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 module.exports = function(wss) {
  16   let clients = {}; //associative array sid --> socket
  17   wss.on("connection", (socket, req) => {
  18     const query = getJsonFromUrl(req.url);
  19     const sid = query["sid"];
  20     // TODO: later, allow duplicate connections (shouldn't be much more complicated)
  21     if (!!clients[sid])
  22       return socket.send(JSON.stringify({code:"duplicate"}));
  23     clients[sid] = socket;
  24     // Notify room:
  25     Object.keys(clients).forEach(k => {
  26       if (k != sid)
  27         clients[k].send(JSON.stringify({code:"connect",sid:sid}));
  28     });
  29     socket.on("message", objtxt => {
  30       let obj = JSON.parse(objtxt);
  31       if (!!obj.target && !clients[obj.target])
  32         return; //receiver not connected, nothing we can do
  33       switch (obj.code)
  34       {
  35         case "pollclients":
  36           socket.send(JSON.stringify({code:"pollclients",
  37             sockIds:Object.keys(clients).filter(k => k != sid)}));
  38           break;
  39         case "askidentity":
  40           clients[obj.target].send(
  41             JSON.stringify({code:"askidentity",from:sid}));
  42           break;
  43         case "askchallenge":
  44           clients[obj.target].send(
  45             JSON.stringify({code:"askchallenge",from:sid}));
  46           break;
  47         case "askgame":
  48           clients[obj.target].send(
  49             JSON.stringify({code:"askgame",from:sid}));
  50           break;
  51         case "identity":
  52           clients[obj.target].send(
  53             JSON.stringify({code:"identity",user:obj.user}));
  54           break;
  55         case "refusechallenge":
  56           clients[obj.target].send(
  57             JSON.stringify({code:"refusechallenge", cid:obj.cid, from:sid}));
  58           break;
  59         case "deletechallenge":
  60           clients[obj.target].send(
  61             JSON.stringify({code:"deletechallenge", cid:obj.cid, from:sid}));
  62           break;
  63         case "newgame":
  64           clients[obj.target].send(JSON.stringify(
  65             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
  66           break;
  67         case "challenge":
  68           clients[obj.target].send(JSON.stringify(
  69             {code:"challenge", chall:obj.chall, from:sid}));
  70           break;
  71         case "game":
  72           clients[obj.target].send(JSON.stringify(
  73             {code:"game", game:obj.game, from:sid}));
  74           break;
  75         case "newchat":
  76           clients[obj.target].send(JSON.stringify({code:"newchat",msg:obj.msg}));
  77           break;
  78         // TODO: WebRTC instead in this case (most demanding?)
  79         case "newmove":
  80           clients[obj.target].send(JSON.stringify({code:"newmove",move:obj.move}));
  81           break;
  82         case "ping":
  83           // If this code is reached, then obj.target is connected
  84           socket.send(JSON.stringify({code:"pong"}));
  85           break;
  86         case "lastate":
  87           const oppId = obj.target;
  88           obj.oppid = sid; //I'm the opponent of my opponent(s)
  89           clients[oppId].send(JSON.stringify(obj));
  90           break;
  91         case "resign":
  92           clients[obj.target].send(JSON.stringify({code:"resign"}));
  93           break;
  94         case "abort":
  95           clients[obj.target].send(JSON.stringify({code:"abort",msg:obj.msg}));
  96           break;
  97         case "drawoffer":
  98           clients[obj.target].send(JSON.stringify({code:"drawoffer"}));
  99           break;
 100         case "draw":
 101           clients[obj.target].send(JSON.stringify({code:"draw"}));
 102           break;
 103       }
 104     });
 105     socket.on("close", () => {
 106       delete clients[sid];
 107       // Notify every other connected client
 108       Object.keys(clients).forEach( k => {
 109         clients[k].send(JSON.stringify({code:"disconnect",sid:sid}));
 110       });
 111     });
 112   });
 113 }