Assume you are talking about an Inverter Type Generator... Thats what I do here but my 2000W Honda Generator sits secured in the tail gate corner of my covered and locked truck bed. When I need to use my Honda Generator I just pull it out onto the tail gate. It is completely out of sight when not in use to help keep it from walking away when unattended.
I can also use a RV 30A to 15A long Adapter (WALMART) and connect my trailer to the generator but in my case I have to flip off a few breakers in my 120VAC Power Panel for a few of the high wattage appliances... The only real big reason to connect my trailer to my generator directly is to be able to run my on-baord converter/charger unit to re-charge my batteries when they get down to the 50% charge state..
All of my low wattage 120VAC items I want to run when not on Shore Power is handled by a low wattage PSW Power Inverter off of the battery bank... I have a 600WATT Power Inverter but usually only ever load it down to around 300watts at times. Makes for a great what I call My Duty Power Inverter which stays on all the time when I am using my trailer.
If you leave your generator outside you really should have it covered with something for bad weather when not in use if the generator is not built to be left outside..
Be aware when running your generator outside not to point it at another trailer or people as it does emit poison CO fumes that are deadly...
Also if your generator is cheap one it may be very loud and this will create problems when camping at camp ground with other campers. Most camp grounds have generator run time restrictions in place so don't get into a situation where you think you can run your generator anytime you want to. I don't know of many public places if any where a generator can run after 8PM at night.
This 8PM restriction just might get in the way for you all wanting to watch HDTV from 8PM to lights out at 10-11PM each night... Need to run things from the batteries and just think about using the generator to re-charge your batteries when you are allowed to run one...
Running extension cords from the generator into your should come in another way other than the door access... You surely can crack a window or come in through the storage bay. Don't want kids or other people tripping on your extension cords etc... This would be a safety violation...
Roy Ken