Book Image

Drupal 9 Module Development - Third Edition

By : Daniel Sipos
Book Image

Drupal 9 Module Development - Third Edition

By: Daniel Sipos

Overview of this book

With its latest release, Drupal 9, the popular open source CMS platform has been updated with new functionalities for building complex Drupal apps with ease. This third edition of the Drupal Module Development guide covers these new Drupal features, helping you to stay on top of code deprecations and the changing architecture with every release. The book starts by introducing you to the Drupal 9 architecture and its subsystems before showing you how to create your first module with basic functionality. You’ll explore the Drupal logging and mailing systems, learn how to output data using the theme layer, and work with menus and links programmatically. Once you’ve understood the different kinds of data storage, this Drupal guide will demonstrate how to create custom entities and field types and leverage the Database API for lower-level database queries. You’ll also learn how to introduce JavaScript into your module, work with various file systems, and ensure that your code works on multilingual sites. Finally, you’ll work with Views, create automated tests for your functionality, and write secure code. By the end of the book, you’ll have learned how to develop custom modules that can provide solutions to complex business problems, and who knows, maybe you’ll even contribute to the Drupal community!
Table of Contents (20 chapters)
3
Chapter 3: Logging and Mailing

Content entities and the Translation API

So far in this chapter, we've mostly talked about how to ensure that our modules output only text that can also be translated. The Drupal best practice is to always use these techniques regardless of whether the site is multilingual. You never know whether you'll ever need to add a new language.

In this section, we are going to talk a bit about how we can interact with the language system programmatically and work with entity translations.

A potentially important thing you'll often want to do is check the current language of the site. Depending on the language negotiation in place, this can either be determined by the browser language, a domain, a URL prefix, or others. The LanguageManager is the service we use to figure this out. We can inject it using the language_manager key or use it via the static shorthand:

$manager = \Drupal::languageManager();  

To get the current language, we do this:

$language...