Hooks

Allow modules to interact with the Drupal core.

Drupal's module system is based on the concept of "hooks". A hook is a PHP function that is named foo_bar(), where "foo" is the name of the module (whose filename is thus foo.module) and "bar" is the name of the hook. Each hook has a defined set of parameters and a specified result type.

To extend Drupal, a module need simply implement a hook. When Drupal wishes to allow intervention from modules, it determines which modules implement a hook and calls that hook in all enabled modules that implement it.

The available hooks to implement are explained here in the Hooks section of the developer documentation. The string "hook" is used as a placeholder for the module name in the hook definitions. For example, if the module file is called example.module, then hook_help() as implemented by that module would be defined as example_help().

The example functions included are not part of the Drupal core, they are just models that you can modify. Only the hooks implemented within modules are executed when running Drupal.

End of "defgroup hooks".

See also

Default theme implementations

Callbacks

File

drupal/core/includes/module.inc, line 235
API for loading and interacting with Drupal modules.

Functions

Namesort descending Location Description
hook_admin_paths drupal/core/modules/system/system.api.php Define administrative paths.
hook_admin_paths_alter drupal/core/modules/system/system.api.php Redefine administrative paths defined by other modules.
hook_ajax_render_alter drupal/core/modules/system/system.api.php Alter the commands that are sent to the user through the Ajax framework.
hook_archiver_info_alter drupal/core/modules/system/system.api.php Alter archiver information declared by other modules.
hook_batch_alter drupal/core/modules/system/system.api.php Alter batch information before a batch is processed.
hook_block_access drupal/core/modules/block/block.api.php Control access to a block instance.
hook_block_view_alter drupal/core/modules/block/block.api.php Alter the result of \Drupal\block\BlockBase::build().
hook_block_view_BASE_BLOCK_ID_alter drupal/core/modules/block/block.api.php Provide a block plugin specific block_view alteration.
hook_cache_flush drupal/core/modules/system/system.api.php Flush all persistent and static caches.
hook_ckeditor_css_alter drupal/core/modules/ckeditor/ckeditor.api.php Modify the list of CSS files that will be added to a CKEditor instance.
hook_ckeditor_plugin_info_alter drupal/core/modules/ckeditor/ckeditor.api.php Modify the list of available CKEditor plugins.
hook_comment_create drupal/core/modules/comment/comment.api.php Act on a newly created comment.
hook_comment_delete drupal/core/modules/comment/comment.api.php Respond to comment deletion.
hook_comment_insert drupal/core/modules/comment/comment.api.php Respond to creation of a new comment.
hook_comment_load drupal/core/modules/comment/comment.api.php Act on comments being loaded from the database.
hook_comment_predelete drupal/core/modules/comment/comment.api.php Act before comment deletion.
hook_comment_presave drupal/core/modules/comment/comment.api.php Act on a comment being inserted or updated.
hook_comment_publish drupal/core/modules/comment/comment.api.php Respond to a comment being published by a moderator.
hook_comment_unpublish drupal/core/modules/comment/comment.api.php Respond to a comment being unpublished by a moderator.
hook_comment_update drupal/core/modules/comment/comment.api.php Respond to updates to a comment.
hook_comment_view drupal/core/modules/comment/comment.api.php Act on a comment that is being assembled before rendering.
hook_comment_view_alter drupal/core/modules/comment/comment.api.php Alter the results of comment_view().
hook_contextual_links_view_alter drupal/core/modules/contextual/contextual.api.php Alter a contextual links element before it is rendered.
hook_countries_alter drupal/core/modules/system/system.api.php Alter the default country list.
hook_cron drupal/core/modules/system/system.api.php Perform periodic actions.
hook_css_alter drupal/core/modules/system/system.api.php Alter CSS files before they are output on the page.
hook_custom_theme drupal/core/modules/system/system.api.php Return the machine-readable name of the theme to use for the current page.
hook_data_type_info drupal/core/modules/system/system.api.php Defines available data types for the typed data API.
hook_data_type_info_alter drupal/core/modules/system/system.api.php Alter available data types for typed data wrappers.
hook_delete drupal/core/modules/node/node.api.php Respond to node deletion.
hook_disable drupal/core/modules/system/system.api.php Perform necessary actions before module is disabled.
hook_drupal_goto_alter drupal/core/modules/system/system.api.php Change the page the user is sent to by drupal_goto().
hook_editor_default_settings drupal/core/modules/editor/editor.api.php Provides defaults for editor instances.
hook_editor_default_settings_alter drupal/core/modules/editor/editor.api.php Modifies default settings for editor instances.
hook_editor_info_alter drupal/core/modules/editor/editor.api.php Performs alterations on text editor definitions.
hook_editor_js_settings_alter drupal/core/modules/editor/editor.api.php Modifies JavaScript settings that are added for text editors.
hook_edit_editor_alter drupal/core/modules/edit/edit.api.php Allow modules to alter in-place editor plugin metadata.
hook_element_info drupal/core/modules/system/system.api.php Allows modules to declare their own Form API element types and specify their default values.
hook_element_info_alter drupal/core/modules/system/system.api.php Alter the element type information returned from modules.
hook_enable drupal/core/modules/system/system.api.php Perform necessary actions after module is enabled.
hook_entity_bundle_create drupal/core/includes/entity.api.php Act on entity_bundle_create().
hook_entity_bundle_delete drupal/core/includes/entity.api.php Act on entity_bundle_delete().
hook_entity_bundle_info drupal/core/includes/entity.api.php Describe the bundles for entity types.
hook_entity_bundle_info_alter drupal/core/includes/entity.api.php Alter the bundles for entity types.
hook_entity_bundle_rename drupal/core/includes/entity.api.php Act on entity_bundle_rename().
hook_entity_create drupal/core/includes/entity.api.php Act on a newly created entity.
hook_entity_delete drupal/core/includes/entity.api.php Respond to entity deletion.
hook_entity_display_alter drupal/core/includes/entity.api.php Alters the settings used for displaying an entity.
hook_entity_field_access drupal/core/includes/entity.api.php Control access to fields.
hook_entity_field_access_alter drupal/core/includes/entity.api.php Alters the default access behaviour for a given field.
hook_entity_field_info drupal/core/includes/entity.api.php Define custom entity properties.
hook_entity_field_info_alter drupal/core/includes/entity.api.php Alter defined entity properties.
hook_entity_form_display_alter drupal/core/includes/entity.api.php Alters the settings used for displaying an entity form.
hook_entity_info drupal/core/includes/entity.api.php Add to entity type definitions.
hook_entity_info_alter drupal/core/includes/entity.api.php Alter the entity type definitions.
hook_entity_insert drupal/core/includes/entity.api.php Act on entities when inserted.
hook_entity_load drupal/core/includes/entity.api.php Act on entities when loaded.
hook_entity_operation_alter drupal/core/includes/entity.api.php Alter entity operations.
hook_entity_predelete drupal/core/includes/entity.api.php Act before entity deletion.
hook_entity_prepare_view drupal/core/includes/entity.api.php Act on entities as they are being prepared for view.
hook_entity_presave drupal/core/includes/entity.api.php Act on an entity before it is about to be created or updated.
hook_entity_query_alter drupal/core/includes/entity.api.php Alter or execute an Drupal\Core\Entity\Query\EntityQueryInterface.
hook_entity_update drupal/core/includes/entity.api.php Act on entities when updated.
hook_entity_view drupal/core/includes/entity.api.php Act on entities being assembled before rendering.
hook_entity_view_alter drupal/core/includes/entity.api.php Alter the results of ENTITY_view().
hook_entity_view_mode_alter drupal/core/includes/entity.api.php Change the view mode of an entity that is being displayed.
hook_entity_view_mode_info_alter drupal/core/includes/entity.api.php Alter the view modes for entity types.
hook_field_access drupal/core/modules/field/field.api.php Determine whether the user has access to a given field.
hook_field_attach_delete drupal/core/modules/field/field.api.php Act on field_attach_delete().
hook_field_attach_delete_revision drupal/core/modules/field/field.api.php Act on field_attach_delete_revision().
hook_field_attach_extract_form_values drupal/core/modules/field/field.api.php Act on field_attach_extract_form_values().
hook_field_attach_form drupal/core/modules/field/field.api.php Act on field_attach_form().
hook_field_attach_insert drupal/core/modules/field/field.api.php Act on field_attach_insert().
hook_field_attach_load drupal/core/modules/field/field.api.php Act on field_attach_load().
hook_field_attach_prepare_translation_alter drupal/core/modules/field/field.api.php Perform alterations on field_attach_prepare_translation().
hook_field_attach_preprocess_alter drupal/core/modules/field/field.api.php Alter field_attach_preprocess() variables.
hook_field_attach_presave drupal/core/modules/field/field.api.php Act on field_attach_presave().
hook_field_attach_purge drupal/core/modules/field/field.api.php Act on field_purge_data().
hook_field_attach_update drupal/core/modules/field/field.api.php Act on field_attach_update().
hook_field_attach_validate drupal/core/modules/field/field.api.php Act on field_attach_validate().
hook_field_attach_view_alter drupal/core/modules/field/field.api.php Perform alterations on field_attach_view() or field_view_field().
hook_field_available_languages_alter drupal/core/modules/field/field.api.php Alter field_available_languages() values.
hook_field_create_field drupal/core/modules/field/field.api.php Act on a field being created.
hook_field_create_instance drupal/core/modules/field/field.api.php Act on a field instance being created.
hook_field_delete drupal/core/modules/field/field.api.php Define custom delete behavior for this module's field data.
hook_field_delete_field drupal/core/modules/field/field.api.php Act on a field being deleted.
hook_field_delete_instance drupal/core/modules/field/field.api.php Act on a field instance being deleted.
hook_field_delete_revision drupal/core/modules/field/field.api.php Define custom revision delete behavior for this module's field types.
hook_field_extra_fields drupal/core/modules/field/field.api.php Exposes "pseudo-field" components on fieldable entities.
hook_field_extra_fields_alter drupal/core/modules/field/field.api.php Alter "pseudo-field" components on fieldable entities.
hook_field_formatter_info_alter drupal/core/modules/field/field.api.php Perform alterations on Field API formatter types.
hook_field_info drupal/core/modules/field/field.api.php Define Field API field types.
hook_field_info_alter drupal/core/modules/field/field.api.php Perform alterations on Field API field types.
hook_field_info_max_weight drupal/core/modules/field/field.api.php Returns the maximum weight for the entity components handled by the module.
hook_field_insert drupal/core/modules/field/field.api.php Define custom insert behavior for this module's field data.
hook_field_is_empty drupal/core/modules/field/field.api.php Define what constitutes an empty item for a field type.
hook_field_language_alter drupal/core/modules/field/field.api.php Perform alterations on field_language() values.
hook_field_load drupal/core/modules/field/field.api.php Define custom load behavior for this module's field types.
hook_field_prepare_translation drupal/core/modules/field/field.api.php Define custom prepare_translation behavior for this module's field types.
hook_field_prepare_view drupal/core/modules/field/field.api.php Prepare field values prior to display.
hook_field_presave drupal/core/modules/field/field.api.php Define custom presave behavior for this module's field types.
hook_field_purge_field drupal/core/modules/field/field.api.php Acts when a field record is being purged.
hook_field_purge_instance drupal/core/modules/field/field.api.php Acts when a field instance is being purged.
hook_field_read_field drupal/core/modules/field/field.api.php Act on field records being read from the database.
hook_field_read_instance drupal/core/modules/field/field.api.php Act on a field record being read from the database.
hook_field_schema drupal/core/modules/field/field.api.php Define the Field API schema for a field structure.
hook_field_storage_create_field drupal/core/modules/field/field.api.php Act on creation of a new field.
hook_field_storage_delete drupal/core/modules/field/field.api.php Delete all field data for an entity.
hook_field_storage_delete_field drupal/core/modules/field/field.api.php Act on deletion of a field.
hook_field_storage_delete_instance drupal/core/modules/field/field.api.php Act on deletion of a field instance.
hook_field_storage_delete_revision drupal/core/modules/field/field.api.php Delete a single revision of field data for an entity.
hook_field_storage_details drupal/core/modules/field/field.api.php Reveal the internal details about the storage for a field.
hook_field_storage_details_alter drupal/core/modules/field/field.api.php Perform alterations on Field API storage details.
hook_field_storage_info drupal/core/modules/field/field.api.php Expose Field API storage backends.
hook_field_storage_info_alter drupal/core/modules/field/field.api.php Perform alterations on Field API storage types.
hook_field_storage_load drupal/core/modules/field/field.api.php Load field data for a set of entities.
hook_field_storage_pre_insert drupal/core/modules/field/field.api.php Act before the storage backends insert field data.
hook_field_storage_pre_load drupal/core/modules/field/field.api.php Act before the storage backends load field data.
hook_field_storage_pre_update drupal/core/modules/field/field.api.php Act before the storage backends update field data.
hook_field_storage_purge drupal/core/modules/field/field.api.php Remove field storage information when field data is purged.
hook_field_storage_purge_field drupal/core/modules/field/field.api.php Remove field storage information when a field record is purged.
hook_field_storage_purge_field_instance drupal/core/modules/field/field.api.php Remove field storage information when a field instance is purged.
hook_field_storage_query drupal/core/modules/field/field.api.php Execute a Drupal\Core\Entity\EntityFieldQuery.
hook_field_storage_update_field drupal/core/modules/field/field.api.php Update the storage information for a field.
hook_field_storage_write drupal/core/modules/field/field.api.php Write field data for an entity.
hook_field_update drupal/core/modules/field/field.api.php Define custom update behavior for this module's field data.
hook_field_update_field drupal/core/modules/field/field.api.php Act on a field being updated.
hook_field_update_forbid drupal/core/modules/field/field.api.php Forbid a field update from occurring.
hook_field_update_instance drupal/core/modules/field/field.api.php Act on a field instance being updated.
hook_field_validate drupal/core/modules/field/field.api.php Validate this module's field data.
hook_field_widget_form_alter drupal/core/modules/field/field.api.php Alter forms for field widgets provided by other modules.
hook_field_widget_info_alter drupal/core/modules/field/field.api.php Perform alterations on Field API widget types.
hook_field_widget_WIDGET_TYPE_form_alter drupal/core/modules/field/field.api.php Alter widget forms for a specific widget provided by another module.
hook_filetransfer_info drupal/core/modules/system/system.api.php Register information about FileTransfer classes provided by a module.
hook_filetransfer_info_alter drupal/core/modules/system/system.api.php Alter the FileTransfer class registry.
hook_file_download drupal/core/modules/system/system.api.php Control access to private file downloads and specify HTTP headers.
hook_file_mimetype_mapping_alter drupal/core/modules/system/system.api.php Alter MIME type mappings used to determine MIME type from a file extension.
hook_file_url_alter drupal/core/modules/system/system.api.php Alter the URL to a file.
hook_filter_format_disable drupal/core/modules/filter/filter.api.php Perform actions when a text format has been disabled.
hook_filter_info_alter drupal/core/modules/filter/filter.api.php Perform alterations on filter definitions.
hook_form drupal/core/modules/node/node.api.php Display a node editing form.
hook_forms drupal/core/modules/system/system.api.php Map form_ids to form builder functions.
hook_form_alter drupal/core/modules/system/system.api.php Perform alterations before a form is rendered.
hook_form_BASE_FORM_ID_alter drupal/core/modules/system/system.api.php Provide a form-specific alteration for shared ('base') forms.
hook_form_FORM_ID_alter drupal/core/modules/system/system.api.php Provide a form-specific alteration instead of the global hook_form_alter().
hook_help drupal/core/modules/help/help.api.php Provide online user help.
hook_hook_info drupal/core/modules/system/system.api.php Defines one or more hooks that are exposed by a module.
hook_html_head_alter drupal/core/modules/system/system.api.php Alter XHTML HEAD tags before they are rendered by drupal_get_html_head().
hook_image_effect_info drupal/core/modules/image/image.api.php Define information about image effects provided by a module.
hook_image_effect_info_alter drupal/core/modules/image/image.api.php Alter the information provided in hook_image_effect_info().
hook_image_style_flush drupal/core/modules/image/image.api.php Respond to image style flushing.
hook_insert drupal/core/modules/node/node.api.php Respond to creation of a new node.
hook_install drupal/core/modules/system/system.api.php Perform setup tasks when the module is installed.
hook_install_tasks drupal/core/modules/system/system.api.php Return an array of tasks to be performed by an installation profile.
hook_install_tasks_alter drupal/core/modules/system/system.api.php Alter the full list of installation tasks.
hook_js_alter drupal/core/modules/system/system.api.php Perform necessary alterations to the JavaScript before it is presented on the page.
hook_language_delete drupal/core/modules/language/language.api.php Allow modules to react before the deletion of a language.
hook_language_fallback_candidates_alter drupal/core/modules/system/language.api.php Perform alterations on the language fallback candidates.
hook_language_insert drupal/core/modules/language/language.api.php React to a language that was just added to the system.
hook_language_negotiation_info drupal/core/modules/system/language.api.php Define language negotiation methods.
hook_language_negotiation_info_alter drupal/core/modules/system/language.api.php Perform alterations on language negotiation methods.
hook_language_presave drupal/core/modules/language/language.api.php React to a language about to be added or updated in the system.
hook_language_switch_links_alter drupal/core/modules/system/language.api.php Perform alterations on language switcher links.
hook_language_types_info drupal/core/modules/system/language.api.php Define language types.
hook_language_types_info_alter drupal/core/modules/system/language.api.php Perform alterations on language types.
hook_language_update drupal/core/modules/language/language.api.php React to a language that was just updated in the system.
hook_library_info drupal/core/modules/system/system.api.php Registers JavaScript/CSS libraries associated with a module.
hook_library_info_alter drupal/core/modules/system/system.api.php Alters the JavaScript/CSS library registry.
hook_load drupal/core/modules/node/node.api.php Act on nodes being loaded from the database.
hook_locale_translation_projects_alter drupal/core/modules/locale/locale.api.php Alter the list of projects to be updated by locale's interface translation.
hook_local_actions drupal/core/modules/system/system.api.php Define route-based local actions.
hook_mail drupal/core/modules/system/system.api.php Prepare a message based on parameters; called from drupal_mail().
hook_mail_alter drupal/core/modules/system/system.api.php Alter an email message created with the drupal_mail() function.
hook_menu drupal/core/modules/system/system.api.php Define menu items and page callbacks.
hook_menu_alter drupal/core/modules/system/system.api.php Alter the data being saved to the {menu_router} table after hook_menu is invoked.
hook_menu_breadcrumb_alter drupal/core/modules/system/system.api.php Alter links in the active trail before it is rendered as the breadcrumb.
hook_menu_contextual_links_alter drupal/core/modules/system/system.api.php Alter contextual links before they are rendered.
hook_menu_delete drupal/core/modules/menu/menu.api.php Respond to a custom menu deletion.
hook_menu_get_item_alter drupal/core/modules/system/system.api.php Alter a menu router item right after it has been retrieved from the database or cache.
hook_menu_insert drupal/core/modules/menu/menu.api.php Respond to a custom menu creation.
hook_menu_link_delete drupal/core/modules/menu_link/menu_link.api.php Inform modules that a menu link has been deleted.
hook_menu_link_insert drupal/core/modules/menu_link/menu_link.api.php Inform modules that a menu link has been created.
hook_menu_link_load drupal/core/modules/menu_link/menu_link.api.php Alter menu links when loaded and before they are rendered.
hook_menu_link_presave drupal/core/modules/menu_link/menu_link.api.php Alter the data of a menu link entity before it is created or updated.
hook_menu_link_update drupal/core/modules/menu_link/menu_link.api.php Inform modules that a menu link has been updated.
hook_menu_local_tasks drupal/core/modules/system/system.api.php Alter tabs and actions displayed on the page before they are rendered.
hook_menu_local_tasks_alter drupal/core/modules/system/system.api.php Alter tabs and actions displayed on the page before they are rendered.
hook_menu_update drupal/core/modules/menu/menu.api.php Respond to a custom menu update.
hook_modules_disabled drupal/core/modules/system/system.api.php Perform necessary actions after modules are disabled.
hook_modules_enabled drupal/core/modules/system/system.api.php Perform necessary actions after modules are enabled.
hook_modules_installed drupal/core/modules/system/system.api.php Perform necessary actions after modules are installed.
hook_modules_preenable drupal/core/modules/system/system.api.php Perform necessary actions before modules are enabled.
hook_modules_preinstall drupal/core/modules/system/system.api.php Perform necessary actions before modules are installed.
hook_modules_uninstalled drupal/core/modules/system/system.api.php Perform necessary actions after modules are uninstalled.
hook_module_implements_alter drupal/core/modules/system/system.api.php Alter the registry of modules implementing a hook.
hook_node_access drupal/core/modules/node/node.api.php Controls access to a node.
hook_node_access_records drupal/core/modules/node/node.api.php Set permissions for a node to be written to the database.
hook_node_access_records_alter drupal/core/modules/node/node.api.php Alter permissions for a node before it is written to the database.
hook_node_create drupal/core/modules/node/node.api.php Act on a newly created node.
hook_node_delete drupal/core/modules/node/node.api.php Respond to node deletion.
hook_node_grants drupal/core/modules/node/node.api.php Inform the node access system what permissions the user has.
hook_node_grants_alter drupal/core/modules/node/node.api.php Alter user access rules when trying to view, edit or delete a node.
hook_node_info drupal/core/modules/node/node.api.php Define module-provided node types.
hook_node_insert drupal/core/modules/node/node.api.php Respond to creation of a new node.
hook_node_load drupal/core/modules/node/node.api.php Act on arbitrary nodes being loaded from the database.
hook_node_predelete drupal/core/modules/node/node.api.php Act before node deletion.
hook_node_prepare drupal/core/modules/node/node.api.php Act on a node object about to be shown on the add/edit form.
hook_node_presave drupal/core/modules/node/node.api.php Act on a node being inserted or updated.
hook_node_revision_delete drupal/core/modules/node/node.api.php Respond to deletion of a node revision.
hook_node_search_result drupal/core/modules/node/node.api.php Act on a node being displayed as a search result.
hook_node_submit drupal/core/modules/node/node.api.php Act on a node after validated form values have been copied to it.
hook_node_type_delete drupal/core/modules/node/node.api.php Respond to node type deletion.
hook_node_type_insert drupal/core/modules/node/node.api.php Respond to node type creation.
hook_node_type_update drupal/core/modules/node/node.api.php Respond to node type updates.
hook_node_update drupal/core/modules/node/node.api.php Respond to updates to a node.
hook_node_update_index drupal/core/modules/node/node.api.php Act on a node being indexed for searching.
hook_node_validate drupal/core/modules/node/node.api.php Perform node validation before a node is created or updated.
hook_node_view drupal/core/modules/node/node.api.php Act on a node that is being assembled before rendering.
hook_node_view_alter drupal/core/modules/node/node.api.php Alter the results of node_view().
hook_overlay_child_initialize drupal/core/modules/overlay/overlay.api.php Allow modules to act when an overlay child window is initialized.
hook_overlay_parent_initialize drupal/core/modules/overlay/overlay.api.php Allow modules to act when an overlay parent window is initialized.
hook_page_alter drupal/core/modules/system/system.api.php Perform alterations before a page is rendered.
hook_page_build drupal/core/modules/system/system.api.php Add elements to a page before it is rendered.
hook_path_delete drupal/core/modules/path/path.api.php Respond to a path being deleted.
hook_path_insert drupal/core/modules/path/path.api.php Respond to a path being inserted.
hook_path_update drupal/core/modules/path/path.api.php Respond to a path being updated.
hook_permission drupal/core/modules/system/system.api.php Define user permissions.
hook_prepare drupal/core/modules/node/node.api.php Act on a node object about to be shown on the add/edit form.
hook_query_alter drupal/core/modules/system/system.api.php Perform alterations to a structured query.
hook_query_TAG_alter drupal/core/modules/system/system.api.php Perform alterations to a structured query for a given tag.
hook_queue_info drupal/core/modules/system/system.api.php Declare queues holding items that need to be run periodically.
hook_queue_info_alter drupal/core/modules/system/system.api.php Alter cron queue information before cron runs.
hook_ranking drupal/core/modules/node/node.api.php Provide additional methods of scoring for core search results for nodes.
hook_rdf_mapping drupal/core/modules/rdf/rdf.api.php Allow modules to define RDF mappings for field bundles.
hook_rdf_namespaces drupal/core/modules/rdf/rdf.api.php Allow modules to define namespaces for RDF mappings.
hook_rebuild drupal/core/modules/system/system.api.php Rebuild data based upon refreshed caches.
hook_requirements drupal/core/modules/system/system.api.php Check installation requirements and do status reporting.
hook_rest_resource_alter drupal/core/modules/rest/rest.api.php Alter the resource plugin definitions.
hook_schema drupal/core/modules/system/system.api.php Define the current version of the database schema.
hook_schema_alter drupal/core/modules/system/system.api.php Perform alterations to existing database schemas.
hook_search_access drupal/core/modules/search/search.api.php Define access to a custom search routine.
hook_search_admin drupal/core/modules/search/search.api.php Add elements to the search settings form.
hook_search_execute drupal/core/modules/search/search.api.php Execute a search for a set of key words.
hook_search_info drupal/core/modules/search/search.api.php Define a custom search type.
hook_search_page drupal/core/modules/search/search.api.php Override the rendering of search results.
hook_search_preprocess drupal/core/modules/search/search.api.php Preprocess text for search.
hook_search_reset drupal/core/modules/search/search.api.php Take action when the search index is going to be rebuilt.
hook_search_status drupal/core/modules/search/search.api.php Report the status of indexing.
hook_shortcut_default_set drupal/core/modules/shortcut/shortcut.api.php Return the name of a default shortcut set for the provided user account.
hook_simpletest_alter drupal/core/modules/simpletest/simpletest.api.php Alter the list of tests.
hook_stream_wrappers drupal/core/modules/system/system.api.php Registers PHP stream wrapper implementations associated with a module.
hook_stream_wrappers_alter drupal/core/modules/system/system.api.php Alters the list of PHP stream wrapper implementations.
hook_system_info_alter drupal/core/modules/system/system.api.php Alter the information parsed from module and theme .info.yml files
hook_system_themes_page_alter drupal/core/modules/system/system.api.php Alters theme operation links.
hook_system_theme_info drupal/core/modules/system/system.api.php Return additional themes provided by modules.
hook_taxonomy_term_create drupal/core/modules/taxonomy/taxonomy.api.php Act on a newly created term.
hook_taxonomy_term_delete drupal/core/modules/taxonomy/taxonomy.api.php Respond to taxonomy term deletion.
hook_taxonomy_term_insert drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when inserted.
hook_taxonomy_term_load drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when loaded.
hook_taxonomy_term_predelete drupal/core/modules/taxonomy/taxonomy.api.php Act before taxonomy term deletion.
hook_taxonomy_term_presave drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy terms before they are saved.
hook_taxonomy_term_update drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when updated.
hook_taxonomy_term_view drupal/core/modules/taxonomy/taxonomy.api.php Act on a taxonomy term that is being assembled before rendering.
hook_taxonomy_term_view_alter drupal/core/modules/taxonomy/taxonomy.api.php Alter the results of taxonomy_term_view().
hook_taxonomy_vocabulary_create drupal/core/modules/taxonomy/taxonomy.api.php Act on a newly created vocabulary.
hook_taxonomy_vocabulary_delete drupal/core/modules/taxonomy/taxonomy.api.php Respond to taxonomy vocabulary deletion.
hook_taxonomy_vocabulary_insert drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when inserted.
hook_taxonomy_vocabulary_load drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when loaded.
hook_taxonomy_vocabulary_predelete drupal/core/modules/taxonomy/taxonomy.api.php Act before taxonomy vocabulary deletion.
hook_taxonomy_vocabulary_presave drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies before they are saved.
hook_taxonomy_vocabulary_update drupal/core/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when updated.
hook_template_preprocess_default_variables_alter drupal/core/modules/system/system.api.php Alter the default, hook-independent variables for all templates.
hook_test_finished drupal/core/modules/simpletest/simpletest.api.php An individual test has finished.
hook_test_group_finished drupal/core/modules/simpletest/simpletest.api.php A test group has finished.
hook_test_group_started drupal/core/modules/simpletest/simpletest.api.php A test group has started.
hook_theme drupal/core/modules/system/system.api.php Register a module (or theme's) theme implementations.
hook_theme_registry_alter drupal/core/modules/system/system.api.php Alter the theme registry information returned from hook_theme().
hook_tokens drupal/core/modules/system/system.api.php Provide replacement values for placeholder tokens.
hook_tokens_alter drupal/core/modules/system/system.api.php Alter replacement values for placeholder tokens.
hook_token_info drupal/core/modules/system/system.api.php Provide information about available placeholder tokens and token types.
hook_token_info_alter drupal/core/modules/system/system.api.php Alter the metadata about available placeholder tokens and token types.
hook_toolbar drupal/core/modules/toolbar/toolbar.api.php Add items to the toolbar menu.
hook_toolbar_alter drupal/core/modules/toolbar/toolbar.api.php Alter the toolbar menu after hook_toolbar() is invoked.
hook_transliteration_overrides_alter drupal/core/modules/system/language.api.php Provide language-specific overrides for transliteration.
hook_uninstall drupal/core/modules/system/system.api.php Remove any information that the module sets.
hook_update drupal/core/modules/node/node.api.php Respond to updates to a node.
hook_updater_info drupal/core/modules/system/system.api.php Provide information on Updaters (classes that can update Drupal).
hook_updater_info_alter drupal/core/modules/system/system.api.php Alter the Updater information array.
hook_update_dependencies drupal/core/modules/system/system.api.php Return an array of information about module update dependencies.
hook_update_index drupal/core/modules/search/search.api.php Update the search index for this module.
hook_update_last_removed drupal/core/modules/system/system.api.php Return a number which is no longer available as hook_update_N().
hook_update_N drupal/core/modules/system/system.api.php Perform a single update.
hook_update_projects_alter drupal/core/modules/update/update.api.php Alter the list of projects before fetching data and comparing versions.
hook_update_status_alter drupal/core/modules/update/update.api.php Alter the information about available updates for projects.
hook_url_outbound_alter drupal/core/modules/system/system.api.php Alters outbound URLs.
hook_user_cancel drupal/core/modules/user/user.api.php Act on user account cancellations.
hook_user_cancel_methods_alter drupal/core/modules/user/user.api.php Modify account cancellation methods.
hook_user_create drupal/core/modules/user/user.api.php Act on a newly created user.
hook_user_delete drupal/core/modules/user/user.api.php Respond to user deletion.
hook_user_format_name_alter drupal/core/modules/user/user.api.php Alter the username that is displayed for a user.
hook_user_insert drupal/core/modules/user/user.api.php Respond to creation of a new user account.
hook_user_load drupal/core/modules/user/user.api.php Act on user objects when loaded from the database.
hook_user_login drupal/core/modules/user/user.api.php The user just logged in.
hook_user_logout drupal/core/modules/user/user.api.php The user just logged out.
hook_user_predelete drupal/core/modules/user/user.api.php Act before user deletion.
hook_user_presave drupal/core/modules/user/user.api.php Act on a user account being inserted or updated.
hook_user_role_delete drupal/core/modules/user/user.api.php Inform other modules that a user role has been deleted.
hook_user_role_insert drupal/core/modules/user/user.api.php Inform other modules that a user role has been added.
hook_user_role_presave drupal/core/modules/user/user.api.php Inform other modules that a user role is about to be saved.
hook_user_role_update drupal/core/modules/user/user.api.php Inform other modules that a user role has been updated.
hook_user_update drupal/core/modules/user/user.api.php Respond to updates to a user account.
hook_user_view drupal/core/modules/user/user.api.php The user's account information is being displayed.
hook_user_view_alter drupal/core/modules/user/user.api.php The user was built; the module may modify the structured content.
hook_validate drupal/core/modules/node/node.api.php Perform node validation before a node is created or updated.
hook_verify_update_archive drupal/core/modules/update/update.api.php Verify an archive after it has been downloaded and extracted.
hook_view drupal/core/modules/node/node.api.php Display a node.
hook_watchdog drupal/core/modules/system/system.api.php Log an event message.

Sub-Topics

Namesort descending Location Description
Field Formatter API drupal/core/modules/field/field.api.php Define Field API formatter types.
Field Types API drupal/core/modules/field/field.api.php Defines field, widget, display formatter, and storage types.
Field Widget API drupal/core/modules/field/field.api.php Define Field API widget types.