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# Resource: Attribute Definition

# Type: Attribute Definition Object

# Link: https://dev.wix.com/docs/api-reference/business-solutions/bookings/resources/attributes/attribute-definition/attribute-definition-object.md

## Description: An attribute definition is a typed custom property (string, number, or boolean) that can be
applied to entities. Each definition has a display name shown to end users, a value type,
optional type-specific configuration (such as a list of allowed string values), and a
default value.

Attribute definitions are defined once per site. To set a value for a specific entity,
call Bulk Upsert Attribute Values; to read an entity's values together with their
definitions, call List Entity Attributes.

## Schema:

```json
 Type: Attribute Definition Object | type: AttributeDefinition
 Description: An attribute definition is a typed custom property (string, number, or boolean) that can be
applied to entities. Each definition has a display name shown to end users, a value type,
optional type-specific configuration (such as a list of allowed string values), and a
default value.

Attribute definitions are defined once per site. To set a value for a specific entity,
call Bulk Upsert Attribute Values; to read an entity's values together with their
definitions, call List Entity Attributes.
       - name: id  | type: string | description: Attribute definition ID.
       - name: revision  | type: string | description: Revision number, which increments by 1 each time the attribute definition is updated. To prevent conflicting changes, the current revision must be passed when updating. Ignored when creating an attribute definition.
           - name: value  | type: string | description: 
       - name: createdDate  | type: string | description: Date and time the attribute definition was created.
           - name: seconds  | type: string | description: 
           - name: nanos  | type: number | description: 
       - name: updatedDate  | type: string | description: Date and time the attribute definition was last updated.
       - name: name  | type: string | description: Display name for the attribute, shown to end users (for example, `Capacity`).  Must be unique within the site. Required when creating an attribute definition.
           - name: value  | type: string | description: 
       - name: valueType  | type: string | description: Value type of this attribute. Immutable after creation. `UpdateAttributeDefinition` rejects requests that change `value_type`. Required when creating an attribute definition.
           enum: STRING, NUMBER, BOOL
       - name: visibility  | type: boolean | description: Whether this attribute is shown to end users on the public site.  - `true`: shown in the UI and available for filtering. - `false`: hidden from end users. Back-office admins can still see and edit the attribute.  Default: `true`.
           - name: value  | type: boolean | description: 
       - name: defaultValue  | type: AttributeDefaultValue | description: Default value for the attribute. When a configuration change leaves a stored attribute value out of range or outside the allowed values, that value is reset to this default (see Update Attribute Definition).  The variant must match `valueType`. Required when creating an attribute definition.
       - name: extendedFields  | type: ExtendedFields | description: Custom field data for the attribute definition. [Extended fields](https://dev.wix.com/docs/rest/articles/getting-started/extended-fields.md) must be configured in the app dashboard before they can be accessed with API calls.
           - name: namespaces  | type: object | description: Extended field data. Each key corresponds to the namespace of the app that created the extended fields. The value of each key is structured according to the schema defined when the extended fields were configured.  You can only access fields for which you have the appropriate permissions.  Learn more about [extended fields](https://dev.wix.com/docs/rest/articles/getting-started/extended-fields.md).
       - name: tags  | type: Tags | description: Custom tags for organizing and filtering attribute definitions. Manage tags using `BulkUpdateAttributeDefinitionTags` or `BulkUpdateAttributeDefinitionTagsByFilter`.
           - name: privateTags  | type: TagList | description: Tags that require an additional permission in order to access them, normally not given to site members or visitors.
               - name: tagIds  | type: Array<string> | description: List of tag IDs.
           - name: publicTags  | type: TagList | description: Tags that are exposed to anyone who has access to the labeled entity itself, including site members and visitors.

```