No more collisions!

By: Qwaider

On:Tuesday, April 29, 2008 11:23:02 PM
In:Science & Technology
Viewed: (5706) times

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Ahhhh!

Ever since I added the comment RSS capabilities to this blog, I've had a single persistent problem. Name collisions! There are at least 4 people named Khaled, 16 Mona, 25 Rasha, and 3000 Mohammads! So it's completely crazy to differentiate between different users based on name. I gave up on that long time ago. But didn't have a chance to think of a solution!

The only unique thing appears to be the comment owner's email address. BUT there's a HUGE privacy issue there. I CAN'T expose people's emails. Not even for the tiniest of moments! Otherwise everyone will be spammed witless!

... So here's a little trick that saved the day!

What would happen if you generate a GUID (Globally Unique Identity) for every Email? Keep a list in my database that no one has access to and use that instead!

Only my database knows the email associated with every GUID. So that means, the Emails remain hidden from Spam-bots while providing a way for people to reference thier own RSS comments.

And the change is live! You can try it now, just click on the RSS icon next to your name!

For the 3421 people subscribed to user RSS comments, the old collision laden name based RSS is still working, since I didn't want to interrupt the service for anyone.

FAQ:

Why didn't I Use MD5 hash?
For some weird reason, the database MD5 hash was a little different than that generated in the code so it resulted in mismatches.
How secure are GUIDs?
For all practical purposes, they're not that secure. However, since these are unique, randomly generated 36 byte long strings. So the emails are relatively far from the prying eyes of spam bots
Why not Base64 the string to make it shorter
Meh! Either way, they're going to be copied and pasted!
Does this work with FireFox, Opera, Google Reader ...etc?
As far as I know, yes, please report any bugs to me

Enjoy the more secure RSS feeds with GUIDS :)

(I should patent this or something!)

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