@isaac-platform/isaac-integration-sdk/heartbeat.js

A Typescript SDK for integrating with ISAAC

import { EventEmitter } from "events";
export class Heartbeat extends EventEmitter {
    /**
     * Creates ISAAC heartbeat handler.
     * @param isaacConn {ISAACServer} - uses ISAAC request definitions.
     */
    constructor(isaacConn) {
        super();
        this.isaacCore = isaacConn;
        this.beating = false;
        this.status = "uninitialized";
        this.interval = 5000; //Default interval is 5 seconds.
    }
    /**
     * Starts heartbeat process and updates status.
     * @param interval {number} - (optional) override default 5000 ms interval
     */
    start(interval) {
        if (this.beating)
            return; // Only one heartbeat running at a time.
        this.intervalID = setInterval(this.beat.bind(this), interval || this.interval);
        this.beating = true;
        this.updateStatus("starting");
    }
    /**
     * Stops heartbeat process and updates status.
     */
    stop() {
        if (!this.beating)
            return; // Can't stop if not running.
        clearInterval(this.intervalID);
        this.beating = false;
        this.updateStatus("disconnected");
    }
    /**
     * Updates the connection status and emits on a change.
     * @param state {string} - New state to define and announce
     */
    updateStatus(state) {
        if (this.status === state)
            return;
        this.status = state;
        this.emit('heartbeatStatusChange', state);
        console.log(`ISAAC Connection changed: ${state}`);
    }
    /**
     * Makes async heartbeat PUT to ISAAC. Updates status to "connected" or "error" depending on acknowledgement from ISAAC.
     * TODO: Implement ISAAC message bus.
     */
    beat() {
        this.isaacCore.isaacConn.putRequest(`subsystems/${this.isaacCore.isaacConn.subsystemID}/heartbeat`, {}).then((response) => {
            console.log(response);
            this.updateStatus("connected");
        }).catch((error) => {
            console.log(error);
            this.updateStatus("error");
        });
    }
}