Drake Sued -- Pulls Diva Move and Cancels Concert ... Allegedly

Drake is a little too full of himself ... bailing on 2 concerts to which he committed before blowing up, and agreeing to perform only if he was paid a fame premium -- this according to a new lawsuit.

Several Chicago concert promoters claim Drake agreed to do the shows in 2012, just before he became very rich and very famous. According to the suit, the now-famous Drake said he would take the stage ONLY if the promoters would up the ante.

The show was set for March, 2012 at a venue that held 8,500 people. Drake performed 3 months later at a nearby venue that seated 28,000.