@robot.com/better-mqtt/index.d.cts

A modern, TypeScript-first MQTT client library that provides a better developer experience with async iterators, shared subscriptions, and React hooks. Better MQTT is a wrapper around the excellent [mqtt.js](https://github.com/mqttjs/MQTT.js) library, enh

import { EventEmitter } from 'ee-ts';
import { IClientOptions, ErrorWithReasonCode, MqttClient } from 'mqtt';

interface BetterMQTTMessage<T> {
    topic: string;
    content: T;
    params: string[];
}
/**
 * MQTT subscription options
 */
interface SubscriptionOptions {
    /**
     * MQTT QoS. Default: 2
     */
    qos: 0 | 1 | 2;
    /**
     * MQTT Retain handling. Default: 2
     */
    rh: 0 | 1 | 2;
    /**
     * MQTT Retain as published. Default: false
     */
    rap: boolean;
    /**
     * MQTT No local. Default: false
     */
    nl: boolean;
}

interface SubscriptionEvents<T> {
    message(message: BetterMQTTMessage<T>): void;
    end(): void;
    error(error: Error): void;
}
declare class Subscription<T = string> extends EventEmitter<SubscriptionEvents<T>> {
    private mqtt;
    private generator;
    topic: string;
    /** Subscription options */
    options: SubscriptionOptions;
    parser: (message: Buffer) => T;
    constructor(opts: {
        mqtt: BetterMQTT;
        topic: string;
        parser: (message: Buffer) => T;
        options?: Partial<SubscriptionOptions>;
    });
    handleMessage(message: Buffer<ArrayBufferLike>, topic: string, params: string[]): void;
    [Symbol.asyncIterator](): AsyncGenerator<BetterMQTTMessage<T>>;
    end(): void;
}

/** biome-ignore-all lint/suspicious/noExplicitAny: I'm sure it is fine */

type ConnectArgs = [brokerUrl: string] | [brokerUrl: string, opts?: IClientOptions] | [opts: IClientOptions];
interface BetterMQTTEvents {
    status(status: 'online' | 'offline'): void;
    error(error: Error | ErrorWithReasonCode): void;
    end(): void;
}
type MessageParser<T = string> = (message: Buffer) => T;
declare function stringParser(message: Buffer): string;
declare function jsonParser<T = unknown>(message: Buffer): T;
declare function binaryParser(message: Buffer): Buffer;
declare class BetterMQTT extends EventEmitter<BetterMQTTEvents> {
    readonly client: MqttClient;
    error: Error | ErrorWithReasonCode | null;
    get status(): "online" | "offline";
    private subscriptions;
    constructor(client: MqttClient);
    publish(topic: string, message: string | Buffer, opts?: {
        qos?: 0 | 1 | 2;
        dup?: boolean;
        retain?: boolean;
    }): void;
    publishAsync(topic: string, message: string | Buffer, opts?: {
        qos?: 0 | 1 | 2;
        dup?: boolean;
        retain?: boolean;
    }): Promise<void>;
    publishJson<T>(topic: string, message: T): void;
    publishJsonAsync<T>(topic: string, message: T): Promise<void>;
    unsubscribe(sub: Subscription<unknown>): void;
    subscribe<T>(topic: string, parser: MessageParser<T>, options?: Partial<SubscriptionOptions>): Subscription<T>;
    subscribeString(topic: string, options?: Partial<SubscriptionOptions>): Subscription<string>;
    subscribeJson<T>(topic: string, options?: Partial<SubscriptionOptions>): Subscription<T>;
    subscribeBinary(topic: string, options?: Partial<SubscriptionOptions>): Subscription<Buffer>;
    unsubscribeAsync(sub: Subscription<unknown>): Promise<void>;
    subscribeAsync<T>(topic: string, parser: MessageParser<T>, options?: Partial<SubscriptionOptions>): Promise<Subscription<T>>;
    subscribeStringAsync(topic: string, options?: Partial<SubscriptionOptions>): Promise<Subscription<string>>;
    subscribeJsonAsync<T>(topic: string, options?: Partial<SubscriptionOptions>): Promise<Subscription<T>>;
    subscribeBinaryAsync(topic: string, options?: Partial<SubscriptionOptions>): Promise<Subscription<Buffer>>;
    static connectAsync(...args: ConnectArgs): Promise<BetterMQTT>;
    static connect(...args: ConnectArgs): BetterMQTT;
    end(endClient?: boolean): void;
    endAsync(endClient?: boolean): Promise<void>;
}

export { BetterMQTT, type BetterMQTTEvents, type BetterMQTTMessage, type ConnectArgs, type MessageParser, Subscription, type SubscriptionEvents, type SubscriptionOptions, binaryParser, jsonParser, stringParser };