Using Apache as a reverse‑proxy
Apache includes the ability to function as a reverse proxy, which means it can be directed to delegate certain requests to another server. I've found two useful applications for mod_proxy recently: mirroring static files from production, and accessing JSON data.
Static files on a Drupal development server
If your files directory is large, it may be impractical to replicate it on a development server. Instead, you can ask Apache to proxy requests for any missing files to the production server.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} /sites/default/files
RewriteRule ^(.*)$ http://www.example.com/$1 [P,L]The "P" flag after a RewriteRule creates a proxy, and "L" indicates that processing should stop after this rule. Note this will prevent ImageCache from generating new derivatives on the development site.
Connecting browsers to 3rd-party JSON data
One of the great things about JSON encoding is the data can easily be consumed directly in a browser. You don't need glue code in your application, or (horrors) an SDK. You do however need to deal with the browser's same-origin policy.
On the FontFuse project, we solved this by creating a simple proxy:
RewriteRule (.*serviceapi/webink/.*) http://www.extensis.com/$1 [P,L]
In production, we're using Varnish to allow caching of common requests, but this simple proxy enables development copies of the site to run without additional services.
Comments
I've been using this on our dev environment
http://drupal.org/project/stage_file_proxy
Nice trick with apache though :)
Mon, 03/14/2011 - 23:40
The examples you have posted are for mod_rewrite (which enables you to do url rewriting you have above) instead of mod_proxy and enables you to send off a request to some other service (much like using nginx as a proxy to apache, you use apache as a proxy to nginx or something like tomcat/jetty/whatnot). There is a lot more info at http://httpd.apache.org/docs/2.2/mod/mod_proxy.html and an example at http://confluence.atlassian.com/display/DOC/Using+Apache+with+mod_proxy
Tue, 03/15/2011 - 06:02
Look carefully, under the #rewriteflags section, and you'll see that mod_proxy is indeed invoked by the [P] flag. A RewriteRule is often the easiest way to get at this functionality.
Tue, 03/15/2011 - 06:28
Wow, I feel so silly for missing that. You're absolutely right!
Thu, 05/12/2011 - 19:50
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} /sites/default/files
RewriteRule ^(.*)$ http://www.example.com/$1 [P,L]How can we change that last line so we don't need to hardcode it and make it site-specific in the .htaccess?
Is there a way to pick the domain based on a lookup table based on the original domain or something? That would be epic. Then you it would "just work" for all the sites hosted using a single config + VirtualDocumentRoot.
Fri, 05/13/2011 - 01:08
We use this module to do very similar things. http://drupal.org/project/files_proxy. It's used as a files folder router. Can be setup to 302 if the file is missing or download the file locally. It will also forward the request to a different host on a multisite setup. If it doesn't do what you need it to, let me know! I can probably make it happen. We use this on our default site on production and on all of our dev sites.
Thu, 08/09/2012 - 21:46
Great idea, i was tired of replicating entire codebase+files to development server.
Sat, 03/05/2011 - 07:46