class QueueExampleForm
Same name in other branches
- 3.x modules/queue_example/src/Form/QueueExampleForm.php \Drupal\queue_example\Form\QueueExampleForm
- 4.0.x modules/queue_example/src/Form/QueueExampleForm.php \Drupal\queue_example\Form\QueueExampleForm
Form with examples on how to use queue.
Hierarchy
- class \Drupal\queue_example\Forms\QueueExampleForm extends \Drupal\Core\Form\FormBase
Expanded class hierarchy of QueueExampleForm
1 string reference to 'QueueExampleForm'
- queue_example.routing.yml in queue_example/
queue_example.routing.yml - queue_example/queue_example.routing.yml
File
-
queue_example/
src/ Forms/ QueueExampleForm.php, line 19
Namespace
Drupal\queue_example\FormsView source
class QueueExampleForm extends FormBase {
/**
* The queue object.
*
* @var \Drupal\Core\Queue\QueueFactory
*/
protected $queueFactory;
/**
* The database object.
*
* @var \Drupal\Core\Database\Connection
*/
protected $database;
/**
* The CronInterface object.
*
* @var \Drupal\Core\CronInterface
*/
protected $cron;
/**
* What kind of queue backend are we using?
*
* @var string
*/
protected $queueType;
/**
* Constructor.
*
* @param \Drupal\Core\Queue\QueueFactory $queue_factory
* Queue factory service to get new/existing queues for use.
* @param \Drupal\Core\Database\Connection $database
* The database connection to be used.
* @param Drupal\Core\CronInterface $cron
* The cron service.
* @param Drupal\Core\Site\Settings $settings
* The site settings.
*/
public function __construct(QueueFactory $queue_factory, Connection $database, CronInterface $cron, Settings $settings) {
$this->queueFactory = $queue_factory;
$this->queueType = $settings->get('queue_default', 'queue.database');
$this->database = $database;
$this->cron = $cron;
}
/**
* {@inheritdoc}
*/
public static function create(ContainerInterface $container) {
$form = new static($container->get('queue'), $container->get('database'), $container->get('cron'), $container->get('settings'));
$form->setMessenger($container->get('messenger'));
return $form;
}
/**
* {@inheritdoc}
*/
public function getFormId() {
// Return a string that is the unique ID of our form. Best practice here is
// to namespace the form based on your module's name.
return 'queue_example';
}
/**
* {@inheritdoc}
*/
public function buildForm(array $form, FormStateInterface $form_state) {
// Simple counter that makes it possible to put auto-incrementing default
// string into the string to insert.
if (empty($form_state->get('insert_counter'))) {
$form_state->set('insert_counter', 1);
}
$queue_name = $form_state->getValue('queue_name') ?: 'queue_example_first_queue';
$items = $this->retrieveQueue($queue_name);
$form['help'] = [
'#type' => 'markup',
'#markup' => '<div>' . $this->t('This page is an interface on the Drupal queue API. You can add new items to the queue, "claim" one (retrieve the next item and keep a lock on it), and delete one (remove it from the queue). Note that claims are not expired until cron runs, so there is a special button to run cron to perform any necessary expirations.') . '</div>',
];
$form['wrong_queue_warning'] = [
'#type' => 'markup',
'#markup' => '<div>' . $this->t('Note: the example works only with the default queue implementation, which is not currently configured!!') . '</div>',
'#access' => !$this->doesQueueUseDB(),
];
$queue_names = [
'queue_example_first_queue',
'queue_example_second_queue',
];
$form['queue_name'] = [
'#type' => 'select',
'#title' => $this->t('Choose queue to examine'),
'#options' => array_combine($queue_names, $queue_names),
'#default_value' => $queue_name,
];
$form['queue_show'] = [
'#type' => 'submit',
'#value' => $this->t('Show queue'),
'#submit' => [
'::submitShowQueue',
],
];
$form['status_fieldset'] = [
'#type' => 'fieldset',
'#title' => $this->t('Queue status for @name', [
'@name' => $queue_name,
]),
'#collapsible' => TRUE,
];
if (count($items) > 0) {
$form['status_fieldset']['status'] = [
'#theme' => 'table',
'#header' => [
$this->t('Item ID'),
$this->t('Claimed/Expiration'),
$this->t('Created'),
$this->t('Content/Data'),
],
'#rows' => array_map([
$this,
'processQueueItemForTable',
], $items),
];
}
else {
$form['status_fieldset']['status'] = [
'#type' => 'markup',
'#markup' => $this->t('There are no items in the queue.'),
];
}
$form['insert_fieldset'] = [
'#type' => 'fieldset',
'#title' => $this->t('Insert into @name', [
'@name' => $queue_name,
]),
];
$form['insert_fieldset']['string_to_add'] = [
'#type' => 'textfield',
'#size' => 10,
'#default_value' => $this->t('item @counter', [
'@counter' => $form_state->get('insert_counter'),
]),
];
$form['insert_fieldset']['add_item'] = [
'#type' => 'submit',
'#value' => $this->t('Insert into queue'),
'#submit' => [
'::submitAddQueueItem',
],
];
$form['claim_fieldset'] = [
'#type' => 'fieldset',
'#title' => $this->t('Claim from queue'),
'#collapsible' => TRUE,
];
$form['claim_fieldset']['claim_time'] = [
'#type' => 'radios',
'#title' => $this->t('Claim time, in seconds'),
'#options' => [
0 => $this->t('none'),
5 => $this->t('5 seconds'),
60 => $this->t('60 seconds'),
],
'#description' => $this->t('This time is only valid if cron runs during this time period. You can run cron manually below.'),
'#default_value' => $form_state->getValue('claim_time') ?: 5,
];
$form['claim_fieldset']['claim_item'] = [
'#type' => 'submit',
'#value' => $this->t('Claim the next item from the queue'),
'#submit' => [
'::submitClaimItem',
],
];
$form['claim_fieldset']['claim_and_delete_item'] = [
'#type' => 'submit',
'#value' => $this->t('Claim the next item and delete it'),
'#submit' => [
'::submitClaimDeleteItem',
],
];
$form['claim_fieldset']['run_cron'] = [
'#type' => 'submit',
'#value' => $this->t('Run cron manually to expire claims'),
'#submit' => [
'::submitRunCron',
],
];
$form['delete_queue'] = [
'#type' => 'submit',
'#value' => $this->t('Delete the queue and items in it'),
'#submit' => [
'::submitDeleteQueue',
],
];
return $form;
}
/**
* {@inheritdoc}
*/
public function submitForm(array &$form, FormStateInterface $form_state) {
}
/**
* Retrieves the queue from the database for display purposes only.
*
* It is not recommended to access the database directly, and this is only
* here so that the user interface can give a good idea of what's going on
* in the queue.
*
* @param string $queue_name
* The name of the queue from which to fetch items.
*
* @return array
* An array of item arrays.
*/
public function retrieveQueue($queue_name) {
$items = [];
// This example requires the default queue implementation to work,
// so we bail if some other queue implementation has been installed.
if (!$this->doesQueueUseDb()) {
return $items;
}
// Make sure there are queue items available. The queue will not create our
// database table if there are no items.
if ($this->queueFactory
->get($queue_name)
->numberOfItems() >= 1) {
$result = $this->database
->query('SELECT item_id, data, expire, created FROM {' . DatabaseQueue::TABLE_NAME . '} WHERE name = :name ORDER BY item_id', [
':name' => $queue_name,
], [
'fetch' => \PDO::FETCH_ASSOC,
]);
foreach ($result as $item) {
$items[] = $item;
}
}
return $items;
}
/**
* Check if we are using the default database queue.
*
* @return bool
* TRUE if we are using the default database queue implementation.
*/
protected function doesQueueUseDb() {
return $this->queueType == 'queue.database';
}
/**
* Submit function for the show-queue button.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitShowQueue(array &$form, FormStateInterface $form_state) {
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
// There is no harm in trying to recreate existing.
$queue->createQueue();
// Get the number of items.
$count = $queue->numberOfItems();
// Update the form item counter.
$form_state->set('insert_counter', $count + 1);
// Unset the string_to_add textbox.
$form_state->unsetValue('string_to_add');
$form_state->setRebuild();
}
/**
* Submit function for the insert-into-queue button.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitAddQueueItem(array &$form, FormStateInterface $form_state) {
// Get a queue (of the default type) called 'queue_example_queue'.
// If the default queue class is SystemQueue this creates a queue that
// stores its items in the database.
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
// There is no harm in trying to recreate existing.
$queue->createQueue();
// Queue the string.
$queue->createItem($form_state->getValue('string_to_add'));
$count = $queue->numberOfItems();
$this->messenger()
->addMessage($this->t('Queued your string (@string_to_add). There are now @count items in the queue.', [
'@count' => $count,
'@string_to_add' => $form_state->getValue('string_to_add'),
]));
// Allows us to keep information in $form_state.
$form_state->setRebuild();
// Unsetting the string_to_add allows us to set the incremented default
// value for the user so they don't have to type anything.
$form_state->unsetValue('string_to_add');
$form_state->set('insert_counter', $count + 1);
}
/**
* Submit function for the "claim" button.
*
* Claims (retrieves) an item from the queue and reports the results.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitClaimItem(array &$form, FormStateInterface $form_state) {
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
// There is no harm in trying to recreate existing.
$queue->createQueue();
$item = $queue->claimItem($form_state->getValue('claim_time'));
$count = $queue->numberOfItems();
if (!empty($item)) {
$this->messenger()
->addMessage($this->t('Claimed item id=@item_id string=@string for @seconds seconds. There are @count items in the queue.', [
'@count' => $count,
'@item_id' => $item->item_id,
'@string' => $item->data,
'@seconds' => $form_state->getValue('claim_time'),
]));
}
else {
$this->messenger()
->addMessage($this->t('There were no items in the queue available to claim. There are @count items in the queue.', [
'@count' => $count,
]));
}
$form_state->setRebuild();
}
/**
* Submit function for "Claim and delete" button.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitClaimDeleteItem(array &$form, FormStateInterface $form_state) {
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
// There is no harm in trying to recreate existing.
$queue->createQueue();
$count = $queue->numberOfItems();
$item = $queue->claimItem(60);
if (!empty($item)) {
$this->messenger()
->addMessage($this->t('Claimed and deleted item id=@item_id string=@string for @seconds seconds. There are @count items in the queue.', [
'@count' => $count,
'@item_id' => $item->item_id,
'@string' => $item->data,
'@seconds' => $form_state->getValue('claim_time'),
]));
$queue->deleteItem($item);
$count = $queue->numberOfItems();
$this->messenger()
->addMessage($this->t('There are now @count items in the queue.', [
'@count' => $count,
]));
}
else {
$count = $queue->numberOfItems();
$this->messenger()
->addMessage($this->t('There were no items in the queue available to claim/delete. There are currently @count items in the queue.', [
'@count' => $count,
]));
}
$form_state->setRebuild();
}
/**
* Submit function for "run cron" button.
*
* Runs cron (to release expired claims) and reports the results.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitRunCron(array &$form, FormStateInterface $form_state) {
$this->cron
->run();
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
// @see https://www.drupal.org/node/2705809
if ($queue instanceof QueueGarbageCollectionInterface) {
$queue->garbageCollection();
}
// There is no harm in trying to recreate existing.
$queue->createQueue();
$count = $queue->numberOfItems();
$this->messenger()
->addMessage($this->t('Ran cron. If claimed items expired, they should be expired now. There are now @count items in the queue', [
'@count' => $count,
]));
$form_state->setRebuild();
}
/**
* Submit handler for clearing/deleting the queue.
*
* @param array $form
* Form definition array.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* Form state object.
*/
public function submitDeleteQueue(array &$form, FormStateInterface $form_state) {
$queue = $this->queueFactory
->get($form_state->getValue('queue_name'));
$queue->deleteQueue();
$this->messenger()
->addMessage($this->t('Deleted the @queue_name queue and all items in it', [
'@queue_name' => $form_state->getValue('queue_name'),
]));
}
/**
* Helper method to format a queue item for display in a summary table.
*
* @param array $item
* Queue item array with keys for item_id, expire, created, and data.
*
* @return array
* An array with the queue properties in the right order for display in a
* summary table.
*/
private function processQueueItemForTable(array $item) {
if ($item['expire'] > 0) {
$item['expire'] = $this->t('Claimed: expires %expire', [
'%expire' => date('r', $item['expire']),
]);
}
else {
$item['expire'] = $this->t('Unclaimed');
}
$item['created'] = date('r', $item['created']);
$item['content'] = Html::escape(unserialize($item['data']));
unset($item['data']);
return $item;
}
}
Members
Title Sort descending | Modifiers | Object type | Summary |
---|---|---|---|
QueueExampleForm::$cron | protected | property | The CronInterface object. |
QueueExampleForm::$database | protected | property | The database object. |
QueueExampleForm::$queueFactory | protected | property | The queue object. |
QueueExampleForm::$queueType | protected | property | What kind of queue backend are we using? |
QueueExampleForm::buildForm | public | function | |
QueueExampleForm::create | public static | function | |
QueueExampleForm::doesQueueUseDb | protected | function | Check if we are using the default database queue. |
QueueExampleForm::getFormId | public | function | |
QueueExampleForm::processQueueItemForTable | private | function | Helper method to format a queue item for display in a summary table. |
QueueExampleForm::retrieveQueue | public | function | Retrieves the queue from the database for display purposes only. |
QueueExampleForm::submitAddQueueItem | public | function | Submit function for the insert-into-queue button. |
QueueExampleForm::submitClaimDeleteItem | public | function | Submit function for "Claim and delete" button. |
QueueExampleForm::submitClaimItem | public | function | Submit function for the "claim" button. |
QueueExampleForm::submitDeleteQueue | public | function | Submit handler for clearing/deleting the queue. |
QueueExampleForm::submitForm | public | function | |
QueueExampleForm::submitRunCron | public | function | Submit function for "run cron" button. |
QueueExampleForm::submitShowQueue | public | function | Submit function for the show-queue button. |
QueueExampleForm::__construct | public | function | Constructor. |