From Longman Dictionary of Contemporary Englishbe on the doorbe on the doorAPTBOto work at the entrance to a theatre, club etc, collecting tickets → door
Examples from the Corpus
be on the door• One of his hands was on the door, the other extended to her.• The jury was told that Mr Johnson was on the door when the four arrived at his party at about three am.• Her name was on the door in a little metal card holder.• Now the millworkers craned their necks to read what was on the doors. 