NoBots

Caddy Server plugin to protect your website against web crawlers and bots.

Usage

The directive for the Caddyfile is really simple. First, you have to place the bomb path next to the nobots keyword, for example bomb.gz in the example below.

Then you can specify user agent either as strings or regular expresions. When using regular expresions you must add the regexp keyword in front of the regex.

Caddyfile example:

nobots "bomb.gz" {
  "Googlebot/2.1 (+http://www.googlebot.com/bot.html)"
  "DuckDuckBot"
  regexp "^[Bb]ot"
  regexp "bingbot"
}

There is another keyword that is useful in case you want to allow crawlers and bots navigate through specific parts of your website. The keyword is public and its values are regular expresions, so you can use it as following:

nobots "bomb.gz" {
  "Googlebot/2.1 (+http://www.googlebot.com/bot.html)"
  public "^/public"
  public "^/[a-z]{,5}/public"
}

The above example will send the bot to all URIs except those that match with /public and [a-z]{,5}/public.

NOTE: By default all URIs.

How to create a bomb

The bomb is not provided within the plugin so you have to create one. In Linux it is really easy, you can use the following commands.

dd if=/dev/zero bs=1M count=1024 | gzip > 1G.gzip
dd if=/dev/zero bs=1M count=10240 | gzip > 10G.gzip
dd if=/dev/zero bs=1M count=1048576 | gzip > 1T.gzip

To optimize the final bomb you may compress the parts several times:

cat 10G.gzip | gzip > 10G.gzipx2
cat 1T.gzip | gzip | gzip | gzip > 1T.gzipx4

NOTE: The extension .gzipx2 or .gzipx4 is only to highlight how many times the file was compressed.