Three bandits with guns and a stun-gun “cane” pistol-whipped and robbed workers at an Upper East Side supermarket who refused to let them into the safe, The Post has learned.

Daniel Nieves, 25, and two male accomplices allegedly attacked the workers in the Fairway market on East 86th Street at 3:40 a.m. Monday, striking two with a gun and zapping another, sources said.

Nieves was arrested nearby.