/**
 * Filters for request body extraction
 * @packageDocumentation
 */
/// <reference types="node" />
import { Filter } from "../filter";
import { IsInstanceOf, Tuple } from "../types";
import { ParsedUrlQuery } from "querystring";
/**
 * Extracts the raw request body as a `Buffer`
 */
export declare const raw: Filter<[Buffer]>;
/**
 * Extracts the request body as a string
 */
export declare const text: Filter<[string]>;
/**
 * Possible values inside a schema for JSON body validation and extraction
 */
export declare type JsonSchema = typeof String | typeof Number | typeof Boolean | JsonSchema[] | {
    [key: string]: JsonSchema;
} | {
    optional: true;
    type: JsonSchema;
};
/**
 * Schema for JSON body validation and extraction
 */
export declare type RootJsonSchema = Tuple<JsonSchema> | {
    [key: string]: JsonSchema;
};
/**
 * Converts a [[`RootJsonSchema`]] to the type it represents
 *
 * Single element tuples will be translated to arrays.
 */
declare type JsonMap<S extends RootJsonSchema> = S extends [unknown] ? JsonMap<[S[0], []]>[0][] : {
    [K in keyof S]: true extends IsInstanceOf<S[K], string> ? string : true extends IsInstanceOf<S[K], number> ? number : true extends IsInstanceOf<S[K], boolean> ? boolean : S[K] extends RootJsonSchema ? JsonMap<S[K]> : S[K] extends {
        optional: true;
        type: infer T;
    } ? T extends JsonSchema ? true extends IsInstanceOf<T, string> ? string | undefined : true extends IsInstanceOf<T, number> ? number | undefined : true extends IsInstanceOf<T, boolean> ? boolean | undefined : T extends RootJsonSchema ? JsonMap<T> | undefined : never : never : never;
};
/**
 * Validates and extracts the request body as JSON following the provided schema
 *
 * ```ts
 * // Will match { "name": "Do the laundry", "done": false }
 * // Generic type annotation not required, only present for clarity's sake
 * const todo: Filter<[
 *     { name: string; description?: string; done: boolean }
 * ]> = json({
 *     name: String,
 *     description: { optional: true, type: String },
 *     done: Boolean,
 * });
 * ```
 *
 * @param schema - Schema
 * @param extra - Whether to include extra fields not diescribed in the schema in the extracted object
 */
export declare function json<T extends RootJsonSchema>(schema: T, extra?: boolean): Filter<[JsonMap<T>]>;
/**
 * Extracts the request body as JSON
 */
export declare const anyJson: Filter<[unknown]>;
/**
 * Extracts the request body as `application/x-www-form-urlencoded`
 */
export declare const form: Filter<[ParsedUrlQuery]>;
/**
 * `multipart/form-data` file
 */
export interface FormDataFile {
    /**
     * File contents
     */
    data: Buffer;
    /**
     * File name
     */
    filename: string;
    /**
     * Encoding of the data
     */
    encoding: string;
    /**
     * Mime type of the file
     */
    mime: string;
}
/**
 * `multipart/form-data` field
 */
export interface FormDataField {
    /**
     * Field value
     */
    value: string;
    /**
     * Encoding of the value
     */
    encoding: string;
    /**
     * Mime type of the value
     */
    mime: string;
}
/**
 * `multipart/form-data`
 */
export interface FormData {
    /**
     * Files indexed by their field name
     */
    files: {
        [key: string]: FormDataFile[];
    };
    /**
     * Fields indexed by their name
     */
    fields: {
        [key: string]: FormDataField[];
    };
}
/**
 * Extracts the request body as `multipart/form-data`
 */
export declare const multipart: Filter<[FormData]>;
export {};