how to properly mod_rewrite - debugging

Question

I am using apache2 + tomcat on ubuntu 10.4. I am running on tomcat server that has webapps listening on 8080
"http://internal:8080/dir/name-privatewebapp/"
"http://internal:8080/dir/name-publicwebapp/"
External facing Apache server is proxying requests for the domain.
I would like to remap "subdomain" to "domain.com/subdomain" , so any other requests would be proxied to the appropriate path / webapp
web.john-doe.domain.com ---> www.domain.com/web/john-doe
http://www.john-doe.com ---> www.domain.com/web/john-doe
http://www.foo-bar.com ---> www.domain.com/web/foo-bar
I couldnt make it work with mod_rewrite alone. I have been looking into
mod_proxy, mod_proxy_ajp, and mod_rewrite
I would like the server to
Grab the subdomain from the domain
Make sure the subdomain is not www, w or ww
Check if the directory actually exists on "www.domain.com" before rewrite
if the directory doesnt exist it stays as wild domain
Finally, if the directory exist the actual rewrite
I checked several links and studied tutorials on http://www.askapache.com/htaccess/crazy-advanced-mod_rewrite-tutorial.html
It is without success.
I followed this
illumin-it.servehttp.com/wordpress/2012/01/redirecting-to-as-using-apache/
with a bit of success.
However, I would like to the server to do it on the fly through rewrites and proxies without editing the vhost for every subdomain.
here is my updated vhost file
<VirtualHost *:80>
ServerAdmin webmaster#localhost
ServerName www.domain.com
ServerAlias www.domain.com domain.com *.domain.com
RedirectPermanent / http://www.domain.com
DocumentRoot /var/www
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
<Directory /var/www/>
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
<IfModule mod_rewrite.c>
Options +FollowSymLinks
Options +Indexes
RewriteEngine On
RewriteBase /
# Prevent looping this rule
# RewriteCond %{ENV:REDIRECT_STATUS} !200
# RewriteCond %{HTTP_HOST} !www.domain.com$ [NC]
# RewriteCond %{HTTP_HOST} ^(www\.)?([a-z0-9.-]+).domain.com$ [NC]
# RewriteRule (.*) /%2/$1 [L]
# change the "." in the path to "/"
# RewriteRule ^(.*)\.(.*)/(.*)$ /$1/$2/$3 [L]
#redirect domain.com to www.domain.com
RewriteCond %{HTTP_HOST} !^domain\.com$ [NC]
RewriteRule ^ http://www.domain.com%{REQUEST_URI} [R=301,NC]
</IfModule>
</Directory>
ScriptAlias /cgi-bin/ /usr/lib/cgi-bin/
<Directory "/usr/lib/cgi-bin">
AllowOverride None
Options +ExecCGI -MultiViews +SymLinksIfOwnerMatch
Order allow,deny
Allow from all
</Directory>
ErrorLog /var/log/apache2/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /var/log/apache2/access.log combined
Alias /doc/ "/usr/share/doc/"
<Directory "/usr/share/doc/">
Options Indexes MultiViews FollowSymLinks
AllowOverride None
Order deny,allow
Deny from all
Allow from 127.0.0.0/255.0.0.0 ::1/128
</Directory>
<Proxy *>
Order deny,allow
Allow from all
</Proxy>
# ErrorLog /var/log/apache2/webapp_error.log
# LogLevel warn
# CustomLog /var/log/apache2/webapp_access.log combined
ProxyPass / ajp://localhost:8009/
ProxyPassReverse / ajp://localhost:8009/
# ProxyPass /user/ http://localhost:8080/user/privatewebapp/
# ProxyPassReverse /user/ http://localhost:8080/user/privatewebapp/
#
# ProxyPass /publicweb/ http://localhost:8080/dir/publicwebapp/
# ProxyPassReverse /publicweb/ http://localhost:8080/dir/publicwebapp/
#
# ProxyPass / http://localhost:8080/dir/publicwebapp/
# ProxyPassReverse / http://localhost:8080/dir/publicwebapp/
ServerName www.domain2.com
ProxyRequests Off
ProxyPreserveHost On
RewriteEngine On
RewriteCond %{HTTP_HOST} ^dir/publicwebapp$ [NC]
RewriteRule ^(.*)$ http://www.domain2.com/$1 [R=301,L]
<Location / >
Order deny,allow
Allow from all
RedirectMatch ^/$ /dir/publicwebapp/
ProxyPass ajp://localhost:8009/
ProxyPassReverse ajp://localhost:8009/
</Location>
</VirtualHost>
I also tried...
http://httpd.apache.org/docs/2.0/rewrite/rewrite_guide.html
assuming www.username.host.com/anypath internally maps to www.host.com/home/username/anypath
As the site's applications created with Java servers, I believe mod_rewrite alone doesnt work.
Virtual User Hosts
RewriteCond %{HTTP_HOST} ^www\.[^.]+\.host\.com$
RewriteRule ^(.+) %{HTTP_HOST}$1 [C]
RewriteRule ^www\.([^.]+)\.host\.com(.*) /home/$1$2

Answer 1

Your first set of rules:
#redirect domain.com to www.domain.com
RewriteCond %{HTTP_HOST} !^www\.domain\.com$ [NC]
RewriteRule .+ http://www.domain.com%{REQUEST_URI} [R=301,NC]
Is superceding any subdomain you have if you don't have an empty request. The second set of rules comes close to what you want. But they loop and they don't turn multiple subdomain entries into directory paths, so try putting this set of rules first:
# Prevent looping this rule
RewriteCond %{ENV:REDIRECT_STATUS} !200
RewriteCond %{HTTP_HOST} !www.domain.com$ [NC]
RewriteCond %{HTTP_HOST} ^(www\.)?([a-z0-9.-]+).domain.com$ [NC]
RewriteRule (.*) /%2/$1 [L]
# change the "." in the path to "/"
RewriteRule ^(.*)\.(.*)/(.*)$ /$1/$2/$3 [L]
Then change your "non-www to www" rule to this (and place after the above rules):
#redirect domain.com to www.domain.com
RewriteCond %{HTTP_HOST} !^domain\.com$ [NC]
RewriteRule ^ http://www.domain.com%{REQUEST_URI} [R=301,NC]

Answer 2

In similar cases I usualy put somethin like this to .htaccess in webroot (/var/www/.htaccess):
<IfModule mod_rewrite.c>
RewriteEngine on
RewriteCond %{HTTP_HOST} subdomain1.domain.com
RewriteCond %{REQUEST_URI} !^/subdomain1
RewriteRule ^(.*)$ one/$1 [L]
RewriteCond %{HTTP_HOST} subdomain2.domain.com
RewriteCond %{REQUEST_URI} !^/subdomain2
RewriteRule ^(.*)$ two/$1 [L]
RewriteRule ^$ / [L]
RewriteRule (.*) /$1 [L]
</IfModule>
so I have
subdomain1.servername.com -> /var/www/subdomain1
subdomain2.servername.com -> /var/www/subdomain2
servername.com -> /var/www
Maybe this will help you?