5 * Functions for form and batch generation and processing.
8 use Drupal\Component\Utility\UrlHelper;
9 use Drupal\Core\Render\Element;
10 use Drupal\Core\Render\Element\RenderElement;
11 use Drupal\Core\Template\Attribute;
13 use Symfony\Component\HttpFoundation\RedirectResponse;
16 * Prepares variables for select element templates.
18 * Default template: select.html.twig.
20 * It is possible to group options together; to do this, change the format of
21 * $options to an associative array in which the keys are group labels, and the
22 * values are associative arrays in the normal $options format.
25 * An associative array containing:
26 * - element: An associative array containing the properties of the element.
27 * Properties used: #title, #value, #options, #description, #extra,
28 * #multiple, #required, #name, #attributes, #size.
30 function template_preprocess_select(&$variables) {
31 $element = $variables['element'];
32 Element::setAttributes($element, ['id', 'name', 'size']);
33 RenderElement::setAttributes($element, ['form-select']);
35 $variables['attributes'] = $element['#attributes'];
36 $variables['options'] = form_select_options($element);
40 * Converts an options form element into a structured array for output.
42 * This function calls itself recursively to obtain the values for each optgroup
43 * within the list of options and when the function encounters an object with
44 * an 'options' property inside $element['#options'].
46 * @param array $element
47 * An associative array containing the following key-value pairs:
48 * - #multiple: Optional Boolean indicating if the user may select more than
50 * - #options: An associative array of options to render as HTML. Each array
51 * value can be a string, an array, or an object with an 'option' property:
52 * - A string or integer key whose value is a translated string is
53 * interpreted as a single HTML option element. Do not use placeholders
54 * that sanitize data: doing so will lead to double-escaping. Note that
55 * the key will be visible in the HTML and could be modified by malicious
56 * users, so don't put sensitive information in it.
57 * - A translated string key whose value is an array indicates a group of
58 * options. The translated string is used as the label attribute for the
59 * optgroup. Do not use placeholders to sanitize data: doing so will lead
60 * to double-escaping. The array should contain the options you wish to
61 * group and should follow the syntax of $element['#options'].
62 * - If the function encounters a string or integer key whose value is an
63 * object with an 'option' property, the key is ignored, the contents of
64 * the option property are interpreted as $element['#options'], and the
65 * resulting HTML is added to the output.
66 * - #value: Optional integer, string, or array representing which option(s)
67 * to pre-select when the list is first displayed. The integer or string
68 * must match the key of an option in the '#options' list. If '#multiple' is
69 * TRUE, this can be an array of integers or strings.
70 * @param array|null $choices
71 * (optional) Either an associative array of options in the same format as
72 * $element['#options'] above, or NULL. This parameter is only used internally
73 * and is not intended to be passed in to the initial function call.
76 * A structured, possibly nested, array of options and optgroups for use in a
77 * select form element.
78 * - label: A translated string whose value is the text of a single HTML
79 * option element, or the label attribute for an optgroup.
80 * - options: Optional, array of options for an optgroup.
81 * - selected: A boolean that indicates whether the option is selected when
83 * - type: A string that defines the element type. The value can be 'option'
85 * - value: A string that contains the value attribute for the option.
87 function form_select_options($element, $choices = NULL) {
88 if (!isset($choices)) {
89 if (empty($element['#options'])) {
92 $choices = $element['#options'];
94 // array_key_exists() accommodates the rare event where $element['#value'] is NULL.
95 // isset() fails in this situation.
96 $value_valid = isset($element['#value']) || array_key_exists('#value', $element);
97 $value_is_array = $value_valid && is_array($element['#value']);
98 // Check if the element is multiple select and no value has been selected.
99 $empty_value = (empty($element['#value']) && !empty($element['#multiple']));
101 foreach ($choices as $key => $choice) {
102 if (is_array($choice)) {
104 'type' => 'optgroup',
106 'options' => form_select_options($element, $choice),
109 elseif (is_object($choice) && isset($choice->option)) {
110 $options = array_merge($options, form_select_options($element, $choice->option));
114 $key = (string) $key;
115 $empty_choice = $empty_value && $key == '_none';
116 if ($value_valid && ((!$value_is_array && (string) $element['#value'] === $key || ($value_is_array && in_array($key, $element['#value']))) || $empty_choice)) {
117 $option['selected'] = TRUE;
120 $option['selected'] = FALSE;
122 $option['type'] = 'option';
123 $option['value'] = $key;
124 $option['label'] = $choice;
125 $options[] = $option;
132 * Returns the indexes of a select element's options matching a given key.
134 * This function is useful if you need to modify the options that are
135 * already in a form element; for example, to remove choices which are
136 * not valid because of additional filters imposed by another module.
137 * One example might be altering the choices in a taxonomy selector.
138 * To correctly handle the case of a multiple hierarchy taxonomy,
139 * #options arrays can now hold an array of objects, instead of a
140 * direct mapping of keys to labels, so that multiple choices in the
141 * selector can have the same key (and label). This makes it difficult
142 * to manipulate directly, which is why this helper function exists.
144 * This function does not support optgroups (when the elements of the
145 * #options array are themselves arrays), and will return FALSE if
146 * arrays are found. The caller must either flatten/restore or
147 * manually do their manipulations in this case, since returning the
148 * index is not sufficient, and supporting this would make the
149 * "helper" too complicated and cumbersome to be of any help.
151 * As usual with functions that can return array() or FALSE, do not
152 * forget to use === and !== if needed.
155 * The select element to search.
157 * The key to look for.
160 * An array of indexes that match the given $key. Array will be
161 * empty if no elements were found. FALSE if optgroups were found.
163 function form_get_options($element, $key) {
165 foreach ($element['#options'] as $index => $choice) {
166 if (is_array($choice)) {
169 elseif (is_object($choice)) {
170 if (isset($choice->option[$key])) {
174 elseif ($index == $key) {
182 * Prepares variables for fieldset element templates.
184 * Default template: fieldset.html.twig.
186 * @param array $variables
187 * An associative array containing:
188 * - element: An associative array containing the properties of the element.
189 * Properties used: #attributes, #children, #description, #id, #title,
192 function template_preprocess_fieldset(&$variables) {
193 $element = $variables['element'];
194 Element::setAttributes($element, ['id']);
195 RenderElement::setAttributes($element);
196 $variables['attributes'] = isset($element['#attributes']) ? $element['#attributes'] : [];
197 $variables['prefix'] = isset($element['#field_prefix']) ? $element['#field_prefix'] : NULL;
198 $variables['suffix'] = isset($element['#field_suffix']) ? $element['#field_suffix'] : NULL;
199 $variables['title_display'] = isset($element['#title_display']) ? $element['#title_display'] : NULL;
200 $variables['children'] = $element['#children'];
201 $variables['required'] = !empty($element['#required']) ? $element['#required'] : NULL;
203 if (isset($element['#title']) && $element['#title'] !== '') {
204 $variables['legend']['title'] = ['#markup' => $element['#title']];
207 $variables['legend']['attributes'] = new Attribute();
208 // Add 'visually-hidden' class to legend span.
209 if ($variables['title_display'] == 'invisible') {
210 $variables['legend_span']['attributes'] = new Attribute(['class' => ['visually-hidden']]);
213 $variables['legend_span']['attributes'] = new Attribute();
216 if (!empty($element['#description'])) {
217 $description_id = $element['#attributes']['id'] . '--description';
218 $description_attributes['id'] = $description_id;
219 $variables['description']['attributes'] = new Attribute($description_attributes);
220 $variables['description']['content'] = $element['#description'];
222 // Add the description's id to the fieldset aria attributes.
223 $variables['attributes']['aria-describedby'] = $description_id;
226 // Suppress error messages.
227 $variables['errors'] = NULL;
231 * Prepares variables for details element templates.
233 * Default template: details.html.twig.
235 * @param array $variables
236 * An associative array containing:
237 * - element: An associative array containing the properties of the element.
238 * Properties used: #attributes, #children, #description, #required,
239 * #summary_attributes, #title, #value.
241 function template_preprocess_details(&$variables) {
242 $element = $variables['element'];
243 $variables['attributes'] = $element['#attributes'];
244 $variables['summary_attributes'] = new Attribute($element['#summary_attributes']);
245 if (!empty($element['#title'])) {
246 $variables['summary_attributes']['role'] = 'button';
247 if (!empty($element['#attributes']['id'])) {
248 $variables['summary_attributes']['aria-controls'] = $element['#attributes']['id'];
250 $variables['summary_attributes']['aria-expanded'] = !empty($element['#attributes']['open']) ? 'true' : 'false';
251 $variables['summary_attributes']['aria-pressed'] = $variables['summary_attributes']['aria-expanded'];
253 $variables['title'] = (!empty($element['#title'])) ? $element['#title'] : '';
254 // If the element title is a string, wrap it a render array so that markup
255 // will not be escaped (but XSS-filtered).
256 if (is_string($variables['title']) && $variables['title'] !== '') {
257 $variables['title'] = ['#markup' => $variables['title']];
259 $variables['description'] = (!empty($element['#description'])) ? $element['#description'] : '';
260 $variables['children'] = (isset($element['#children'])) ? $element['#children'] : '';
261 $variables['value'] = (isset($element['#value'])) ? $element['#value'] : '';
262 $variables['required'] = !empty($element['#required']) ? $element['#required'] : NULL;
264 // Suppress error messages.
265 $variables['errors'] = NULL;
269 * Prepares variables for radios templates.
271 * Default template: radios.html.twig.
273 * @param array $variables
274 * An associative array containing:
275 * - element: An associative array containing the properties of the element.
276 * Properties used: #title, #value, #options, #description, #required,
277 * #attributes, #children.
279 function template_preprocess_radios(&$variables) {
280 $element = $variables['element'];
281 $variables['attributes'] = [];
282 if (isset($element['#id'])) {
283 $variables['attributes']['id'] = $element['#id'];
285 if (isset($element['#attributes']['title'])) {
286 $variables['attributes']['title'] = $element['#attributes']['title'];
288 $variables['children'] = $element['#children'];
292 * Prepares variables for checkboxes templates.
294 * Default template: checkboxes.html.twig.
296 * @param array $variables
297 * An associative array containing:
298 * - element: An associative array containing the properties of the element.
299 * Properties used: #children, #attributes.
301 function template_preprocess_checkboxes(&$variables) {
302 $element = $variables['element'];
303 $variables['attributes'] = [];
304 if (isset($element['#id'])) {
305 $variables['attributes']['id'] = $element['#id'];
307 if (isset($element['#attributes']['title'])) {
308 $variables['attributes']['title'] = $element['#attributes']['title'];
310 $variables['children'] = $element['#children'];
314 * Prepares variables for vertical tabs templates.
316 * Default template: vertical-tabs.html.twig.
318 * @param array $variables
319 * An associative array containing:
320 * - element: An associative array containing the properties and children of
321 * the details element. Properties used: #children.
323 function template_preprocess_vertical_tabs(&$variables) {
324 $element = $variables['element'];
325 $variables['children'] = (!empty($element['#children'])) ? $element['#children'] : '';
329 * Prepares variables for input templates.
331 * Default template: input.html.twig.
333 * @param array $variables
334 * An associative array containing:
335 * - element: An associative array containing the properties of the element.
336 * Properties used: #attributes.
338 function template_preprocess_input(&$variables) {
339 $element = $variables['element'];
340 // Remove name attribute if empty, for W3C compliance.
341 if (isset($variables['attributes']['name']) && empty((string) $variables['attributes']['name'])) {
342 unset($variables['attributes']['name']);
344 $variables['children'] = $element['#children'];
348 * Prepares variables for form templates.
350 * Default template: form.html.twig.
353 * An associative array containing:
354 * - element: An associative array containing the properties of the element.
355 * Properties used: #action, #method, #attributes, #children
357 function template_preprocess_form(&$variables) {
358 $element = $variables['element'];
359 if (isset($element['#action'])) {
360 $element['#attributes']['action'] = UrlHelper::stripDangerousProtocols($element['#action']);
362 Element::setAttributes($element, ['method', 'id']);
363 if (empty($element['#attributes']['accept-charset'])) {
364 $element['#attributes']['accept-charset'] = "UTF-8";
366 $variables['attributes'] = $element['#attributes'];
367 $variables['children'] = $element['#children'];
371 * Prepares variables for textarea templates.
373 * Default template: textarea.html.twig.
375 * @param array $variables
376 * An associative array containing:
377 * - element: An associative array containing the properties of the element.
378 * Properties used: #title, #value, #description, #rows, #cols, #maxlength,
379 * #placeholder, #required, #attributes, #resizable.
381 function template_preprocess_textarea(&$variables) {
382 $element = $variables['element'];
383 $attributes = ['id', 'name', 'rows', 'cols', 'maxlength', 'placeholder'];
384 Element::setAttributes($element, $attributes);
385 RenderElement::setAttributes($element, ['form-textarea']);
386 $variables['wrapper_attributes'] = new Attribute();
387 $variables['attributes'] = new Attribute($element['#attributes']);
388 $variables['value'] = $element['#value'];
389 $variables['resizable'] = !empty($element['#resizable']) ? $element['#resizable'] : NULL;
390 $variables['required'] = !empty($element['#required']) ? $element['#required'] : NULL;
394 * Returns HTML for a form element.
395 * Prepares variables for form element templates.
397 * Default template: form-element.html.twig.
399 * In addition to the element itself, the DIV contains a label for the element
400 * based on the optional #title_display property, and an optional #description.
402 * The optional #title_display property can have these values:
403 * - before: The label is output before the element. This is the default.
404 * The label includes the #title and the required marker, if #required.
405 * - after: The label is output after the element. For example, this is used
406 * for radio and checkbox #type elements. If the #title is empty but the field
407 * is #required, the label will contain only the required marker.
408 * - invisible: Labels are critical for screen readers to enable them to
409 * properly navigate through forms but can be visually distracting. This
410 * property hides the label for everyone except screen readers.
411 * - attribute: Set the title attribute on the element to create a tooltip
412 * but output no label element. This is supported only for checkboxes
414 * \Drupal\Core\Render\Element\CompositeFormElementTrait::preRenderCompositeFormElement().
415 * It is used where a visual label is not needed, such as a table of
416 * checkboxes where the row and column provide the context. The tooltip will
417 * include the title and required marker.
419 * If the #title property is not set, then the label and any required marker
420 * will not be output, regardless of the #title_display or #required values.
421 * This can be useful in cases such as the password_confirm element, which
422 * creates children elements that have their own labels and required markers,
423 * but the parent element should have neither. Use this carefully because a
424 * field without an associated label can cause accessibility challenges.
426 * @param array $variables
427 * An associative array containing:
428 * - element: An associative array containing the properties of the element.
429 * Properties used: #title, #title_display, #description, #id, #required,
430 * #children, #type, #name.
432 function template_preprocess_form_element(&$variables) {
433 $element = &$variables['element'];
435 // This function is invoked as theme wrapper, but the rendered form element
436 // may not necessarily have been processed by
437 // \Drupal::formBuilder()->doBuildForm().
439 '#title_display' => 'before',
440 '#wrapper_attributes' => [],
441 '#label_attributes' => [],
443 $variables['attributes'] = $element['#wrapper_attributes'];
445 // Add element #id for #type 'item'.
446 if (isset($element['#markup']) && !empty($element['#id'])) {
447 $variables['attributes']['id'] = $element['#id'];
450 // Pass elements #type and #name to template.
451 if (!empty($element['#type'])) {
452 $variables['type'] = $element['#type'];
454 if (!empty($element['#name'])) {
455 $variables['name'] = $element['#name'];
458 // Pass elements disabled status to template.
459 $variables['disabled'] = !empty($element['#attributes']['disabled']) ? $element['#attributes']['disabled'] : NULL;
461 // Suppress error messages.
462 $variables['errors'] = NULL;
464 // If #title is not set, we don't display any label.
465 if (!isset($element['#title'])) {
466 $element['#title_display'] = 'none';
469 $variables['title_display'] = $element['#title_display'];
471 $variables['prefix'] = isset($element['#field_prefix']) ? $element['#field_prefix'] : NULL;
472 $variables['suffix'] = isset($element['#field_suffix']) ? $element['#field_suffix'] : NULL;
474 $variables['description'] = NULL;
475 if (!empty($element['#description'])) {
476 $variables['description_display'] = $element['#description_display'];
477 $description_attributes = [];
478 if (!empty($element['#id'])) {
479 $description_attributes['id'] = $element['#id'] . '--description';
481 $variables['description']['attributes'] = new Attribute($description_attributes);
482 $variables['description']['content'] = $element['#description'];
485 // Add label_display and label variables to template.
486 $variables['label_display'] = $element['#title_display'];
487 $variables['label'] = ['#theme' => 'form_element_label'];
488 $variables['label'] += array_intersect_key($element, array_flip(['#id', '#required', '#title', '#title_display']));
489 $variables['label']['#attributes'] = $element['#label_attributes'];
491 $variables['children'] = $element['#children'];
495 * Prepares variables for form label templates.
497 * Form element labels include the #title and a #required marker. The label is
498 * associated with the element itself by the element #id. Labels may appear
499 * before or after elements, depending on form-element.html.twig and
502 * This function will not be called for elements with no labels, depending on
503 * #title_display. For elements that have an empty #title and are not required,
504 * this function will output no label (''). For required elements that have an
505 * empty #title, this will output the required marker alone within the label.
506 * The label will use the #id to associate the marker with the field that is
507 * required. That is especially important for screenreader users to know
508 * which field is required.
510 * @param array $variables
511 * An associative array containing:
512 * - element: An associative array containing the properties of the element.
513 * Properties used: #required, #title, #id, #value, #description.
515 function template_preprocess_form_element_label(&$variables) {
516 $element = $variables['element'];
517 // If title and required marker are both empty, output no label.
518 if (isset($element['#title']) && $element['#title'] !== '') {
519 $variables['title'] = ['#markup' => $element['#title']];
522 // Pass elements title_display to template.
523 $variables['title_display'] = $element['#title_display'];
525 // A #for property of a dedicated #type 'label' element as precedence.
526 if (!empty($element['#for'])) {
527 $variables['attributes']['for'] = $element['#for'];
528 // A custom #id allows the referenced form input element to refer back to
529 // the label element; e.g., in the 'aria-labelledby' attribute.
530 if (!empty($element['#id'])) {
531 $variables['attributes']['id'] = $element['#id'];
534 // Otherwise, point to the #id of the form input element.
535 elseif (!empty($element['#id'])) {
536 $variables['attributes']['for'] = $element['#id'];
539 // Pass elements required to template.
540 $variables['required'] = !empty($element['#required']) ? $element['#required'] : NULL;
544 * @defgroup batch Batch operations
546 * Creates and processes batch operations.
548 * Functions allowing forms processing to be spread out over several page
549 * requests, thus ensuring that the processing does not get interrupted
550 * because of a PHP timeout, while allowing the user to receive feedback
551 * on the progress of the ongoing operations.
553 * The API is primarily designed to integrate nicely with the Form API
554 * workflow, but can also be used by non-Form API scripts (like update.php)
555 * or even simple page callbacks (which should probably be used sparingly).
560 * 'title' => t('Exporting'),
561 * 'operations' => array(
562 * array('my_function_1', array($account->id(), 'story')),
563 * array('my_function_2', array()),
565 * 'finished' => 'my_finished_callback',
566 * 'file' => 'path_to_file_containing_myfunctions',
569 * // Only needed if not inside a form _submit handler.
570 * // Setting redirect in batch_process.
571 * batch_process('node/1');
574 * Note: if the batch 'title', 'init_message', 'progress_message', or
575 * 'error_message' could contain any user input, it is the responsibility of
576 * the code calling batch_set() to sanitize them first with a function like
577 * \Drupal\Component\Utility\Html::escape() or
578 * \Drupal\Component\Utility\Xss::filter(). Furthermore, if the batch operation
579 * returns any user input in the 'results' or 'message' keys of $context, it
580 * must also sanitize them first.
582 * Sample callback_batch_operation():
584 * // Simple and artificial: load a node of a given type for a given user
585 * function my_function_1($uid, $type, &$context) {
586 * // The $context array gathers batch context information about the execution (read),
587 * // as well as 'return values' for the current operation (write)
588 * // The following keys are provided :
589 * // 'results' (read / write): The array of results gathered so far by
590 * // the batch processing, for the current operation to append its own.
591 * // 'message' (write): A text message displayed in the progress page.
592 * // The following keys allow for multi-step operations :
593 * // 'sandbox' (read / write): An array that can be freely used to
594 * // store persistent data between iterations. It is recommended to
595 * // use this instead of $_SESSION, which is unsafe if the user
596 * // continues browsing in a separate window while the batch is processing.
597 * // 'finished' (write): A float number between 0 and 1 informing
598 * // the processing engine of the completion level for the operation.
599 * // 1 (or no value explicitly set) means the operation is finished
600 * // and the batch processing can continue to the next operation.
602 * $nodes = \Drupal::entityTypeManager()->getStorage('node')
603 * ->loadByProperties(['uid' => $uid, 'type' => $type]);
604 * $node = reset($nodes);
605 * $context['results'][] = $node->id() . ' : ' . Html::escape($node->label());
606 * $context['message'] = Html::escape($node->label());
609 * // A more advanced example is a multi-step operation that loads all rows,
611 * function my_function_2(&$context) {
612 * if (empty($context['sandbox'])) {
613 * $context['sandbox']['progress'] = 0;
614 * $context['sandbox']['current_id'] = 0;
615 * $context['sandbox']['max'] = db_query('SELECT COUNT(DISTINCT id) FROM {example}')->fetchField();
618 * $result = db_select('example')
619 * ->fields('example', array('id'))
620 * ->condition('id', $context['sandbox']['current_id'], '>')
624 * foreach ($result as $row) {
625 * $context['results'][] = $row->id . ' : ' . Html::escape($row->title);
626 * $context['sandbox']['progress']++;
627 * $context['sandbox']['current_id'] = $row->id;
628 * $context['message'] = Html::escape($row->title);
630 * if ($context['sandbox']['progress'] != $context['sandbox']['max']) {
631 * $context['finished'] = $context['sandbox']['progress'] / $context['sandbox']['max'];
636 * Sample callback_batch_finished():
638 * function my_finished_callback($success, $results, $operations) {
639 * // The 'success' parameter means no fatal PHP errors were detected. All
640 * // other error management should be handled using 'results'.
642 * $message = \Drupal::translation()->formatPlural(count($results), 'One post processed.', '@count posts processed.');
645 * $message = t('Finished with an error.');
647 * \Drupal::messenger()->addMessage($message);
648 * // Providing data for the redirected page is done through $_SESSION.
649 * foreach ($results as $result) {
650 * $items[] = t('Loaded node %title.', array('%title' => $result));
652 * $_SESSION['my_batch_results'] = $items;
660 * Batch operations are added as new batch sets. Batch sets are used to spread
661 * processing (primarily, but not exclusively, forms processing) over several
662 * page requests. This helps to ensure that the processing is not interrupted
663 * due to PHP timeouts, while users are still able to receive feedback on the
664 * progress of the ongoing operations. Combining related operations into
665 * distinct batch sets provides clean code independence for each batch set,
666 * ensuring that two or more batches, submitted independently, can be processed
667 * without mutual interference. Each batch set may specify its own set of
668 * operations and results, produce its own UI messages, and trigger its own
669 * 'finished' callback. Batch sets are processed sequentially, with the progress
670 * bar starting afresh for each new set.
672 * @param $batch_definition
673 * An associative array defining the batch, with the following elements (all
674 * are optional except as noted):
675 * - operations: (required) Array of operations to be performed, where each
676 * item is an array consisting of the name of an implementation of
677 * callback_batch_operation() and an array of parameter.
681 * array('callback_batch_operation_1', array($arg1)),
682 * array('callback_batch_operation_2', array($arg2_1, $arg2_2)),
685 * - title: A safe, translated string to use as the title for the progress
686 * page. Defaults to t('Processing').
687 * - init_message: Message displayed while the processing is initialized.
688 * Defaults to t('Initializing.').
689 * - progress_message: Message displayed while processing the batch. Available
690 * placeholders are @current, @remaining, @total, @percentage, @estimate and
691 * @elapsed. Defaults to t('Completed @current of @total.').
692 * - error_message: Message displayed if an error occurred while processing
693 * the batch. Defaults to t('An error has occurred.').
694 * - finished: Name of an implementation of callback_batch_finished(). This is
695 * executed after the batch has completed. This should be used to perform
696 * any result massaging that may be needed, and possibly save data in
697 * $_SESSION for display after final page redirection.
698 * - file: Path to the file containing the definitions of the 'operations' and
699 * 'finished' functions, for instance if they don't reside in the main
700 * .module file. The path should be relative to base_path(), and thus should
701 * be built using drupal_get_path().
702 * - library: An array of batch-specific CSS and JS libraries.
703 * - url_options: options passed to the \Drupal\Core\Url object when
704 * constructing redirect URLs for the batch.
705 * - progressive: A Boolean that indicates whether or not the batch needs to
706 * run progressively. TRUE indicates that the batch will run in more than
707 * one run. FALSE (default) indicates that the batch will finish in a single
709 * - queue: An override of the default queue (with name and class fields
710 * optional). An array containing two elements:
711 * - name: Unique identifier for the queue.
712 * - class: The name of a class that implements
713 * \Drupal\Core\Queue\QueueInterface, including the full namespace but not
714 * starting with a backslash. It must have a constructor with two
715 * arguments: $name and a \Drupal\Core\Database\Connection object.
716 * Typically, the class will either be \Drupal\Core\Queue\Batch or
717 * \Drupal\Core\Queue\BatchMemory. Defaults to Batch if progressive is
718 * TRUE, or to BatchMemory if progressive is FALSE.
720 function batch_set($batch_definition) {
721 if ($batch_definition) {
722 $batch =& batch_get();
724 // Initialize the batch if needed.
728 'has_form_submits' => FALSE,
732 // Base and default properties for the batch set.
741 'title' => t('Processing'),
742 'init_message' => t('Initializing.'),
743 'progress_message' => t('Completed @current of @total.'),
744 'error_message' => t('An error has occurred.'),
746 $batch_set = $init + $batch_definition + $defaults;
748 // Tweak init_message to avoid the bottom of the page flickering down after
750 $batch_set['init_message'] .= '<br/> ';
752 // The non-concurrent workflow of batch execution allows us to save
753 // numberOfItems() queries by handling our own counter.
754 $batch_set['total'] = count($batch_set['operations']);
755 $batch_set['count'] = $batch_set['total'];
757 // Add the set to the batch.
758 if (empty($batch['id'])) {
759 // The batch is not running yet. Simply add the new set.
760 $batch['sets'][] = $batch_set;
763 // The set is being added while the batch is running. Insert the new set
764 // right after the current one to ensure execution order, and store its
765 // operations in a queue.
766 $index = $batch['current_set'] + 1;
767 $slice1 = array_slice($batch['sets'], 0, $index);
768 $slice2 = array_slice($batch['sets'], $index);
769 $batch['sets'] = array_merge($slice1, [$batch_set], $slice2);
770 _batch_populate_queue($batch, $index);
776 * Processes the batch.
778 * This function is generally not needed in form submit handlers;
779 * Form API takes care of batches that were set during form submission.
781 * @param \Drupal\Core\Url|string $redirect
782 * (optional) Either path or Url object to redirect to when the batch has
783 * finished processing. Note that to simply force a batch to (conditionally)
784 * redirect to a custom location after it is finished processing but to
785 * otherwise allow the standard form API batch handling to occur, it is not
786 * necessary to call batch_process() and use this parameter. Instead, make
787 * the batch 'finished' callback return an instance of
788 * \Symfony\Component\HttpFoundation\RedirectResponse, which will be used
789 * automatically by the standard batch processing pipeline (and which takes
790 * precedence over this parameter).
791 * User will be redirected to the page that started the batch if this argument
792 * is omitted and no redirect response was returned by the 'finished'
793 * callback. Any query arguments will be automatically persisted.
794 * @param \Drupal\Core\Url $url
795 * (optional) URL of the batch processing page. Should only be used for
796 * separate scripts like update.php.
797 * @param $redirect_callback
798 * (optional) Specify a function to be called to redirect to the progressive
801 * @return \Symfony\Component\HttpFoundation\RedirectResponse|null
802 * A redirect response if the batch is progressive. No return value otherwise.
804 function batch_process($redirect = NULL, Url $url = NULL, $redirect_callback = NULL) {
805 $batch =& batch_get();
808 // Add process information
811 'progressive' => TRUE,
812 'url' => isset($url) ? $url : Url::fromRoute('system.batch_page.html'),
813 'source_url' => Url::fromRouteMatch(\Drupal::routeMatch())->mergeOptions(['query' => \Drupal::request()->query->all()]),
814 'batch_redirect' => $redirect,
815 'theme' => \Drupal::theme()->getActiveTheme()->getName(),
816 'redirect_callback' => $redirect_callback,
818 $batch += $process_info;
820 // The batch is now completely built. Allow other modules to make changes
821 // to the batch so that it is easier to reuse batch processes in other
823 \Drupal::moduleHandler()->alter('batch', $batch);
825 // Assign an arbitrary id: don't rely on a serial column in the 'batch'
826 // table, since non-progressive batches skip database storage completely.
827 $batch['id'] = db_next_id();
829 // Move operations to a job queue. Non-progressive batches will use a
830 // memory-based queue.
831 foreach ($batch['sets'] as $key => $batch_set) {
832 _batch_populate_queue($batch, $key);
835 // Initiate processing.
836 if ($batch['progressive']) {
837 // Now that we have a batch id, we can generate the redirection link in
838 // the generic error message.
839 /** @var \Drupal\Core\Url $batch_url */
840 $batch_url = $batch['url'];
841 /** @var \Drupal\Core\Url $error_url */
842 $error_url = clone $batch_url;
843 $query_options = $error_url->getOption('query');
844 $query_options['id'] = $batch['id'];
845 $query_options['op'] = 'finished';
846 $error_url->setOption('query', $query_options);
848 $batch['error_message'] = t('Please continue to <a href=":error_url">the error page</a>', [':error_url' => $error_url->toString(TRUE)->getGeneratedUrl()]);
850 // Clear the way for the redirection to the batch processing page, by
851 // saving and unsetting the 'destination', if there is any.
852 $request = \Drupal::request();
853 if ($request->query->has('destination')) {
854 $batch['destination'] = $request->query->get('destination');
855 $request->query->remove('destination');
859 \Drupal::service('batch.storage')->create($batch);
861 // Set the batch number in the session to guarantee that it will stay alive.
862 $_SESSION['batches'][$batch['id']] = TRUE;
864 // Redirect for processing.
865 $query_options = $error_url->getOption('query');
866 $query_options['op'] = 'start';
867 $query_options['id'] = $batch['id'];
868 $batch_url->setOption('query', $query_options);
869 if (($function = $batch['redirect_callback']) && function_exists($function)) {
870 $function($batch_url->toString(), ['query' => $query_options]);
873 return new RedirectResponse($batch_url->setAbsolute()->toString(TRUE)->getGeneratedUrl());
877 // Non-progressive execution: bypass the whole progressbar workflow
878 // and execute the batch in one pass.
879 require_once __DIR__ . '/batch.inc';
886 * Retrieves the current batch.
888 function &batch_get() {
889 // Not drupal_static(), because Batch API operates at a lower level than most
890 // use-cases for resetting static variables, and we specifically do not want a
891 // global drupal_static_reset() resetting the batch information. Functions
892 // that are part of the Batch API and need to reset the batch information may
893 // call batch_get() and manipulate the result by reference. Functions that are
894 // not part of the Batch API can also do this, but shouldn't.
900 * Populates a job queue with the operations of a batch set.
902 * Depending on whether the batch is progressive or not, the
903 * Drupal\Core\Queue\Batch or Drupal\Core\Queue\BatchMemory handler classes will
904 * be used. The name and class of the queue are added by reference to the
910 * The id of the set to process.
912 function _batch_populate_queue(&$batch, $set_id) {
913 $batch_set = &$batch['sets'][$set_id];
915 if (isset($batch_set['operations'])) {
918 'name' => 'drupal_batch:' . $batch['id'] . ':' . $set_id,
919 'class' => $batch['progressive'] ? 'Drupal\Core\Queue\Batch' : 'Drupal\Core\Queue\BatchMemory',
923 $queue = _batch_queue($batch_set);
924 $queue->createQueue();
925 foreach ($batch_set['operations'] as $operation) {
926 $queue->createItem($operation);
929 unset($batch_set['operations']);
934 * Returns a queue object for a batch set.
942 function _batch_queue($batch_set) {
945 if (!isset($queues)) {
949 if (isset($batch_set['queue'])) {
950 $name = $batch_set['queue']['name'];
951 $class = $batch_set['queue']['class'];
953 if (!isset($queues[$class][$name])) {
954 $queues[$class][$name] = new $class($name, \Drupal::database());
956 return $queues[$class][$name];
961 * @} End of "defgroup batch".