import { AttributeValue } from 'aws-sdk/clients/dynamodb';
import { Attribute } from '../attribute';
export interface AttributeMetadata<Value> {
    /**
     * Name for this attribute.
     *
     * When not set, the attribute name defaults to the property name used on the Table.
     */
    name?: string;
    /**
     * Optional extra data, used for your own logic.
     */
    extra?: any;
    /**
     * Makes this a required field, attempting to save a record without this value
     * will throw an error.
     *
     * This is primarily useful to prevent mistakes. Not designed as a primary means
     * of input validation.
     */
    required?: boolean;
    /**
     * Default value for this attribute.
     *
     * You can define a function that returns the default value.
     */
    default?: Value | (() => Value);
    /**
     * Manipulate the value whenever it is transformed into AttributeValue from Value
     */
    manipulateWrite?: (attributeValue: AttributeValue | null, value: Value | null, attribute: Attribute<any>) => AttributeValue | null;
    /**
     * Manipulate the value whenever it is read from the AttributeValue into Value
     */
    manipulateRead?: (value: Value | null, attributeValue: AttributeValue | null, attribute: Attribute<any>) => Value | null;
    /**
     * Define custom validation logic.
     *
     * When the value is invalid, this function should throw an error.
     * Optionally, it can return false and Dyngoose will throw an `ValidationError`.
     */
    validate?: (value: Value) => boolean;
}