diff core/modules/views/views.api.php @ 0:4c8ae668cc8c

Initial import (non-working)

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/core/modules/views/views.api.php	Wed Nov 29 16:09:58 2017 +0000
@@ -0,0 +1,1270 @@
+<?php
+
+/**
+ * @file
+ * Describes hooks and plugins provided by the Views module.
+ */
+
+use Drupal\Core\Language\LanguageInterface;
+use Drupal\views\Plugin\views\cache\CachePluginBase;
+use Drupal\views\Plugin\views\PluginBase;
+use Drupal\views\ViewExecutable;
+
+/**
+ * @defgroup views_overview Views overview
+ * @{
+ * Overview of the Views module API
+ *
+ * The Views module is a generalized query and display engine, which can be used
+ * to make views (formatted lists, grids, feeds, and other output) of items
+ * (often entities, but can be other types of data). Developers can interact
+ * with Views in several ways:
+ * - Provide plugins: Views plugins govern nearly every aspect of views,
+ *   including querying (sorting, filtering, etc.) and display (at several
+ *   levels of granularity, ranging from the entire view to the details of a
+ *   field). See the @link views_plugins Views plugins topic @endlink for
+ *   more information.
+ * - Provide data: Data types can be provided to Views by implementing
+ *   hook_views_data(), and data types provided by other modules can be altered
+ *   by implementing hook_views_data_alter(). To provide views data for an
+ *   entity, create a class implementing
+ *   \Drupal\views\EntityViewsDataInterface and reference this in the
+ *   "views_data" annotation in the entity class. You can autogenerate big parts
+ *   of the integration if you extend the \Drupal\views\EntityViewsData base
+ *   class. See the @link entity_api Entity API topic @endlink for more
+ *   information about entities.
+ * - Implement hooks: A few operations in Views can be influenced by hooks.
+ *   See the @link views_hooks Views hooks topic @endlink for a list.
+ * - Theming: See the @link views_templates Views templates topic @endlink
+ *   for more information.
+ *
+ * @see \Drupal\views\ViewExecutable
+ * @see \Drupal\views\Views
+ * @}
+ */
+
+/**
+ * @defgroup views_plugins Views plugins
+ * @{
+ * Overview of views plugins
+ *
+ * Views plugins are objects that are used to build and render the view.
+ * See individual views plugin topics for more information about the
+ * specifics of each plugin type, and the
+ * @link plugin_api Plugin API topic @endlink for more information about
+ * plugins in general.
+ *
+ * Some Views plugins are known as handlers. Handler plugins help build the
+ * view query object: filtering, contextual filtering, sorting, relationships,
+ * etc.
+ *
+ * @todo Document specific options on the appropriate plugin base classes.
+ * @todo Add examples.
+ *
+ * @ingroup views_overview
+ * @see \Drupal\views\Plugin\views\PluginBase
+ * @see \Drupal\views\Plugin\views\HandlerBase
+ * @see plugin_api
+ * @see annotation
+ * @}
+ */
+
+/**
+ * @defgroup views_hooks Views hooks
+ * @{
+ * Hooks that allow other modules to implement the Views API.
+ * @ingroup views_overview
+ * @}
+ */
+
+/**
+ * @addtogroup hooks
+ * @{
+ */
+
+/**
+ * Analyze a view to provide warnings about its configuration.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view being executed.
+ *
+ * @return array
+ *   Array of warning messages built by Analyzer::formatMessage to be displayed
+ *   to the user following analysis of the view.
+ */
+function hook_views_analyze(Drupal\views\ViewExecutable $view) {
+  $messages = [];
+
+  if ($view->display_handler->options['pager']['type'] == 'none') {
+    $messages[] = Drupal\views\Analyzer::formatMessage(t('This view has no pager. This could cause performance issues when the view contains many items.'), 'warning');
+  }
+
+  return $messages;
+}
+
+/**
+ * Describe data tables and fields (or the equivalent) to Views.
+ *
+ * The table and fields are processed in Views using various plugins. See
+ * the @link views_plugins Views plugins topic @endlink for more information.
+ *
+ * To provide views data for an entity, instead of implementing this hook,
+ * create a class implementing \Drupal\views\EntityViewsDataInterface and
+ * reference this in the "views" annotation in the entity class. The return
+ * value of the getViewsData() method on the interface is the same as this hook,
+ * and base class in \Drupal\views\EntityViewsData will take care of adding the
+ * basic Views tables and fields for your entity. See the
+ * @link entity_api Entity API topic @endlink for more information about
+ * entities.
+ *
+ * The data described with this hook is fetched and retrieved by
+ * \Drupal\views\Views::viewsData()->get().
+ *
+ * @return array
+ *   An associative array describing the structure of database tables and fields
+ *   (and their equivalents) provided for use in Views. At the outermost level,
+ *   the keys are the names used internally by Views for the tables (usually the
+ *   actual table name). Each table's array describes the table itself, how to
+ *   join to other tables, and the fields that are part of the table. The sample
+ *   function body provides documentation of the details.
+ *
+ * @see hook_views_data_alter()
+ */
+function hook_views_data() {
+  // This example describes how to write hook_views_data() for a table defined
+  // like this:
+  // CREATE TABLE example_table (
+  //   nid INT(11) NOT NULL         COMMENT 'Primary key: {node}.nid.',
+  //   plain_text_field VARCHAR(32) COMMENT 'Just a plain text field.',
+  //   numeric_field INT(11)        COMMENT 'Just a numeric field.',
+  //   boolean_field INT(1)         COMMENT 'Just an on/off field.',
+  //   timestamp_field INT(8)       COMMENT 'Just a timestamp field.',
+  //   langcode VARCHAR(12)         COMMENT 'Language code field.',
+  //   PRIMARY KEY(nid)
+  // );
+
+  // Define the return array.
+  $data = [];
+
+  // The outermost keys of $data are Views table names, which should usually
+  // be the same as the hook_schema() table names.
+  $data['example_table'] = [];
+
+  // The value corresponding to key 'table' gives properties of the table
+  // itself.
+  $data['example_table']['table'] = [];
+
+  // Within 'table', the value of 'group' (translated string) is used as a
+  // prefix in Views UI for this table's fields, filters, etc. When adding
+  // a field, filter, etc. you can also filter by the group.
+  $data['example_table']['table']['group'] = t('Example table');
+
+  // Within 'table', the value of 'provider' is the module that provides schema
+  // or the entity type that causes the table to exist. Setting this ensures
+  // that views have the correct dependencies. This is automatically set to the
+  // module that implements hook_views_data().
+  $data['example_table']['table']['provider'] = 'example_module';
+
+  // Some tables are "base" tables, meaning that they can be the base tables
+  // for views. Non-base tables can only be brought in via relationships in
+  // views based on other tables. To define a table to be a base table, add
+  // key 'base' to the 'table' array:
+  $data['example_table']['table']['base'] = [
+    // Identifier (primary) field in this table for Views.
+    'field' => 'nid',
+    // Label in the UI.
+    'title' => t('Example table'),
+    // Longer description in the UI. Required.
+    'help' => t('Example table contains example content and can be related to nodes.'),
+    'weight' => -10,
+  ];
+
+  // Some tables have an implicit, automatic relationship to other tables,
+  // meaning that when the other table is available in a view (either as the
+  // base table or through a relationship), this table's fields, filters, etc.
+  // are automatically made available without having to add an additional
+  // relationship. To define an implicit relationship that will make your
+  // table automatically available when another table is present, add a 'join'
+  // section to your 'table' section. Note that it is usually only a good idea
+  // to do this for one-to-one joins, because otherwise your automatic join
+  // will add more rows to the view. It is also not a good idea to do this if
+  // most views won't need your table -- if that is the case, define a
+  // relationship instead (see below).
+  //
+  // If you've decided an automatic join is a good idea, here's how to do it;
+  // the resulting SQL query will look something like this:
+  //   ... FROM example_table et ... JOIN node_field_data nfd
+  //   ON et.nid = nfd.nid AND ('extra' clauses will be here) ...
+  // although the table aliases will be different.
+  $data['example_table']['table']['join'] = [
+    // Within the 'join' section, list one or more tables to automatically
+    // join to. In this example, every time 'node_field_data' is available in
+    // a view, 'example_table' will be too. The array keys here are the array
+    // keys for the other tables, given in their hook_views_data()
+    // implementations. If the table listed here is from another module's
+    // hook_views_data() implementation, make sure your module depends on that
+    // other module.
+    'node_field_data' => [
+      // Primary key field in node_field_data to use in the join.
+      'left_field' => 'nid',
+      // Foreign key field in example_table to use in the join.
+      'field' => 'nid',
+      // 'extra' is an array of additional conditions on the join.
+      'extra' => [
+        0 => [
+          // Adds AND node_field_data.published = TRUE to the join.
+          'field' => 'published',
+          'value' => TRUE,
+        ],
+        1 => [
+          // Adds AND example_table.numeric_field = 1 to the join.
+          'left_field' => 'numeric_field',
+          'value' => 1,
+          // If true, the value will not be surrounded in quotes.
+          'numeric' => TRUE,
+        ],
+        2 => [
+          // Adds AND example_table.boolean_field <>
+          // node_field_data.published to the join.
+          'field' => 'published',
+          'left_field' => 'boolean_field',
+          // The operator used, Defaults to "=".
+          'operator' => '!=',
+        ],
+      ],
+    ],
+  ];
+
+  // You can also do a more complex join, where in order to get to a certain
+  // base table defined in a hook_views_data() implementation, you will join
+  // to a different table that Views knows how to auto-join to the base table.
+  // For instance, if another module that your module depends on had
+  // defined a table 'foo' with an automatic join to 'node_field_table' (as
+  // shown above), you could join to 'node_field_table' via the 'foo' table.
+  // Here's how to do this, and the resulting SQL query would look something
+  // like this:
+  //   ... FROM example_table et ... JOIN foo foo
+  //   ON et.nid = foo.nid AND ('extra' clauses will be here) ...
+  //   JOIN node_field_data nfd ON (definition of the join from the foo
+  //   module goes here) ...
+  // although the table aliases will be different.
+  $data['example_table']['table']['join']['node_field_data'] = [
+    // 'node_field_data' above is the base we're joining to in Views.
+    // 'left_table' is the table we're actually joining to, in order to get to
+    // 'node_field_data'. It has to be something that Views knows how to join
+    // to 'node_field_data'.
+    'left_table' => 'foo',
+    'left_field' => 'nid',
+    'field' => 'nid',
+    // 'extra' is an array of additional conditions on the join.
+    'extra' => [
+      // This syntax matches additional fields in the two tables:
+      // ... AND foo.langcode = example_table.langcode ...
+      ['left_field' => 'langcode', 'field' => 'langcode'],
+      // This syntax adds a condition on our table. 'operator' defaults to
+      // '=' for non-array values, or 'IN' for array values.
+      // ... AND example_table.numeric_field > 0 ...
+      ['field' => 'numeric_field', 'value' => 0, 'numeric' => TRUE, 'operator' => '>'],
+    ],
+  ];
+
+  // Other array elements at the top level of your table's array describe
+  // individual database table fields made available to Views. The array keys
+  // are the names (unique within the table) used by Views for the fields,
+  // usually equal to the database field names.
+  //
+  // Each field entry must have the following elements:
+  // - title: Translated label for the field in the UI.
+  // - help: Description of the field in the UI.
+  //
+  // Each field entry may also have one or more of the following elements,
+  // describing "handlers" (plugins) for the field:
+  // - relationship: Specifies a handler that allows this field to be used
+  //   to define a relationship to another table in Views.
+  // - field: Specifies a handler to make it available to Views as a field.
+  // - filter: Specifies a handler to make it available to Views as a filter.
+  // - sort: Specifies a handler to make it available to Views as a sort.
+  // - argument: Specifies a handler to make it available to Views as an
+  //   argument, or contextual filter as it is known in the UI.
+  // - area: Specifies a handler to make it available to Views to add content
+  //   to the header, footer, or as no result behavior.
+  //
+  // Note that when specifying handlers, you must give the handler plugin ID
+  // and you may also specify overrides for various settings that make up the
+  // plugin definition. See examples below; the Boolean example demonstrates
+  // setting overrides.
+
+  // Node ID field, exposed as relationship only, since it is a foreign key
+  // in this table.
+  $data['example_table']['nid'] = [
+    'title' => t('Example content'),
+    'help' => t('Relate example content to the node content'),
+
+    // Define a relationship to the node_field_data table, so views whose
+    // base table is example_table can add a relationship to nodes. To make a
+    // relationship in the other direction, you can:
+    // - Use hook_views_data_alter() -- see the function body example on that
+    //   hook for details.
+    // - Use the implicit join method described above.
+    'relationship' => [
+      // Views name of the table to join to for the relationship.
+      'base' => 'node_field_data',
+      // Database field name in the other table to join on.
+      'base field' => 'nid',
+      // ID of relationship handler plugin to use.
+      'id' => 'standard',
+      // Default label for relationship in the UI.
+      'label' => t('Example node'),
+    ],
+  ];
+
+  // Plain text field, exposed as a field, sort, filter, and argument.
+  $data['example_table']['plain_text_field'] = [
+    'title' => t('Plain text field'),
+    'help' => t('Just a plain text field.'),
+
+    'field' => [
+      // ID of field handler plugin to use.
+      'id' => 'standard',
+    ],
+
+    'sort' => [
+      // ID of sort handler plugin to use.
+      'id' => 'standard',
+    ],
+
+    'filter' => [
+      // ID of filter handler plugin to use.
+      'id' => 'string',
+    ],
+
+    'argument' => [
+      // ID of argument handler plugin to use.
+      'id' => 'string',
+    ],
+  ];
+
+  // Numeric field, exposed as a field, sort, filter, and argument.
+  $data['example_table']['numeric_field'] = [
+    'title' => t('Numeric field'),
+    'help' => t('Just a numeric field.'),
+
+    'field' => [
+      // ID of field handler plugin to use.
+      'id' => 'numeric',
+    ],
+
+    'sort' => [
+      // ID of sort handler plugin to use.
+      'id' => 'standard',
+    ],
+
+    'filter' => [
+      // ID of filter handler plugin to use.
+      'id' => 'numeric',
+    ],
+
+    'argument' => [
+      // ID of argument handler plugin to use.
+      'id' => 'numeric',
+    ],
+  ];
+
+  // Boolean field, exposed as a field, sort, and filter. The filter section
+  // illustrates overriding various settings.
+  $data['example_table']['boolean_field'] = [
+    'title' => t('Boolean field'),
+    'help' => t('Just an on/off field.'),
+
+    'field' => [
+      // ID of field handler plugin to use.
+      'id' => 'boolean',
+    ],
+
+    'sort' => [
+      // ID of sort handler plugin to use.
+      'id' => 'standard',
+    ],
+
+    'filter' => [
+      // ID of filter handler plugin to use.
+      'id' => 'boolean',
+      // Override the generic field title, so that the filter uses a different
+      // label in the UI.
+      'label' => t('Published'),
+      // Override the default BooleanOperator filter handler's 'type' setting,
+      // to display this as a "Yes/No" filter instead of a "True/False" filter.
+      'type' => 'yes-no',
+      // Override the default Boolean filter handler's 'use_equal' setting, to
+      // make the query use 'boolean_field = 1' instead of 'boolean_field <> 0'.
+      'use_equal' => TRUE,
+    ],
+  ];
+
+  // Integer timestamp field, exposed as a field, sort, and filter.
+  $data['example_table']['timestamp_field'] = [
+    'title' => t('Timestamp field'),
+    'help' => t('Just a timestamp field.'),
+
+    'field' => [
+      // ID of field handler plugin to use.
+      'id' => 'date',
+    ],
+
+    'sort' => [
+      // ID of sort handler plugin to use.
+      'id' => 'date',
+    ],
+
+    'filter' => [
+      // ID of filter handler plugin to use.
+      'id' => 'date',
+    ],
+  ];
+
+  // Area example. Areas are not generally associated with actual data
+  // tables and fields. This example is from views_views_data(), which defines
+  // the "Global" table (not really a table, but a group of Fields, Filters,
+  // etc. that are grouped into section "Global" in the UI). Here's the
+  // definition of the generic "Text area":
+  $data['views']['area'] = [
+    'title' => t('Text area'),
+    'help' => t('Provide markup text for the area.'),
+    'area' => [
+      // ID of the area handler plugin to use.
+      'id' => 'text',
+    ],
+  ];
+
+  return $data;
+}
+
+/**
+ * Alter the table and field information from hook_views_data().
+ *
+ * @param array $data
+ *   An array of all information about Views tables and fields, collected from
+ *   hook_views_data(), passed by reference.
+ *
+ * @see hook_views_data()
+ */
+function hook_views_data_alter(array &$data) {
+  // Alter the title of the node_field_data:nid field in the Views UI.
+  $data['node_field_data']['nid']['title'] = t('Node-Nid');
+
+  // Add an additional field to the users_field_data table.
+  $data['users_field_data']['example_field'] = [
+    'title' => t('Example field'),
+    'help' => t('Some example content that references a user'),
+
+    'field' => [
+      // ID of the field handler to use.
+      'id' => 'example_field',
+    ],
+  ];
+
+  // Change the handler of the node title field, presumably to a handler plugin
+  // you define in your module. Give the ID of this plugin.
+  $data['node_field_data']['title']['field']['id'] = 'node_title';
+
+  // Add a relationship that will allow a view whose base table is 'foo' (from
+  // another module) to have a relationship to 'example_table' (from my module),
+  // via joining foo.fid to example_table.eid.
+  //
+  // This relationship has to be added to the 'foo' Views data, which my module
+  // does not control, so it must be done in hook_views_data_alter(), not
+  // hook_views_data().
+  //
+  // In Views data definitions, each field can have only one relationship. So
+  // rather than adding this relationship directly to the $data['foo']['fid']
+  // field entry, which could overwrite an existing relationship, we define
+  // a dummy field key to handle the relationship.
+  $data['foo']['unique_dummy_name'] = [
+    'title' => t('Title seen while adding relationship'),
+    'help' => t('More information about the relationship'),
+
+    'relationship' => [
+      // Views name of the table being joined to from foo.
+      'base' => 'example_table',
+      // Database field name in example_table for the join.
+      'base field' => 'eid',
+      // Real database field name in foo for the join, to override
+      // 'unique_dummy_name'.
+      'field' => 'fid',
+      // ID of relationship handler plugin to use.
+      'id' => 'standard',
+      'label' => t('Default label for relationship'),
+    ],
+  ];
+
+  // Note that the $data array is not returned – it is modified by reference.
+}
+
+/**
+ * Override the default Views data for a Field API field.
+ *
+ * The field module's implementation of hook_views_data() invokes this for each
+ * field storage, in the module that defines the field type. It is not invoked
+ * in other modules.
+ *
+ * If no hook implementation exists, hook_views_data() falls back to
+ * views_field_default_views_data().
+ *
+ * @param \Drupal\field\FieldStorageConfigInterface $field_storage
+ *   The field storage config entity.
+ *
+ * @return array
+ *   An array of views data, in the same format as the return value of
+ *   hook_views_data().
+ *
+ * @see views_views_data()
+ * @see hook_field_views_data_alter()
+ * @see hook_field_views_data_views_data_alter()
+ */
+function hook_field_views_data(\Drupal\field\FieldStorageConfigInterface $field_storage) {
+  $data = views_field_default_views_data($field_storage);
+  foreach ($data as $table_name => $table_data) {
+    // Add the relationship only on the target_id field.
+    $data[$table_name][$field_storage->getName() . '_target_id']['relationship'] = [
+      'id' => 'standard',
+      'base' => 'file_managed',
+      'base field' => 'target_id',
+      'label' => t('image from @field_name', ['@field_name' => $field_storage->getName()]),
+    ];
+  }
+
+  return $data;
+}
+
+/**
+ * Alter the Views data for a single Field API field.
+ *
+ * This is called on all modules even if there is no hook_field_views_data()
+ * implementation for the field, and therefore may be used to alter the
+ * default data that views_field_default_views_data() supplies for the
+ * field storage.
+ *
+ * @param array $data
+ *   The views data for the field storage. This has the same format as the
+ *   return value of hook_views_data().
+ * @param \Drupal\field\FieldStorageConfigInterface $field_storage
+ *   The field storage config entity.
+ *
+ * @see views_views_data()
+ * @see hook_field_views_data()
+ * @see hook_field_views_data_views_data_alter()
+ */
+function hook_field_views_data_alter(array &$data, \Drupal\field\FieldStorageConfigInterface $field_storage) {
+  $entity_type_id = $field_storage->getTargetEntityTypeId();
+  $field_name = $field_storage->getName();
+  $entity_type = \Drupal::entityManager()->getDefinition($entity_type_id);
+  $pseudo_field_name = 'reverse_' . $field_name . '_' . $entity_type_id;
+  $table_mapping = \Drupal::entityManager()->getStorage($entity_type_id)->getTableMapping();
+
+  list($label) = views_entity_field_label($entity_type_id, $field_name);
+
+  $data['file_managed'][$pseudo_field_name]['relationship'] = [
+    'title' => t('@entity using @field', ['@entity' => $entity_type->getLabel(), '@field' => $label]),
+    'help' => t('Relate each @entity with a @field set to the image.', ['@entity' => $entity_type->getLabel(), '@field' => $label]),
+    'id' => 'entity_reverse',
+    'field_name' => $field_name,
+    'entity_type' => $entity_type_id,
+    'field table' => $table_mapping->getDedicatedDataTableName($field_storage),
+    'field field' => $field_name . '_target_id',
+    'base' => $entity_type->getBaseTable(),
+    'base field' => $entity_type->getKey('id'),
+    'label' => $field_name,
+    'join_extra' => [
+      0 => [
+        'field' => 'deleted',
+        'value' => 0,
+        'numeric' => TRUE,
+      ],
+    ],
+  ];
+}
+
+/**
+ * Alter the Views data on a per field basis.
+ *
+ * The field module's implementation of hook_views_data_alter() invokes this for
+ * each field storage, in the module that defines the field type. It is not
+ * invoked in other modules.
+ *
+ * Unlike hook_field_views_data_alter(), this operates on the whole of the views
+ * data. This allows a field type to add data that concerns its fields in
+ * other tables, which would not yet be defined at the point when
+ * hook_field_views_data() and hook_field_views_data_alter() are invoked. For
+ * example, entityreference adds reverse relationships on the tables for the
+ * entities which are referenced by entityreference fields.
+ *
+ * (Note: this is weirdly named so as not to conflict with
+ * hook_field_views_data_alter().)
+ *
+ * @param array $data
+ *   The views data.
+ * @param \Drupal\field\FieldStorageConfigInterface $field
+ *   The field storage config entity.
+ *
+ * @see hook_field_views_data()
+ * @see hook_field_views_data_alter()
+ * @see views_views_data_alter()
+ */
+function hook_field_views_data_views_data_alter(array &$data, \Drupal\field\FieldStorageConfigInterface $field) {
+  $field_name = $field->getName();
+  $data_key = 'field_data_' . $field_name;
+  $entity_type_id = $field->entity_type;
+  $entity_type = \Drupal::entityManager()->getDefinition($entity_type_id);
+  $pseudo_field_name = 'reverse_' . $field_name . '_' . $entity_type_id;
+  list($label) = views_entity_field_label($entity_type_id, $field_name);
+  $table_mapping = \Drupal::entityManager()->getStorage($entity_type_id)->getTableMapping();
+
+  // Views data for this field is in $data[$data_key].
+  $data[$data_key][$pseudo_field_name]['relationship'] = [
+    'title' => t('@entity using @field', ['@entity' => $entity_type->getLabel(), '@field' => $label]),
+    'help' => t('Relate each @entity with a @field set to the term.', ['@entity' => $entity_type->getLabel(), '@field' => $label]),
+    'id' => 'entity_reverse',
+    'field_name' => $field_name,
+    'entity_type' => $entity_type_id,
+    'field table' => $table_mapping->getDedicatedDataTableName($field),
+    'field field' => $field_name . '_target_id',
+    'base' => $entity_type->getBaseTable(),
+    'base field' => $entity_type->getKey('id'),
+    'label' => $field_name,
+    'join_extra' => [
+      0 => [
+        'field' => 'deleted',
+        'value' => 0,
+        'numeric' => TRUE,
+      ],
+    ],
+  ];
+}
+
+/**
+ * Replace special strings in the query before it is executed.
+ *
+ * The idea is that certain dynamic values can be placed in a query when it is
+ * built, and substituted at run-time, allowing the query to be cached and
+ * still work correctly when executed.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The View being executed.
+ *
+ * @return array
+ *   An associative array where each key is a string to be replaced, and the
+ *   corresponding value is its replacement. The strings to replace are often
+ *   surrounded with '***', as illustrated in the example implementation, to
+ *   avoid collisions with other values in the query.
+ */
+function hook_views_query_substitutions(ViewExecutable $view) {
+  // Example from views_views_query_substitutions().
+  return [
+    '***CURRENT_VERSION***' => \Drupal::VERSION,
+    '***CURRENT_TIME***' => REQUEST_TIME,
+    '***LANGUAGE_language_content***' => \Drupal::languageManager()->getCurrentLanguage(LanguageInterface::TYPE_CONTENT)->getId(),
+    PluginBase::VIEWS_QUERY_LANGUAGE_SITE_DEFAULT => \Drupal::languageManager()->getDefaultLanguage()->getId(),
+  ];
+}
+
+/**
+ * Replace special strings when processing a view with form elements.
+ *
+ * @return array
+ *   An associative array where each key is a string to be replaced, and the
+ *   corresponding value is its replacement. The value will be escaped unless it
+ *   is already marked safe.
+ */
+function hook_views_form_substitutions() {
+  return [
+    '<!--views-form-example-substitutions-->' => 'Example Substitution',
+  ];
+}
+
+/**
+ * Alter a view at the very beginning of Views processing.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ * @param string $display_id
+ *   The machine name of the active display.
+ * @param array $args
+ *   An array of arguments passed into the view.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_pre_view(ViewExecutable $view, $display_id, array &$args) {
+
+  // Modify contextual filters for my_special_view if user has 'my special permission'.
+  $account = \Drupal::currentUser();
+
+  if ($view->id() == 'my_special_view' && $account->hasPermission('my special permission') && $display_id == 'public_display') {
+    $args[0] = 'custom value';
+  }
+}
+
+/**
+ * Act on the view before the query is built, but after displays are attached.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_pre_build(ViewExecutable $view) {
+  // Because of some inexplicable business logic, we should remove all
+  // attachments from all views on Mondays.
+  // (This alter could be done later in the execution process as well.)
+  if (date('D') == 'Mon') {
+    unset($view->attachment_before);
+    unset($view->attachment_after);
+  }
+}
+
+/**
+ * Act on the view immediately after the query is built.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_post_build(ViewExecutable $view) {
+  // If the exposed field 'type' is set, hide the column containing the content
+  // type. (Note that this is a solution for a particular view, and makes
+  // assumptions about both exposed filter settings and the fields in the view.
+  // Also note that this alter could be done at any point before the view being
+  // rendered.)
+  if ($view->id() == 'my_view' && isset($view->exposed_raw_input['type']) && $view->exposed_raw_input['type'] != 'All') {
+    // 'Type' should be interpreted as content type.
+    if (isset($view->field['type'])) {
+      $view->field['type']->options['exclude'] = TRUE;
+    }
+  }
+}
+
+/**
+ * Act on the view after the query is built and just before it is executed.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_pre_execute(ViewExecutable $view) {
+  // Whenever a view queries more than two tables, show a message that notifies
+  // view administrators that the query might be heavy.
+  // (This action could be performed later in the execution process, but not
+  // earlier.)
+  $account = \Drupal::currentUser();
+
+  if (count($view->query->tables) > 2 && $account->hasPermission('administer views')) {
+    drupal_set_message(t('The view %view may be heavy to execute.', ['%view' => $view->id()]), 'warning');
+  }
+}
+
+/**
+ * Act on the view immediately after the query has been executed.
+ *
+ * At this point the query has been executed, but the preRender() phase has
+ * not yet happened for handlers.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_post_execute(ViewExecutable $view) {
+  // If there are more than 100 results, show a message that encourages the user
+  // to change the filter settings.
+  // (This action could be performed later in the execution process, but not
+  // earlier.)
+  if ($view->total_rows > 100) {
+    drupal_set_message(t('You have more than 100 hits. Use the filter settings to narrow down your list.'));
+  }
+}
+
+/**
+ * Act on the view immediately before rendering it.
+ *
+ * At this point the query has been executed, and the preRender() phase has
+ * already happened for handlers, so all data should be available. This hook
+ * can be used by themes.
+ *
+ * Output can be added to the view by setting $view->attachment_before
+ * and $view->attachment_after.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_pre_render(ViewExecutable $view) {
+  // Scramble the order of the rows shown on this result page.
+  // Note that this could be done earlier, but not later in the view execution
+  // process.
+  shuffle($view->result);
+}
+
+/**
+ * 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.
+ * This hook can be used by themes.
+ *
+ * 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.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ * @param string $output
+ *   A flat string with the rendered output of the view.
+ * @param \Drupal\views\Plugin\views\cache\CachePluginBase $cache
+ *   The cache settings.
+ *
+ * @see \Drupal\views\ViewExecutable
+ */
+function hook_views_post_render(ViewExecutable $view, &$output, CachePluginBase $cache) {
+  // When using full pager, disable any time-based caching if there are fewer
+  // than 10 results.
+  if ($view->pager instanceof Drupal\views\Plugin\views\pager\Full && $cache instanceof Drupal\views\Plugin\views\cache\Time && count($view->result) < 10) {
+    $cache->options['results_lifespan'] = 0;
+    $cache->options['output_lifespan'] = 0;
+  }
+}
+
+/**
+ * Alter the query before it is executed.
+ *
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object about to be processed.
+ * @param QueryPluginBase $query
+ *   The query plugin object for the query.
+ *
+ * @see hook_views_query_substitutions()
+ * @see \Drupal\views\Plugin\views\query\Sql
+ */
+function hook_views_query_alter(ViewExecutable $view, QueryPluginBase $query) {
+  // (Example assuming a view with an exposed filter on node title.)
+  // If the input for the title filter is a positive integer, filter against
+  // node ID instead of node title.
+  if ($view->id() == 'my_view' && is_numeric($view->exposed_raw_input['title']) && $view->exposed_raw_input['title'] > 0) {
+    // Traverse through the 'where' part of the query.
+    foreach ($query->where as &$condition_group) {
+      foreach ($condition_group['conditions'] as &$condition) {
+        // If this is the part of the query filtering on title, chang the
+        // condition to filter on node ID.
+        if ($condition['field'] == 'node.title') {
+          $condition = [
+            'field' => 'node.nid',
+            'value' => $view->exposed_raw_input['title'],
+            'operator' => '=',
+          ];
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Alter the view preview information.
+ *
+ * The view preview information is optionally displayed when a view is
+ * previewed in the administrative UI. It includes query and performance
+ * statistics.
+ *
+ * @param array $rows
+ *   An associative array with two keys:
+ *   - query: An array of rows suitable for '#type' => 'table', containing
+ *     information about the query and the display title and path.
+ *   - statistics: An array of rows suitable for '#type' => 'table',
+ *     containing performance statistics.
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object.
+ *
+ * @see \Drupal\views_ui\ViewUI
+ * @see table.html.twig
+ */
+function hook_views_preview_info_alter(array &$rows, ViewExecutable $view) {
+  // Adds information about the tables being queried by the view to the query
+  // part of the info box.
+  $rows['query'][] = [
+    t('<strong>Table queue</strong>'),
+    count($view->query->table_queue) . ': (' . implode(', ', array_keys($view->query->table_queue)) . ')',
+  ];
+}
+
+/**
+ * Alter the links displayed at the top of the view edit form.
+ *
+ * @param array $links
+ *   A renderable array of links which will be displayed at the top of the
+ *   view edit form. Each entry will be in a form suitable for
+ *   '#theme' => 'links'.
+ * @param \Drupal\views\ViewExecutable $view
+ *   The view object being edited.
+ * @param string $display_id
+ *   The ID of the display being edited, e.g. 'default' or 'page_1'.
+ *
+ * @see \Drupal\views_ui\ViewUI::renderDisplayTop()
+ */
+function hook_views_ui_display_top_links_alter(array &$links, ViewExecutable $view, $display_id) {
+  // Put the export link first in the list.
+  if (isset($links['export'])) {
+    $links = ['export' => $links['export']] + $links;
+  }
+}
+
+// @todo Describe how to alter a view ajax response with event listeners.
+
+/**
+ * Allow modules to respond to the invalidation of the Views cache.
+ *
+ * This hook will fire whenever a view is enabled, disabled, created,
+ * updated, or deleted.
+ *
+ * @see views_invalidate_cache()
+ */
+function hook_views_invalidate_cache() {
+  \Drupal\Core\Cache\Cache::invalidateTags(['views']);
+}
+
+/**
+ * Modify the list of available views access plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_access_alter(array &$plugins) {
+  // Remove the available plugin because the users should not have access to it.
+  unset($plugins['role']);
+}
+
+/**
+ * Modify the list of available views default argument plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_argument_default_alter(array &$plugins) {
+  // Remove the available plugin because the users should not have access to it.
+  unset($plugins['php']);
+}
+
+/**
+ * Modify the list of available views argument validation plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_argument_validator_alter(array &$plugins) {
+  // Remove the available plugin because the users should not have access to it.
+  unset($plugins['php']);
+}
+
+/**
+ * Modify the list of available views cache plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_cache_alter(array &$plugins) {
+  // Change the title.
+  $plugins['time']['title'] = t('Custom title');
+}
+
+/**
+ * Modify the list of available views display extender plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_display_extenders_alter(array &$plugins) {
+  // Alter the title of an existing plugin.
+  $plugins['time']['title'] = t('Custom title');
+}
+
+/**
+ * Modify the list of available views display plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_display_alter(array &$plugins) {
+  // Alter the title of an existing plugin.
+  $plugins['rest_export']['title'] = t('Export');
+}
+
+/**
+ * Modify the list of available views exposed form plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_exposed_form_alter(array &$plugins) {
+  // Remove the available plugin because the users should not have access to it.
+  unset($plugins['input_required']);
+}
+
+/**
+ * Modify the list of available views join plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_join_alter(array &$plugins) {
+  // Print out all join plugin names for debugging purposes.
+  debug($plugins);
+}
+
+/**
+ * Modify the list of available views pager plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_pager_alter(array &$plugins) {
+  // Remove the sql based plugin to force good performance.
+  unset($plugins['full']);
+}
+
+/**
+ * Modify the list of available views query plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_query_alter(array &$plugins) {
+  // Print out all query plugin names for debugging purposes.
+  debug($plugins);
+}
+
+/**
+ * Modify the list of available views row plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_row_alter(array &$plugins) {
+  // Change the used class of a plugin.
+  $plugins['entity:node']['class'] = 'Drupal\node\Plugin\views\row\NodeRow';
+  $plugins['entity:node']['module'] = 'node';
+}
+
+/**
+ * Modify the list of available views style plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_style_alter(array &$plugins) {
+  // Change the theme hook of a plugin.
+  $plugins['html_list']['theme'] = 'custom_views_view_list';
+}
+
+/**
+ * Modify the list of available views wizard plugins.
+ *
+ * This hook may be used to modify plugin properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing plugin definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsPluginManager
+ */
+function hook_views_plugins_wizard_alter(array &$plugins) {
+  // Change the title of a plugin.
+  $plugins['node_revision']['title'] = t('Node revision wizard');
+}
+
+/**
+ * Modify the list of available views area handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_area_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * Modify the list of available views argument handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_argument_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * Modify the list of available views field handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_field_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * Modify the list of available views filter handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_filter_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * Modify the list of available views relationship handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_relationship_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * Modify the list of available views sort handler plugins.
+ *
+ * This hook may be used to modify handler properties after they have been
+ * specified by other modules.
+ *
+ * @param array $plugins
+ *   An array of all the existing handler definitions, passed by reference.
+ *
+ * @see \Drupal\views\Plugin\ViewsHandlerManager
+ */
+function hook_views_plugins_sort_alter(array &$plugins) {
+  // Change the 'title' handler class.
+  $plugins['title']['class'] = 'Drupal\\example\\ExampleClass';
+}
+
+/**
+ * @} End of "addtogroup hooks".
+ */
+
+/**
+ * @}
+ */