server/sockets.js

   1 const url = require('url');
   2
   3 // Node version in Ubuntu 16.04 does not know about URL class
   4 function getJsonFromUrl(url)
   5 {
   6     const query = url.substr(2); //starts with "/?"
   7     let result = {};
   8     query.split("&").forEach((part) => {
   9         const item = part.split("=");
  10         result[item[0]] = decodeURIComponent(item[1]);
  11     });
  12     return result;
  13 }
  14
  15 // Removal in array of strings (socket IDs)
  16 function remInArray(arr, item)
  17 {
  18     const idx = arr.indexOf(item);
  19     if (idx >= 0)
  20         arr.splice(idx, 1);
  21 }
  22
  23 // TODO: empêcher multi-log du même user (envoyer le user ID + secret en même temps que name et...)
  24 // --> si secret ne matche pas celui trouvé en DB, stop
  25 // TODO: this file "in the end" would be much simpler, essentially just tracking connect/disconnect
  26 // (everything else using WebRTC)
  27 // TODO: lorsque challenge accepté, seul le dernier joueur à accepter envoi message "please start game"
  28 // avec les coordonnées des participants. Le serveur renvoit alors les détails de la partie (couleurs, position)
  29 //TODO: programmatic re-navigation on current game if we receive a move and are not there
  30
  31 module.exports = function(wss) {
  32     let clients = {}; //associative array sid --> socket
  33     wss.on("connection", (socket, req) => {
  34         const query = getJsonFromUrl(req.url);
  35         const sid = query["sid"];
  36         // Ignore duplicate connections (on the same live game that we play):
  37         if (!!clients[sid])
  38             return socket.send(JSON.stringify({code:"duplicate"}));
  39         clients[sid] = socket;
  40         socket.on("message", objtxt => {
  41             let obj = JSON.parse(objtxt);
  42       if (!!obj.oppid && !clients[oppid])
  43         return; //receiver not connected, nothing we can do
  44             switch (obj.code)
  45             {
  46         case "askplayers":
  47           socket.send(JSON.stringify({code:"room", players:clients}));
  48           break;
  49         case "askchallenges":
  50           // TODO: ask directly to people (webRTC)
  51           break;
  52         case "askgames":
  53           // TODO: ask directly to people (webRTC)
  54           break;
  55                 case "newchat":
  56           clients[obj.oppid].send(JSON.stringify({code:"newchat",msg:obj.msg}));
  57                     break;
  58                 // Transmit chats and moves to current room
  59                 // TODO: WebRTC instead in this case (most demanding?)
  60                 case "newmove":
  61           clients[obj.oppid].send(JSON.stringify({code:"newmove",move:obj.move}));
  62                     break;
  63                 // TODO: generalize that for several opponents
  64                 case "ping":
  65                     socket.send(JSON.stringify({code:"pong",gameId:obj.gameId}));
  66                     break;
  67                 case "lastate":
  68           const oppId = obj.oppid;
  69           obj.oppid = sid; //I'm oppid for my opponent
  70           clients[oppId].send(JSON.stringify(obj));
  71                     break;
  72                 // TODO: moreover, here, game info should be sent (through challenge; not stored here)
  73                 case "newgame":
  74           clients[oppId].send(
  75             JSON.stringify(
  76               {code:"newgame",fen:fen,oppid:sid,color:"w",gameid:"TODO"}),
  77             noop);
  78                     break;
  79                 case "cancelnewgame": //if a user cancel his seek
  80                     // TODO: just transmit event
  81                     //delete games[page];
  82                     break;
  83                 // TODO: also other challenge events
  84                 case "resign":
  85           clients[obj.oppid].send(JSON.stringify({code:"resign"}));
  86                     break;
  87                 // TODO: case "challenge" (get ID) --> send to all, "acceptchallenge" (with ID) --> send to all, "cancelchallenge" --> send to all
  88                 // also, "sendgame" (give current game info, if any) --> to new connections, "sendchallenges" (same for challenges) --> to new connections
  89         case "newchallenge":
  90           console.log("challenge received");
  91           console.log(obj.sender);
  92           console.log(obj);
  93           break;
  94             }
  95         });
  96         socket.on("close", () => {
  97             delete clients[sid];
  98       // Notify every other connected client
  99       Object.keys(clients).forEach( k => {
 100         clients[k].send(JSON.stringify({code:"disconnect",sid:sid}));
 101       });
 102         });
 103     });
 104 }