Of the 3 main components of the field system -- types, widgets and formatters -- only 1 has an impact on the actual display of content for end users: field formatters. Field formatters are responsible for taking the data stored by a field and transforming it into the markup that is sent to the browser when an end user views your site.
In this tutorial we'll:
- Look at the role field formatters play in the Field API
- Identify the main components that make up a field formatter
By the end of this tutorial you should be able to define the role of a field formatter plugin.
Drupal's field system provides us with a flexible system of adding different types of discrete data to content types. This enables us to create rich content models. The Field API allows us to define these distinct field types by creating a new plugin. These plugins specify a FieldType
attribute. In this tutorial, we'll look at these attributes in detail. We'll look at the implementations of field types from Drupal core. Also, we'll see what a new custom field type would look like.
By the end of this tutorial, you should be able to:
- Understand how field type definitions are created and exposed to Drupal
- Identify the various field types provided by Drupal core
- Understand the requirements for providing a specification for a new field type
Once we've explored the various field types provided by Drupal core, the next component of the Field API to explore is field widgets. Field widgets define how the data structure of the field is displayed on an edit form. When content editors interact with your field type they will be doing so via the field widget you provide. In this tutorial, we'll take a look at the field widgets provided by Drupal core, the plugin type required to define our own custom widget and how we can define multiple widget options for a single field type.
By the end of this tutorial, you should be able to:
- Understand where field widgets fit into the overall Field API
- Implement a custom field widget to support a particular field type
In their simplest form layout plugins in Drupal Layout Builder define the part of the content output that can't be changed. For example a three column layout will consist of three equal columns every time an editor decides to use it as the layout section. The editor can place whatever they want into the three columns. But they can not change the overall layout. This restricts editorial capabilities of using layout plugins since in real life a three column layout may need to consist of a wider middle column and narrower side columns, allow for column headings, or other customizations.
This flexibility is accomplished by creating, and exposing, configuration options for layout plugins in Drupal's Layout Builder. In more advanced cases, we can take this flexibility further by exposing an interface editors to dynamically define layout plugins.
In this tutorial we'll:
- Learn how to use custom PHP classes in the layout plugin annotation
- Learn what annotations properties can be used for custom layout declaration
- Define the concept of derivatives and outline scenarios for using them
- How to declare static single layouts using YAML format
By the end of this tutorial you'll learn advanced ways of declaring configurable custom layout plugins.
Layout plugins can be dynamically generated based on configuration using plugin derivatives. This allows developers to provide Drupal site administrators with a UI for creating new layout plugins, or to automatically register layout plugins based on the environment.
This is useful in situations where it's not enough to define a set of pre-configured layouts to use in the Layout Builder. Instead, you need to empower editors to declare their own new layout plugins without writing any code. Derivatives could also be used in scenarios where the layouts that should be made available depend on configuration set elsewhere in the module. Or, you might have a scenario where you want to have multiple different 2-column layouts, and for those layouts to have different names, so that they can be themed differently depending on which one is used.
In this tutorial we'll:
- Create a user interface that allows editors to dynamically define layouts via configuration.
- Learn how to set up a plugin deriver that creates layout plugins based on configuration.
- Create custom dynamic layout plugins with variable numbers of columns.
By the end of this tutorial you'll know how to declare dynamic custom layout plugins using derivatives.
When defining new layout plugins for Drupal you can add custom CSS and JavaScript via asset libraries. This allows for the creation of layouts with complex structures and interactive elements. Those elements might include grids, tabs, and accordions. Drupal allows you to attach custom CSS and JavaScript directly to a layout plugin, or via the layout's Twig template file.
In this tutorial we'll:
- Define a custom asset library with JavaScript and CSS functionality
- Attach the asset library to the custom layout plugin
- Transform a multicolumn layout into tabs
By the end of this tutorial you should know how to attach custom CSS and JavaScript to a layout plugin to add interactivity and styling.
When building a site using Drupal's Layout Builder, it's a good idea to keep the number of layout plugins manageable. In many cases it's better to create a single layout plugin that can be re-used rather than duplicate a layout multiple times to accommodate minor variations. One way to do this is to provide editors with configuration options that will change the output when a layout is used.
For example, imagine you need to provide variations of a 3-column layout where the columns are different widths. You could define a new layout for each variation. Or you could define a single layout with a configuration option that allows a user to choose the column widths. The latter approach reduces code duplication, and makes the codebase easier to maintain.
In this tutorial we'll:
- Learn how to declare advance layout plugins with configurable settings in the Drupal Layout Builder
- Extend the
LayoutDefault
class and create a custom settings form that editors will see when using a layout - Use the provided configuration values in the layout's Twig template file to modify the layout when it is rendered
By the end of this tutorial you should be able to expose layout-related settings to editors, allowing for more flexibility in custom layout plugins.
Drupal site administrators can create new media entity types, with their own unique configurations and sets of associated fields. Different media types can be configured with different field names, permissions, moderation workflows, and display settings, making it possible to create truly custom content administration experiences. The process is similar to creating a node content type like articles or events with one major distinction: every media type inherits from a specific media source plugin. The source plugin provides domain-specific knowledge about the kind of resource being represented. For example, the Remote video source plugin used with the default Remote video media type knows how to consume and display videos from YouTube and Vimeo given only their URL.
Drupal core comes with a couple of common media source plugins, and contributed modules and custom code can add to this list, increasing the different media providers with which Drupal can integrate.
In this tutorial we'll learn how to:
- Install a contributed module that provides a new media source plugin.
- Create a new media type.
By the end of this tutorial you should be able to explain how source plugins relate to media types, and create a new media type.
The Drupal Media Library and Media ecosystem can be integrated with any third-party media provider by defining new media source plugins. Media types (Media entity bundles) have an important distinction compared to other content entity types like nodes. Every media type inherits from a specific media source plugin. The source plugin provides domain-specific knowledge about the kind of resource being represented. For example, media types dealing with images know how to validate file extensions and render <img>
tags. Media types dealing with remotely hosted videos might know how to retrieve thumbnails from a remote API, and display an HTML video player and transcript.
In this tutorial we'll learn how to:
- Define a new source plugin
- Integrate a third-party API via its existing PHP library
By the end of this tutorial you should be able to create a new source plugin that exposes any third-party media resources you want to integrate with Drupal.
If the Media assets you want to use in your library support oEmbed, then you might be able to use them with a minimal custom code. Before you go down the path of creating a custom media source plugin try this approach first.
oEmbed is a standard way of allowing third party sites to embed an asset represented by a URL. The Remote Video source in core uses the oEmbed features of YouTube and Vimeo. When you paste a link into a Slack channel, and it displays a pretty card preview, or an embedded video or Spotify playlist, that's oEmbed in action. Does the Media you want to embed have a canonical URL? If so, paste it into the tool here and see if it displays oEmbed info in the results.
In this tutorial we'll:
- Learn how to enable additional oEmbed providers as Media sources
- Use the contributed oEmbed Providers module for compatible providers
- Demonstrate how to create a custom oEmbed media source plugin to further customize the results
By the end of this tutorial you should be able to embed any oEmbed-compatible content as Media assets in Drupal.
Often, there's an existing Drush command that does most of what you want, but needs just a few tweaks or enhancements to make it meet your project requirements. Maybe the existing core Drush command has the functionality but lacks some additional validation. Or maybe you need to add an option to perform some application-specific debugging logic for all commands in a group.
Drush hooks can be used to alter, extend, and enhance existing Drush commands.
In this tutorial we'll:
- Learn how to alter a Drush command with code in a custom module
- Declare a validation hook that alters the
user:password
command with additional password validation logic
By the end of this tutorial you should be able to alter a Drush command provided by Drush core or a contributed module with your own custom code.
Back-end developers, and Drupal site builders, often find themselves having to perform the same UI steps over and over again, like exporting configuration, importing configuration changes, running cron, processing a large queue of jobs, indexing items for Search API, and more. Performing these tasks with Drush saves time and reduces the number of clicks required.
Drush core contains commands to execute all the most common tasks. Many contributed modules provide their own Drush commands to make interaction with the module's features, easier, faster, and scriptable.
In this tutorial we'll:
- Learn about the Drush core commands for common tasks like interacting with queues, performing database backups, and importing/exporting configuration
- Demonstrate how to find the Drush commands provided by contributed modules in your project
By the end of this tutorial you'll learn some popular commands for common tasks that'll speed up your daily work.
Every Drupal site consists of many Drupal projects like modules and themes. Drush comes with a group of commands that aid in managing projects from the command line. These commands can check which modules are present in a site's codebase, report their security status, enable modules, and display metadata for modules and themes. All of these commands start with the pm
prefix, and are part of the project manager group.
Common use cases for the project manager commands include: quickly enabling/disabling modules via the CLI rather than performing numerous clicks in the UI, and as part of CI/CD process that lists (or maybe even automates) security updates.
In this tutorial we'll:
- List the available
pm
commands - Enable a module with Drush
- Uninstall a module with Drush
- Use Drush to check for security updates for modules, themes and PHP packages
By the end of this tutorial you'll have an understanding of the project manager commands that come with Drush, how to use them, and how to speed up common workflows and maintenance tasks.
Administration and maintenance of Drupal websites consists of many tasks that can both be performed via the command line, and automated, with Drush. Using Drush's site and environment administration commands you can run database updates, check an environment's status, clear (rebuild) the cache, perform Cron-related operations, and manage users. These tasks are repetitive, often require many steps in the UI, and may be tedious in the long run. Learning to execute them with Drush can save you time and allows for more automation of common tasks.
In this tutorial we'll:
- Use Drush to check a site's status
- Learn how to perform database updates with Drush
- Clear the Drupal cache with Drush
- Use Drush to execute Cron tasks for a Drupal site
- Learn how to use Drush to login to a site as any user, and manage existing users
By the end of this tutorial you'll be able to perform many common Drupal environment and administration tasks from the command line with Drush. We're not going to cover all of the environment management commands in this tutorial, just some of the more popular ones. We encourage you to explore further on your own.
What Is Drush?
FreeDrush, aka The Drupal Shell, is a command line utility and UNIX scripting interface for Drupal. It allows access to common Drupal features and tasks via the command line. It can help speed up common tasks for Drupal site builders, developers, and DevOps teams. Among other things, it makes it easier to integrate Drupal into CI/CD workflows.
In this tutorial we'll:
- Learn what Drush is and what can be done with Drush
- Install Drush
- Find a list of Drush commands
- Learn how to execute commands
By the end of this tutorial, you'll understand how to install and use Drush with your Drupal projects, navigate the list of its commands and run them. This is intended as an overview. Other tutorials will provide more detail about common commands and use-cases.
Make your custom Drush command more flexible by allowing users to pass command line arguments into it. For example, rather than hard-coding that the command lists users with a specific status, allow the desired status to be specified at run-time. This allows the command's logic to be more generic, and to return different results, or operate on different data, based on the provided parameters.
Parameters are variables that are passed from user input at the command line into the Drush command method. Typically, they are either single string values, or comma-delimited strings of values. Parameters are typically used to provide input for the command related to what the command should work on, in contrast to options, which are typically used to configure how the command works.
In this tutorial we'll:
- Declare parameters for a custom Drush command in its attributes
- Use the parameter input inside the custom Drush command method
By the end of this tutorial you should understand how to work with parameters inside custom Drush commands.
When you create a custom Drush command it might be useful to allow users to pass options (predefined values) that change the way a command works. You can think of options as being flags, or variables, that affect the command's internal logic. As an example, consider the Drush core user:login
command which by default returns a one-time login link for the root account. The command also accepts an optional --name
option which allows the internal logic to create a link for a specified user instead of only being able to create links for the root user. This makes the command useful in a wider variety of situations. Another common option is the --format
option which allows a user to specify that they want the command to return its output in a format (CSV, JSON, Table, etc.) other than the default.
Options are defined in the Drush command's attributes. Their values are passed as part of an associative array to the command method. Unlike parameters, options are not ordered, so you can specify them in any order, and they are called with two dashes like --my-option
. Options are always optional, not required, and can be set up to accept a value --name=John
or as a boolean flag without a value --translate
.
In this tutorial we'll:
- Declare options for a custom Drush command in its attributes
- Learn how to use these options inside the custom Drush command method
By the end of this tutorial, you should be able to add options to your own custom Drush commands.
Drush commands are commonly run in the Drupal docroot, the directory where Drupal's files live. This is a relatively simple task on your local development environment. But if you're working on multiple sites and each of those sites has one or more remote environments that you connect to via SSH, workflows quickly become complicated. Creating and using Drush site aliases allows you to run Drush commands on any site, local or remote, that you have credentials to access, from any location on your computer that has access to a Drush executable.
Imagine you've got a Drupal project with dev, test, and live environments in the cloud somewhere. And you need to clear the cache on the dev environment. You could SSH to that environment, and execute drush cr
there. Or, after configuring a site alias you could do something like:
drush @provider.dev cr -y
And Drush will connect to the remote environment and clear the cache.
Site aliases allow bundling the configuration options (--uri
, --root
, etc.) for a specific remote server under an alias. This reduces the amount of typing required. Even more importantly, it helps teams agree on a common definition for environments like @dev
, @test
, and @live
by committing their configurations to version control.
In this tutorial we'll:
- Define what a Drush site alias is
- Understand the use case for aliases
- Learn how to configure and use Drush site aliases
By the end of this tutorial, you should understand how Drush site aliases work, how to create Drush site aliases, and how to use them in a Drush command.
The Drush executable can be configured through the use of YAML configuration files and environment variables. This configuration can help cut down on typing lengthy frequently-used commands. You can tell Drush to look for command files in project-specific locations. Configuration can also set the value(s) of a specific command's options, instead of having to type them at the command line every time.
In this tutorial we'll:
- Explore different Drush configuration options
- Learn how to configure Drush for your project
By the end of this tutorial, you'll know how to provide project specific, and global, configuration that helps customize Drush and improve your own efficiency.
Creating a custom Drush command requires creating a PHP class that Drush can find with methods that have PHP attributes that provide metadata about each custom command. You'll use an autowire trait to inject any services into it. You'll also optionally modify the project's composer.json to tell Drush what versions of Drush the command is compatible with.
Custom Drush commands are a great way to expose your custom module's features to help automate these tasks and allow users to perform them as background processes. They can also provide a more efficient way to execute PHP code that takes a long time and is prone to timing out when run via the web server.
Depending on your use-case it can also be more efficient to create a custom Drush command to execute your logic instead of coding a complete UI. For example, if all the command needs to do is generate a CSV list it might take less effort to write a Drush command and pipe the output to a file than to create a UI that generates a file and prompts the user to download it.
In this tutorial we'll:
- Declare a new custom Drush command inside a custom module
- Make our custom Drush command output a list of all the blocked users on the site
- Verify our new command is working
By the end of this tutorial you should understand how to create a custom Drush command that returns a list of blocked users.