Shulchan Arukh, Orach Chayim 680/שולחן ערוך·אורח חיים תר״פ

1Not to Leave the Lights Near the Entrance on the Sabbath Eve, 2 Seifim:

2On the Sabbath Eve it is prohibited to mount the lights on the door itself, behind the door, but there is [an opinion] that permits [this]. [And see above Section 277 Paragraph 1.]