CachePluginBase.php in Drupal 8
Same filename and directory in other branches
Namespace
Drupal\views\Plugin\views\cacheFile
core/modules/views/src/Plugin/views/cache/CachePluginBase.phpView source
<?php
namespace Drupal\views\Plugin\views\cache;
use Drupal\Core\Cache\Cache;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\views\Plugin\views\PluginBase;
use Drupal\Core\Database\Query\Select;
use Drupal\views\ResultRow;
/**
* @defgroup views_cache_plugins Views cache plugins
* @{
* Plugins to handle Views caches.
*
* Cache plugins control how caching is done in Views.
*
* Cache plugins extend \Drupal\views\Plugin\views\cache\CachePluginBase.
* They must be annotated with \Drupal\views\Annotation\ViewsCache
* annotation, and must be in namespace directory Plugin\views\cache.
*
* @ingroup views_plugins
* @see plugin_api
*/
/**
* The base plugin to handle caching.
*/
abstract class CachePluginBase extends PluginBase {
/**
* Contains all data that should be written/read from cache.
*/
public $storage = [];
/**
* Which cache bin to store query results in.
*
* @var string
*/
protected $resultsBin = 'data';
/**
* Stores the cache ID used for the results cache.
*
* The cache ID is stored in generateResultsKey() got executed.
*
* @var string
*
* @see \Drupal\views\Plugin\views\cache\CachePluginBase::generateResultsKey()
*/
protected $resultsKey;
/**
* Returns the resultsKey property.
*
* @return string
* The resultsKey property.
*/
public function getResultsKey() {
return $this->resultsKey;
}
/**
* Return a string to display as the clickable title for the
* access control.
*/
public function summaryTitle() {
return $this
->t('Unknown');
}
/**
* Determine the expiration time of the cache type, or NULL if no expire.
*
* Plugins must override this to implement expiration.
*
* @param $type
* The cache type, either 'query', 'result'.
*/
protected function cacheExpire($type) {
}
/**
* Determine expiration time in the cache table of the cache type
* or CACHE_PERMANENT if item shouldn't be removed automatically from cache.
*
* Plugins must override this to implement expiration in the cache table.
*
* @param $type
* The cache type, either 'query', 'result'.
*/
protected function cacheSetMaxAge($type) {
return Cache::PERMANENT;
}
/**
* Save data to the cache.
*
* A plugin should override this to provide specialized caching behavior.
*
* @param $type
* The cache type, either 'query', 'result'.
*/
public function cacheSet($type) {
switch ($type) {
case 'query':
// Not supported currently, but this is certainly where we'd put it.
break;
case 'results':
$data = [
'result' => $this
->prepareViewResult($this->view->result),
'total_rows' => isset($this->view->total_rows) ? $this->view->total_rows : 0,
'current_page' => $this->view
->getCurrentPage(),
];
$expire = $this
->cacheSetMaxAge($type) === Cache::PERMANENT ? Cache::PERMANENT : (int) $this->view
->getRequest()->server
->get('REQUEST_TIME') + $this
->cacheSetMaxAge($type);
\Drupal::cache($this->resultsBin)
->set($this
->generateResultsKey(), $data, $expire, $this
->getCacheTags());
break;
}
}
/**
* Retrieve data from the cache.
*
* A plugin should override this to provide specialized caching behavior.
*
* @param $type
* The cache type, either 'query', 'result'.
*
* @return bool
* TRUE if data has been taken from the cache, otherwise FALSE.
*/
public function cacheGet($type) {
$cutoff = $this
->cacheExpire($type);
switch ($type) {
case 'query':
// Not supported currently, but this is certainly where we'd put it.
return FALSE;
case 'results':
// Values to set: $view->result, $view->total_rows, $view->execute_time,
// $view->current_page.
if ($cache = \Drupal::cache($this->resultsBin)
->get($this
->generateResultsKey())) {
if (!$cutoff || $cache->created > $cutoff) {
$this->view->result = $cache->data['result'];
// Load entities for each result.
$this->view->query
->loadEntities($this->view->result);
$this->view->total_rows = $cache->data['total_rows'];
$this->view
->setCurrentPage($cache->data['current_page'], TRUE);
$this->view->execute_time = 0;
return TRUE;
}
}
return FALSE;
}
}
/**
* Clear out cached data for a view.
*/
public function cacheFlush() {
Cache::invalidateTags($this->view->storage
->getCacheTagsToInvalidate());
}
/**
* Post process any rendered data.
*
* This can be valuable to be able to cache a view and still have some level
* of dynamic output. In an ideal world, the actual output will include HTML
* comment based tokens, and then the post process can replace those tokens.
*
* Example usage. If it is known that the view is a node view and that the
* primary field will be a nid, you can do something like this:
* @code
* <!--post-FIELD-NID-->
* @endcode
*
* And then in the post render, create an array with the text that should
* go there:
*
* @code
* strtr($output, array('<!--post-FIELD-1-->', 'output for FIELD of nid 1');
* @endcode
*
* All of the cached result data will be available in $view->result, as well,
* so all ids used in the query should be discoverable.
*/
public function postRender(&$output) {
}
/**
* Calculates and sets a cache ID used for the result cache.
*
* @return string
* The generated cache ID.
*/
public function generateResultsKey() {
if (!isset($this->resultsKey)) {
$build_info = $this->view->build_info;
foreach ([
'query',
'count_query',
] as $index) {
// If the default query back-end is used generate SQL query strings from
// the query objects.
if ($build_info[$index] instanceof Select) {
$query = clone $build_info[$index];
$query
->preExecute();
$build_info[$index] = [
'query' => (string) $query,
'arguments' => $query
->getArguments(),
];
}
}
$key_data = [
'build_info' => $build_info,
];
// @todo https://www.drupal.org/node/2433591 might solve it to not require
// the pager information here.
$key_data['pager'] = [
'page' => $this->view
->getCurrentPage(),
'items_per_page' => $this->view
->getItemsPerPage(),
'offset' => $this->view
->getOffset(),
];
$key_data += \Drupal::service('cache_contexts_manager')
->convertTokensToKeys($this->displayHandler
->getCacheMetadata()
->getCacheContexts())
->getKeys();
$this->resultsKey = $this->view->storage
->id() . ':' . $this->displayHandler->display['id'] . ':results:' . hash('sha256', serialize($key_data));
}
return $this->resultsKey;
}
/**
* Gets an array of cache tags for the current view.
*
* @return string[]
* An array of cache tags based on the current view.
*/
public function getCacheTags() {
$tags = $this->view->storage
->getCacheTags();
// The list cache tags for the entity types listed in this view.
$entity_information = $this->view
->getQuery()
->getEntityTableInfo();
if (!empty($entity_information)) {
// Add the list cache tags for each entity type used by this view.
foreach ($entity_information as $table => $metadata) {
$tags = Cache::mergeTags($tags, \Drupal::entityTypeManager()
->getDefinition($metadata['entity_type'])
->getListCacheTags());
}
}
$tags = Cache::mergeTags($tags, $this->view
->getQuery()
->getCacheTags());
return $tags;
}
/**
* Gets the max age for the current view.
*
* @return int
*/
public function getCacheMaxAge() {
$max_age = $this
->getDefaultCacheMaxAge();
$max_age = Cache::mergeMaxAges($max_age, $this->view
->getQuery()
->getCacheMaxAge());
return $max_age;
}
/**
* Returns the default cache max age.
*/
protected function getDefaultCacheMaxAge() {
// The default cache backend is not caching anything.
return 0;
}
/**
* Prepares the view result before putting it into cache.
*
* @param \Drupal\views\ResultRow[] $result
* The result containing loaded entities.
*
* @return \Drupal\views\ResultRow[]
* The result without loaded entities.
*/
protected function prepareViewResult(array $result) {
$return = [];
// Clone each row object and remove any loaded entities, to keep the
// original result rows intact.
foreach ($result as $key => $row) {
$clone = clone $row;
$clone
->resetEntityData();
$return[$key] = $clone;
}
return $return;
}
/**
* Alters the cache metadata of a display upon saving a view.
*
* @param \Drupal\Core\Cache\CacheableMetadata $cache_metadata
* The cache metadata.
*/
public function alterCacheMetadata(CacheableMetadata $cache_metadata) {
}
/**
* Returns the row cache tags.
*
* @param \Drupal\views\ResultRow $row
* A result row.
*
* @return string[]
* The row cache tags.
*/
public function getRowCacheTags(ResultRow $row) {
$tags = !empty($row->_entity) ? $row->_entity
->getCacheTags() : [];
if (!empty($row->_relationship_entities)) {
foreach ($row->_relationship_entities as $entity) {
$tags = Cache::mergeTags($tags, $entity
->getCacheTags());
}
}
return $tags;
}
/**
* Returns the row cache keys.
*
* @param \Drupal\views\ResultRow $row
* A result row.
*
* @return string[]
* The row cache keys.
*/
public function getRowCacheKeys(ResultRow $row) {
return [
'views',
'fields',
$this->view
->id(),
$this->view->current_display,
$this
->getRowId($row),
];
}
/**
* Returns a unique identifier for the specified row.
*
* @param \Drupal\views\ResultRow $row
* A result row.
*
* @return string
* The row identifier.
*/
public function getRowId(ResultRow $row) {
// Here we compute a unique identifier for the row by computing the hash of
// its data. We exclude the current index, since the same row could have a
// different result index depending on the user permissions. We exclude also
// entity data, since serializing entity objects is very expensive. Instead
// we include entity cache tags, which are enough to identify all the
// entities associated with the row.
$row_data = array_diff_key((array) $row, array_flip([
'index',
'_entity',
'_relationship_entities',
])) + $this
->getRowCacheTags($row);
// This ensures that we get a unique identifier taking field handler access
// into account: users having access to different sets of fields will get
// different row identifiers.
$field_ids = array_keys($this->view->field);
$row_data += array_flip($field_ids);
// Finally we compute a hash of row data and return it as row identifier.
return hash('sha256', serialize($row_data));
}
}
/**
* @}
*/
Classes
Name | Description |
---|---|
CachePluginBase | The base plugin to handle caching. |