Drupal 9

Whilst Twig is a powerful tool in its own right there are occasions when you need to pull out data from Drupal or manipulate it in certain ways. I normally do this using preprocess steps, but I recently found that it was also possible to extend Twig within the Drupal framework to provide your own functions and filters. This can be useful if you have custom templates and need to perform special actions on data items to format them in different ways.

Setting Up

Before we can create Twig filters and functions in Drupal we need to tell Drupal that we have a class that contains them. This is done by creating an entry in the your module services file that contains the tag tag.extension. In a module called "custom_twig" the file would be called custom_twig.services.yml and would contain the following.

I like working with DrupalVM and I've worked with Ansible based Vagrant setups for years and so I'm very familiar with it's setup. More than that, I find I have very few problems with running it. I normally run it with Vagrant, but you can run it with Docker if you like.

When starting a new site project I normally add DrupalVM to the codebase so that I can get the site up and running quickly. This is especially useful if something like Solr is involved as setting that up is a pain. I thought I would go through the steps involved in adding DrupalVM to your codebase as it's pretty simple and will get you up and running with a Drupal site in about 10 minutes.

Start out with a Drupal site in a composer setup. I normally run the Drupal recommended composer setup file so that I have a up to date Drupal codebase, so let's do that here.

According to the official Drupal documentation, to create a new site using composer you should use a composer template project called drupal/recommended-project. This has a default composer.json file setup with some values that will help you get up and running swiftly with a new Drupal project.

It's a good initiative to get you up and running with a standard Drupal site pretty quickly. I've used this composer project a number of times now, but I haven't really looked at what's in it. I thought I would dive in and see exactly that's in there and dissect it line by line.

To reiterate what's in the Drupal documentation, to create a brand new Drupal project using composer use the following command.

Installing a Drupal site from configuration is useful when running tests or if you don't have a copy of the database. You'll get a copy of the Drupal site without any content that will act in the same way as the live site. You can use modules like default content to add content into the mix so your newly installed site acts a little bit more like the live version.

Since there are some prerequisites to get this up and running I thought I would run through what is needed to get this working and how to run it.

A change that was snuck into Drupal version 8.8.0 and wasn't mentioned in the 8.8.0 change notes was a small change to the setting that controls the placement of the configuration directories. The alteration deprecated the $config_directories setting from the settings.php file and move the configuration into the $settings array. You can see the detail behind this change on the Drupal change record.

The fix for this is very easy and only needs a single line of code to change in your settings file.

Change this:

$config_directories['sync'] = '../config/sync';

To this:

Drupal 9 will be released on June 3rd, 2020 so with this just around the corner I thought I'd put together a post about how to check if your site is ready. The transition from Drupal 7 to Drupal 8 was more of an upheaval than an upgrade. Updating a Drupal 7 site to Drupal 8 requires a lot of effort involving code changes and migration steps. Drupal 7 modules are not compatible with Drupal 8 and so any custom code written needs to be adapted to the new structure of Drupal. The difficulty of this change made the Drupal community take notice and think about how future versions of Drupal are introduced.

For a long time the drupal_set_message() function has been a mainstay of Drupal development. You can use this function to print a message or an error response to a user. This is useful to do as it can be done almost anywhere before the final page rendering functions and will be printed into the same area of a Drupal page.

This has recently been deprecated in Drupal 8.5.0 and so I was looking around on how to do the same thing in a new way. Drupal now has a messenger service, powered by the class Drupal\Core\Messenger\Messenger. This can be included into your code using the following shortcut.

$messenger = \Drupal::messenger();

This can be used to print messages to the user. For example, to print a standard message with a blue background do the following.

$messenger->addMessage('Message printed to a user.');

This can be done in one line like this.

I recently wrote a post about setting up a multi-site configuration setup using the Configuration Split module. That post was written after I did research into how to set up configuration splits and use them to create multi-site setups in Drupal. One thing I realised when doing that research was that although it's quite easy to get setup with that kind of setup, it's also easy to get it wrong and create a setup that really doesn't work.

Setting up a Drupal 8 site for a multi-site environment with a common configuration isn't too hard, it just requires a little bit of forethought and some planning to get things right. You need to have a default configuration in mind, and then think about how each site can override this configuration in different ways. I have seen it done wrong a few times recently and once you go down the wrong path, getting things back in line again can be a difficult.

The default configuration covers things like content types, vocabularies, fields, views, enabled modules, or anything else that would make up the structure of the site. Each sub-site would override this by adding configuration for theme components, custom block placement, or anything else that is custom to that site.