Book Image

Redis 4.x Cookbook

Book Image

Redis 4.x Cookbook

Overview of this book

Redis is considered the world's most popular key-value store database. Its versatility and the wide variety of use cases it enables have made it a popular choice of database for many enterprises. Based on the latest version of Redis, this book provides both step-by-step recipes and relevant the background information required to utilize its features to the fullest. It covers everything from a basic understanding of Redis data types to advanced aspects of Redis high availability, clustering, administration, and troubleshooting. This book will be your great companion to master all aspects of Redis. The book starts off by installing and configuring Redis for you to get started with ease. Moving on, all the data types and features of Redis are introduced in detail. Next, you will learn how to develop applications with Redis in Java, Python, and the Spring Boot web framework. You will also learn replication tasks, which will help you to troubleshoot replication issues. Furthermore, you will learn the steps that need to be undertaken to ensure high availability on your cluster and during production deployment. Toward the end of the book, you will learn the topmost tasks that will help you to troubleshoot your ecosystem efficiently, along with extending Redis by using different modules.
Table of Contents (21 chapters)
Title Page
Packt Upsell
Windows Environment Setup

Debugging Lua

Debugging allows you to detect, diagnose, and eliminate errors in a program. Generally speaking, debugging a program involves logic checking and variable-value viewing. For Lua in Redis, a debugging tool was introduced in version 3.2 to make the debugging process much easier, and there are some functions that can help you to print logs for debugging. In this recipe, we'll see how to achieve these debugging steps in Redis.

Getting ready…

You need to finish the installation of the Redis Server as we described in the Downloading and installing Redis recipe in Chapter 1, Getting Started with Redis.

For logging in Redis, you have to set the following configurations in redis.conf:

logfile "/redis/log/redis.log" 
loglevel debug

Then, you can start the Redis Server with the configuration file, as we have shown in the Starting and shutting down Redis recipe in Chapter 1, Getting Started with Redis.

How to do it...

Let's take the Lua script introduced in the previous recipe to show how to debug...