Exclude your staging site from Google with robots.txt and not shoot yourself in the foot

If you want to exclude your staging site from Google using robots.txt without running the risk to forget deleting the file once you go live, name the file robots.exclude.txt instead.

In your Apache Vhost config, rewrite requests for the staging server only:

CopyRewriteEngine On
RewriteCond %{HTTP_HOST} ^staging\.project\.com$
RewriteRule ^robots\.txt$ /robots.exclude.txt

Your robots.exclude.txt looks like this:

Copy# This file is returned for /robots.txt on staging servers
User-agent: *
Disallow: /

Important Note: If your setup is incorrect and /robots.txt is not accessible, it means there is no protection at all!