Book Image

Apache Kafka Quick Start Guide

By : Raúl Estrada
Book Image

Apache Kafka Quick Start Guide

By: Raúl Estrada

Overview of this book

Apache Kafka is a great open source platform for handling your real-time data pipeline to ensure high-speed filtering and pattern matching on the ?y. In this book, you will learn how to use Apache Kafka for efficient processing of distributed applications and will get familiar with solving everyday problems in fast data and processing pipelines. This book focuses on programming rather than the configuration management of Kafka clusters or DevOps. It starts off with the installation and setting up the development environment, before quickly moving on to performing fundamental messaging operations such as validation and enrichment. Here you will learn about message composition with pure Kafka API and Kafka Streams. You will look into the transformation of messages in different formats, such asext, binary, XML, JSON, and AVRO. Next, you will learn how to expose the schemas contained in Kafka with the Schema Registry. You will then learn how to work with all relevant connectors with Kafka Connect. While working with Kafka Streams, you will perform various interesting operations on streams, such as windowing, joins, and aggregations. Finally, through KSQL, you will learn how to retrieve, insert, modify, and delete data streams, and how to manipulate watermarks and windows.
Table of Contents (10 chapters)

Using the KSQL CLI

The KSQL CLI is a command prompt to interact with KSQL; it is very similar to the one that comes with relational databases such as MariaDB or MySQL. To see all the possible commands, type help and a list with the options will be displayed.

At the moment, we have not informed KSQL of anything. We must declare that something is a table or a stream. We will use the information produced from previous chapters with the producers that write JSON information to the healthchecks topic.

If you remember, the data looks like this:

{"event":"HEALTH_CHECK","factory":"Lake Anyaport","serialNumber":"EW05-HV36","type":"WIND","status":"STARTING","lastStartedAt":"2018-09-17T11:05:26.094+0000","temperature":62.0,"ipAddress":"15.185.195...