isbot

What is isbot?

The 'isbot' npm package is a lightweight utility for detecting bots, crawlers, and spiders based on the user agent string. It helps developers identify non-human traffic to their websites or applications.

What are isbot's main functionalities?

Basic Bot Detection

This feature allows you to check if a given user agent string belongs to a bot. The function returns true if the user agent is identified as a bot, otherwise false.

const isBot = require('isbot');

const userAgent = 'Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)';
console.log(isBot(userAgent)); // true

Custom Bot Patterns

You can extend the default bot detection patterns with custom patterns. This is useful if you have specific bots that are not covered by the default list.

const isBot = require('isbot');

isBot.extend(['my-custom-bot']);
const userAgent = 'my-custom-bot';
console.log(isBot(userAgent)); // true

Bot Detection in HTTP Requests

This feature demonstrates how to use 'isbot' to detect bots in incoming HTTP requests. Depending on whether the user agent is a bot, the server responds with a different message.

const isBot = require('isbot');
const http = require('http');

http.createServer((req, res) => {
  if (isBot(req.headers['user-agent'])) {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.end('Hello, bot!');
  } else {
    res.writeHead(200, { 'Content-Type': 'text/plain' });
    res.end('Hello, human!');
  }
}).listen(3000);

Other packages similar to isbot

useragent

The 'useragent' package provides detailed parsing of user agent strings, including bot detection. It offers more comprehensive information about the user agent, such as browser, version, and OS, but may be more complex to use compared to 'isbot'.

express-useragent

The 'express-useragent' package is an Express middleware for parsing user agent strings. It includes bot detection and provides additional details about the user agent. It is specifically designed for use with Express.js applications.

ua-parser-js

The 'ua-parser-js' package is a JavaScript library for parsing user agent strings. It includes bot detection and provides detailed information about the browser, engine, OS, and device. It is a more general-purpose library compared to 'isbot'.

README

isbot 🤖/👨‍🦰

Detect bots/crawlers/spiders using the user agent string.

Usage

import isbot from 'isbot'

// Nodejs HTTP
isbot(request.getHeader('User-Agent'))

// ExpressJS
isbot(req.get('user-agent'))

// Browser
isbot(navigator.userAgent)

// User Agent string
isbot('Mozilla/5.0 (iPhone; CPU iPhone OS 6_0 like Mac OS X) AppleWebKit/536.26 (KHTML, like Gecko) Version/6.0 Mobile/10A5376e Safari/8536.25 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)') // true
isbot('Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36') // false

Additional functionality

Extend: Add user agent patterns

Add rules to user agent match RegExp: Array of strings

isbot('Mozilla/5.0 (X11) Firefox/111.0') // false
isbot.extend([
    'istat',
    'x11'
])
isbot('Mozilla/5.0 (X11) Firefox/111.0') // true

Exclude: Remove matches of known crawlers

Remove rules to user agent match RegExp (see existing rules in src/list.json file)

isbot('Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4590.2 Safari/537.36 Chrome-Lighthouse') // true
isbot.exclude(['chrome-lighthouse']) // pattern is case insensitive
isbot('Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4590.2 Safari/537.36 Chrome-Lighthouse') // false

Find: Verbose result

Return the respective match for bot user agent rule

isbot.find('Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 DejaClick/2.9.7.2') // 'DejaClick'

Matches: Get patterns

Return all patterns that match the user agent string

isbot.matches('Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SearchRobot/1.0') // ['bot', 'search']

Clear:

Remove all matching patterns so this user agent string will pass

const ua = 'Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SearchRobot/1.0';
isbot(ua) // true
isbot.clear(ua)
isbot(ua) // false

Spawn: Create new instances

Create new instances of isbot. Instance is spawned using spawner's list as base

const one = isbot.spawn()
const two = isbot.spawn()

two.exclude(['chrome-lighthouse'])
one('Chrome-Lighthouse') // true
two('Chrome-Lighthouse') // false

Create isbot using custom list (instead of the maintained list)

const lean = isbot.spawn([ 'bot' ])
lean('Googlebot') // true
lean('Chrome-Lighthouse') // false

Get a copy of the Regular Expression pattern

const { pattern } = isbot

Definitions

• Bot. Autonomous program imitating or replacing some aspect of a human behaviour, performing repetitive tasks much faster than human users could.
• Good bot. Automated programs who visit websites in order to collect useful information. Web crawlers, site scrapers, stress testers, preview builders and other programs are welcomed on most websites because they serve purposes of mutual benefits.
• Bad bot. Programs which are designed to perform malicious actions, ultimately hurting businesses. Testing credential databases, DDoS attacks, spam bots.

Clarifications

What does "isbot" do?

This package aims to identify "Good bots". Those who voluntarily identify themselves by setting a unique, preferably descriptive, user agent, usually by setting a dedicated request header.

What doesn't "isbot" do?

It does not try to recognise malicious bots or programs disguising themselves as real users.

Why would I want to identify good bots?

Recognising good bots such as web crawlers is useful for multiple purposes. Although it is not recommended to serve different content to web crawlers like Googlebot, you can still elect to

• Flag pageviews to consider with business analysis.
• Prefer to serve cached content and relieve service load.
• Omit third party solutions' code (tags, pixels) and reduce costs.

It is not recommended to whitelist requests for any reason based on user agent header only. Instead other methods of identification can be added such as reverse dns lookup.

Data sources

We use external data sources on top of our own lists to keep up to date

Crawlers user agents:

• user-agents.net
• crawler-user-agents repo
• myip.ms
• matomo.org
• A Manual list

Non bot user agents:

• user-agents npm package
• A Manual list

Missing something? Please open an issue

Major releases breaking changes (full changelog)

Version 3

Remove testing for node 6 and 8

Version 2

Change return value for isbot: true instead of matched string

Version 1

No functional change

Real world data

Execution times in milliseconds

Changelog

3.6.8

• Add Speedcurve: Maximilian Haupt
• Exclude specific "client" substrings