import { Metadata } from 'grpc-web';
/**
 * An extension of grpc-web.Metadata which provides a convenient way to
 * add an Authorization metadata header, and ensures every bearer token
 * going over the wire is prefixed with 'Bearer '
 */
declare class IlpCredentials implements Metadata {
    [s: string]: string;
    private static BEARER_PREFIX;
    /**
     * Static initializer, which constructs a new IlpCredentials object and adds
     * an Authorization entry.  If token is undefined, this builder will return
     * undefined, so no metadata will be passed to a network call. This allows applications
     * in the browser to rely on HTTP cookies to provide authentication.
     *
     * @param token an optional bearer token to be added to IlpCredentials
     * @return a new instance of IlpCredentials, with an Authorization header if token is defined,
     *          otherwise returns undefined
     */
    static build(token?: string): IlpCredentials | undefined;
}
export default IlpCredentials;