Cacher is the code snippet organizer for pro developers

// Kevin Guyer - 2013
// Node.js script to handle server (SharePoint) name changes
//  This is designed to catch the use of old urls and present an infomational page with the new url to the resource
//  Test with this to see URL altering:  http://localhost:8080/hr/foosite/barsite/somelibrary/somedoc.pdf

// Intercept incoming port 80 or 443 (needs to operate on both) - set the port below for flavor you are running
var http = require('http');
var url = require("url");
var server = http.createServer();

server.on('request', function(request, response) {
	var hostname = request.headers.host;
    var newHostname = 'https://yournewfarmpath';  // no trailing slash, set to your new farm/server name and path
    var pathname = url.parse(request.url).pathname;
    var newPathname = pathname;
    var query = url.parse(request.url).query;  // optional, not used yet
	
    // Run match logic on array elements to determine what needs to be displayed
    var aResPath = pathname.split('/');
    
    // Modify path elements as needed with element matching:
    var wasAltered = false;
	if(aResPath.length >=1){
		try{
			if(aResPath[1].toLowerCase() == 'hr'){ aResPath[1] = 'HumanResources'; wasAltered = true; }
			if(aResPath[3].toLowerCase() == 'barsite'){ aResPath[3] = 'NewBarSite'; wasAltered = true; }
			// add others as needed, sites on root starting at index [1]...
		} 
		catch(err) {
			// handle as desired...
		}
		
		if(wasAltered == true){
			console.log("Detected swap string in path, altering output.");
			newPathname = '';
			for(i = 1; i < aResPath.length; i++){
				newPathname = newPathname + '/' + aResPath[i];
			}
		}
	}
    // Build response message
    var payload = '<h2>Oops.</h2><p>The url you attempted to reach (<em>' + hostname +  pathname + '</em>) is no longer valid.</p>';
    // Optional: Build and supply a best bet url    
    payload += '<p>Our best guess for the new url for this resource is <a href="'+ newHostname + newPathname+'">'+ newHostname + newPathname+'</a>.</p>';
    payload += '<p>Please update your favorite or link source to reflect this new address.</p>';

    // Optional step to log the old url hit via a web API (REST) - todo...

    // Build and deliver response    
    response.writeHead(200, {"Content-Type": "text/html"});
    response.write(payload);
    response.end();
});

var port = 8080;  // change this to 80 or 443 as needed
server.listen(port);
server.once('listening', function() {
    console.log('Redirect server is now listening on port %d', port);
});