Eclipse. Basically I need to run these consumers on multiple servers so group. Since each topic has 1 partition only one consumer can get it assigned. The package com. 11 release, thereby eliminating the need for application developers to code the important feature themselves. Should Apache Kafka and Hadoop be installed seperatedly (on a diffrent cluster)? hadoop,apache-kafka,kafka. Kafka can support a large number of consumers and retain large amounts of data with very little overhead. Kafka makes the streaming data durable by persisting incoming messages on disk using a log data structure. And there are multiple consumers which are processing these records one by one parallel. Kafka Brokers form a cluster. The consumer will transparently handle the failure of servers in the Kafka cluster, and adapt as topic-partitions are created or migrate between brokers. id - Paizo Aug 2 '18 at 12:28. Apache Kafka - Getting Started - Scenarios - Multi PartitionTopic - Multiple Consumers Kafka Consumer and Event Sourcing from Scratch with Apache Kafka and Spring - Kenny. If this option is enabled then an instance of KafkaManualCommit is stored on the Exchange message header, which allows end users to access this API and perform manual offset commits via the Kafka consumer. Below is my setup. We start by configuring the BatchListener. We are pleased to announce the following releases are now available. 여러 소비자와 같은 그룹을 사용하면 부하가 분산되어 토픽에서 읽습니다. id so the messages are distributed among the various consumers in the same group for the same topic. Spring Boot uses sensible default to configure Spring Kafka. Basically I need to run these consumers on multiple servers so group. 1? Ways to manually commit offset in kafka consumers utilizing spring kafka; Why do I lose the console output? Why my Kafka consumers with same group id are not being balanced?. A modern data platform requires a robust Complex Event Processing (CEP) system, a cornerstone of which is a distributed messaging system. Spring provides good support for Kafka and provides the abstraction layers to work with over the native Kafka Java clients. You can go for Kafka if the data will be consumed by multiple applications. On the contrary, a consumer can be in charge of several partitions. consumer-properties. 5 What is the role of the ZooKeeper in Kafka? Ans. You can go for Kafka if the data will be consumed by multiple applications. Apache Kafka i About the Tutorial Apache Kafka was originated at LinkedIn and later became an open sourced Apache project in 2011, then First-class Apache project in 2012. Config First Bootstrap 10. you can have 1 micro service to do the process and run multiple instance of that with different group. Apache Kafka - Example of Producer/Consumer in Java If you are searching for how you can write simple Kafka producer and consumer in Java, I think you reached to the right blog. Because Kafka consumers pull data from the topic, different consumers can consume the messages at different pace. From no experience to actually building stuff. If your system exists includes multiple servers or services that need to integrate with each other then you could probably benefit from Apache Kafka. Like any MapR Streams/Kafka consumer the auto. Learn how to process and aggregate huge streams of IoT data using Strimzi and Apache Kafka on Red Hat OpenShift. ActiveMq is a Java Open Source, it is simple JMS solution for concurrent, consumers and producers architecture in integrated development. And then we need to tell Spring Cloud Stream the host name where Kafka and Zookeeper are running – defaults are localhost, we are running them in one Docker container named kafka. Read more on KAFKAs website. A broker is a kafka server which stores/keeps/maintains incoming messages in files with offsets. Kafka has topics and producers publish to the topics and the subscribers (Consumer Groups) read from the topics. To generate IDEA metadata (. Conclusion. Must be one of random, round_robin, or hash. It also provides support for Message-driven POJOs with @KafkaListener annotations and a "listener container". Recent Posts. 4 (550 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. The consumer will retrieve messages for a given topic and print them to the console. Kafka and Logstash 1. Using Kafka with Junit One of the neat features that the excellent Spring Kafka project provides, apart from a easier to use abstraction over raw Kafka Producer and Consumer , is a way to use Kafka in tests. In the last post, we saw how to integrate Kafka with Spring Boot application. My objective here is to show how Spring Kafka provides an abstraction to raw Kafka Producer and Consumer API's that is easy to use and is familiar to someone with a Spring background. Is there any configuration where we need to change to let kafka know to hold off acknowledgement for that much time? My kafka producer produces messages for every 10 mins. It subscribes to one or more topics in the Kafka cluster. In this post, we explore more details of a spring boot application with Kafka. Scenario #1: Topic T subscribed by only one CONSUMER GROUP CG- A having 4 consumers. For example. We provide a "template" as a high-level abstraction for sending messages. Apache Kafka has a built-in system to resend the data if there is any failure while processing the data, with this inbuilt mechanism it is highly fault-tolerant. consumer-properties. On the consumer side a powerful feature of Kafka is that it allows multiple consumers to read the same messages. However, although the server hands out messages in order, the messages are deliv. ; Ammon, Charles J. Producers and Consumers are notified by the ZooKeeper service about the presence of new brokers or failure of the broker in theKafka system. For example some properties needed by the application such as spring. 4 (550 ratings) Course Ratings are calculated from individual students’ ratings and a variety of other signals, like age of rating and reliability, to ensure that they reflect course quality fairly and accurately. Kafka scales topic consumption by distributing partitions among a consumer group, which is a set of consumers sharing a common group identifier. People who worked with kafka-python or Java Client probably know that the poll() API is designed to ensure liveness of a Consumer Group. To import in to Eclipse. For consuming messages, we need to configure a ConsumerFactory and a KafkaListenerContainerFactory. Spring Boot Kafka Consume JSON Messages: As part of this example, I am going to create a Kafka integrated spring boot application and publish JSON messages from Kafka producer console and read these messages from the application using Spring Boot Kakfka Listener. Kafka has the concept of “partitions” within the topics which could provide both ordering guarantees and load balancing over a pool of consumer processes. As mentioned previously on this post, we want to demonstrate different ways of deserialization with Spring Boot and Spring Kafka and, at the same time, see how multiple consumers can work in a load-balanced manner when they are part of the same consumer-group. Mongo Express. In the previous post Kafka Tutorial - Java Producer and Consumer we have learned how to implement a Producer and Consumer for a Kafka topic using plain Java Client API. RTView's Solution Package for Apache Kafka provides a complete Kafka monitoring solution with pre-built dashboards for monitoring Kafka brokers, producers, consumers, topics, and Kafka Zookeepers. And Spring Boot 1. It exploits a new built-in Kafka protocol that allows to combine multiple consumers in a so-called Consumer Group. Kafka does not offer the ability to delete. My project structure looks like this. Recently, I have some more article on Apache Kafka. Spring Boot Kafka JSON Message: We can publish the JSON messages to Apache Kafka through spring boot application. streams are consumed in chunks and in kafka-node each chunk is a kafka message; a stream contains an internal buffer of messages fetched from kafka. Solace’s hierarchical topic structure (multiple levels, delimited by slash /) and wildcard ability allows for much more fine-grained filtering at the broker than you may be able to get with a Kafka broker. Before this approach, let's do it with annotations. A typical microservices solutions will have dozens of “independent” services interacting with each other, and that is a huge problem if not handled properly. Kafka output broker event partitioning strategy. As of today, you have to also add the Spring Milestone Repository in order to do so. So I have also decided to dive in it and understand it. That is stepping stone on the way to my real goal: publish a load of messages on a Kafka Topic, based on records in a file, and semi-randomly spread over time. Akka Kafka Streams app or Ratpack/RxJava/Spring Reactor. Next we create a Spring Kafka Consumer which is able to listen to messages send to a Kafka topic. The mechanism that we are proposing is inspired by the interceptor interface in Apache Flume. So I have also decided to dive in it and understand it. consumer-properties. The following properties are available for Kafka consumers only and must be prefixed with spring. Now we have requirement where we need more than one receivers to consumer message from. Kafka Manager is an appealing alternative, as opposed to connecting with the Kafka container, with a docker exec command, to interact with Kafka. Spring Cloud Config Client 10. We start by adding headers using either Message> or ProducerRecord. Sample scenario The sample scenario is a simple one, I have a system which produces a message and another which processes it. 2015-10-09. As the diagram above shows, Kafka does require external services to run - in this case Apache Zookeeper, which is often regarded as non-trivial to understand, setup. We explored a few key concepts and dove into an example of configuring spring-Kafka to be a producer/consumer client. If you use the same GROUP_ID_CONFIG for more than one consumer, Kafka will assume that both of them are part of a single group, and it will deliver messages to only one of the consumers. We will be doing spring boot configurations and stream log4j2. For this example, check the spring-kafka-multi-threaded-consumption sub project. Import source code into Eclipse. Consequently, with the right developer talent creating the consumer code, Kafka can support a large number of consumers and retain large amounts of data with very little overhead. Kafka topics, Rabbit Exchanges/Queues). But don't take my word for it. 그룹의 각 소비자는 레코드의 일부를 받습니다. Multiple node – multiple broker cluster This cluster scenario is not discussed in detail in this book, but as in the case of multiple-node Kafka cluster, where we set up multiple brokers on each node, we should install Kafka on each node of the cluster, and all the brokers from the different nodes need to connect to the same ZooKeeper. 5 What is the role of the ZooKeeper in Kafka? Ans. A few months ago, I wrote about creating your own sink connector after we started using ours. The consumer fetches a batch of messages per partition. Click Finish button to finish the importing. Spring Kafka dependencies. consumer:type=consumer-node-metrics,client-id=consumer-1,node-id=node--1 Here is the full stack trace:. The examples in this repository demonstrate how to use the Kafka Consumer, Producer, and Streaming APIs with a Kafka on HDInsight cluster. Apache Kafka is usually used as an integration hub between multiple servers and services. With Spring, develop application to interact with Apache Kafka is becoming easier. Before we start implementing any component, let’s lay out an architecture or a block diagram which we will try to build throughout this series one-by-one. ActiveMq is a Java Open Source, it is simple JMS solution for concurrent, consumers and producers architecture in integrated development. group property to specify a group name. The consumer or consumer group has to keep a track of the consumption. Kafka Source is an Apache Kafka consumer that reads messages from Kafka topics. Introduction to Apache Kafka using Spring. On the contrary, a consumer can be in charge of several partitions. All Programming Tutorials website provides tutorials on topics covering Big Data, Hadoop, Spark, Storm, Android, NodeJs, Java, J2EE, Multi-threading, Google Maps. Kafka maintains this message ordering for you. l be redistributed how other consumers will know the offset of died consumer - shiv455 Feb 22 '16 at 19:48 1) You can use low level consumer API (or there is entirely new consumer API in the new Kafka 0. I'm really. Additionally, we'll use this API to implement transactional. Consumers only get the messages that they’ve subscribed to, versus having to filter at the receiving end. Consumer Groups and Partitions. Apache Kafka - Simple Producer Example - Let us create an application for publishing and consuming messages using a Java client. Failed To Construct Kafka Consumer Spring Boot. A single Kafka cluster is enough for local developments. Broker sometimes refer to more of a logical system or as Kafka as a whole. Confluent Platform includes client libraries for multiple languages that provide both low-level access to Apache Kafka® and higher level stream processing. Kafka does not deletes consumed messages with its default settings. The Spring for Apache Kafka (spring-kafka) project applies core Spring concepts to the development of Kafka-based messaging solutions. There are many reasons why Apache Kafka is being adopted and used more widely today. People who worked with kafka-python or Java Client probably know that the poll() API is designed to ensure liveness of a Consumer Group. Thanks to the combination of: Kubernetes Minikube The Yolean/kubernetes-kafka GitHub Repo with Kubernetes yaml files that creates allRead More. In addition to having Kafka consumer properties, other configuration properties can be passed here. An interesting use case that has emerged is the microservices architecture. Consumers are the programs which consumes the given data with offsets. Kafka does not offer the ability to delete. You can go for Kafka if the data will be consumed by multiple applications. Import source code into Eclipse. For convenience I copied essential terminology definitions directly from Kafka documentation:. I am looking to setup multiple listeners on a kafka topic inside my application. This book will show you how to use Kafka efficiently, and contains practical solutions to the common problems that. It needs resources to make the content available and host the website. Solace’s hierarchical topic structure (multiple levels, delimited by slash /) and wildcard ability allows for much more fine-grained filtering at the broker than you may be able to get with a Kafka broker. This Mechanism is called SASL/PLAIN. Prerequisite :- . We also need the DTO module. Consumers can fetch offsets by reading from this topic (although we provide an in-memory offsets cache for faster access). Through RESTful API in Spring Boot we will send messages to a Kafka topic through a Kafka Producer. while running consumer on multiple multiple machines ,only a single consumer recieves messages and not the others. Schema Registry Serializer and Formatter¶. Consumers can also read from unique partitions within consumer groups so that an entire topic can be consumed. Consumer Friendly It is possible to integrate with the variety of consumers using Kafka. application. We explored a few key concepts and dove into an example of configuring spring-Kafka to be a producer/consumer client. We will also be using a Java based Kafka Consumer using Kafka Consumer API to consume and print the messages sent from the Spring Boot application. 11 release, thereby eliminating the need for application developers to code the important feature themselves. KafkaConsumer class with a set of properties, that looks like: consumer = new KafkaConsumer(properties); In this example, the properties are externalized in a file, with the following entries:. Receiving messages from a topic joining a consumer group. Subject: How to Mock Kafka Consumer Endpoint with Spock Framework Unit Test cases Hi, I am using Spock Framework to perform Unit Testing of Camel Routes. The Consumer Group name is global across a Kafka cluster, so you should be careful that any 'old' logic Consumers be shutdown before starting new code. Read more about streams here. New requests are queued to one of the multiple queues in an event server instance, which is then processed by multiple parallel Kafka producer threads. 2 Console Producers and Consumers Follow the steps given below….