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

Custom Views argument

When we first exposed the player and team data to Views, we used an argument plugin so that we could have a contextual filter on the team ID a player belongs to. To do this, we used the existing numeric plugin on the actual team_id field of the players table. But what if we wanted an argument that works on more levels? For example, we don't exactly know what kind of data we'll receive, but we want to be able to handle nicely both a numeric one (team ID) and a textual one (team name). All in one argument. To achieve this, we can create a simple ViewsArgument plugin to handle this for us.

First thing, like always, is to define this field. We don't want to mess with the team_id field onto which we added the earlier argument as that can still be used. Instead, we'll create a new field, this time on the teams table, which we will simply call team:

$data['teams']['team'] = [ 
  'title' => t('Team...