/**
 * Module for AWS Authentication logic - signing http requests, events, chunks, etc...
 *
 * @packageDocumentation
 * @module auth
 * @mergeTarget
 */
import { AwsSigningConfigBase } from '../common/auth';
export { AwsSigningConfigBase } from '../common/auth';
/**
 * Standard AWS Credentials
 *
 * @category Auth
 */
export interface AWSCredentials {
    /** Optional region */
    aws_region?: string;
    /** AWS access id */
    aws_access_id: string;
    /** AWS secret access key */
    aws_secret_key: string;
    /** Session token for session credentials */
    aws_sts_token?: string;
}
/**
 * CredentialsProvider Base Class. The base class of credentials providers.
 *
 * @category Auth
 */
export declare class CredentialsProvider {
    /**
     * Return a valid credentials. Please note mqtt.js does not support promises, meaning that credentials
     * provider implementation should handle application-level authentication refreshing so that the websocket
     * connection could simply grab the latest valid tokens when getCredentials() get called.
     *
     * @Returns AWSCredentials
     *
     * */
    getCredentials(): AWSCredentials | undefined;
    /**
     * Invoked by browser MQTT clients before a connection is attempted.  Sub-classes that source credentials
     * asynchronously should override this API to perform asynchronous credentials resolution.
     *
     * Asynchronous providers that cache session-based credentials should resolve the returned promise if
     * the cached credentials are still valid.
     *
     * @returns a promise that resolves if credentials were successfully refreshed, rejected otherwise.
     */
    refreshCredentials(): Promise<void>;
}
/**
 * StaticCredentialProvider. The provider will always return the static AWSCredential.
 *
 * @category Auth
 */
export declare class StaticCredentialProvider extends CredentialsProvider {
    credentials: AWSCredentials;
    constructor(credentials: AWSCredentials);
    getCredentials: () => AWSCredentials | undefined;
}
/**
 * Configuration for use in browser credentials
 *
 * @category Auth
 */
export interface AwsSigningConfig extends AwsSigningConfigBase {
    credentials: AWSCredentials;
}