redirect to www if there's no subdomain in the url

Question

I have

RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ https://www.%{HTTP_HOST}/$1 [R=301,L]

to redirect to www.mysite.com if www is not in the url. the problem with that is that it will also add www to subdomains for example

test.mysite.com will be changed to www.test.mysite.com

how can I tweak that rule to add www only if there's no subdomain set?

Answer 1

how can I twaek that rule to add www only if there's no subdomain set?

Set condition to make it work for your main domain only:

RewriteCond %{HTTP_HOST} ^[^.]+\.[^.]+$ [NC]
RewriteRule ^ https://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L,NE]

Make sure to test this in a new browser to avoid old cache.

Regex ^[^.]+\\.[^.]+$ will match any domain with a single DOT so it will skip subdomains.