Nginx rewrite non-www-prefixed domain to www-prefixed domain

user_101911 0
Viewed 50979

I see the Nginx HttpRewriteModule documentation has an example to rewrite a www-prefixed domain to a non-www-prefixed domain:

if ($host ~* www\.(.*)) {
  set $host_without_www $1;
  rewrite ^(.*)$ http://$host_without_www$1 permanent; # $1 contains '/foo', not 'www.mydomain.com/foo'
}

How can I do the reverse-- rewrite a non-www-prefixed domain to a www-prefixed domain? I thought maybe I could do something like the following but Nginx doesn't like the nested if statement.

if ($host !~* ^www\.) {                       # check if host doesn't start with www.
    if ($host ~* ([a-z0-9]+\.[a-z0-9]+)) {    # check host is of the form xxx.xxx (i.e. no subdomain)
        set $host_with_www www.$1;
        rewrite ^(.*)$ http://$host_with_www$1 permanent;
    }
}

Also I wanted this to work for any domain name without explicitly telling Nginx to rewrite domain1.com -> www.domain1.com, domain2.com -> www.domain2.com, etc. since I have a large number of domains to rewrite.

url-rewriting nginx rewrite
7 Answers

HTTP & HTTPS without if conditions:

server {
    listen          80;
    listen          443;
    server_name     website.com;

    return 301 $scheme://www.website.com$request_uri;
}
server {
    listen          80;
    listen          443 default_server ssl;
    server_name     www.website.com;

    # Your config goes here #
}
user_75519330

Solution for multiple domains, working on nginx 1.17 for me:

server {
        listen                                80;
        server_name                           .example.com;

        set $host_with_www                 $host;

        if ($host !~* www\.(.*)) {
            set $host_with_www www.$host;
        }

        return                                301 https://$host_with_www$request_uri;
}

In this config example additionally rewrites HTTP on HTTPS, if you don't want rewrite — replace https:// with http:// in return string.

If you want keep protocol — use $scheme variable.

user_52208260
Related