Generated Content

Drupal.org module page: https://www.drupal.org/project/generated_content

User stories

As a site owner
I want to see generated content before I have content
So that I can see how my site looks

As a Drupal developer
I want to control what is put into generated content
So that I have control over what is being generated

As a Drupal developer
I want to have a list of pre-generated pages with URLs
So that I can use them for Visual Regression testing during site releases

Installation

composer require drupal/generated_content

How it works

1. The module provides callbacks system to generate content entities within a code of a custom module sitting in generated_content/{entity_type}/{entity_bundle}.inc.

2. The module provides a helper (singleton) class to generate random and static content. It also supports extending this class in your custom module to enhance with your site-specific generation helpers.

3. Generated content entities are tracked in the Repository so that they could be referenced from other generated entities (e.g., generated Articles using generated Tags).

4. Content can be generated from UI /admin/config/development/generated-content or through a Drush command drush generated-content:create-content {entity_type} {bundle}.

5. Content can also be generated on module install if GENERATED_CONTENT_CREATE environment variable is set to 1. Generation can be further filtered by specified types in GENERATED_CONTENT_ITEMS environment variable as a comma-separated list of {entity_type}-{bundle} values:

   # Generate all items in my_module module when it is enabled.
   GENERATED_CONTENT_CREATE=1 drush pm-enable my_module
   
   # Generate only selected items in my_module module when it is enabled.
   GENERATED_CONTENT_CREATE=1 GENERATED_CONTENT_ITEMS=media-image,taxonomy_term-tags,node-page drush pm-enable my_module
   

See test example module 1 and test example module 2 for extensive examples.

See generated_content.api.php for API of callbacks system.

Difference with Devel Generate

Devel Generate and Generated Content are two different tools for creating content in Drupal. Devel Generate is mainly used for generating random dummy content, users, and taxonomy terms for testing and development. It allows you to specify how many and what types of entities to create, but the content is random.

On the other hand, Generated Content is for creating specific sets of content based on predefined settings. It is useful for ensuring the same content is produced each time, which is helpful for tasks like Visual Regression testing where consistency is key. Unlike Devel Generate, which is more about quick, random content, Generated Content is about having control and reproducibility for structured content setups.

Generated Content does not provide any generators itself, but it allows you to create your own generators and provides a harness to run them.

Example to generate Tags

<?php

/**
 * @file
 * Create generated Tags terms.
 */

use Drupal\Core\Link;
use Drupal\generated_content\Helpers\GeneratedContentHelper;
use Drupal\taxonomy\Entity\Term;

/**
 * Implements hook_generated_content_create_ENTITY_TYPE_BUNDLE_weight().
 */
function generated_content_example2_generated_content_create_taxonomy_term_tags_weight() {
  return 12;
}

/**
 * Implements hook_generated_content_create_ENTITY_TYPE_BUNDLE_tracking().
 */
function generated_content_example2_generated_content_create_taxonomy_term_tags_tracking() {
  return TRUE;
}

/**
 * Implements hook_generated_content_create_ENTITY_TYPE_BUNDLE().
 */
function generated_content_example2_generated_content_create_taxonomy_term_tags() {
  // Total number of terms to create.
  $total_terms_count = 10;

  /** @var \Drupal\generated_content\Helpers\GeneratedContentHelper $helper */
  $helper = GeneratedContentHelper::getInstance();

  $terms = [];

  for ($i = 0; $i < $total_terms_count; $i++) {
    // Create a term instance.
    $term = Term::create([
      'vid' => 'tags',
      'name' => 'Generated term ' . ($i + 1),
    ]);

    // Save term instance.
    $term->save();

    // Track saved term instance to return.
    $terms[] = $term;

    // Log creation of this entity.
    $helper::log(
      'Created "%s" term "%s" [ID: %s] %s',
      $term->bundle(),
      $term->toLink()->toString(),
      $term->id(),
      Link::createFromRoute('Edit', 'entity.taxonomy_term.edit_form', ['taxonomy_term' => $term->id()])->toString()
    );
  }

  // Return created term instances.
  return $terms;
}

Generation helper

Generation helper class GeneratedContentHelper is a Singleton class which provides:

1. Random non-Drupal scalar values generation.
2. Static non-Drupal scalar values generation.
3. Random asset generator (files of different types).
4. Static asset generator (files from pre-defined assets).
5. Random Drupal entity values generation.
6. Static Drupal entity values generation.

Extending generation helper

See example of class extension: modules/generated_content_example2/src/GeneratedContentExample2Helper.php

See example of class usage: modules/generated_content_example2/generated_content/node/article.inc

Random vs Static content

Sometimes, it is sufficient to simply populate entities with random content to make the site look "not empty". Depending on your deployment strategy (if you are enabling content generation modules on every deployment on top of the fresh database), this may change the content on every deployment.

However, there are times when all generated content can still be a "placeholder" content, but it should be "static" between deployments, so that all content and it's aliases would not change. This is specifically important for Visual Regression testing during a release: the tool can compare generated pages with known aliases in 2 environments and report differences, if any.

Roadmap

1. Add more random and static generators.
2. Add tests for existing random and static generators.
3. Suggest yours.

Local development

Provided that you have PHP installed locally, you can develop an extension using the provided scripts.

Build

Run .devtools/build.sh (or ahoy build if Ahoy is installed) to start inbuilt PHP server locally and run the same commands as in CI, plus installing a site and your extension automatically.

Code linting

Run tools individually (or ahoy lint to run all tools if Ahoy is installed) to lint your code according to the Drupal coding standards.

cd build

vendor/bin/phpcs
vendor/bin/phpstan
vendor/bin/rector --clear-cache --dry-run
vendor/bin/phpmd . text phpmd.xml
vendor/bin/twig-cs-fixer

• PHPCS config: phpcs.xml
• PHPStan config: phpstan.neon
• PHPMD config: phpmd.xml
• Rector config: rector.php
• Twig CS Fixer config: .twig-cs-fixer.php
• Patches can be applied to the dependencies: add a patch to the patches section of composer.json. Local patches will be sourced from the patches directory.

Tests

Run tests individually with cd build && ./vendor/bin/phpunit (or ahoy test if Ahoy is installed) to run all test for your extension.

Browsing SQLite database

To browse the contents of created SQLite database (located at /tmp/site_[EXTENSION_NAME].sqlite), use DB Browser for SQLite.