Book Image

Mastering Symfony

Book Image

Mastering Symfony

Overview of this book

In this book, you will learn some lesser known aspects of development with Symfony, and you will see how to use Symfony as a framework to create reliable and effective applications. You might have developed some impressive PHP libraries in other projects, but what is the point when your library is tied to one particular project? With Symfony, you can turn your code into a service and reuse it in other projects. This book starts with Symfony concepts such as bundles, routing, twig, doctrine, and more, taking you through the request/response life cycle. You will then proceed to set up development, test, and deployment environments in AWS. Then you will create reliable projects using Behat and Mink, and design business logic, cover authentication, and authorization steps in a security checking process. You will be walked through concepts such as DependencyInjection, service containers, and services, and go through steps to create customized commands for Symfony's console. Finally, the book covers performance optimization and the use of Varnish and Memcached in our project, and you are treated with the creation of database agnostic bundles and best practices.
Table of Contents (17 chapters)
Mastering Symfony
Credits
About the Author
About the Reviewers
Index

Chapter 9. Services and Service Containers

Imagine that you are in charge of maintaining a legacy code and you find a couple of classes, with over 1,000 lines of code each, which have a long list of variables, constants, methods, and so on. What a mess; even reading that code takes ages, let alone understanding and maintaining it.

You might think, okay, I can break down those big classes into, say, 10 smaller ones and instantiate them in the main class. This helps a little, but it still wastes a lot of memory and, more importantly, it is hard to test and maintain them because they are tightly coupled to each other.

So what is the solution? The best way to deal with situations like this (or implementing a big project from scratch) is to read and understand the business requirements first and assemble a list of functionality for that application. Then, create one class for each functionality. It is totally fine if a feature consists of multiple functionality but before implementing that feature...