Book Image

Drupal 8 Module Development - Second Edition

By : Daniel Sipos
Book Image

Drupal 8 Module Development - Second Edition

By: Daniel Sipos

Overview of this book

Drupal 8 comes with a release cycle that allows for new functionality to be added at a much faster pace. However, this also means code deprecations and changing architecture that you need to stay on top of. This book updates the first edition and includes the new functionality introduced in versions up to, and including 8.7. The book will first introduce you to the Drupal 8 architecture and its subsystems before diving into creating your first module with basic functionality. You will work with the Drupal logging and mailing systems, learn how to output data using the theme layer and work with menus and links programmatically. Then, you will learn how to work with different kinds of data storages, create custom entities, field types and leverage the Database API for lower level database queries. You will further see how to introduce JavaScript into your module, work with the various file systems and ensure the code you write works on multilingual sites. Finally, you will learn how to programmatically work with Views, write automated tests for your functionality and also write secure code in general. By the end, you will have learned how to develop your own custom module that can provide complex business solutions. And who knows, maybe you’ll even contribute it back to the Drupal community. Foreword by Dries Buytaert, founder of Drupal.
Table of Contents (20 chapters)

Batches, Queues, and Cron

If in the previous chapter we kept things a bit more theoretical with me throwing "rules" at you, in this chapter I am going to make up for it and we are going to have some fun. This means we are going to write some code that demonstrates concepts related to data processing, especially larger amounts of it. And in doing so, we are going to cover a few topics.

First, we are going to look back at the hook_update_N() hook we saw in Chapter 8, The Database API. More specifically, we are going to see how the &$sandbox parameter can be used in order to handle updates that need to process some data that may take a bit longer and should be split across multiple requests. Next up, we are going to look at standalone batches (which basically use the same system) to process data in batches across multiple requests. And what better example to illustrate...