带变量的Nginx重写规则

Question

I would like to send all request that came from a sub-domain to index.php and send subdomain name as a $sub

for example:

sub1.mydomain.com
send the above request to:
/var/www/mydomain/index.php?sub=sub1

what I've tried:

rewrite ^(\w+).mydomain.com /index.php?sub=$1 last;
root /var/www/mydomain/;

Answer 1

Rewrites are done in the request URI. This does not contain the host name. Assign the variable sub a default, then using an id statement capture the subdomain replacing the default. Then use an unconditional rewrite.

$sub=www;
if($host ~ ^(\w+\.example.com$) {
    $sub = $1;
}
rewrite ^.*$ /index.php?sub=$sub$args;

From the top of my head. Tweak it using the relevant documentation.