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("/", "gconnect"); //notify main hall
  47           break;
  48         case "pollclients":
  49         {
  50           const curPage = clients[sid].page;
  51           socket.send(JSON.stringify({code:"pollclients",
  52             sockIds: Object.keys(clients).filter(k =>
  53               k != sid && clients[k].page == curPage
  54             )}));
  55           break;
  56         }
  57         case "pollgamers":
  58           socket.send(JSON.stringify({code:"pollgamers",
  59             sockIds: Object.keys(clients).filter(k =>
  60               k != sid && clients[k].page.indexOf("/game/") >= 0
  61             )}));
  62           break;
  63         case "pagechange":
  64           // page change clients[sid].page --> obj.page
  65 console.log(sid + " : page change: " + clients[sid].page + " --> " + obj.page);
  66           notifyRoom(clients[sid].page, "disconnect");
  67           if (clients[sid].page.indexOf("/game/") >= 0)
  68             notifyRoom("/", "gdisconnect");
  69           clients[sid].page = obj.page;
  70           notifyRoom(obj.page, "connect");
  71           if (obj.page.indexOf("/game/") >= 0)
  72             notifyRoom("/", "gconnect");
  73           break;
  74         case "askidentity":
  75           clients[obj.target].sock.send(JSON.stringify(
  76             {code:"askidentity",from:sid}));
  77           break;
  78         case "askchallenge":
  79           clients[obj.target].sock.send(JSON.stringify(
  80             {code:"askchallenge",from:sid}));
  81           break;
  82         case "askgames":
  83         {
  84           // Check all clients playing, and send them a "askgame" message
  85           let gameSids = {}; //game ID --> [sid1, sid2]
  86           const regexpGid = /\/[a-zA-Z0-9]+$/;
  87           Object.keys(clients).forEach(k => {
  88             if (k != sid && clients[k].page.indexOf("/game/") >= 0)
  89             {
  90               const gid = clients[k].page.match(regexpGid)[0];
  91               if (!gameSids[gid])
  92                 gameSids[gid] = [k];
  93               else
  94                 gameSids[gid].push(k);
  95             }
  96           });
  97           // Request only one client out of 2 (TODO: this is a bit heavy)
  98           // Alt: ask game to all, and filter later?
  99           Object.keys(gameSids).forEach(gid => {
 100             const L = gameSids[gid].length;
 101             const idx = L > 1
 102               ? Math.floor(Math.random() * Math.floor(L))
 103               : 0;
 104             const rid = gameSids[gid][idx];
 105             clients[rid].sock.send(JSON.stringify(
 106               {code:"askgame", from: sid}));
 107           });
 108           break;
 109         }
 110         case "askfullgame":
 111           clients[obj.target].sock.send(JSON.stringify(
 112             {code:"askfullgame", from:sid}));
 113           break;
 114         case "fullgame":
 115           clients[obj.target].sock.send(JSON.stringify(
 116             {code:"fullgame", game:obj.game}));
 117           break;
 118         case "identity":
 119           clients[obj.target].sock.send(JSON.stringify(
 120             {code:"identity",user:obj.user}));
 121           break;
 122         case "refusechallenge":
 123           clients[obj.target].sock.send(JSON.stringify(
 124             {code:"refusechallenge", cid:obj.cid, from:sid}));
 125           break;
 126         case "deletechallenge":
 127           clients[obj.target].sock.send(JSON.stringify(
 128             {code:"deletechallenge", cid:obj.cid, from:sid}));
 129           break;
 130         case "newgame":
 131           clients[obj.target].sock.send(JSON.stringify(
 132             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
 133           break;
 134         case "challenge":
 135           clients[obj.target].sock.send(JSON.stringify(
 136             {code:"challenge", chall:obj.chall, from:sid}));
 137           break;
 138         case "game":
 139           if (!!obj.target)
 140           {
 141             clients[obj.target].sock.send(JSON.stringify(
 142               {code:"game", game:obj.game, from:sid}));
 143           }
 144           else
 145           {
 146             // Notify all room except opponent and me:
 147             notifyRoom("/", "game", {game:obj.game}, [obj.oppsid]);
 148           }
 149           break;
 150         case "newchat":
 151           notifyRoom(clients[sid].page, "newchat", {chat:obj.chat});
 152           break;
 153         // TODO: WebRTC instead in this case (most demanding?)
 154         // --> At least do a "notifyRoom"
 155         case "newmove":
 156           clients[obj.target].sock.send(JSON.stringify(
 157             {code:"newmove", move:obj.move}));
 158           break;
 159         case "lastate":
 160           clients[obj.target].sock.send(JSON.stringify(
 161             {code:"lastate", state:obj.state}));
 162           break;
 163         case "resign":
 164           clients[obj.target].sock.send(JSON.stringify(
 165             {code:"resign", side:obj.side}));
 166           break;
 167         case "abort":
 168           clients[obj.target].sock.send(JSON.stringify(
 169             {code:"abort"}));
 170           break;
 171         case "drawoffer":
 172           clients[obj.target].sock.send(JSON.stringify(
 173             {code:"drawoffer"}));
 174           break;
 175         case "draw":
 176           clients[obj.target].sock.send(JSON.stringify(
 177             {code:"draw", message:obj.message}));
 178           break;
 179       }
 180     });
 181     socket.on("close", () => {
 182       const page = clients[sid].page;
 183       delete clients[sid];
 184       notifyRoom(page, "disconnect");
 185       if (page.indexOf("/game/") >= 0)
 186         notifyRoom("/", "gdisconnect"); //notify main hall
 187     });
 188   });
 189 }