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.

See also

Default theme implementations

Callbacks

File

drupal/includes/module.inc, line 609
API for loading and interacting with Drupal modules.

Functions

Namesort descending Location Description
hook_actions_delete drupal/modules/system/system.api.php Executes code after an action is deleted.
hook_action_info drupal/modules/system/system.api.php Declares information about actions.
hook_action_info_alter drupal/modules/system/system.api.php Alters the actions declared by another module.
hook_admin_paths drupal/modules/system/system.api.php Define administrative paths.
hook_admin_paths_alter drupal/modules/system/system.api.php Redefine administrative paths defined by other modules.
hook_aggregator_fetch drupal/modules/aggregator/aggregator.api.php Create an alternative fetcher for aggregator.module.
hook_aggregator_fetch_info drupal/modules/aggregator/aggregator.api.php Specify the title and short description of your fetcher.
hook_aggregator_parse drupal/modules/aggregator/aggregator.api.php Create an alternative parser for aggregator module.
hook_aggregator_parse_info drupal/modules/aggregator/aggregator.api.php Specify the title and short description of your parser.
hook_aggregator_process drupal/modules/aggregator/aggregator.api.php Create a processor for aggregator.module.
hook_aggregator_process_info drupal/modules/aggregator/aggregator.api.php Specify the title and short description of your processor.
hook_aggregator_remove drupal/modules/aggregator/aggregator.api.php Remove stored feed data.
hook_ajax_render_alter drupal/modules/system/system.api.php Alter the commands that are sent to the user through the Ajax framework.
hook_archiver_info drupal/modules/system/system.api.php Declare archivers to the system.
hook_archiver_info_alter drupal/modules/system/system.api.php Alter archiver information declared by other modules.
hook_batch_alter drupal/modules/system/system.api.php Alter batch information before a batch is processed.
hook_block_cid_parts_alter drupal/modules/block/block.api.php Act on block cache ID (cid) parts before the cid is generated.
hook_block_configure drupal/modules/block/block.api.php Define a configuration form for a block.
hook_block_info drupal/modules/block/block.api.php Define all blocks provided by the module.
hook_block_info_alter drupal/modules/block/block.api.php Change block definition before saving to the database.
hook_block_list_alter drupal/modules/block/block.api.php Act on blocks prior to rendering.
hook_block_save drupal/modules/block/block.api.php Save the configuration options from hook_block_configure().
hook_block_view drupal/modules/block/block.api.php Return a rendered or renderable view of a block.
hook_block_view_alter drupal/modules/block/block.api.php Perform alterations to the content of a block.
hook_block_view_MODULE_DELTA_alter drupal/modules/block/block.api.php Perform alterations to a specific block.
hook_boot drupal/modules/system/system.api.php Perform setup tasks for all page requests.
hook_comment_delete drupal/modules/comment/comment.api.php The comment is being deleted by the moderator.
hook_comment_insert drupal/modules/comment/comment.api.php The comment is being inserted.
hook_comment_load drupal/modules/comment/comment.api.php Comments are being loaded from the database.
hook_comment_presave drupal/modules/comment/comment.api.php The comment passed validation and is about to be saved.
hook_comment_publish drupal/modules/comment/comment.api.php The comment is being published by the moderator.
hook_comment_unpublish drupal/modules/comment/comment.api.php The comment is being unpublished by the moderator.
hook_comment_update drupal/modules/comment/comment.api.php The comment is being updated.
hook_comment_view drupal/modules/comment/comment.api.php The comment is being viewed. This hook can be used to add additional data to the comment before theming.
hook_comment_view_alter drupal/modules/comment/comment.api.php The comment was built; the module may modify the structured content.
hook_contextual_links_view_alter drupal/modules/contextual/contextual.api.php Alter a contextual links element before it is rendered.
hook_countries_alter drupal/modules/system/system.api.php Alter the default country list.
hook_cron drupal/modules/system/system.api.php Perform periodic actions.
hook_cron_queue_info drupal/modules/system/system.api.php Declare queues holding items that need to be run periodically.
hook_cron_queue_info_alter drupal/modules/system/system.api.php Alter cron queue information before cron runs.
hook_css_alter drupal/modules/system/system.api.php Alter CSS files before they are output on the page.
hook_custom_theme drupal/modules/system/system.api.php Return the machine-readable name of the theme to use for the current page.
hook_dashboard_regions drupal/modules/dashboard/dashboard.api.php Add regions to the dashboard.
hook_dashboard_regions_alter drupal/modules/dashboard/dashboard.api.php Alter dashboard regions provided by modules.
hook_date_formats drupal/modules/system/system.api.php Define additional date formats.
hook_date_formats_alter drupal/modules/system/system.api.php Alter date formats declared by another module.
hook_date_format_types drupal/modules/system/system.api.php Define additional date types.
hook_date_format_types_alter drupal/modules/system/system.api.php Modify existing date types.
hook_delete drupal/modules/node/node.api.php Respond to node deletion.
hook_disable drupal/modules/system/system.api.php Perform necessary actions before module is disabled.
hook_drupal_goto_alter drupal/modules/system/system.api.php Change the page the user is sent to by drupal_goto().
hook_element_info drupal/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/modules/system/system.api.php Alter the element type information returned from modules.
hook_enable drupal/modules/system/system.api.php Perform necessary actions after module is enabled.
hook_entity_delete drupal/modules/system/system.api.php Act on entities when deleted.
hook_entity_info drupal/modules/system/system.api.php Inform the base system and the Field API about one or more entity types.
hook_entity_info_alter drupal/modules/system/system.api.php Alter the entity info.
hook_entity_insert drupal/modules/system/system.api.php Act on entities when inserted.
hook_entity_load drupal/modules/system/system.api.php Act on entities when loaded.
hook_entity_prepare_view drupal/modules/system/system.api.php Act on entities as they are being prepared for view.
hook_entity_presave drupal/modules/system/system.api.php Act on an entity before it is about to be created or updated.
hook_entity_query_alter drupal/modules/system/system.api.php Alter or execute an EntityFieldQuery.
hook_entity_update drupal/modules/system/system.api.php Act on entities when updated.
hook_entity_view drupal/modules/system/system.api.php Act on entities being assembled before rendering.
hook_entity_view_alter drupal/modules/system/system.api.php Alter the results of ENTITY_view().
hook_entity_view_mode_alter drupal/modules/system/system.api.php Change the view mode of an entity that is being displayed.
hook_exit drupal/modules/system/system.api.php Perform cleanup tasks.
hook_field_access drupal/modules/field/field.api.php Determine whether the user has access to a given field.
hook_field_attach_create_bundle drupal/modules/field/field.api.php Act on field_attach_create_bundle().
hook_field_attach_delete drupal/modules/field/field.api.php Act on field_attach_delete().
hook_field_attach_delete_bundle drupal/modules/field/field.api.php Act on field_attach_delete_bundle.
hook_field_attach_delete_revision drupal/modules/field/field.api.php Act on field_attach_delete_revision().
hook_field_attach_form drupal/modules/field/field.api.php Act on field_attach_form().
hook_field_attach_insert drupal/modules/field/field.api.php Act on field_attach_insert().
hook_field_attach_load drupal/modules/field/field.api.php Act on field_attach_load().
hook_field_attach_prepare_translation_alter drupal/modules/field/field.api.php Perform alterations on field_attach_prepare_translation().
hook_field_attach_preprocess_alter drupal/modules/field/field.api.php Alter field_attach_preprocess() variables.
hook_field_attach_presave drupal/modules/field/field.api.php Act on field_attach_presave().
hook_field_attach_purge drupal/modules/field/field.api.php Act on field_purge_data().
hook_field_attach_rename_bundle drupal/modules/field/field.api.php Act on field_attach_rename_bundle().
hook_field_attach_submit drupal/modules/field/field.api.php Act on field_attach_submit().
hook_field_attach_update drupal/modules/field/field.api.php Act on field_attach_update().
hook_field_attach_validate drupal/modules/field/field.api.php Act on field_attach_validate().
hook_field_attach_view_alter drupal/modules/field/field.api.php Perform alterations on field_attach_view() or field_view_field().
hook_field_available_languages_alter drupal/modules/field/field.api.php Alter field_available_languages() values.
hook_field_create_field drupal/modules/field/field.api.php Act on a field being created.
hook_field_create_instance drupal/modules/field/field.api.php Act on a field instance being created.
hook_field_delete drupal/modules/field/field.api.php Define custom delete behavior for this module's field data.
hook_field_delete_field drupal/modules/field/field.api.php Act on a field being deleted.
hook_field_delete_instance drupal/modules/field/field.api.php Act on a field instance being deleted.
hook_field_delete_revision drupal/modules/field/field.api.php Define custom revision delete behavior for this module's field types.
hook_field_display_alter drupal/modules/field/field.api.php Alters the display settings of a field before it gets displayed.
hook_field_display_ENTITY_TYPE_alter drupal/modules/field/field.api.php Alters the display settings of a field on a given entity type before it gets displayed.
hook_field_extra_fields drupal/modules/field/field.api.php Exposes "pseudo-field" components on fieldable entities.
hook_field_extra_fields_alter drupal/modules/field/field.api.php Alter "pseudo-field" components on fieldable entities.
hook_field_extra_fields_display_alter drupal/modules/field/field.api.php Alters the display settings of pseudo-fields before an entity is displayed.
hook_field_formatter_info drupal/modules/field/field.api.php Expose Field API formatter types.
hook_field_formatter_info_alter drupal/modules/field/field.api.php Perform alterations on Field API formatter types.
hook_field_formatter_prepare_view drupal/modules/field/field.api.php Allow formatters to load information for field values being displayed.
hook_field_formatter_view drupal/modules/field/field.api.php Build a renderable array for a field value.
hook_field_info drupal/modules/field/field.api.php Define Field API field types.
hook_field_info_alter drupal/modules/field/field.api.php Perform alterations on Field API field types.
hook_field_info_max_weight drupal/modules/field/field.api.php Returns the maximum weight for the entity components handled by the module.
hook_field_insert drupal/modules/field/field.api.php Define custom insert behavior for this module's field data.
hook_field_is_empty drupal/modules/field/field.api.php Define what constitutes an empty item for a field type.
hook_field_language_alter drupal/modules/field/field.api.php Perform alterations on field_language() values.
hook_field_load drupal/modules/field/field.api.php Define custom load behavior for this module's field types.
hook_field_prepare_translation drupal/modules/field/field.api.php Define custom prepare_translation behavior for this module's field types.
hook_field_prepare_view drupal/modules/field/field.api.php Prepare field values prior to display.
hook_field_presave drupal/modules/field/field.api.php Define custom presave behavior for this module's field types.
hook_field_purge_field drupal/modules/field/field.api.php Acts when a field record is being purged.
hook_field_purge_instance drupal/modules/field/field.api.php Acts when a field instance is being purged.
hook_field_read_field drupal/modules/field/field.api.php Act on field records being read from the database.
hook_field_read_instance drupal/modules/field/field.api.php Act on a field record being read from the database.
hook_field_schema drupal/modules/field/field.api.php Define the Field API schema for a field structure.
hook_field_storage_create_field drupal/modules/field/field.api.php Act on creation of a new field.
hook_field_storage_delete drupal/modules/field/field.api.php Delete all field data for an entity.
hook_field_storage_delete_field drupal/modules/field/field.api.php Act on deletion of a field.
hook_field_storage_delete_instance drupal/modules/field/field.api.php Act on deletion of a field instance.
hook_field_storage_delete_revision drupal/modules/field/field.api.php Delete a single revision of field data for an entity.
hook_field_storage_details drupal/modules/field/field.api.php Reveal the internal details about the storage for a field.
hook_field_storage_details_alter drupal/modules/field/field.api.php Perform alterations on Field API storage details.
hook_field_storage_info drupal/modules/field/field.api.php Expose Field API storage backends.
hook_field_storage_info_alter drupal/modules/field/field.api.php Perform alterations on Field API storage types.
hook_field_storage_load drupal/modules/field/field.api.php Load field data for a set of entities.
hook_field_storage_pre_insert drupal/modules/field/field.api.php Act before the storage backends insert field data.
hook_field_storage_pre_load drupal/modules/field/field.api.php Act before the storage backends load field data.
hook_field_storage_pre_update drupal/modules/field/field.api.php Act before the storage backends update field data.
hook_field_storage_purge drupal/modules/field/field.api.php Remove field storage information when field data is purged.
hook_field_storage_purge_field drupal/modules/field/field.api.php Remove field storage information when a field record is purged.
hook_field_storage_purge_field_instance drupal/modules/field/field.api.php Remove field storage information when a field instance is purged.
hook_field_storage_query drupal/modules/field/field.api.php Execute an EntityFieldQuery.
hook_field_storage_update_field drupal/modules/field/field.api.php Update the storage information for a field.
hook_field_storage_write drupal/modules/field/field.api.php Write field data for an entity.
hook_field_update drupal/modules/field/field.api.php Define custom update behavior for this module's field data.
hook_field_update_field drupal/modules/field/field.api.php Act on a field being updated.
hook_field_update_forbid drupal/modules/field/field.api.php Forbid a field update from occurring.
hook_field_update_instance drupal/modules/field/field.api.php Act on a field instance being updated.
hook_field_validate drupal/modules/field/field.api.php Validate this module's field data.
hook_field_widget_error drupal/modules/field/field.api.php Flag a field-level validation error.
hook_field_widget_form drupal/modules/field/field.api.php Return the form for a single field widget.
hook_field_widget_form_alter drupal/modules/field/field.api.php Alter forms for field widgets provided by other modules.
hook_field_widget_info drupal/modules/field/field.api.php Expose Field API widget types.
hook_field_widget_info_alter drupal/modules/field/field.api.php Perform alterations on Field API widget types.
hook_field_widget_properties_alter drupal/modules/field/field.api.php Alters the widget properties of a field instance before it gets displayed.
hook_field_widget_properties_ENTITY_TYPE_alter drupal/modules/field/field.api.php Alters the widget properties of a field instance on a given entity type before it gets displayed.
hook_field_widget_WIDGET_TYPE_form_alter drupal/modules/field/field.api.php Alter widget forms for a specific widget provided by another module.
hook_filetransfer_info drupal/modules/system/system.api.php Register information about FileTransfer classes provided by a module.
hook_filetransfer_info_alter drupal/modules/system/system.api.php Alter the FileTransfer class registry.
hook_file_copy drupal/modules/system/system.api.php Respond to a file that has been copied.
hook_file_delete drupal/modules/system/system.api.php Respond to a file being deleted.
hook_file_download drupal/modules/system/system.api.php Control access to private file downloads and specify HTTP headers.
hook_file_insert drupal/modules/system/system.api.php Respond to a file being added.
hook_file_load drupal/modules/system/system.api.php Load additional information into file objects.
hook_file_mimetype_mapping_alter drupal/modules/system/system.api.php Alter MIME type mappings used to determine MIME type from a file extension.
hook_file_move drupal/modules/system/system.api.php Respond to a file that has been moved.
hook_file_presave drupal/modules/system/system.api.php Act on a file being inserted or updated.
hook_file_update drupal/modules/system/system.api.php Respond to a file being updated.
hook_file_url_alter drupal/modules/system/system.api.php Alter the URL to a file.
hook_file_validate drupal/modules/system/system.api.php Check that files meet a given criteria.
hook_filter_format_disable drupal/modules/filter/filter.api.php Perform actions when a text format has been disabled.
hook_filter_format_insert drupal/modules/filter/filter.api.php Perform actions when a new text format has been created.
hook_filter_format_update drupal/modules/filter/filter.api.php Perform actions when a text format has been updated.
hook_filter_info drupal/modules/filter/filter.api.php Define content filters.
hook_filter_info_alter drupal/modules/filter/filter.api.php Perform alterations on filter definitions.
hook_flush_caches drupal/modules/system/system.api.php Add a list of cache tables to be cleared.
hook_form drupal/modules/node/node.api.php Display a node editing form.
hook_forms drupal/modules/system/system.api.php Map form_ids to form builder functions.
hook_form_alter drupal/modules/system/system.api.php Perform alterations before a form is rendered.
hook_form_BASE_FORM_ID_alter drupal/modules/system/system.api.php Provide a form-specific alteration for shared ('base') forms.
hook_form_FORM_ID_alter drupal/modules/system/system.api.php Provide a form-specific alteration instead of the global hook_form_alter().
hook_help drupal/modules/system/system.api.php Provide online user help.
hook_hook_info drupal/modules/system/system.api.php Defines one or more hooks that are exposed by a module.
hook_hook_info_alter drupal/modules/system/system.api.php Alter information from hook_hook_info().
hook_html_head_alter drupal/modules/system/system.api.php Alter XHTML HEAD tags before they are rendered by drupal_get_html_head().
hook_image_default_styles drupal/modules/image/image.api.php Provide module-based image styles for reuse throughout Drupal.
hook_image_effect_info drupal/modules/image/image.api.php Define information about image effects provided by a module.
hook_image_effect_info_alter drupal/modules/image/image.api.php Alter the information provided in hook_image_effect_info().
hook_image_styles_alter drupal/modules/image/image.api.php Modify any image styles provided by other modules or the user.
hook_image_style_delete drupal/modules/image/image.api.php Respond to image style deletion.
hook_image_style_flush drupal/modules/image/image.api.php Respond to image style flushing.
hook_image_style_save drupal/modules/image/image.api.php Respond to image style updating.
hook_image_toolkits drupal/modules/system/system.api.php Define image toolkits provided by this module.
hook_init drupal/modules/system/system.api.php Perform setup tasks for non-cached page requests.
hook_insert drupal/modules/node/node.api.php Respond to creation of a new node.
hook_install drupal/modules/system/system.api.php Perform setup tasks when the module is installed.
hook_install_tasks drupal/modules/system/system.api.php Return an array of tasks to be performed by an installation profile.
hook_install_tasks_alter drupal/modules/system/system.api.php Alter the full list of installation tasks.
hook_js_alter drupal/modules/system/system.api.php Perform necessary alterations to the JavaScript before it is presented on the page.
hook_language_fallback_candidates_alter drupal/modules/system/language.api.php Perform alterations on the language fallback candidates.
hook_language_init drupal/modules/system/language.api.php Allows modules to act after language initialization has been performed.
hook_language_negotiation_info drupal/modules/system/language.api.php Define language negotiation providers.
hook_language_negotiation_info_alter drupal/modules/system/language.api.php Perform alterations on language negoiation providers.
hook_language_switch_links_alter drupal/modules/system/language.api.php Perform alterations on language switcher links.
hook_language_types_info drupal/modules/system/language.api.php Define language types.
hook_language_types_info_alter drupal/modules/system/language.api.php Perform alterations on language types.
hook_library drupal/modules/system/system.api.php Registers JavaScript/CSS libraries associated with a module.
hook_library_alter drupal/modules/system/system.api.php Alters the JavaScript/CSS library registry.
hook_load drupal/modules/node/node.api.php Act on nodes being loaded from the database.
hook_locale drupal/modules/locale/locale.api.php Allows modules to define their own text groups that can be translated.
hook_mail drupal/modules/system/system.api.php Prepare a message based on parameters; called from drupal_mail().
hook_mail_alter drupal/modules/system/system.api.php Alter an email message created with the drupal_mail() function.
hook_menu drupal/modules/system/system.api.php Define menu items and page callbacks.
hook_menu_alter drupal/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/modules/system/system.api.php Alter links in the active trail before it is rendered as the breadcrumb.
hook_menu_contextual_links_alter drupal/modules/system/system.api.php Alter contextual links before they are rendered.
hook_menu_delete drupal/modules/menu/menu.api.php Respond to a custom menu deletion.
hook_menu_get_item_alter drupal/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/modules/menu/menu.api.php Respond to a custom menu creation.
hook_menu_link_alter drupal/modules/system/system.api.php Alter the data being saved to the {menu_links} table by menu_link_save().
hook_menu_link_delete drupal/modules/system/system.api.php Inform modules that a menu link has been deleted.
hook_menu_link_insert drupal/modules/system/system.api.php Inform modules that a menu link has been created.
hook_menu_link_update drupal/modules/system/system.api.php Inform modules that a menu link has been updated.
hook_menu_local_tasks_alter drupal/modules/system/system.api.php Alter tabs and actions displayed on the page before they are rendered.
hook_menu_site_status_alter drupal/modules/system/system.api.php Control site status before menu dispatching.
hook_menu_update drupal/modules/menu/menu.api.php Respond to a custom menu update.
hook_modules_disabled drupal/modules/system/system.api.php Perform necessary actions after modules are disabled.
hook_modules_enabled drupal/modules/system/system.api.php Perform necessary actions after modules are enabled.
hook_modules_installed drupal/modules/system/system.api.php Perform necessary actions after modules are installed.
hook_modules_uninstalled drupal/modules/system/system.api.php Perform necessary actions after modules are uninstalled.
hook_module_implements_alter drupal/modules/system/system.api.php Alter the registry of modules implementing a hook.
hook_multilingual_settings_changed drupal/modules/locale/locale.api.php Allow modules to react to language settings changes.
hook_node_access drupal/modules/node/node.api.php Control access to a node.
hook_node_access_records drupal/modules/node/node.api.php Set permissions for a node to be written to the database.
hook_node_access_records_alter drupal/modules/node/node.api.php Alter permissions for a node before it is written to the database.
hook_node_delete drupal/modules/node/node.api.php Respond to node deletion.
hook_node_grants drupal/modules/node/node.api.php Inform the node access system what permissions the user has.
hook_node_grants_alter drupal/modules/node/node.api.php Alter user access rules when trying to view, edit or delete a node.
hook_node_info drupal/modules/node/node.api.php Define module-provided node types.
hook_node_insert drupal/modules/node/node.api.php Respond to creation of a new node.
hook_node_load drupal/modules/node/node.api.php Act on arbitrary nodes being loaded from the database.
hook_node_operations drupal/modules/node/node.api.php Add mass node operations.
hook_node_prepare drupal/modules/node/node.api.php Act on a node object about to be shown on the add/edit form.
hook_node_presave drupal/modules/node/node.api.php Act on a node being inserted or updated.
hook_node_revision_delete drupal/modules/node/node.api.php Respond to deletion of a node revision.
hook_node_search_result drupal/modules/node/node.api.php Act on a node being displayed as a search result.
hook_node_submit drupal/modules/node/node.api.php Act on a node after validated form values have been copied to it.
hook_node_type_delete drupal/modules/node/node.api.php Respond to node type deletion.
hook_node_type_insert drupal/modules/node/node.api.php Respond to node type creation.
hook_node_type_update drupal/modules/node/node.api.php Respond to node type updates.
hook_node_update drupal/modules/node/node.api.php Respond to updates to a node.
hook_node_update_index drupal/modules/node/node.api.php Act on a node being indexed for searching.
hook_node_validate drupal/modules/node/node.api.php Perform node validation before a node is created or updated.
hook_node_view drupal/modules/node/node.api.php Act on a node that is being assembled before rendering.
hook_node_view_alter drupal/modules/node/node.api.php Alter the results of node_view().
hook_openid drupal/modules/openid/openid.api.php Allow modules to modify the OpenID request parameters.
hook_openid_discovery_method_info drupal/modules/openid/openid.api.php Allow modules to declare OpenID discovery methods.
hook_openid_discovery_method_info_alter drupal/modules/openid/openid.api.php Allow modules to alter discovery methods.
hook_openid_normalization_method_info drupal/modules/openid/openid.api.php Allow modules to declare OpenID normalization methods.
hook_openid_normalization_method_info_alter drupal/modules/openid/openid.api.php Allow modules to alter normalization methods.
hook_openid_response drupal/modules/openid/openid.api.php Allow modules to act upon a successful OpenID login.
hook_overlay_child_initialize drupal/modules/overlay/overlay.api.php Allow modules to act when an overlay child window is initialized.
hook_overlay_parent_initialize drupal/modules/overlay/overlay.api.php Allow modules to act when an overlay parent window is initialized.
hook_page_alter drupal/modules/system/system.api.php Perform alterations before a page is rendered.
hook_page_build drupal/modules/system/system.api.php Add elements to a page before it is rendered.
hook_page_delivery_callback_alter drupal/modules/system/system.api.php Alters the delivery callback used to send the result of the page callback to the browser.
hook_path_delete drupal/modules/path/path.api.php Respond to a path being deleted.
hook_path_insert drupal/modules/path/path.api.php Respond to a path being inserted.
hook_path_update drupal/modules/path/path.api.php Respond to a path being updated.
hook_permission drupal/modules/system/system.api.php Define user permissions.
hook_prepare drupal/modules/node/node.api.php Act on a node object about to be shown on the add/edit form.
hook_query_alter drupal/modules/system/system.api.php Perform alterations to a structured query.
hook_query_TAG_alter drupal/modules/system/system.api.php Perform alterations to a structured query for a given tag.
hook_ranking drupal/modules/node/node.api.php Provide additional methods of scoring for core search results for nodes.
hook_rdf_mapping drupal/modules/rdf/rdf.api.php Allow modules to define RDF mappings for field bundles.
hook_rdf_namespaces drupal/modules/rdf/rdf.api.php Allow modules to define namespaces for RDF mappings.
hook_registry_files_alter drupal/modules/system/system.api.php Perform necessary alterations to the list of files parsed by the registry.
hook_requirements drupal/modules/system/system.api.php Check installation requirements and do status reporting.
hook_schema drupal/modules/system/system.api.php Define the current version of the database schema.
hook_schema_alter drupal/modules/system/system.api.php Perform alterations to existing database schemas.
hook_search_access drupal/modules/search/search.api.php Define access to a custom search routine.
hook_search_admin drupal/modules/search/search.api.php Add elements to the search settings form.
hook_search_execute drupal/modules/search/search.api.php Execute a search for a set of key words.
hook_search_info drupal/modules/search/search.api.php Define a custom search type.
hook_search_page drupal/modules/search/search.api.php Override the rendering of search results.
hook_search_preprocess drupal/modules/search/search.api.php Preprocess text for search.
hook_search_reset drupal/modules/search/search.api.php Take action when the search index is going to be rebuilt.
hook_search_status drupal/modules/search/search.api.php Report the status of indexing.
hook_shortcut_default_set drupal/modules/shortcut/shortcut.api.php Return the name of a default shortcut set for the provided user account.
hook_simpletest_alter drupal/modules/simpletest/simpletest.api.php Alter the list of tests.
hook_stream_wrappers drupal/modules/system/system.api.php Registers PHP stream wrapper implementations associated with a module.
hook_stream_wrappers_alter drupal/modules/system/system.api.php Alters the list of PHP stream wrapper implementations.
hook_system_info_alter drupal/modules/system/system.api.php Alter the information parsed from module and theme .info files
hook_system_themes_page_alter drupal/modules/system/system.api.php Alters theme operation links.
hook_system_theme_engine_info drupal/modules/system/system.api.php Return additional theme engines provided by modules.
hook_system_theme_info drupal/modules/system/system.api.php Return additional themes provided by modules.
hook_taxonomy_term_delete drupal/modules/taxonomy/taxonomy.api.php Respond to the deletion of taxonomy terms.
hook_taxonomy_term_insert drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when inserted.
hook_taxonomy_term_load drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when loaded.
hook_taxonomy_term_presave drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy terms before they are saved.
hook_taxonomy_term_update drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy terms when updated.
hook_taxonomy_term_view drupal/modules/taxonomy/taxonomy.api.php Act on a taxonomy term that is being assembled before rendering.
hook_taxonomy_term_view_alter drupal/modules/taxonomy/taxonomy.api.php Alter the results of taxonomy_term_view().
hook_taxonomy_vocabulary_delete drupal/modules/taxonomy/taxonomy.api.php Respond to the deletion of taxonomy vocabularies.
hook_taxonomy_vocabulary_insert drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when inserted.
hook_taxonomy_vocabulary_load drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when loaded.
hook_taxonomy_vocabulary_presave drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies before they are saved.
hook_taxonomy_vocabulary_update drupal/modules/taxonomy/taxonomy.api.php Act on taxonomy vocabularies when updated.
hook_test_finished drupal/modules/simpletest/simpletest.api.php An individual test has finished.
hook_test_group_finished drupal/modules/simpletest/simpletest.api.php A test group has finished.
hook_test_group_started drupal/modules/simpletest/simpletest.api.php A test group has started.
hook_theme drupal/modules/system/system.api.php Register a module (or theme's) theme implementations.
hook_theme_registry_alter drupal/modules/system/system.api.php Alter the theme registry information returned from hook_theme().
hook_tokens drupal/modules/system/system.api.php Provide replacement values for placeholder tokens.
hook_tokens_alter drupal/modules/system/system.api.php Alter replacement values for placeholder tokens.
hook_token_info drupal/modules/system/system.api.php Provide information about available placeholder tokens and token types.
hook_token_info_alter drupal/modules/system/system.api.php Alter the metadata about available placeholder tokens and token types.
hook_translated_menu_link_alter drupal/modules/system/system.api.php Alter a menu link after it has been translated and before it is rendered.
hook_trigger_info drupal/modules/trigger/trigger.api.php Declare triggers (events) for users to assign actions to.
hook_trigger_info_alter drupal/modules/trigger/trigger.api.php Alter triggers declared by hook_trigger_info().
hook_uninstall drupal/modules/system/system.api.php Remove any information that the module sets.
hook_update drupal/modules/node/node.api.php Respond to updates to a node.
hook_updater_info drupal/modules/system/system.api.php Provide information on Updaters (classes that can update Drupal).
hook_updater_info_alter drupal/modules/system/system.api.php Alter the Updater information array.
hook_update_dependencies drupal/modules/system/system.api.php Return an array of information about module update dependencies.
hook_update_index drupal/modules/search/search.api.php Update the search index for this module.
hook_update_last_removed drupal/modules/system/system.api.php Return a number which is no longer available as hook_update_N().
hook_update_N drupal/modules/system/system.api.php Perform a single update.
hook_update_projects_alter drupal/modules/update/update.api.php Alter the list of projects before fetching data and comparing versions.
hook_update_status_alter drupal/modules/update/update.api.php Alter the information about available updates for projects.
hook_url_inbound_alter drupal/modules/system/system.api.php Alters inbound URL requests.
hook_url_outbound_alter drupal/modules/system/system.api.php Alters outbound URLs.
hook_username_alter drupal/modules/system/system.api.php Alter the username that is displayed for a user.
hook_user_cancel drupal/modules/user/user.api.php Act on user account cancellations.
hook_user_cancel_methods_alter drupal/modules/user/user.api.php Modify account cancellation methods.
hook_user_categories drupal/modules/user/user.api.php Define a list of user settings or profile information categories.
hook_user_delete drupal/modules/user/user.api.php Respond to user deletion.
hook_user_insert drupal/modules/user/user.api.php A user account was created.
hook_user_load drupal/modules/user/user.api.php Act on user objects when loaded from the database.
hook_user_login drupal/modules/user/user.api.php The user just logged in.
hook_user_logout drupal/modules/user/user.api.php The user just logged out.
hook_user_operations drupal/modules/user/user.api.php Add mass user operations.
hook_user_presave drupal/modules/user/user.api.php A user account is about to be created or updated.
hook_user_role_delete drupal/modules/user/user.api.php Respond to user role deletion.
hook_user_role_insert drupal/modules/user/user.api.php Respond to creation of a new user role.
hook_user_role_presave drupal/modules/user/user.api.php Act on a user role being inserted or updated.
hook_user_role_update drupal/modules/user/user.api.php Respond to updates to a user role.
hook_user_update drupal/modules/user/user.api.php A user account was updated.
hook_user_view drupal/modules/user/user.api.php The user's account information is being displayed.
hook_user_view_alter drupal/modules/user/user.api.php The user was built; the module may modify the structured content.
hook_validate drupal/modules/node/node.api.php Perform node validation before a node is created or updated.
hook_verify_update_archive drupal/modules/update/update.api.php Verify an archive after it has been downloaded and extracted.
hook_view drupal/modules/node/node.api.php Display a node.
hook_watchdog drupal/modules/system/system.api.php Log an event message.
hook_xmlrpc drupal/modules/system/system.api.php Register XML-RPC callbacks.
hook_xmlrpc_alter drupal/modules/system/system.api.php Alters the definition of XML-RPC methods before they are called.
module_hook drupal/includes/module.inc Determines whether a module implements a hook.
module_hook_info drupal/includes/module.inc Retrieves a list of hooks that are declared through hook_hook_info().
module_implements drupal/includes/module.inc Determines which modules are implementing a hook.
module_implements_write_cache drupal/includes/module.inc Writes the hook implementation cache.
module_invoke drupal/includes/module.inc Invokes a hook in a particular module.
module_invoke_all drupal/includes/module.inc Invokes a hook in all enabled modules that implement it.

Sub-Topics

Namesort descending Location Description
Callbacks drupal/includes/module.inc Callback function signatures.
Field Formatter API drupal/modules/field/field.api.php Define Field API formatter types.
Field Types API drupal/modules/field/field.api.php Define field types.
Field Widget API drupal/modules/field/field.api.php Define Field API widget types.