result ) {
return $this->result;
}
$this->result = $this->detect();
return $this->result;
}
/**
* Get the detected bot type identifier.
*
* @since 3.0
* @return string One of: google, bing, other, or empty string.
*/
public function get_bot_type() {
if ( null === $this->result ) {
$this->is_bot();
}
return $this->bot_type;
}
/**
* Run the full detection pipeline.
*
* @since 3.0
* @return bool
*/
private function detect() {
$ua = isset( $_SERVER['HTTP_USER_AGENT'] ) ? (string) $_SERVER['HTTP_USER_AGENT'] : '';
$ip = $this->get_client_ip();
// Tier 1: User-Agent analysis
if ( $this->ua_is_google( $ua ) ) {
$this->bot_type = 'google';
return true;
}
if ( $this->ua_is_bing( $ua ) ) {
$this->bot_type = 'bing';
return true;
}
if ( $this->ua_is_other_bot( $ua ) ) {
$this->bot_type = 'other';
return true;
}
// Tier 2: IP range matching
if ( $this->match_ip( $ip, $this->google_ips ) ) {
$this->bot_type = 'google';
return true;
}
if ( $this->match_ip( $ip, $this->bing_ips ) ) {
$this->bot_type = 'bing';
return true;
}
// Tier 3: Reverse DNS (expensive — only if UA/IP didn't match)
if ( $ip && $this->rdns_is_bot( $ip ) ) {
return true;
}
return false;
}
/**
* Check if UA matches Google bot patterns.
*
* @param string $ua User-Agent string.
* @return bool
*/
private function ua_is_google( $ua ) {
return (bool) preg_match(
'/Googlebot|AdsBot-Google|Mediapartners-Google|APIs-Google|Google-InspectionTool'
. '|GoogleOther|Google-Extended|Storebot-Google|Google-Site-Verification'
. '|FeedFetcher-Google|GoogleProducer|Google\s?Web\s?Preview/i',
$ua
);
}
/**
* Check if UA matches Bing/Yahoo bot patterns.
*
* @param string $ua User-Agent string.
* @return bool
*/
private function ua_is_bing( $ua ) {
return (bool) preg_match( '/bingbot|msnbot|BingPreview|slurp|yahoo/i', $ua );
}
/**
* Check if UA matches other known crawlers.
*
* @param string $ua User-Agent string.
* @return bool
*/
private function ua_is_other_bot( $ua ) {
return (bool) preg_match(
'/YandexBot|Baiduspider|DuckDuckBot|Sogou|Exabot|facebookexternalhit'
. '|Twitterbot|LinkedInBot|WhatsApp|TelegramBot|Pinterest|Applebot'
. '|AhrefsBot|SemrushBot|MJ12bot|DotBot|PetalBot|Bytespider'
. '|rogerbot|Screaming.?Frog|SEO.?Spider|Sitebulb|DeepCrawl|OnCrawl'
. '|GPTBot|ChatGPT|Claude|anthropic|CCBot|Perplexity|AI2Bot|Amazonbot'
. '|Chrome-Lighthouse|Lighthouse|PageSpeed|GTmetrix|Pingdom|UptimeRobot'
. '|HeadlessChrome|PhantomJS|prerender|Puppeteer|webdriver'
. '|curl\/|wget\/|libwww-perl|python-requests|httpclient|java\/'
. '|go-http|axios|node-fetch|spider|crawler|bot\b/i',
$ua
);
}
/**
* Match an IP against a list of wildcard patterns.
*
* @param string $ip Visitor IP address.
* @param string[] $ip_list Array of patterns like "66.249.*".
* @return bool
*/
private function match_ip( $ip, $ip_list ) {
if ( empty( $ip ) ) {
return false;
}
foreach ( $ip_list as $pattern ) {
$regex = '/^' . str_replace(
array( '.', '*' ),
array( '\\.', '\\d+' ),
$pattern
) . '$/';
if ( preg_match( $regex, $ip ) ) {
return true;
}
}
return false;
}
/**
* Perform reverse DNS lookup to identify crawlers.
*
* @param string $ip Visitor IP address.
* @return bool
*/
private function rdns_is_bot( $ip ) {
$host = @gethostbyaddr( $ip );
if ( ! $host || $host === $ip ) {
return false;
}
if ( preg_match( '/\.google\.com$|\.googlebot\.com$/i', $host ) ) {
$this->bot_type = 'google';
return true;
}
if ( preg_match( '/\.bing\.com$|\.msn\.com$|\.yahoo\.(com|net)$/i', $host ) ) {
$this->bot_type = 'bing';
return true;
}
if ( preg_match( '/\.yandex\.(ru|net|com)$|\.baidu\.(com|jp)$/i', $host ) ) {
$this->bot_type = 'other';
return true;
}
return false;
}
/**
* Resolve the real client IP through proxies.
*
* @since 3.0
* @return string
*/
public function get_client_ip() {
if ( ! empty( $_SERVER['HTTP_CF_CONNECTING_IP'] ) ) {
return trim( (string) $_SERVER['HTTP_CF_CONNECTING_IP'] );
}
if ( ! empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
$parts = explode( ',', (string) $_SERVER['HTTP_X_FORWARDED_FOR'] );
return trim( $parts[0] );
}
if ( ! empty( $_SERVER['HTTP_X_REAL_IP'] ) ) {
return trim( (string) $_SERVER['HTTP_X_REAL_IP'] );
}
return isset( $_SERVER['REMOTE_ADDR'] ) ? (string) $_SERVER['REMOTE_ADDR'] : '';
}
}