import type { RequestHandler } from 'express';
/**
 * Builds an express middleware that checks the content-type header of requests with bodies.
 *
 * If the request has no body (as determined by the `type-is` library's
 * `hasBody` function), this middleware passes it along to the next in line.
 *
 * If the request has a body, it checks whether the content-type matches one of
 * the accepted content types, returning a 415 if it doesn't.
 *
 * If the request has a body, but not no content-type header, it will modify the
 * request and add the first accepted content type as the content-type header,
 * passing it along to the next request handler.
 *
 * @param {String} acceptedContentTypes - The list of content-types the middleware
 * should accept. Defaults to ['application/json'] if none are provided.
 *
 * @returns {function(Request, Response, NextFunction): void}
 */
export default function requireContentType(...acceptedContentTypes: string[]): RequestHandler;