User blog:Tymewalk/Brute-forcing So Good's JDNow Number

So as of October 22, 2015, Just Dance Now uses new links with numbers. Unfortunately, this means that songs like So Good can't be accessed with the new links, as we don't know the numbers. You can go to this JDNow API page to get numbers, but that only works for released songs.

While using that page I found something interesting. All the version numbers are Unix timestamps with milliseconds (this page converts them to human-readable time). This explains why Taste The Feeling had two numbers, one which was older - Ubisoft released a new version under a new number (the time they added the new version to the servers). This means that the version number will never be less than 1400000000 or greater than 1500000000 - the first one is before the new system was used, the last one is about a year in the future.

What's more, all the songs that were in the old version - Safe And Sound, Barbra Streisand, My Main Girl, etc. had a timestamp for the day of October 12, 2015 - 10 days before the update that used the new links was released. Given that they're so close to one another for 150+ songs, this means that they most likely transferred everything at once - everything including So Good and any other JDNow beta songs.

So in theory, one could access So Good with a number, just like any other Just Dance Now song. Using this I wrote a program to try every possible time within 1 second of every other song's timestamp. This leads to 50,800 different numbers. Currently I've got ~48,000 numbers remaining. I'll update this when something exciting happens.

Grab some popcorn, we're going to be here a while.