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       //console.log(obj.code);
  34       switch (obj.code)
  35       {
  36         case "pollclients":
  37           socket.send(JSON.stringify({code:"pollclients",
  38             sockIds:Object.keys(clients).filter(k => k != sid)}));
  39           break;
  40         case "askidentity":
  41           clients[obj.target].send(
  42             JSON.stringify({code:"askidentity",from:sid}));
  43           break;
  44         case "askchallenge":
  45           clients[obj.target].send(
  46             JSON.stringify({code:"askchallenge",from:sid}));
  47           break;
  48         case "askgame":
  49           clients[obj.target].send(
  50             JSON.stringify({code:"askgame",from:sid}));
  51           break;
  52         case "identity":
  53           clients[obj.target].send(
  54             JSON.stringify({code:"identity",user:obj.user}));
  55           break;
  56         case "challenge":
  57           clients[obj.target].send(
  58             JSON.stringify({code:"challenge", chall:obj.chall, from:sid}));
  59           break;
  60         case "acceptchallenge":
  61           clients[obj.target].send(
  62             JSON.stringify({code:"acceptchallenge", cid:obj.cid, from:sid}));
  63           break;
  64         case "withdrawchallenge":
  65           clients[obj.target].send(
  66             JSON.stringify({code:"withdrawchallenge", cid:obj.cid, from:sid}));
  67           break;
  68         case "refusechallenge":
  69           clients[obj.target].send(
  70             JSON.stringify({code:"refusechallenge", cid:obj.cid, from:sid}));
  71           break;
  72         case "deletechallenge":
  73           clients[obj.target].send(
  74             JSON.stringify({code:"deletechallenge", cid:obj.cid, from:sid}));
  75           break;
  76         case "newgame":
  77           clients[obj.target].send(JSON.stringify(
  78             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
  79           break;
  80         case "game":
  81           // TODO: relay (live) game to other player
  82           break;
  83         case "newchat":
  84           clients[obj.target].send(JSON.stringify({code:"newchat",msg:obj.msg}));
  85           break;
  86         // Transmit chats and moves to current room
  87         // TODO: WebRTC instead in this case (most demanding?)
  88         case "newmove":
  89           clients[obj.target].send(JSON.stringify({code:"newmove",move:obj.move}));
  90           break;
  91         // TODO: generalize that for several opponents
  92         case "ping":
  93           socket.send(JSON.stringify({code:"pong",gameId:obj.gameId}));
  94           break;
  95         case "lastate":
  96           const oppId = obj.target;
  97           obj.oppid = sid; //I'm the opponent of my opponent(s)
  98           clients[oppId].send(JSON.stringify(obj));
  99           break;
 100         case "resign":
 101           clients[obj.target].send(JSON.stringify({code:"resign"}));
 102           break;
 103         case "abort":
 104           clients[obj.target].send(JSON.stringify({code:"abort",msg:obj.msg}));
 105           break;
 106       }
 107     });
 108     socket.on("close", () => {
 109       delete clients[sid];
 110       // Notify every other connected client
 111       Object.keys(clients).forEach( k => {
 112         clients[k].send(JSON.stringify({code:"disconnect",sid:sid}));
 113       });
 114     });
 115   });
 116 }