Upgrading an Extension Module

This page provides useful short snippets of code to help module developers upgrade their Tripal v3 compatible modules to work with Drupal 10. This list is not comprehensive or complete, but is meant to be an aid.

tripal_set_message() and tripal_report_error()

These functions have been upgraded and thus can be used as is. However, the new way is to use a logger service. For example:

$logger = \Drupal::service('tripal.logger');
$logger->notice('Hello world');
$logger->error('Hello world');

For more detailed information see the Tripal Logger documentation.

drupal_set_message()

Changelog: https://www.drupal.org/node/2774931

use Drupal\Core\Messenger\MessengerInterface;
// if not set by constructor...
$this->messenger = \Drupal::messenger();

// Add specific type of message within classes.
$this->messenger->addMessage('Hello world', 'custom');
$this->messenger->addStatus('Hello world');
$this->messenger->addWarning('Hello world');
$this->messenger->addError('Hello world');

// In procedural code:
$messenger = \Drupal::messenger();
$messenger->addMessage('Hello world', 'custom');
$messenger->addStatus('Hello world');
$messenger->addWarning('Hello world');
$messenger->addError('Hello world');

format_date()

\Drupal::service('date.formatter')->format($time);

Loading a User Object

To load a user using a known user ID.

// Load a user with a known UID in the $uid variable.
$user = \Drupal\user\Entity\User::load($uid);

To get the current user:

$current_user = \Drupal::currentUser();
$user = \Drupal\user\Entity\User::load($current_user->id());

Creating Links

To create HTML links the Drupal 7 was was:

$link = l('Administration', '/admin')

The Drupal 10 approach is:

use Drupal\Core\Link;
use Drupal\Core\Url;

$link = Link::fromTextAndUrl('Administration', Url::fromUri('internal:/admin'))

Using Links in drupal_set_message:

$jobs_url = Link::fromTextAndUrl('jobs page',
  Url::fromUri('internal:/admin/tripal/tripal_jobs'))->toString();
drupal_set_message(t("Check the @jobs_url for status.",
  ['@jobs_url' => $jobs_url]));

Database Queries

db_query

The db_query function is deprecated in Drupal 9. To perform a database query you will need to rework any calls to the db_query function in the following way:

// Get the database object.
$database = \Drupal::database();

// Perform the query by passing the SQL statement and arguments.
$query = $database->query($sql, $args);

// Get the result(s).
$job = $query->fetchObject();

drupal_write_record

The drupal_write_record was useful in Drupal 7 for directly working with tables that Drupal was aware of. Here’s the replacement:

$database = \Drupal::database();
$num_updated = $database->update('tripal_jobs')
  ->fields([
    'status' => 'Cancelled',
    'progress' => 0,
  ])
  ->condition('job_id', $this->job->job_id)
  ->execute();

Views

The hook_views_data() function

The hook_views_data function is used to expose tables within Drupal to the Drupal Views. The function returns an array that defines how tables can be handled by Views. Fortunately, this is mostly backwards compatible and you can keep the function as is. However, you will need to make the following changes:

1. Where handlers are defined for the field, filter, sort, relationship, argument you must change the key handler to id.

2. Handler names are now just a single word. The following table provides some common name changes.

Handler Type	D7 Handler Function	D8/9 Handler ID
field	views_handler_field	standard (strings)
	views_handler_field_numeric	numeric
	views_handler_field_date	date
filter	views_handler_filter_numeric	numeric
	views_handler_filter_string	string
	views_handler_filter_date	date
sort	views_handler_sort	standard (strings)
	views_handler_sort_date	date
argument	views_handler_argument_string	string
	views_handler_argument_date	date
relationship	views_handler_relationship	standard

You can find additional handlers at these API pages:

• Fields

• Filters

• Sort

• Arguments

• Relationships

The hook_views_default_views() function

In Drupal v7 this function was used to provide the set of views that you would like the end-user to see automatically when the module is installed. This function is no longer used neither is the <modulename>.views_default.inc file where this hook would be stored. Instead the default views are provided in YML format.

Step 1: Create the View: To recreate any views that your module provided in Drupal 7, you must recreate the View using the Views UI interface. No coding is required.

Step 2: Export the View: Once the view has been recreated, you can export the YML for the view by navigating to Admin >> Configuration >> Configuration Synchronization. Click the Export tab at the top, then click the single item link below the tab. In the page that appears you should then select View from the Configuration type dropdown and then select the name of the view you want to export. The YML code for the selected view will appear in the textarea below. The screenshot below shows an example:

Step 3: Create the View YML file: Once you have the YML code for the view, you must create a new file named views.view.<view_name>.yml and place the code inside of it. Where <view_name> is the machine name of the view. You can safely remove the first uuid line. This file must be placed in the config/install directory of your module.

Step 4: Reinstall the Module: In order for Drupal Views to see this new view you must reinstall the module.

Embed a View on a Page

In Drupal v7 you could embed a view onto any page by using code similar to the following

$view = views_embed_view('tripal_admin_jobs', 'default');

In Drupal 8 use code similar to the following to embed a view on a page:

$view = \Drupal\views\Views::getView('tripal_jobs');
$view->setDisplay('default');
if ($view->access('default')) {
  return $view->render();
}
else {
  return [
    '#markup' => 'You do not have access to view this page.',
  ];
}

Attaching CSS

In Drupal 10 CSS files are part of “libraries”. Libraries are groups of “assets” such as CSS, JS, or other resources needed for a particular set of pages that the module provides. Libraries are defined in the <module_name>.libraries.yml file. For information about preparing your CSS files with drupal see the page about adding css and js files to a module. Once the CSS is setup correctly, you want to add “libraries” to pages that use them. This is done by adding an ‘#attached’ element to the render array returned by a page using the following form:

'#attached' => [
  'library' => ['<module_name>/<library_name>'],
]

Replace <module_name> and <library_name> with appropriate values.