/** Make a play. Only allows the joined players to  */
app.get('/:gameid/set/:column', (req, res) => {
    const userid = getUserId(req, res)
    const game = games[parseInt(req.params['gameid'])]
    if (game == undefined) {
        res.status(404).json("no such game")
    } else if (game.state != "playing") {
        res.status(403).json("game is not playing")
    } else if (getCurrentPlayer(game) != userid) {
        res.status(403)
        res.json("Not your turn, my friend")
    } else {
        let column = parseInt(req.params['column'])
        dropPiece(game, column)
        res.json(toJson(game, userid))
    }
})