crawler4j
Crawler4j Java web crawler framework
About this crawler
crawler4j is a web crawler identified by the regular-expression pattern crawler4j in the User-Agent request header. It is categorised as http-library. Use the regex above to detect, log, allow, or block crawler4j traffic in your web server, CDN edge rules, or robots.txt.
Block-rate · top 25k sites
0.59%
Technical details
- Name
- crawler4j
- Pattern
crawler4j- Tags
- http-library
- Reference
- https://github.com/yasserg/crawler4j
- Added
- 2015/05/07
- Instances
- 2 known sample(s)
Sample User-Agent strings
crawler4j (http://code.google.com/p/crawler4j/)
crawler4j (https://github.com/yasserg/crawler4j/)
Block this crawler
robots.txt — disallow crawler4j:
User-agent: crawler4j
Disallow: /
Apache .htaccess — return 403:
RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} crawler4j [NC]
RewriteRule .* - [F,L]
Nginx — return 403 inside a server block:
if ($http_user_agent ~* "crawler4j") {
return 403;
}
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