Registration 
Edit
Block registration API reference.
Note: You can use the functions documented on this page to register a block on the client-side only, but a flexible method to register new block types is to use the block.json metadata file. See metadata documentation for complete information.
registerBlockType registerBlockType
- Type:
Function
Every block starts by registering a new block type definition. To register, you use the registerBlockType function from the wp-blocks package. The function takes two arguments, a block name and a block configuration object.
Block Name Block Name
- Type:
String
The name for a block is a unique string that identifies a block. Names have to be structured as namespace/block-name, where namespace is the name of your plugin or theme.
// Registering my block with a unique name
registerBlockType( 'my-plugin/book', {} );
Note: A block name can only contain lowercase alphanumeric characters and dashes, and must begin with a letter.
Note: This name is used on the comment delimiters as <!-- wp:my-plugin/book -->. Those blocks provided by core don’t include a namespace when serialized.
Block Configuration Block Configuration
- Type:
Object[{ key: value }]
A block requires a few properties to be specified before it can be registered successfully. These are defined through a configuration object, which includes the following:
title title
- Type:
String
This is the display title for your block, which can be translated with our translation functions. The block inserter will show this name.
// Our data object title: __( 'Book' );
description (optional) description (optional)
- Type:
String
This is a short description for your block, which can be translated with our translation functions. This will be shown in the Block Tab in the Settings Sidebar.
description: __( 'Block showing a Book card.' );
category category
- Type:
String[ text | media | design | widgets | theme | embed ]
Blocks are grouped into categories to help users browse and discover them.
The core provided categories are:
- text
- media
- design
- widgets
- theme
- embed
// Assigning to the 'widgets' category category: 'widgets',
Plugins and Themes can also register custom block categories.
icon (optional) icon (optional)
- Type:
String|Object
An icon property should be specified to make it easier to identify a block. These can be any of WordPress’ Dashicons, or a custom svg element.
// Specifying a dashicon for the block icon: 'book-alt', // Specifying a custom svg for the block icon: <svg viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><path fill="none" d="M0 0h24v24H0V0z" /><path d="M19 13H5v-2h14v2z" /></svg>,
Note: Custom SVG icons are automatically wrapped in the wp.primitives.SVG component to add accessibility attributes (aria-hidden, role, and focusable).
An object can also be passed as icon, in this case, icon, as specified above, should be included in the src property.
Besides src the object can contain background and foreground colors, this colors will appear with the icon when they are applicable e.g.: in the inserter.
icon: {
// Specifying a background color to appear with the icon e.g.: in the inserter.
background: '#7e70af',
// Specifying a color for the icon (optional: if not set, a readable color will be automatically defined)
foreground: '#fff',
// Specifying an icon for the block
src: <svg viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><path fill="none" d="M0 0h24v24H0V0z" /><path d="M19 13H5v-2h14v2z" /></svg>,
} ,
keywords (optional) keywords (optional)
- Type:
Array
Sometimes a block could have aliases that help users discover it while searching. For example, an image block could also want to be discovered by photo. You can do so by providing an array of terms (which can be translated).
// Make it easier to discover a block with keyword aliases. // These can be localised so your keywords work across locales. keywords: [ __( 'image' ), __( 'photo' ), __( 'pics' ) ],
styles (optional) styles (optional)
- Type:
Array
Block styles can be used to provide alternative styles to block. It works by adding a class name to the block’s wrapper. Using CSS, a theme developer can target the class name for the block style if it is selected.
// Register block styles.
styles: [
// Mark style as default.
{
name: 'default',
label: __( 'Rounded' ),
isDefault: true
},
{
name: 'outline',
label: __( 'Outline' )
},
{
name: 'squared',
label: __( 'Squared' )
},
],
Plugins and Themes can also register custom block style for existing blocks.
attributes (optional) attributes (optional)
- Type:
Object
Attributes provide the structured data needs of a block. They can exist in different forms when they are serialized, but they are declared together under a common interface.
// Specifying my block attributes
attributes: {
cover: {
type: 'string',
source: 'attribute',
selector: 'img',
attribute: 'src',
},
author: {
type: 'string',
source: 'html',
selector: '.book-author',
},
pages: {
type: 'number',
},
},
- See: Attributes.
example (optional) example (optional)
- Type:
Object
Example provides structured example data for the block. This data is used to construct a preview for the block to be shown in the Inspector Help Panel when the user mouses over the block.
The data provided in the example object should match the attributes defined. For example:
example: {
attributes: {
cover: 'https://example.com/image.jpg',
author: 'William Shakespeare',
pages: 500
},
},
If example is not defined, the preview will not be shown. So even if no-attributes are defined, setting a empty example object example: {} will trigger the preview to show.
It’s also possible to extend the block preview with inner blocks via innerBlocks. For example:
example: {
attributes: {
cover: 'https://example.com/image.jpg',
},
innerBlocks: [
{
name: 'core/paragraph',
attributes: {
/* translators: example text. */
content: __(
'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Praesent et eros eu felis.'
),
},
},
],
},
It’s also possible to define the width of the preview container in pixels via viewportWidth. For example:
example: {
attributes: {
cover: 'https://example.com/image.jpg',
},
viewportWidth: 800
},
variations (optional) variations (optional)
- Type:
Object[]
Similarly to how the block’s styles can be declared, a block type can define block variations that the user can pick from. The difference is that, rather than changing only the visual appearance, this field provides a way to apply initial custom attributes and inner blocks at the time when a block is inserted. See the Block Variations API for more details.
supports (optional) supports (optional)
- Type:
Object
Supports contains as set of options to control features used in the editor. See the the supports documentation for more details.
transforms (optional) transforms (optional)
- Type:
Object
Transforms provide rules for what a block can be transformed from and what it can be transformed to. A block can be transformed from another block, a shortcode, a regular expression, a file or a raw DOM node. Take a look at the Block Transforms API for more info about each available transformation.
parent (optional) parent (optional)
- Type:
Array
Blocks are able to be inserted into blocks that use InnerBlocks as nested content. Sometimes it is useful to restrict a block so that it is only available as a nested block. For example, you might want to allow an ‘Add to Cart’ block to only be available within a ‘Product’ block.
Setting parent lets a block require that it is only available when nested within the specified blocks.
// Only allow this block when it is nested in a Columns block parent: [ 'core/columns' ],
Block Collections Block Collections
registerBlockCollection registerBlockCollection
- Type:
Function
Blocks can be added to collections, grouping together all blocks from the same origin
registerBlockCollection takes two parameters, namespace and an object of settings including title and icon.
Namespace Namespace
- Type:
String
This should match the namespace declared in the block name; the name of your plugin or theme.
Settings Settings
Title Title
- Type:
String
This will display in the block inserter section, which will list all blocks in this collection.
Icon Icon
- Type:
Object
(Optional) An icon to display alongside the title in the block inserter.
// Registering a block collection
registerBlockCollection( 'my-plugin', { title: 'My Plugin' } );