declare type HttpMethod = "GET" | "POST" | "HEAD" | "PUT" | "DELETE" | "CONNECT" | "OPTIONS" | "TRACE" | "PATCH";
export interface CorsMiddlewareOptions {
    /**
     * Configures the Access-Control-Allow-Headers CORS header.
     * If not set will mirror Access-Control-Request-Headers from the request.
     */
    allowedHeaders?: string[] | null;
    /** Configures the Cache-Control header for the preflight response. */
    cacheControl?: string | null;
    /** Configures the Access-Control-Allow-Credentials CORS header. */
    allowCredentials?: boolean;
    /** Configures the Access-Control-Expose-Headers CORS header. */
    exposedHeaders?: string[];
    /** Configures the Access-Control-Max-Age CORS header. */
    maxAge?: number | null;
    /** Configures the Access-Control-Allow-Methods CORS header. */
    allowedMethods?: HttpMethod[];
    /** Provides a status code to use for successful OPTIONS requests, since some legacy browsers (IE11, various SmartTVs) choke on 204. */
    optionsSuccessStatus?: number;
    /** Configures the Access-Control-Allow-Origin CORS header. An empty array will set the header to '*'. */
    allowedOrigins?: (string | RegExp)[];
    /** Whether to call the next middleware or handler in case of a OPTIONS request. */
    preflightContinue?: boolean;
}
export declare function isCorsMiddlewareOptions(options: any): options is CorsMiddlewareOptions;
export {};