node-gamekit-auth

A simple node.js helper to auth an user using Apple GameKit

Why ?

You now why, like me, you probably lost 2 hours, looking for a simple solution to auth a user to your node.js app using GameKit

Todo

Currently there is no caching, this would probably be something nice to do Also more descriptive error would be cool

Usage

Install

npm install --save gamekit-auth

Simple stupid iOS side example usign Alamofire

import Alamofire
import GameKit

class myCoolVc {
    func initGK() {
        let localPlayer = GKLocalPlayer.localPlayer()
        localPlayer.authenticateHandler = { vc, err in
            if let vc = vc {
                self.showViewController(vc, sender: self)
            } else if localPlayer.authenticated {
                login(localPlayer) { err in
                    debugPrint(err)
                    // READY TO GO
                }
            } else {
                debugPrint("Noeeeees")
            }
        }
    }

    func login(localPlayer: GKLocalPlayer, completionHandler: (NSError?) -> Void) {
        localPlayer.generateIdentityVerificationSignatureWithCompletionHandler { publicKeyUrl, signature, salt, timestamp, err in
            guard err == nil else { return completionHandler(err) }
            
            let parameters = [
                "playerId": playerId!,
                "publicKeyURL": publicKeyUrl!.absoluteString,
                "signature": signature!.base64EncodedStringWithOptions([]),
                "salt": salt!.base64EncodedStringWithOptions([]),
                "timestamp": String(timestamp)
            ]
            
            Alamofire.request(.POST, YOUR_API_URL, parameters: parameters, encoding: .JSON)
                .validate()
                .responseJSON { response in
                    switch response.result {
                    case .Success:
                        return completionHandler(nil)
                    case .Failure(let err):
                        return completionHandler(err)
                    }
            }
        }
    }

}

Node.js side

var gameKitAuth = require('gamekit-auth');

var bundleIdentifier = 'com.cool-company.cool-app';

function myCoolExressController(req, res, next) {
    gameKitAuth({
        playerId: req.body.playerId
        publicKeyURL: req.body.publicKeyURL,
        signature: req.body.signature,
        salt: req.body.salt,
        timestamp: req.body.timestamp,
        bundleIdentifier: bundleIdentifier
    }).then(function () {
        // Success !
        res.status(200).end();
    }).catch(function (err) {
        console.error(err);
        res.status(400).end();
    });
}