Downtime Detector

Simple module that allows you to easily monitor websites, and create a status page.

Still a work in progress and not ready for prod. Check back soon!

Getting started

Instalation

With npm :

npm install downtime-detector

With yarn :

yarn add downtime-detector

Usage

Import the module :

CommonJS syntax :

const { DownDetector } = require("downtime-detector");

Module ES syntax :

import { DownDetector } from "downtime-detector";

Create a new DownDetector with an URL (string) as a parameter :

const Monitor = new DownDetector("https://website-example.com", options);

Options

Object

PARAMETER	TYPE	OPTIONAL	DEFAULT	DESCRIPTION
interval	number	✓	3000ms	Interval for check site
retries	number	✓	3	Retries before create an outage
timeout	number	✓	3000ms	Maximum waiting time before creating an outage
headers	{ [key: string]: string } | undefined	✓	undefined	Additional headers to be attached to requests

Events

---

up

Emitted when site is online

Parameter : status

PROPERTIES	TYPE	DESCRIPTION
statusCode	number	The response status code
statusText	string	The response status text
url	string	The url of website
ping	number	The ping latency (in ms)
Uptime	number	Availability time (in ms)

outage

Emitted when site is have an outage

Parameter : status

PROPERTIES	TYPE	DESCRIPTION
statusCode	number	The response status code
statusText	string	The response status text
url	string	The url of website
ping	number	The ping latency (in ms)
unavailability	number	Unavailability time (in ms)

error

Emitted when an error occurred

Parameter : error

Properties

---

available

Return true if site is available else return false

Return :

Boolean

ping

Return the last ping (in ms) or null if it doesn't exist

Return :

Number or Null

uptime

Return the uptime (in ms) or null if it doesn't exist

Return :

Number or Null

unavailability

Return the unavailability or null if it doesn't exist

Return :

Number or Null

Methods

---

start()

Start the monitoring of website

Return :

Boolean

Monitor.start();

restart()

Restart the monitoring of website

Return :

Boolean

Monitor.restart();

stop()

Stop the monitoring of website

Return :

Boolean

Monitor.stop();

setInterval(newInterval)

Change the interval check

Params :

newInterval : The new interval in ms (number)

Return :

Boolean

Monitor.setInterval(200);

setURL(newURL)

Change the ping endpoint

Params :

newURL : The new url (string).

Return :

Boolean

Monitor.setURL("https://www.exempla-website.com");

Example

const { DownDetector } = require("downtime-detector");

const Monitor = new DownDetector("https://website-example.com", {
  interval: 3000,
  timeout: 5000,
});

Monitor.start();
console.log(Monitor.infos);

Monitor.on("outage", (outage) => {
  console.log(outage);
});

Monitor.on("up", (up) => {
  console.log(up);
});
Monitor.on("error", (error) => {
  console.log(error);
});