Revisiting Mobile Redirection Using .htaccess ReWrite Rules

Back in 2007 I wrote a post detailing a method for detecting and redirecting mobile browsers using .htaccess. Since then the mobile landscape has changed quite a bit: iPhone and Android have been released, the PDA market is all but dead and phones are better in general.

My original post was based on a PHP script by Andy Moore. It’s worth noting that he has continued to update his script and now has a fancy little generator to help you create a PHP based redirect ruleset. Check out detectmobilebrowsers.mobi for more info.

His solution will probably work for a lot of applications, but there are 2 main reasons I prefer using Apache’s rewrite rules to redirect mobile browsers:
1) Application independent. By putting the rules in the root .htaccess file you can easily redirect traffic across multiple directories, independent of any webapp that might or might not be running in those directories.
2) Faster. Placing the rewrite rules in apache’s httpd.conf file is potentially faster, than running the regexp in a php script for every request.

Enough of that, here’s the updated ruleset.

# don't apply the rules if you're already in the mobile directory, infintine loop
# you'll want to test against the host if you're using a subdomain
RewriteCond %{REQUEST_URI} !^/mobiledirectoryhere/.*$
# if the browser accepts these mime-types, it's definitely mobile, or pretending to be
RewriteCond %{HTTP_ACCEPT} "text\/vnd\.wap\.wml|application\/vnd\.wap\.xhtml\+xml" [NC,OR]
# a bunch of user agent tests
RewriteCond %{HTTP_USER_AGENT} "sony|symbian|nokia|samsung|mobile|windows ce|epoc|opera" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "mini|nitro|j2me|midp-|cldc-|netfront|mot|up\.browser|up\.link|audiovox"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "blackberry|ericsson,|panasonic|philips|sanyo|sharp|sie-"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "portalmmm|blazer|avantgo|danger|palm|series60|palmsource|pocketpc"[NC,OR]
RewriteCond %{HTTP_USER_AGENT} "smartphone|rover|ipaq|au-mic,|alcatel|ericy|vodafone\/|wap1\.|wap2\.|iPhone|android"[NC]
# put your rewrite rules here


Text Version

As you can see, the user agent list is a fair bit less verbose. I’ve been testing the ruleset on a very busy site, based on over 250k mobile site hits this set of rules is causing a lot fewer false positives, while not missing any significant number of mobile browsers.

Linux: Finding Newer Files [OR How To Create A Patch File]

The linux `find` command is very powerful, it has tonnes of switches and options that I’m not terribly familiar with. Even though I’ve been a LAMP developer for over 5 years, I don’t work on the command-line too often. Yesterday I ran into a problem that I had never tried to resolve before. I was working on a large project on a development server and I had some updates I wanted to push to the production server, but I had lost track of which files I had updated. I dug through the find manual for a few minutes and discovered the `-newer` flag, from man “File was modified more recently than file.” With this flag you can generate a list of files that are newer than a given file. If I set file to a file I knew had been updated before my last set of changes, I could pull a list of patch files.

find /path/to/project/ -newer /path/to/project/last-archive.tgz

After some more digging and trial and error I found the proper syntax for rolling up all these files into a nice little patch archive:

tar -czvf patch-20070321.tar `find /path/to/project/ -newer /path/to/project/last-archive.tgz -print`

TinyMy, Quick and Dirty MySQL Shell

Stumbled across a tiny mysql shell – appropriately named ‘tinymy’ – a few months ago.

It’s quite a useful little bit of PHP code. Very lightweight and function interface and shell for MySQL. I use it whenever I need to verify the contents of a database table or test a couple of queries but don’t need a full install phpMyAdmin.

Thought I’d share.
Link

.htaccess Mobile Browser Redirect

UPDATE: New Ruleset Posted – February 2009

I just finished building out a simple little mobile site for hiphopdx.com. When I asked Google the best way to detect mobile browsers with PHP, it led to me this PHP code by Andy Moore. After a few minutes of contemplating the best way to include the code in the existing CMS framework I realized that it would probably be best to move the functionality outside of PHP. I mean, why clutter up display code with HTTP traffic manipulation. The website’s main traffic cop Apache is already perfectly capable of handling the duties already.

Here’s how to redirect mobile traffic using a .htaccess file:

RewriteEngine On
RewriteCond %{REQUEST_URI} !^/m/.*$
RewriteCond %{HTTP_ACCEPT} "text/vnd.wap.wml|application/vnd.wap.xhtml+xml" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "acs|alav|alca|amoi|audi|aste|avan|benq|bird|blac|blaz|brew|cell|cldc|cmd-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "dang|doco|eric|hipt|inno|ipaq|java|jigs|kddi|keji|leno|lg-c|lg-d|lg-g|lge-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT}  "maui|maxo|midp|mits|mmef|mobi|mot-|moto|mwbp|nec-|newt|noki|opwv" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "palm|pana|pant|pdxg|phil|play|pluc|port|prox|qtek|qwap|sage|sams|sany" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "sch-|sec-|send|seri|sgh-|shar|sie-|siem|smal|smar|sony|sph-|symb|t-mo" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "teli|tim-|tosh|tsm-|upg1|upsi|vk-v|voda|w3cs|wap-|wapa|wapi" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "wapp|wapr|webc|winw|winw|xda|xda-" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "up.browser|up.link|windowssce|iemobile|mini|mmp" [NC,OR]
RewriteCond %{HTTP_USER_AGENT} "symbian|midp|wap|phone|pocket|mobile|pda|psp" [NC]
RewriteCond %{HTTP_USER_AGENT} !macintosh [NC] #*SEE NOTE BELOW
RewriteRule ^(.*)$ /m/ [L,R=302]

I did my best to translate the PHP code verbatim, if you want to understand what each line is doing you’ll want to check out the original code. Testing for all those user agents is probably a little overkill, but Mr Moore is a “dotMobi certified mobile web developer” I’m going to assume he knows what he’s talking about.

*The “tosh” user agent (I’m assuming this is for a Toshiba browser?) happens to catch browser on any browser on the Mac OS. I had to add !macintosh to skip macs. The iPhone/iPod Touch does not identify itself as “macintosh.”