Miles has been going to Ace Bar all his life.

His face has grayed there. Friends have come and gone. He never paid for a drink, but rarely walked out of the East Village bar with an empty stomach. He may have purged his dinner on the floor a time or two, his fellow bar patrons said, but who among them hadn’t done the same?

Over the past year, though, Miles has become the latest subject of what may be the city’s least funny running joke: A dog walks into a bar — and the health department threatens to issue a violation for allowing live animals in a food establishment.

“He’s a dog, but I swear he looks sad,” Mike Israely, 33, said of Miles, his 9-year-old boxer-pug mix, as the dog peered through Ace Bar’s glass doors Thursday night. “Coming here was part of our evening walk.”. . .