If they are Christmas lights and don't require an earth (2 pin plug )I have a question regarding those light socket adapter that allow you to screw into a light socket and added an inline switched outlet in the process.
What are some of the things to watch out for when using an outlet like this? Is there some sort of wattage restriction on what you can plug into it? I am thinking you can't plug in a heavy duty demolition hammer to it right? It is going through the lighting fixture's wiring and components. Can you put this on an exterior wall sconce and hook up 100' of Christmas lights?
And the load is not high, then should be ok !
do you know what the load is ?
Don't use three pin plug type Christmas lights
as they require an earth, which the light will not have.