Book Image

The Art of Modern PHP 8

By : Joseph Edmonds
5 (1)
Book Image

The Art of Modern PHP 8

5 (1)
By: Joseph Edmonds

Overview of this book

PHP has come a long way since its introduction. While the language has evolved with PHP 8, there are still a lot of websites running on a version of PHP that is no longer supported. If you are a PHP developer working with legacy PHP systems and want to discover the tenants of modern PHP, this is the book for you. The Art of Modern PHP 8 walks you through the latest PHP features and language concepts. The book helps you upgrade your knowledge of PHP programming and practices. Starting with object-oriented programming (OOP) in PHP and related language features, you'll work through modern programming techniques such as inheritance, understand how it contrasts with composition, and finally look at more advanced language features. You'll learn about the MVC pattern by developing your own MVC system and advance to understanding what a DI container does by building a toy DI container. The book gives you an overview of Composer and how to use it to create reusable PHP packages. You’ll also find techniques for deploying these packages to package libraries for other developers to explore. By the end of this PHP book, you'll have equipped yourself with modern server-side programming techniques using the latest versions of PHP.
Table of Contents (19 chapters)
Section 1 – PHP 8 OOP
Free Chapter
Chapter 1: Object-Oriented PHP
Section 2 – PHP Types
Chapter 5: Object Types, Interfaces, and Unions
Section 3 – Clean PHP 8 Patterns and Style
Section 4 – PHP 8 Composer Package Management (and PHP 8.1)
Section 5 – Bonus Section - PHP 8.1

Version constraints

When we require a package in our composer.json file, we also have to define a "version constraint." This instructs Composer on exactly what versions are acceptable to be installed.

The most flexible option is to specify * as the version constraint, which means "anything." It will still respect the configured minimum stability but beyond that, anything goes. This is generally a terrible idea as things could change wildly from one version to the next when you update packages, breaking your application in weird and wonderful ways.

Instead, we always want to specify some kind of constraint. When we call composer require, Composer will calculate a constraint for us. You can see these in the composer.json file we created in MyFirstProject:

    "monolog/monolog": "^2.2",
    "php-di/php-di": "^6.3"

What Composer has used here is what is called the "Caret...