If you're expecting to play online on your PS4 tonight, you might want to reconsidert.
Sony has announced that PSN will be down tonight from 9:30 PM PT until 11:30 PM PT. There's no word on what will be done during this maintenance period, but it will affect the PlayStation Store, account management, and video.
Luckily, Sony typically completes these maintenance windows on time, so you can likely expect the services to be restored as planned.
In the meantime, you can still play just about any game that doesn't require online connectivity. Just make sure you have all your updates done before PSN goes down!