The usage "in case X, we want to..." is sort of strange here.  The phrase "In case X happens, do Y" usually means "always do Y so that we're safe if X happens", not "do Y only if X happens.  I would change this to "In the case where the author field is missing..." or "When the author field is missing..." or "If the author field is missing...".

See http://www.bbc.co.uk/worldservice/learningenglish/grammar/learnit/learnitv261.shtml (near the bottom in the yellow box).