Redis Essentials

Maxwell Dayvson Da Silva, Hugo Lopes Tavares

• Publisher: Packt Publishing
• Year: 2015
• eBook ISBN: 9781784392451
• Edition: 1
• Topic: Computer Science
• Subtopic: Databases
• Index: Computer Science

Harness the power of Redis to integrate and manage your projects efficiently

About This Book

• Learn how to use Redis's data types efficiently to manage large data sets
• Scale Redis to multiple servers with Twemproxy, Redis Sentinel, and Redis Cluster
• A fast-paced guide, full of real-world examples to help you get the best out of the features offered by Redis

Who This Book Is For

If you are a competent developer with experience of working with data structure servers and want to boost your project's performance by learning about features of Redis, then this book is for you.

What You Will Learn

• Build analytics applications using Bitmaps and Hyperloglogs
• Enhance scalability with Twemproxy, Redis Sentinel, and Redis Cluster
• Build a Time Series implementation in Node.js and Redis
• Create your own Redis commands by extending Redis with Lua
• Get to know security techniques to protect your data (SSL encryption, firewall rules, basic authorization)
• Persist data to disk and learn the trade-offs of AOF and RDB
• Understand how to use Node.js, PHP, Python, and Ruby clients for Redis
• Avoid common pitfalls when designing your next solution

In Detail

Redis is the most popular in-memory key-value data store. It's very lightweight and its data types give it an edge over the other competitors. If you need an in-memory database or a high-performance cache system that is simple to use and highly scalable, Redis is what you need.

Redis Essentials is a fast-paced guide that teaches the fundamentals on data types, explains how to manage data through commands, and shares experiences from big players in the industry.

We start off by explaining the basics of Redis followed by the various data types such as Strings, hashes, lists, and more. Next, Common pitfalls for various scenarios are described, followed by solutions to ensure you do not fall into common traps.

After this, major differences between client implementations in PHP, Python, and Ruby are presented. Next, you will learn how to extend Redis with Lua, get to know security techniques such as basic authorization, firewall rules, and SSL encryption, and discover how to use Twemproxy, Redis Sentinel, and Redis Cluster to scale infrastructures horizontally. At the end of this book, you will be able to utilize all the essential features of Redis to optimize your project's performance.

Style and approach

A practical guide that offers the foundation upon which you can begin to understand the capabilities of Redis using a step-by-step approach. This book is full of real-world problems and in-depth knowledge of the concepts and features of Redis, with plenty of examples.

Redis Essentials

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Table of Contents

Redis Essentials

Credits

About the Authors

Acknowledgments

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the example code

Errata

Piracy

Questions

1. Getting Started (The Baby Steps)

Installation

Installing from source

Hello Redis (command-line interface examples)

Installing Node.js

JavaScript syntax quick reference guide

Hello World with Node.js and Redis

Redis data types

Strings

String examples with redis-cli

Building a voting system with Strings using Node.js

Lists

List examples with redis-cli

Implementing a generic Queue System

Hashes

Using Hashes with redis-cli

A voting system with Hashes and Node.js

Summary

2. Advanced Data Types (Earning a Black Belt)

Sets

Set examples with redis-cli

Building a deal tracking system

Sorted Sets

Sorted Set examples with redis-cli

Building a leaderboard system for an online game

Bitmaps

Bitmap examples with redis-cli

Building web analytics

HyperLogLogs

Counting unique users – HyperLogLog versus Set

HyperLogLogs examples with redis-cli

Counting and retrieving unique website visits

Summary

3. Time Series (A Collection of Observations)

Building the foundation

Optimizing with Hashes

Adding uniqueness with Sorted Sets and HyperLogLog

Summary

4. Commands (Where the Wild Things Are)

Pub/Sub

Transactions

Pipelines

Scripting

Lua syntax basics

Redis meets Lua

Miscellaneous commands

INFO

DBSIZE

DEBUG SEGFAULT

MONITOR

CLIENT LIST and CLIENT SET NAME

CLIENT KILL

FLUSHALL

RANDOMKEY

EXPIRE and EXPIREAT

TTL and PTTL

PERSIST

SETEX

DEL

EXISTS

PING

MIGRATE

SELECT

AUTH

SCRIPT KILL

SHUTDOWN

OBJECT ENCODING

Data type optimizations

String

List

Set

Hash

Sorted Set

Measuring memory usage

Summary

5. Clients for Your Favorite Language (Become a Redis Polyglot)

PHP

The basic commands in PHP

The blocking commands in PHP

Pipelines in PHP

Transactions in PHP

Scripting in PHP

Python

The basic commands in Python

The blocking commands in Python

Pipelines in Python

Transactions in Python

Scripting in Python

Ruby

The basic commands in Ruby

The blocking commands in Ruby

Pipelines in Ruby

Transactions in Ruby

Scripting in Ruby

Summary

6. Common Pitfalls (Avoiding Traps)

The wrong data type for the job

The Set approach

The Bitmap approach

Multiple Redis databases

Keys without a namespace

Using Swap

Not planning and configuring the memory properly

An inappropriate persistence strategy

Summary

7. Security Techniques (Guard Your Data)

The basic security

Obfuscating critical commands

Networking security

Protecting Redis with firewall rules

Running Redis on the loopback network interface

Running Redis in a Virtual Private Cloud

Encrypting client-to-server communication

Running stunnel on both the server and the client

Running stunnel on the server and using a Redis client that supports SSL

Summary

8. Scaling Redis (Beyond a Single Instance)

Persistence

RDB (Redis Database)

AOF (Append-only File)

RDB versus AOF

Replication

Partitioning

Range partitioning

Hash partitioning

Presharding

Consistent hashing

Tagging

Data store versus cache

Implementations of Redis partitioning

Automatic sharding with twemproxy

Other architectures that use twemproxy

Summary

9. Redis Cluster and Redis Sentinel (Collective Intelligence)

The CAP theorem

Redis Sentinel

The basic Sentinel configuration

Connecting to Sentinel

Network partition (split-brain)

Redis Cluster

Hash slots

Hash tags

Creating a basic cluster

Finding nodes and redirects

Configuration

Different Redis Cluster architectures

Cluster administration

Creating a cluster

Adding slaves/replicas

Scaling reads using slave nodes

Adding nodes

Removing nodes

Redis Cluster administration using the redis-trib tool

Summary

Index

Redis Essentials

Copyright © 2015 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the authors, nor Packt Publishing, and its dealers and distributors will be held liable for any damages caused or alleged to be caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

First published: September 2015

Production reference: 1030915

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-78439-245-1

www.packtpub.com

Credits

Authors

Maxwell Dayvson Da Silva

Hugo Lopes Tavares

Reviewers

Gustavo Franco

Chad Lung

Stephen McDonald

Yi Wang

Comm...

Table of contents

• Redis Essentials