As of the 31st of July, there have been no warnings except exercise a high degree of caution. It's generally safe to travel if you are willing to follow the rules and laws within a society. When visiting Dubai you want to make sure you check for any kind of warning that may be active for travelers.
Learn all you can about a culture before you visit, and try not to go during troubling times. It may be hard in this day and age to travel safe, but there are many types of problems that can even come from you walking to the store in your own neighborhood!
Crime statistics can be found for many places worldwide so you can research any area before visiting.
1 - http://travel.gc.ca/destinations/united-arab-emirates
2 - https://en.wikipedia.org/wiki/List_of_countries_by_intentional_homicide_rate