Problem redirect CodeIgniter URLs to WWW

I have a CI application that uses .htaccess for URL routing. My basic setup is as follow:

RewriteRule ^$ /var/www/html/ferdy/jungledragon/index.php [L]
RewriteCond $1 !^(index\.php|images|img|css|js|swf|type|themes|robots\.txt|favicon\.ico|sitemap\.xml)
RewriteRule ^(.*)$ /var/www/html/ferdy/jungledragon/index.php/$1 [L]

These rules are pretty standard for CI apps. They rewrite all URLs (except for those in the exception list) to the index.php front controller. The lines above also hide index.php, as it would normally appear as part of every URL.

So far, so good. Everything works just fine. Now, for the sake of SEO I would like to force all traffic to www. So I extended the rules as follow:

Options +FollowSymlinks
RewriteEngine on

RewriteRule ^$ /var/www/html/ferdy/jungledragon/index.php [L]
RewriteCond $1 !^(index\.php|images|img|css|js|swf|type|themes|robots\.txt|favicon\.ico|sitemap\.xml)
RewriteRule ^(.*)$ /var/www/html/ferdy/jungledragon/index.php/$1 [L]

rewritecond %{http_host} ^jungledragon.com [nc]
rewriterule ^(.*)$ http://www.jungledragon开发者_如何学编程.com/$1 [r=301,nc]

These last two lines rewrite http://jungledragon.com/anything URLs to http://www.jungledragon.com/anything URLs. This kind of works, but it brings back the index.php part back: http://jungledragon.com/anything becomes http://www.jungledragon.com/index.php/anything.

How exactly do I combine these rules so that they do not interfere with each other? I tried doing the WWW rewrite before the CI rules. That shows an Apache 301 page with an error, rather than doing the actual redirect.

Additionally, I would like to also include rules to get rid of trailing slashes, but for now let's keep the question simple. Note that I did find useful post here and elsewhere yet for some reason I still can't find the correct exact syntax for my situation.

Edit: Thanks for the help. This works:

Options +FollowSymlinks
RewriteEngine on

rewritecond %{http_host} ^jungledragon.com [nc]
rewriterule ^(.*)$ http://www.jungledragon.com/$1 [r=301,nc,L]

RewriteRule ^$ /var/www/html/ferdy/jungledragon/index.php [L]
RewriteCond $1 !^(index\.php|images|img|css|js|swf|type|themes|robots\.txt|favicon\.ico|sitemap\.xml)
RewriteRule ^(.*)$ /var/www/html/ferdy/jungledragon/index.php/$1 [L]

---

mod_rewrite processes rules in a linear fashion. Rules at the top of the file are processed first.

The [nc] and [L] at the end of the rules are the options for how to process rules.

• nc - nocase: case insensative
• L - last: last rule in the execution (if you hit this, stop processing)

You need to put your www redirect rules above your CI rules so it will first add the www, THEN apply the CI rules to the newly re-written url. **And also use either the C or N flag with your www redirect rule so it will parse the next rule.

http://mysite.com/blah ==becomes==> http://www.mysite.com/blah ==becomes==> http://www.mysite.com/index.php/blah (Executed, not redirected)

What's happening currently is:

http://mysite.com/blah ==becomes==> http://mysite.com/index.php/blah (STOP)

Browser goes to http://mysite.com/index.php/blah and a second re-write pass is done since your exceptions stop /index.php urls from being processed

http://mysite.com/index.php/blah ==becomes==> http://www.mysite.com/index.php/blah (Redirected)

---

As Suggested, here is a link to mod_rewrite's documentation if you want to look further.

@LazyOne: Brainfart, sorry.

Here's an excerpt from the docs outlining the flags you'll probably need:

'chain|C' (chained with next rule) This flag chains the current rule with the next rule (which itself can be chained with the following rule, and so on). This has the following effect: if a rule matches, then processing continues as usual - the flag has no effect. If the rule does not match, then all following chained rules are skipped. For instance, it can be used to remove the .www'' part, inside a per-directory rule set, when you let an external redirect happen (where the.www'' part should not occur!).

'next|N' (next round) Re-run the rewriting process (starting again with the first rewriting rule). This time, the URL to match is no longer the original URL, but rather the URL returned by the last rewriting rule. This corresponds to the Perl next command or the continue command in C. Use this flag to restart the rewriting process - to immediately go to the top of the loop. Be careful not to create an infinite loop!

'nocase|NC' (no case) This makes the Pattern case-insensitive, ignoring difference between 'A-Z' and 'a-z' when Pattern is matched against the current URL. 'noescape|NE' (no URI escaping of output) This flag prevents mod_rewrite from applying the usual URI escaping rules to the result of a rewrite. Ordinarily, special characters (such as '%', '$', ';', and so on) will be escaped into their hexcode equivalents ('%25', '%24', and '%3B', respectively); this flag prevents this from happening. This allows percent symbols to appear in the output, as in