aws-crt

/** * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. * SPDX-License-Identifier: Apache-2.0. */ import * as WebsocketUtils from "./ws"; import { BufferedEventEmitter } from "../common/event"; import { CrtError } from "../browser"; import { ClientBootstrap, SocketOptions } from "./io"; import { QoS, Payload, MqttRequest, MqttSubscribeRequest, MqttWill, OnMessageCallback } from "../common/mqtt"; export { QoS, Payload, MqttRequest, MqttSubscribeRequest, MqttWill } from "../common/mqtt"; /** @category MQTT */ export declare type WebsocketOptions = WebsocketUtils.WebsocketOptions; /** @category MQTT */ export declare type AWSCredentials = WebsocketUtils.AWSCredentials; /** * Configuration options for an MQTT connection * * @module aws-crt * @category MQTT */ export interface MqttConnectionConfig { /** * ID to place in CONNECT packet. Must be unique across all devices/clients. * If an ID is already in use, the other client will be disconnected. */ client_id: string; /** Server name to connect to */ host_name: string; /** Server port to connect to */ port: number; /** Socket options, ignored in browser */ socket_options: SocketOptions; /** * Whether or not to start a clean session with each reconnect. * If True, the server will forget all subscriptions with each reconnect. * Set False to request that the server resume an existing session * or start a new session that may be resumed after a connection loss. * The `session_present` bool in the connection callback informs * whether an existing session was successfully resumed. * If an existing session is resumed, the server remembers previous subscriptions * and sends mesages (with QoS1 or higher) that were published while the client was offline. */ clean_session?: boolean; /** * The keep alive value, in seconds, to send in CONNECT packet. * A PING will automatically be sent at this interval. * The server will assume the connection is lost if no PING is received after 1.5X this value. * This duration must be longer than {@link timeout}. */ keep_alive?: number; /** * Milliseconds to wait for ping response before client assumes * the connection is invalid and attempts to reconnect. * This duration must be shorter than keep_alive_secs. * Alternatively, TCP keep-alive via :attr:`SocketOptions.keep_alive` * may accomplish this in a more efficient (low-power) scenario, * but keep-alive options may not work the same way on every platform and OS version. */ ping_timeout?: number; /** * Milliseconds to wait for the response to the operation requires response by protocol. * Set to zero to disable timeout. Otherwise, the operation will fail if no response is * received within this amount of time after the packet is written to the socket. * It applied to PUBLISH (QoS>0) and UNSUBSCRIBE now. */ protocol_operation_timeout?: number; /** * Will to send with CONNECT packet. The will is * published by the server when its connection to the client is unexpectedly lost. */ will?: MqttWill; /** Username to connect with */ username?: string; /** Password to connect with */ password?: string; /** Options for the underlying websocket connection */ websocket?: WebsocketOptions; /** AWS credentials, which will be used to sign the websocket request */ credentials?: AWSCredentials; } /** * MQTT client * * @module aws-crt * @category MQTT */ export declare class MqttClient { constructor(bootstrap?: ClientBootstrap); /** * Creates a new {@link MqttClientConnection} * @param config Configuration for the connection * @returns A new connection */ new_connection(config: MqttConnectionConfig): MqttClientConnection; } /** * MQTT client connection * * @module aws-crt * @category MQTT */ export declare class MqttClientConnection extends BufferedEventEmitter { readonly client: MqttClient; private config; private connection; private subscriptions; private connection_count; /** * @param client The client that owns this connection * @param config The configuration for this connection */ constructor(client: MqttClient, config: MqttConnectionConfig); /** Emitted when the connection is ready and is about to start sending response data */ on(event: 'connect', listener: (session_present: boolean) => void): this; /** Emitted when connection has closed sucessfully. */ on(event: 'disconnect', listener: () => void): this; /** * Emitted when an error occurs * @param error - A CrtError containing the error that occurred */ on(event: 'error', listener: (error: CrtError) => void): this; /** * Emitted when the connection is dropped unexpectedly. The error will contain the error * code and message. */ on(event: 'interrupt', listener: (error: CrtError) => void): this; /** * Emitted when the connection reconnects. Only triggers on connections after the initial one. */ on(event: 'resume', listener: (return_code: number, session_present: boolean) => void): this; /** * Emitted when any MQTT publish message arrives. */ on(event: 'message', listener: OnMessageCallback): this; private on_connect; private on_online; private on_offline; private on_disconnected; private on_error; private on_message; /** * Open the actual connection to the server (async). * @returns A Promise which completes whether the connection succeeds or fails. * If connection fails, the Promise will reject with an exception. * If connection succeeds, the Promise will return a boolean that is * true for resuming an existing session, or false if the session is new */ connect(): Promise<boolean>; /** * The connection will automatically reconnect. To cease reconnection attempts, call {@link disconnect}. * To resume the connection, call {@link connect}. * @deprecated */ reconnect(): Promise<boolean>; /** * Publish message (async). * If the device is offline, the PUBLISH packet will be sent once the connection resumes. * * @param topic Topic name * @param payload Contents of message * @param qos Quality of Service for delivering this message * @param retain If true, the server will store the message and its QoS so that it can be * delivered to future subscribers whose subscriptions match the topic name * @returns Promise which returns a {@link MqttRequest} which will contain the packet id of * the PUBLISH packet. * * * For QoS 0, completes as soon as the packet is sent. * * For QoS 1, completes when PUBACK is received. * * For QoS 2, completes when PUBCOMP is received. */ publish(topic: string, payload: Payload, qos: QoS, retain?: boolean): Promise<MqttRequest>; /** * Subscribe to a topic filter (async). * The client sends a SUBSCRIBE packet and the server responds with a SUBACK. * * subscribe() may be called while the device is offline, though the async * operation cannot complete successfully until the connection resumes. * * Once subscribed, `callback` is invoked each time a message matching * the `topic` is received. It is possible for such messages to arrive before * the SUBACK is received. * * @param topic Subscribe to this topic filter, which may include wildcards * @param qos Maximum requested QoS that server may use when sending messages to the client. * The server may grant a lower QoS in the SUBACK * @param on_message Optional callback invoked when message received. * @returns Promise which returns a {@link MqttSubscribeRequest} which will contain the * result of the SUBSCRIBE. The Promise resolves when a SUBACK is returned * from the server or is rejected when an exception occurs. */ subscribe(topic: string, qos: QoS, on_message?: OnMessageCallback): Promise<MqttSubscribeRequest>; /** * Unsubscribe from a topic filter (async). * The client sends an UNSUBSCRIBE packet, and the server responds with an UNSUBACK. * @param topic The topic filter to unsubscribe from. May contain wildcards. * @returns Promise wihch returns a {@link MqttRequest} which will contain the packet id * of the UNSUBSCRIBE packet being acknowledged. Promise is resolved when an * UNSUBACK is received from the server or is rejected when an exception occurs. */ unsubscribe(topic: string): Promise<MqttRequest>; /** * Close the connection (async). * @returns Promise which completes when the connection is closed. */ disconnect(): Promise<unknown>; }