Mod_proxy server flow for making HTTP requests via a hosted javascript app

Figured it out after a bit of trial and error. Here's what I have...

1. Can I achieve this on one server using one IP address or do one server to host and one to mod_proxy with?
   A: ON server with one IP address works just fine. All proxy functions are handled via a port which in my case is :9000. The choice of port number is really up to you. 9000 was just a high number and didn't conflict with any other node functions. It also seems to be a unwritten standard from what I can tell.

2. If I can do this on one server. If so, what is the generic setup (A to B)? One or two virtual hosts?
   A: This is probably best explained by just looking at my Apache virtual host setup...
   
   Since i'm using SSL, all port :80 HTTP requests are rewritten to HTTPS

    VirtualHost *:80
      RewriteEngine On
      RewriteCond %{HTTPS} off
      RewriteRule (.*) http(s)://%{HTTP_HOST}%{REQUEST_URI}
    /VirtualHost

I'm running a node app on port :3000 so all traffic is routed from the standard :443 to port :3000 and visa versa. Basically port :3000 becomes the primary domain name via a server proxy as far as the public is concerned.

    VirtualHost *:443
      RewriteEngine On
      ProxyRequests Off
      SSLEngine on
      SSLProxyEngine on

      SSLCertificateFile /pathToCert/sslCert.crt
      SSLCertificateKeyFile /pathToKey/sslKey.key

      Location /
          ProxyPass http://localhost:3000/ 
          ProxyPassReverse http://localhost:3000/
      /Location

    /VirtualHost

I've assigned port :9000 as the reverse proxy for my Cross Domain HTTP POST requests. The ProxyPass and ProxyPassReverse directives essentially rewrite the url of HTTP requests I make with an address of my domain.

https://MySite.com:9000/?request&params&here

will become

https://SomeOtherSiteThanMine.com/?request&params&here

Thus fooling the browser into thinking I'm making requests to my own domain. Also notice the "Header set" lines which make the requests CORS compatible with my proxy.

    VirtualHost *:9000
      RewriteEngine On
      ProxyRequests Off

      SSLEngine on
      SSLProxyEngine on

      SSLCertificateFile /pathToCert/sslCert.crt
      SSLCertificateKeyFile /pathToKey/sslKey.key

      ProxyPass / https://SomeOtherSiteThanMine.com/
      ProxyPassReverse / https://SomeOtherSiteThanMine.com/

      Header set Access-Control-Allow-Origin "*"
      Header set Access-Control-Allow-Methods "POST"
    /VirtualHost

3. Explain the ProxyPass and ProxyReversePass directives. Do I need to add my outside service URL here?
A: See above


4. Am I just going the complete wrong way down a one way street?
A: Nope, ended up working out perfectly.


If anyone sees a problem with the method, by all means chime in. I just pieced together a a handful of vaguely described examples.