Shorter GUIDs than hashing a user id?
- by Alex Mcp
I'm wondering how Instapaper (bookmarklet that saves text) might generate URLs for their bookmarklet.
Mine has a script src of something similar to www.instapaper.com/j/AnJHrfoDTRia
The quality of these URLs is that they need to never collide, and not be really guessable (so other people can't save to your account).
I know a simple approach might be to MD5 their email address (presumed to have been checked on signup for uniqueness), but then I'd end up with a super long string. This isn't a huge issue, but I'm wondering what techniques there are for shorter GUIDs that won't collide too often (this is obviously the tradeoff, but 12 characters above is pretty short in my opinion)