It is your responsibility to research the types of documentation that you will need for your vacation. Do your research a long time before you cruise because you need to give yourself plenty of time to apply for the required types of documentation. Waiting until the "last minute" could result in you not getting your required documentation in time for your cruise. If you do not have proper documentation you could be denied boarding your cruise ship.
If you find yourself close to your departure date and without documentation you are in a very risky situation. You can try to apply for your documentation and try to pay for a "rush processing and delivery", but even by doing this method you run the risk of not getting your documentation in your hands before your cruise.
The most important detail you need to gather here is that you must and should research documentation requirements in well in advance of your cruise. Paying attention to all of the little details can make a big difference in how your cruise vacation goes!