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     if (!!clients[sid])
  21       return socket.send(JSON.stringify({code:"duplicate"}));
  22     clients[sid] = {sock: socket, page: query["page"]};
  23     const notifyRoom = (page,code,obj={},excluded=[]) => {
  24       Object.keys(clients).forEach(k => {
  25         if (k in excluded)
  26           return;
  27         if (k != sid && clients[k].page == page)
  28         {
  29           clients[k].sock.send(JSON.stringify(Object.assign(
  30             {code:code, from:sid}, obj)));
  31         }
  32       });
  33     };
  34     // Wait for "connect" message to notify connection to the room,
  35     // because if game loading is slow the message listener might
  36     // not be ready too early.
  37     socket.on("message", objtxt => {
  38       let obj = JSON.parse(objtxt);
  39       if (!!obj.target && !clients[obj.target])
  40         return; //receiver not connected, nothing we can do
  41       switch (obj.code)
  42       {
  43         case "connect":
  44           notifyRoom(query["page"], "connect"); //Hall or Game
  45           if (query["page"].indexOf("/game/") >= 0)
  46             notifyRoom("/", "connect"); //notify main hall
  47           break;
  48         case "pollclients":
  49           const curPage = clients[sid].page;
  50           socket.send(JSON.stringify({code:"pollclients",
  51             sockIds: Object.keys(clients).filter(k => k != sid &&
  52               (clients[k].page == curPage ||
  53               // Consider that people playing are in Hall too:
  54               (curPage == "/" && clients[k].page.indexOf("/game/") >= 0))
  55             )}));
  56           break;
  57         case "pagechange":
  58           notifyRoom(clients[sid].page, "disconnect");
  59           if (clients[sid].page.indexOf("/game/") >= 0)
  60             notifyRoom("/", "disconnect");
  61           clients[sid].page = obj.page;
  62           notifyRoom(obj.page, "connect");
  63           if (obj.page.indexOf("/game/") >= 0)
  64             notifyRoom("/", "connect");
  65           break;
  66         case "askidentity":
  67           clients[obj.target].sock.send(JSON.stringify(
  68             {code:"askidentity",from:sid}));
  69           break;
  70         case "askchallenge":
  71           clients[obj.target].sock.send(JSON.stringify(
  72             {code:"askchallenge",from:sid}));
  73           break;
  74         case "askgames":
  75         {
  76           // Check all clients playing, and send them a "askgame" message
  77           let gameSids = {}; //game ID --> [sid1, sid2]
  78           const regexpGid = /\/[a-zA-Z0-9]+$/;
  79           Object.keys(clients).forEach(k => {
  80             if (k != sid && clients[k].page.indexOf("/game/") >= 0)
  81             {
  82               const gid = clients[k].page.match(regexpGid)[0];
  83               if (!gameSids[gid])
  84                 gameSids[gid] = [k];
  85               else
  86                 gameSids[gid].push(k);
  87             }
  88           });
  89           // Request only one client out of 2 (TODO: this is a bit heavy)
  90           // Alt: ask game to all, and filter later?
  91           Object.keys(gameSids).forEach(gid => {
  92             const L = gameSids[gid].length;
  93             const idx = L > 1
  94               ? Math.floor(Math.random() * Math.floor(L))
  95               : 0;
  96             const rid = gameSids[gid][idx];
  97             clients[rid].sock.send(JSON.stringify(
  98               {code:"askgame", from: sid}));
  99           });
 100           break;
 101         }
 102         case "askfullgame":
 103           clients[obj.target].sock.send(JSON.stringify(
 104             {code:"askfullgame", from:sid}));
 105           break;
 106         case "fullgame":
 107           clients[obj.target].sock.send(JSON.stringify(
 108             {code:"fullgame", game:obj.game}));
 109           break;
 110         case "identity":
 111           clients[obj.target].sock.send(JSON.stringify(
 112             {code:"identity",user:obj.user}));
 113           break;
 114         case "refusechallenge":
 115           clients[obj.target].sock.send(JSON.stringify(
 116             {code:"refusechallenge", cid:obj.cid, from:sid}));
 117           break;
 118         case "deletechallenge":
 119           clients[obj.target].sock.send(JSON.stringify(
 120             {code:"deletechallenge", cid:obj.cid, from:sid}));
 121           break;
 122         case "newgame":
 123           clients[obj.target].sock.send(JSON.stringify(
 124             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
 125           break;
 126         case "challenge":
 127           clients[obj.target].sock.send(JSON.stringify(
 128             {code:"challenge", chall:obj.chall, from:sid}));
 129           break;
 130         case "game":
 131           if (!!obj.target)
 132           {
 133             clients[obj.target].sock.send(JSON.stringify(
 134               {code:"game", game:obj.game, from:sid}));
 135           }
 136           else
 137           {
 138             // Notify all room except opponent and me:
 139             notifyRoom("/", "game", {game:obj.game}, [obj.oppsid]);
 140           }
 141           break;
 142         case "newchat":
 143           // WARNING: do not use query["page"], because the page may change
 144           notifyRoom(clients[sid].page, "newchat",
 145             {msg: obj.msg, name: obj.name});
 146           break;
 147         // TODO: WebRTC instead in this case (most demanding?)
 148         case "newmove":
 149           clients[obj.target].sock.send(JSON.stringify(
 150             {code:"newmove", move:obj.move}));
 151           break;
 152         case "lastate":
 153           clients[obj.target].sock.send(JSON.stringify(
 154             {code:"lastate", state:obj.state}));
 155           break;
 156         case "resign":
 157           clients[obj.target].sock.send(JSON.stringify(
 158             {code:"resign", side:obj.side}));
 159           break;
 160         case "abort":
 161           clients[obj.target].sock.send(JSON.stringify(
 162             {code:"abort"}));
 163           break;
 164         case "drawoffer":
 165           clients[obj.target].sock.send(JSON.stringify(
 166             {code:"drawoffer"}));
 167           break;
 168         case "draw":
 169           clients[obj.target].sock.send(JSON.stringify(
 170             {code:"draw", message:obj.message}));
 171           break;
 172       }
 173     });
 174     socket.on("close", () => {
 175       const page = clients[sid].page;
 176       delete clients[sid];
 177       notifyRoom(page, "disconnect");
 178       if (page.indexOf("/game/") >= 0)
 179         notifyRoom("/", "disconnect"); //notify main hall
 180     });
 181   });
 182 }