htaccess redirect to https://www
If you are using CloudFlare or a similar CDN you will get an infinite loop error with the %{HTTPS} solutions provided here. If you're a CloudFlare user you'll need to use this:
RewriteEngine On
RewriteCond %{HTTP:X-Forwarded-Proto} =http
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
BAD SOLUTION AND WHY!
Don't ever use the solution below because when you are using their code that is something like:
RewriteCond %{HTTPS} off
RewriteRule .* https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule .* https://www.example.com%{REQUEST_URI} [L,R=301]
The browser goes to:
http://example.com
Then redirects to:
https://example.com
Then redirects to:
https://www.example.com
This is too much request to the server.
Most of the answers even accepted one has this problem.
BEST SOLUTION AND THE ANSWER
This code has an [OR] condition to prevent dual changes at url!
RewriteEngine on
RewriteCond %{HTTPS} off [OR]
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule (.*) https://www.example.com%{REQUEST_URI} [R=301,L]
Michals answer worked for me, albeit with one small modification:
Problem:
when you have a single site security certificate, a browser that tries to access your page without https:// www. (or whichever domain your certificate covers) will display an ugly red warning screen before it even gets to receive the redirect to the safe and correct https page.
Solution
First use the redirect to the www (or whichever domain is covered by your certificate) and only then do the https redirect. This will ensure that your users are not confronted with any error because your browser sees a certificate that doesn't cover the current url.
#First rewrite any request to the wrong domain to use the correct one (here www.)
RewriteCond %{HTTP_HOST} !^www\.
RewriteRule ^(.*)$ https://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
#Now, rewrite to HTTPS:
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
To first force HTTPS, you must check the correct environment variable %{HTTPS} off, but your rule above then prepends the www. Since you have a second rule to enforce www., don't use it in the first rule.
RewriteEngine On
RewriteCond %{HTTPS} off
# First rewrite to HTTPS:
# Don't put www. here. If it is already there it will be included, if not
# the subsequent rule will catch it.
RewriteRule .* https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
# Now, rewrite any request to the wrong domain to use www.
# [NC] is a case-insensitive match
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule .* https://www.%{HTTP_HOST}%{REQUEST_URI} [L,R=301]
About proxying
When behind some forms of proxying, whereby the client is connecting via HTTPS to a proxy, load balancer, Passenger application, etc., the %{HTTPS} variable may never be on and cause a rewrite loop. This is because your application is actually receiving plain HTTP traffic even though the client and the proxy/load balancer are using HTTPS. In these cases, check the X-Forwarded-Proto header instead of the %{HTTPS} variable. This answer shows the appropriate process