Proxy a web site and change the content on the fly
Apache can do just about everything with a bit of configuration. I have used HTTP proxying on a number of occasions to make content from one site appear to come from another site. This can be very handy for sites I host at home where I only have one IP address but two servers and want to host different web sites on the same public IP – and all of them on the standard HTTP port.
However, until recently I hadn’t experienced that Apache can also rewrite the content in the actual response. I was faced with the requirement to change all the URIs in the proxied web site so that they pointed to the new URL. When I first searched the net I found the module mod_proxy_html which sounded like the way forward. In the end I didn’t go that route since I found it overly complex and didn’t transform all instances of the links. Instead, the solution was simple and used another Apache module – mod_substitute.
The following virtual host configuration sets up a proxy so that the site www.one.com is proxied to www.two.com. In addition, any occurrences of www.one.com is changed into www.two.com:
<VirtualHost *>
ServerAdmin postmaster@two.com
ServerName www.two.com
<Proxy *>
Order deny,allow
</Proxy>
ProxyRequests on
ProxyPass / http://www.one.com/
ProxyPassReverse / http://www.one.com/
AddOutputFilterByType SUBSTITUTE text/html
Substitute "s|www.one.com|www.two.com|n"
</VirtualHost>
mask IP
When proxying with Apache, it is advisable to use the new version – Apache 2.2 because it’s much improved from the earlier 2.0 version. The new version supports load-balancing as a standard feature and I highly recommend upgrading to the 2.2 version.