Communicating via Ajax

Having created a game, we need a way of playing it. Since the whole point of a guessing game is that the word is secret, we don't want to send the whole word to the client. Instead, we just want to let clients know the length of the word and provide a way for them to verify their guesses.

To do this, we'll first need to expand our games service module:

class Game {
    constructor(id, setBy, word) {
        this.id = id;
        this.setBy = setBy;
        this.word = word.toUpperCase();
    }
    
    positionsOf(character) {
        let positions = [];
        for (let i in this.word) {
            if (this.word[i] === character.toUpperCase()) {
                positions.push(i);
            }
        }
        return positions;
    }
}

Now we can add two new routes to our games route:

const checkGameExists = function(id, res, callback) {
    const game = service.get(id);
    if (game) {
        callback(game);
    } else {
        res.status(404).send('Non-existent...