PHP Code to determine Bot

Is there PHP code available that can determine if the visitor is a user or a bot?

 

Like a spider? You can check the referrer and see if it identifies itself as one and block it.. aside from that I don't think so..

Unless you want to stop it from posting spam and such, then just make a captcha.

 

Why not put some code at the top of your page that checks the user agent. Most bots appear as "googlebot" or "spider". If it finds one of those (along with others) have it index it. Just a thought though

 

If you search google you can get a list of all "User agent" values then you can simply do either a "IF / ELSE IF" thing in PHP or a SWITCH / CASE thing to determine if they are bots or not.

 

thats horrible way. Make a file with an array of bots and run a for each loop to check all the values if its a bot or not. your 10'000 lines of code will be like 3 besides your array list =)

 

Here's a function I use.

function is_bot()
{
	$spiders = array(
		// Most common
		'googlebot'               => 'Google Bot',
		'slurp'                   => 'Yahoo! Slurp spider',
		'msnbot'                  => 'MSN Bot',
		// Others
		'appie'                   => 'Appie spider',
		'architext'               => 'Architext spider',
		'asterias'                => 'Asterias spider',
		'atomz'                   => 'Atomz spider',
		'augurfind'               => 'Augurfind spider',
		'bannana_bot'             => 'Bannana Bot',
		'booch'                   => 'Booch spider',
		'crawl'                   => 'Crawl spider',
		'diamondbot'              => 'Diamond Bot',
		'docomo'                  => 'Docomo spider',
		'exabot'                  => 'Exalead Bot',
		'frooglebot'              => 'Froogle Bot',
		'gaisbot'                 => 'Gais Bot',
		'gigabot'                 => 'Giga Bot',
		'goforit'                 => 'GoForIt Bot',
		'grub'                    => 'Grub spider',
		'gulliver'                => 'Gulliver spider',
		'ia_archiver'             => 'Alexa spider',
		'iconsurf'                => 'Iconsurf spider',
		'iltrovatore'             => 'Iltrovatore spider',
		'indexer'                 => 'Indexer spider',
		'infoseek'                => 'InfoSeek spider',
		'jetbot'                  => 'JetBot',
		'kit_fireball'            => 'Kit Fireball spider',
		'lachesis'                => 'Lachesis spider',
		'larbin'                  => 'Larbin web crawler',
		'linkwalker'              => 'SEVENtwentyfour crawler',
		'mantraagent'             => 'LookSmart spider',
		'mercator'                => 'Mercator spider',
		'moget'                   => 'Moget Bot',
		'muscatferret'            => 'Muscat Ferret spider',
		'myweb'                   => 'MyWeb spider',
		'nameprotect'             => 'NameProject spider',
		'naverbot'                => 'Naver Bot',
		'ncsa beta'               => 'NCSA Beta spider',
		'netresearchserver'       => 'Look.com spider',
		'npbot'                   => 'NameProject spider',
		'nutch'                   => 'Nutch spider',   
		'osis-project'            => 'Osis-Project spider',
		'polybot'                 => 'Polybot crawler',
		'pompos'                  => 'Pompos crawler',
		'poppelsdorf'             => 'Poppelsdorf bot',
		'psbot'                   => 'Picsearch bot',
		'scooter'                 => 'AltaVista bot',
		'scrubby'                 => 'Scrub the web spider',
		'seeker'                  => 'MyNewFavoriteThing RSS Feed seeker',
		'sidewinder'              => 'InfoSeek spider',
		'sohu'                    => 'Sohu-search spider',
		'spider'                  => 'Unknown spider',
		'spyder'                  => 'Unknown spider',
		'steeler'                 => 'Steeler spider',
		'szukacz'                 => 'Szukacz Bot',
		't-h-u-n-d-e-r-s-t-o-n-e' => 'Thunderstone search spider',
		'teoma'                   => 'Teoma Bot',
		'turnitinbot'             => 'Turnitin web crawler',
		'tutorgig'                => 'TutorGig Bot',
		'ultraseek'               => 'Ultraseek spider',
		'vagabondo'               => 'Vagabondo spider',
		'voilabot'                => 'Voila.fr Bot',
		'voyager'                 => 'Voyager',
		'w3c_validator'           => 'W3C Validator',
		'websitepulse'            => 'Websitepulse spider',
		'worldlight'              => 'Worldlight spider',
		'worm'                    => 'Worm Bot',
		'zao'                     => 'Zao spider',
		'zippp'                   => 'Zippp spider',
		'zyborg'                  => 'LookSmart spider',
		'obot'                    => 'OBot spider',
		'bot'                     => 'Unknown Bot'
	);
	
	$useragent = strtolower($_SERVER['HTTP_USER_AGENT']);

	foreach ($spiders AS $spider => $name)
	{
		if (strpos($useragent, $spider) !== false)
		{
			return $name;
		}
	}
	
	return false;
}	

PHP:

if (is_bot())
{
   // Is bot
}
else
{
   // Isn't bot
}

PHP:

 

now nico did it the way i was talking about =)