Introducing Redis Stack

Redis has achieved several important milestones since its inception in 2009, from taking the lead as the most popular key-value data store, according to the ranking published every month by the website DB-Engines (and the sixth among all database systems), up to establishing the record as the most downloaded container image on Docker. Not to mention that Redis has been the most loved database for five years in a row, according to the Developer Survey published by Stack Overflow in the years 2016-2021. And, for sure, you, or a friend of yours, have used it for some reason, work, or hobby.

If you are reading this book, chances are you have programmed an application using a Redis server, or at least you know what it is and what it is used for. In this chapter, we’ll recap what made Redis the most famous caching system in the world and we’ll share some anecdotes about the development undertaken by its creator, Salvatore Sanfilippo. We won’t stay long on the story of Redis, though, because this book is about application modernization. As you read through, you will discover how the original database, designed for speed and simplicity, has evolved to resolve many of the new challenges of this age, without compromising on the ease of adoption, flexibility, and, above all, speed.

Redis Stack is an extension of Redis presented in 2022, which introduces JSON, vector, and time series data modeling capabilities, all supporting real-time queries and searches. Redis Stack represents a new approach to providing a rich data modeling experience all within the same database server. It introduces features such as vector similarity search to query structured and unstructured data (for example, text, images, or audio files) and delivers probabilistic Bloom filters to efficiently resolve recurrent big data problems. Redis Stack is also a data platform that supports event-driven programming and introduces stream processing features. By the end of this chapter, you will understand what Redis Stack is and how it enhances the Redis server with many new capabilities. Above all, you will learn the motivation behind Redis Stack and why multi-model databases can increase the speed of technological innovation for organizations of all sizes. In this chapter, we are going to cover the following topics:

• Exploring the history of Redis
• The open source project
• From key-value to multi-model real-time databases
• Redis Stack deployment types