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.

In addition to using one of the existing generators, developers can write their own Drush generator commands. This can help speed up repetitive tasks and reduce the use of boilerplate code that is prone to human error.

Generators are provided through Drush's integration with the Drupal Code Generator project. Writing new generators isn't specific to Drush, though if you're creating generators for Drupal it is definitely easiest with Drush as a wrapper.

Similar to Drush commands, generators can be supplied by a Drupal module or declared globally. If you have a feature-specific functionality, it's best to ship your custom generator within the custom module. Otherwise, a global generator can be declared and used.

In this tutorial we'll:

• Explain the anatomy of a Drush generator
• Write a custom Drush generator for handling a site's development.services.yml file, and use it in a project

By the end of this tutorial you should understand how to create, or customize, a Drush code generator and use it in your project.

Code generators are great productivity boosters that allow generating scaffolds for common development tasks in Drupal. One of the most common use cases for generators is scaffolding the code required for a custom entity type. Custom entities require many files and complicated annotations in order to function properly. There is a lot of boilerplate code that is more-or-less the same for every entity type. Creating all the files is repetitive, time-consuming, and prone to human error. Generators can help automate this task and make creating your own custom entity types quicker.

In this tutorial we'll:

• Learn how to generate the code for a custom entity with Drush
• Learn about the options that generators provide for custom entities

By the end of this tutorial you should know how to generate custom entities with Drush.

The Drupal Entity API makes it easy to define new custom content entity types. And in most cases whenever you want to store custom content in Drupal you should use the Entity API instead of making CRUD queries directly to the database. This ensures your code is more consistent, and allows you to take advantage of all the features of the Entity API like access control, Views module integration, and automatic JSON:API support. As well as making it easier for others to extend your custom content by ensuring all the proper hooks and lifecycle events get invoked when new content items get created, updated, and deleted.

In this tutorial we'll:

• Walk through the process of creating a custom content entity

By the end of this lesson you'll be able to create your own custom content entity contained in a module.

One of Drupal's more powerful features is the fine-grained ability to control permissions and control access to content. The Entity API helps enable this functionality by providing an interface to help define access control.

In this tutorial we'll:

• Look at how access control is handled, using Drupal core as an example.
• Demonstrate how to implement access control in a custom module.
• Learn about the hooks that allow developers to modify access control for entities provided by another module.

By the end of this tutorial you should have a better understanding of the entity access control system and how to work with it.

Entities are the building blocks that make up just about everything on a Drupal site. Regardless of whether entities provide configuration information or content, they are absolutely crucial to Drupal's data model.

In this tutorial we'll:

• Look at the overall class hierarchy between the various entity types to see how they're related.
• Examine differences between configuration and content entities in the code that defines them.
• Look at some of the core code required to create an entity type.

By the end of this lesson you should be able to use an example to create a custom entity type in code.

Often when building a site in Drupal you'll find yourself wanting to display a list of nodes, or find entities created by a particular author, or locate some content based on a particular set of criteria. Rather than querying the database directly, Drupal provides a helper class, EntityQuery, to make things a bit easier. The EntityQuery class will probably look very familiar to you if you're familiar with the Database API, or the EntityFieldQuery class in Drupal 7.

In this tutorial we'll:

• Go through several examples of using EntityQuery to find subsets of content.
• Demonstrate how to iterate over the results of an EntityQuery query.

By the end of this tutorial, you should understand how to use entity queries to create custom sets of data from entities.

When learning Drupal development, it won't be long before you encounter the word "entity" and the Entity API. But what are entities in Drupal? How can you use them to build your site? When should you use the Entity API?

This tutorial will explain Drupal's Entity system from a high level. We'll look at:

• The main problems the Entity system solves
• Key terms you should know
• Key concepts we'll explore as we dive into Drupal's Entity API

By the end of this tutorial you should be able to explain the problems that the Entity API solves, and when you should use it in your own code.

Drupal includes the Symfony Validator component, and provides an Entity Validation API to assist in validating the values of fields on an entity. By using the Entity Validation API you can ensure that you're validation logic is applied to Entity CRUD operations regardless of how they are triggered. Whether editing an Entity via a Form API form, or creating a new Entity via the REST API, the same validation code will be used.

Using the Entity Validation API in order to validate the value of a field on an entity requires:

• Defining (or choosing) a constraint plugin
• Defining (or choosing) a validation plugin
• Adding the constraint to the field definition

In this tutorial, we'll look at how this Validation API works and how it can be used in custom code to ensure our entities have properly constructed values. We'll look at how this validation works in Drupal core and how we can add our own additional constraints. We'll also see how to work with the error messages returned from the validator when our entity doesn't pass validation.

Containers are sandboxed applications that can be run anywhere, no matter the underlying host OS. Docker containers are quite different from VMs in a number of ways that need to be understood before we can use them to develop Drupal sites.

In this tutorial, we'll:

• Define a container
• Explain how a container is a more limited environment than a VM

Media source plugins provide the link between media entities in Drupal and the actual media asset itself. They are the code that understand the difference between an image, a video, and a Tweet, and perform the translation that allows the media ecosystem to treat all media entities equally. For example, local image files, and remote YouTube videos, can both be catalogued in a similar way as media entities, but they need very different handling when it comes to displaying them.

Media sources are represented as plugins, there are a handful in Drupal core, and a developer can add new plugins to represent any type of media your application needs to catalogue.

In this tutorial we'll learn:

• How media source plugins relate to Media Types
• The responsibilities of a media source plugin

By the end of this tutorial you should be able to define the role of a media source plugin and understand what's required to define your own.

It's not uncommon to patch, or customize, contributed modules during the lifetime of a site. It's important to know if you've done so when planning for a migration since you'll want to be sure that you don't lose any customizations when you start using an updated version of a module.

In this tutorial we will walk through using the Hacked! module to check for any alterations to your Drupal code base.

The Drupal-to-Drupal migration system is still a work in progress. As such, there are a few things that simply don't work, and a few others that still have kinks to be ironed out. In this tutorial, we'll look at some of the common hang-ups that we've encountered, the status of resolving those issues, and what your options are in the meantime.

In Drupal, there are 3 modules in core related to migration that you'll want to know about. These modules can help you import data into Drupal from disparate sources, or upgrade from a previous version of Drupal.

In this tutorial we'll look at what each of these core migration modules do, and talk about when you'll need to use them.

Drupal core provides support for migrating data from Drupal 6 or 7. The templates provided in core migrate your data in a very specific way. They attempt to copy things verbatim whenever possible. However, you may wish to alter this for your migrations. In this tutorial we are going to explore the various ways that you can alter the existing Drupal-to-Drupal migrations to meet your needs.