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aws-crt

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NodeJS/browser bindings to the aws-c-* libraries

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/** * @packageDocumentation * @module mqtt5 */ import * as mqtt5_packet from "./mqtt5_packet"; import { ICrtError } from "./error"; /** * Mqtt behavior settings that are dynamically negotiated as part of the CONNECT/CONNACK exchange. * * While you can infer all of these values from a combination of * 1. defaults as specified in the mqtt5 spec * 1. your CONNECT settings * 1. the CONNACK from the broker * * the client instead does the combining for you and emits a NegotiatedSettings object with final, authoritative values. * * Negotiated settings are communicated with every successful connection establishment. */ export interface NegotiatedSettings { /** * The maximum QoS allowed for publishes on this connection instance */ maximumQos: mqtt5_packet.QoS; /** * The amount of time in seconds the server will retain the MQTT session after a disconnect. */ sessionExpiryInterval: number; /** * The number of in-flight QoS 1 and QoS2 publications the server is willing to process concurrently. */ receiveMaximumFromServer: number; /** * The maximum packet size the server is willing to accept. */ maximumPacketSizeToServer: number; /** * The maximum amount of time in seconds between client packets. The client should use PINGREQs to ensure this * limit is not breached. The server will disconnect the client for inactivity if no MQTT packet is received * in a time interval equal to 1.5 x this value. */ serverKeepAlive: number; /** * Whether the server supports retained messages. */ retainAvailable: boolean; /** * Whether the server supports wildcard subscriptions. */ wildcardSubscriptionsAvailable: boolean; /** * Whether the server supports subscription identifiers */ subscriptionIdentifiersAvailable: boolean; /** * Whether the server supports shared subscriptions */ sharedSubscriptionsAvailable: boolean; /** * Whether the client has rejoined an existing session. */ rejoinedSession: boolean; /** * The final client id in use by the newly-established connection. This will be the configured client id if one * was given in the configuration, otherwise, if no client id was specified, this will be the client id assigned * by the server. Reconnection attempts will always use the auto-assigned client id, allowing for auto-assigned * session resumption. */ clientId: string; } /** * Controls how the MQTT5 client should behave with respect to MQTT sessions. */ export declare enum ClientSessionBehavior { /** Maps to Clean */ Default = 0, /** * Always ask for a clean session when connecting */ Clean = 1, /** * Always attempt to rejoin an existing session after an initial connection success. * * Session rejoin requires an appropriate non-zero session expiry interval in the client's CONNECT options. */ RejoinPostSuccess = 2, /** * Always attempt to rejoin an existing session. Since the client does not yet support durable session persistence, * this option is not guaranteed to be spec compliant because any unacknowledged qos1 publishes (which are * part of the client session state) will not be present on the initial connection. Until we support * durable session resumption, this option is technically spec-breaking, but useful. */ RejoinAlways = 3 } /** * Controls how the reconnect delay is modified in order to smooth out the distribution of reconnection attempt * timepoints for a large set of reconnecting clients. * * See [Exponential Backoff and Jitter](https://aws.amazon.com/blogs/architecture/exponential-backoff-and-jitter/) */ export declare enum RetryJitterType { /** * Maps to Full */ Default = 0, /** * Do not perform any randomization on the reconnect delay: * ```NextReconnectDelay = CurrentExponentialBackoffValue``` */ None = 1, /** * Fully random between no delay and the current exponential backoff value. * ```NextReconnectDelay = Random(0, CurrentExponentialBackoffValue)``` */ Full = 2, /** * ```NextReconnectDelay = Min(MaxReconnectDelay, Random(MinReconnectDelay, 3 * CurrentReconnectDelay)``` */ Decorrelated = 3 } /** * Payload of the Stopped event for the MQTT5 client. */ export interface StoppedEvent { } /** * Payload of the AttemptingConnect event for the MQTT5 client. */ export interface AttemptingConnectEvent { } /** * Payload of the ConnectionSuccess event for the MQTT5 client. */ export interface ConnectionSuccessEvent { /** * CONNACK packet received from the server. */ connack: mqtt5_packet.ConnackPacket; /** * Final MQTT5 connection settings negotiated with the server. */ settings: NegotiatedSettings; } /** * Payload of the ConnectionFailure event for the MQTT5 client. */ export interface ConnectionFailureEvent { /** * Description of why the connection attempt failed. */ error: ICrtError; /** * If the connection failure was indicated by the server's CONNACK response, the CONNACK packet received from * the server. */ connack?: mqtt5_packet.ConnackPacket; } /** * Payload of the Disconnection event for the MQTT5 client. */ export interface DisconnectionEvent { /** * Best-guess description of why the disconnection occurred. */ error: ICrtError; /** * If the disconnection event was due to a server-side DISCONNECT packet, the DISCONNECT packet received from * the server. */ disconnect?: mqtt5_packet.DisconnectPacket; } /** * Payload of the MessageReceived event for the MQTT5 client. */ export interface MessageReceivedEvent { /** * PUBLISH packet received from the server */ message: mqtt5_packet.PublishPacket; } /** * Client Error event listener signature */ export declare type ErrorEventListener = (error: ICrtError) => void; /** * Client Stopped lifecycle event listener signature */ export declare type StoppedEventListener = (eventData: StoppedEvent) => void; /** * Client AttemptingConnect lifecycle event listener signature */ export declare type AttemptingConnectEventListener = (eventData: AttemptingConnectEvent) => void; /** * Client ConnectionSuccess lifecycle event listener signature */ export declare type ConnectionSuccessEventListener = (eventData: ConnectionSuccessEvent) => void; /** * Client ConnectionFailure lifecycle event listener signature */ export declare type ConnectionFailureEventListener = (eventData: ConnectionFailureEvent) => void; /** * Client Disconnection lifecycle event listener signature */ export declare type DisconnectionEventListener = (eventData: DisconnectionEvent) => void; /** * Message received event listener signature */ export declare type MessageReceivedEventListener = (eventData: MessageReceivedEvent) => void; /** * Polymorphic success result for publish actions: * * * QoS 0 - resolves to undefined * * QoS 1 - resolves to a {@link PubackPacket} * * QoS 2 - (not yet supported) would resolve to a Pubcomp or a Pubrec */ export declare type PublishCompletionResult = mqtt5_packet.PubackPacket | undefined; /** * Shared MQTT5 client interface across browser and node. * * Common event manipulation patterns have explicit functions separate from the EventListener interface because * creating an abstract event listening interface in typescript eludes me. */ export interface IMqtt5Client { /** * Triggers cleanup of native resources associated with the MQTT5 client. Once this has been invoked, callbacks * and events are not guaranteed to be received. * * On the browser, the implementation is an empty function. * * On Node, this must be called when finished with a client; otherwise, native resources will leak. It is not safe * to invoke any further operations on the client after close() has been called. * * For a running client, safe and proper shutdown can be accomplished by * * ```ts * const stopped = once(client, "stopped"); * client.stop(); * await stopped; * client.close(); * ``` * * This is an asynchronous operation. */ close(): void; /** * Notifies the MQTT5 client that you want it to maintain connectivity to the configured endpoint. * The client will attempt to stay connected using the properties of the reconnect-related parameters * in the mqtt5 client configuration. * * This is an asynchronous operation. */ start(): void; /** * Notifies the MQTT5 client that you want it to end connectivity to the configured endpoint, disconnecting any * existing connection and halting reconnection attempts. * * This is an asynchronous operation. Once the process completes, no further events will be emitted until the client * has {@link start} invoked. * * @param disconnectPacket (optional) properties of a DISCONNECT packet to send as part of the shutdown process */ stop(packet?: mqtt5_packet.DisconnectPacket): void; /** * Subscribe to one or more topic filters by queuing a SUBSCRIBE packet to be sent to the server. * * @param packet SUBSCRIBE packet to send to the server * @returns a promise that will be rejected with an error or resolved with the SUBACK response */ subscribe(packet: mqtt5_packet.SubscribePacket): Promise<mqtt5_packet.SubackPacket>; /** * Unsubscribe from one or more topic filters by queuing an UNSUBSCRIBE packet to be sent to the server. * * @param packet UNSUBSCRIBE packet to send to the server * @returns a promise that will be rejected with an error or resolved with the UNSUBACK response */ unsubscribe(packet: mqtt5_packet.UnsubscribePacket): Promise<mqtt5_packet.UnsubackPacket>; /** * Send a message to subscribing clients by queuing a PUBLISH packet to be sent to the server. * * @param packet PUBLISH packet to send to the server * @returns a promise that will be rejected with an error or resolved with the PUBACK response */ publish(packet: mqtt5_packet.PublishPacket): Promise<PublishCompletionResult>; }