How to add campaign tracking data to any url automatically? - url

Question

I get a bunch of different URL from my sources and what I would like is to redirect to the same URL, but with campaign data added to URL (to track the referred clicks).
For example I have these URLs:
www.example.com/category/product/name.html
www.example.com/id_product=5
I want to add at the end the following: utm_source=SOURCE&utm_medium=MEDIUM&utm_campaign=CAMPAIGN
And the URLs to become
www.example.com/category/product/name.html?utm_source=SOURCE&utm_medium=MEDIUM&utm_campaign=CAMPAIGN
www.example.com/id_product=5&utm_source=SOURCE&utm_medium=MEDIUM&utm_campaign=CAMPAIGN
How to I correctly check and cover all the cases if a URL string has parameters, and add mine?
I want to do it in node.js
Thank you

Answer 1

Elaborating on #snkashis, a similar but arguably more elegant solution, again using node's url module, is:
var addQueryParams = function (cleanUrl) {
var obj = url.parse(cleanUrl, true, false);
obj.query['utm_source'] = 'SOURCE';
obj.query['utm_medium'] = 'MEDIUM';
obj.query['utm_campaign'] = 'CAMPAIGN';
delete obj.search; // this makes format compose the search string out of the query object
var trackedUrl = url.format(obj);
return trackedUrl;
};
This works, because url.format first looks for search and, if it can't find it, it composes the query string from the query object
(taken from node url module documentation http://nodejs.org/api/url.html#url_url_format_urlobj )
search will be used in place of query
query (object; see querystring) will only be used if search is absent.

Answer 2

Here is a example showing different scenarios using Node's URL module.
var url = require('url');
var exurls = ["www.example.com/category/product/name.html","www.example.com/id_product=5?hasparam=yes"]
var to_append = "utm_source=SOURCE&utm_medium=MEDIUM&utm_campaign=CAMPAIGN";
for (i=0;i<exurls.length;i++) {
var parsedobj = url.parse(exurls[i],true,false);
//Below checks if param obj is empty.
if (Object.keys(parsedobj.query).length!==0) {
var newpath = parsedobj.href+"&"+to_append;
}
else {
var newpath = parsedobj.href+"?"+to_append;
}
console.log(newpath);
}

Answer 3

Connect will help you:
var connect = require('connect');
var app = connect();
app.use(connect.query());
app.use(function (req, res, next) {
console.log(req.query);
res.end(JSON.stringify(req.query));
});
app.listen(3000);