Book Image

Yii2 Application Development Cookbook - Third Edition

By : Sergey Ivanov, Andrew Bogdanov, Dmitry Eliseev
Book Image

Yii2 Application Development Cookbook - Third Edition

By: Sergey Ivanov, Andrew Bogdanov, Dmitry Eliseev

Overview of this book

Yii is a free, open source web application development framework written in PHP5 that promotes clean DRY design and encourages rapid development. It works to streamline your application development time and helps to ensure an extremely efficient, extensible, and maintainable end product. Being extremely performance optimized, Yii is a perfect choice for any size project. However, it has been built with sophisticated, enterprise applications in mind. You have full control over the configuration from head-to-toe (presentation-to-persistence) to conform to your enterprise development guidelines. It comes packaged with tools to help test and debug your application, and has clear and comprehensive documentation. This book is a collection of Yii2 recipes. Each recipe is represented as a full and independent item, which showcases solutions from real web-applications. So you can easily reproduce them in your environment and learn Yii2 fast and without tears. All recipes are explained with step-by-step code examples and clear screenshots. Yii2 is like a suit that looks great off the rack, but is also very easy to tailor to fit your needs. Virtually every component of the framework is extensible. This book will show how to use official extensions, extend any component, or write a new one. This book will help you create modern web applications quickly, and make sure they perform well using examples and business logic from real life. You will deal with the Yii command line, migrations, and assets. You will learn about role-based access, security, and deployment. We’ll show you how to easily get started, configure your environment, and be ready to write web applications efficiently and quickly.
Table of Contents (19 chapters)
Yii2 Application Development Cookbook Third Edition
About the Authors
About the Reviewer

Customizing Captcha

A standard Yii Captcha is good enough to protect you from spam, but there are situations where you may want to customize it, such as the following:

  • You face a spam bot that can read image text and you need to add more security

  • You want to make it more interesting or easier to enter the Captcha text

In our example, we will modify Yii's Captcha so it will require the user to solve a really simple arithmetic puzzle instead of just repeating the text in an image.

Getting ready

As a starting point for this example, we will take the result of the Adding and customizing CaptchaWidget recipe. Alternatively, you can take any form that uses Captcha, as we are not modifying the existing code a lot.

How to do it...

We need to customize CaptchaAction, which generates the code and renders its image representation. The code should be a random number and the representation should be an arithmetic expression that gives the same result:

  1. Create an @app/components/MathCaptchaAction.php action...