Subdomain https www to non-www - apache

Question

I have a domain called example.com and within this domain are two sub-domains called:
qa1.example.com
qa2.example.com
All of which have SSL certification. However, I have a .htaccess file as follows:
UPDATED
Options +FollowSymlinks
Options -Indexes
<FilesMatch "\.(tpl|ini|log|xml)">
Order deny,allow
Deny from all
</FilesMatch>
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !.*\.(ico|gif|jpg|jpeg|png|js|css)
RewriteRule ^([^?]*) index.php?route=$1 [L,QSA]
RewriteCond %{HTTPS} !=on
RewriteRule %{HTTP_HOST} ^www\.
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
RewriteBase /
RewriteRule ^sitemap.xml$ index.php?route=feed/google_sitemap [L]
RewriteRule ^googlebase.xml$ index.php?route=feed/google_base [L]
RewriteRule ^download/(.*) /index.php?route=error/not_found [L]
The following happens:
http://qa1.example.com > redirects to > https://qa1.example.com
http://www.qa1.example.com > redirects to > https://www.qa1.example.com
https://www.qa1.example.com > redirects to > https://www.qa1.example.com
Number 1 is correct, but numbers 2 and 3 need to redirect to https://qa1.example.com without the www.
How can this be achieved? I can include the .htaccess file separately for the two sub-domains.

Answer 1

RewriteCond %{HTTPS} !=on
RewriteRule ^.*$ https://%{SERVER_NAME}%{REQUEST_URI} [R,L]
Your canonical HTTP to HTTPS and www to non-www redirects should come before your internal rewrites (routing directives). After the RewriteBase directive.
Try the following:
# www to non-www canonicalisation (including subdomains)
RewriteRule %{HTTP_HOST} ^www\.(.*)
RewriteRule ^ https://%1%{REQUEST_URI} [R=301,L]
# HTTP to HTTPS
RewriteCond %{HTTPS} !=on
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [R=301,L]
# Internal rewrites / routing goes here...
If you didn't have additional subdomains it would be relatively trivial to combine these into one rule. Also, this should be a 301 (permanent) redirect, rather than a 302 (temporary), which is what the R flag will default to. (However, it can be easier to test with temporary redirects as they aren't cached by the browser.)
UPDATE: The above directives were assuming these were going in your main domains .htaccess file and the subdomains were all controlled from this (in subdirectories off the main domain's document root). They should still work OK for the subdomains .htaccess file, however, they could be optimised into a single rule (at most one redirect, rather than two). For example:
# www to non-www and HTTP to HTTPS canonicalisation
RewriteCond %{HTTPS} !=on [OR]
RewriteRule %{HTTP_HOST} ^www\.
RewriteRule ^ https://qa1.example.com%{REQUEST_URI} [R=301,L]
The above obviously hardcodes the hostname for the subdomain. If you have only two subdomains then that shouldn't be a problem. It is certainly safer.
To generalise the above, you can use the SERVER_NAME variable. However, you need to ensure that UseCanoncialName On is first set in your server config (default is Off), otherwise this will simply hold the hostname from the request (which is part of the problem you're seeing in your question). The ServerName directive also needs to be set to the correct subdomain. eg. ServerName qa1.example.com.
# www to non-www and HTTP to HTTPS canonicalisation
# UseCanonicalName On - must be set in server config
RewriteCond %{HTTPS} !=on [OR]
RewriteRule %{HTTP_HOST} ^www\.
RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [R=301,L]