server/sockets.js

   1 const url = require('url');
   2
   3 // Node version in Ubuntu 16.04 does not know about URL class
   4 // NOTE: url is already transformed, without ?xxx=yyy... parts
   5 function getJsonFromUrl(url)
   6 {
   7   const query = url.substr(2); //starts with "/?"
   8   let result = {};
   9   query.split("&").forEach((part) => {
  10     const item = part.split("=");
  11     result[item[0]] = decodeURIComponent(item[1]);
  12   });
  13   return result;
  14 }
  15
  16 module.exports = function(wss) {
  17   let clients = {}; //associative array sid --> socket
  18   wss.on("connection", (socket, req) => {
  19     const query = getJsonFromUrl(req.url);
  20     if (query["page"] != "/" && query["page"].indexOf("/game/") < 0)
  21       return; //other tabs don't need to be connected
  22     const sid = query["sid"];
  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     const messageListener = (objtxt) => {
  35       let obj = JSON.parse(objtxt);
  36       if (!!obj.target && !clients[obj.target])
  37         return; //receiver not connected, nothing we can do
  38       switch (obj.code)
  39       {
  40         case "duplicate":
  41           // Turn off message listening, and send disconnect if needed:
  42           socket.removeListener("message", messageListener);
  43           socket.removeListener("close", closeListener);
  44           // From obj.page to clients[sid].page (TODO: unclear)
  45           if (clients[sid].page != obj.page)
  46           {
  47             notifyRoom(obj.page, "disconnect");
  48             if (obj.page.indexOf("/game/") >= 0)
  49               notifyRoom("/", "gdisconnect");
  50           }
  51           break;
  52         // Wait for "connect" message to notify connection to the room,
  53         // because if game loading is slow the message listener might
  54         // not be ready too early.
  55         case "connect":
  56         {
  57           const curPage = clients[sid].page;
  58           notifyRoom(curPage, "connect"); //Hall or Game
  59           if (curPage.indexOf("/game/") >= 0)
  60             notifyRoom("/", "gconnect"); //notify main hall
  61           break;
  62         }
  63         case "pollclients":
  64         {
  65           const curPage = clients[sid].page;
  66           socket.send(JSON.stringify({code:"pollclients",
  67             sockIds: Object.keys(clients).filter(k =>
  68               k != sid && clients[k].page == curPage
  69             )}));
  70           break;
  71         }
  72         case "pollgamers":
  73           socket.send(JSON.stringify({code:"pollgamers",
  74             sockIds: Object.keys(clients).filter(k =>
  75               k != sid && clients[k].page.indexOf("/game/") >= 0
  76             )}));
  77           break;
  78         case "pagechange":
  79           // page change clients[sid].page --> obj.page
  80           // TODO: some offline rooms don't need to receive disconnect event
  81           notifyRoom(clients[sid].page, "disconnect");
  82           if (clients[sid].page.indexOf("/game/") >= 0)
  83             notifyRoom("/", "gdisconnect");
  84           clients[sid].page = obj.page;
  85           // No need to notify connection: it's self-sent in .vue file
  86           //notifyRoom(obj.page, "connect");
  87           if (obj.page.indexOf("/game/") >= 0)
  88             notifyRoom("/", "gconnect");
  89           break;
  90         case "askidentity":
  91           clients[obj.target].sock.send(JSON.stringify(
  92             {code:"askidentity",from:sid}));
  93           break;
  94         case "asklastate":
  95           clients[obj.target].sock.send(JSON.stringify(
  96             {code:"asklastate",from:sid}));
  97           break;
  98         case "askchallenge":
  99           clients[obj.target].sock.send(JSON.stringify(
 100             {code:"askchallenge",from:sid}));
 101           break;
 102         case "askgames":
 103         {
 104           // Check all clients playing, and send them a "askgame" message
 105           let gameSids = {}; //game ID --> [sid1, sid2]
 106           const regexpGid = /\/[a-zA-Z0-9]+$/;
 107           Object.keys(clients).forEach(k => {
 108             if (k != sid && clients[k].page.indexOf("/game/") >= 0)
 109             {
 110               const gid = clients[k].page.match(regexpGid)[0];
 111               if (!gameSids[gid])
 112                 gameSids[gid] = [k];
 113               else
 114                 gameSids[gid].push(k);
 115             }
 116           });
 117           // Request only one client out of 2 (TODO: this is a bit heavy)
 118           // Alt: ask game to all, and filter later?
 119           Object.keys(gameSids).forEach(gid => {
 120             const L = gameSids[gid].length;
 121             const idx = L > 1
 122               ? Math.floor(Math.random() * Math.floor(L))
 123               : 0;
 124             const rid = gameSids[gid][idx];
 125             clients[rid].sock.send(JSON.stringify(
 126               {code:"askgame", from: sid}));
 127           });
 128           break;
 129         }
 130         case "askgame":
 131           clients[obj.target].sock.send(JSON.stringify(
 132             {code:"askgame", from:sid}));
 133           break;
 134         case "askfullgame":
 135           clients[obj.target].sock.send(JSON.stringify(
 136             {code:"askfullgame", from:sid}));
 137           break;
 138         case "fullgame":
 139           clients[obj.target].sock.send(JSON.stringify(
 140             {code:"fullgame", game:obj.game}));
 141           break;
 142         case "identity":
 143           clients[obj.target].sock.send(JSON.stringify(
 144             {code:"identity",user:obj.user}));
 145           break;
 146         case "refusechallenge":
 147           clients[obj.target].sock.send(JSON.stringify(
 148             {code:"refusechallenge", cid:obj.cid, from:sid}));
 149           break;
 150         case "deletechallenge":
 151           clients[obj.target].sock.send(JSON.stringify(
 152             {code:"deletechallenge", cid:obj.cid, from:sid}));
 153           break;
 154         case "newgame":
 155           clients[obj.target].sock.send(JSON.stringify(
 156             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
 157           break;
 158         case "challenge":
 159           clients[obj.target].sock.send(JSON.stringify(
 160             {code:"challenge", chall:obj.chall, from:sid}));
 161           break;
 162         case "game":
 163           if (!!obj.target)
 164           {
 165             clients[obj.target].sock.send(JSON.stringify(
 166               {code:"game", game:obj.game, from:sid}));
 167           }
 168           else
 169           {
 170             // Notify all room except opponent and me:
 171             notifyRoom("/", "game", {game:obj.game}, [obj.oppsid]);
 172           }
 173           break;
 174         case "newchat":
 175           notifyRoom(clients[sid].page, "newchat", {chat:obj.chat});
 176           break;
 177         // TODO: WebRTC instead in this case (most demanding?)
 178         // --> Or else: at least do a "notifyRoom" (also for draw, resign...)
 179         case "newmove":
 180           clients[obj.target].sock.send(JSON.stringify(
 181             {code:"newmove", move:obj.move}));
 182           break;
 183         case "lastate":
 184           clients[obj.target].sock.send(JSON.stringify(
 185             {code:"lastate", state:obj.state}));
 186           break;
 187         case "resign":
 188           clients[obj.target].sock.send(JSON.stringify(
 189             {code:"resign", side:obj.side}));
 190           break;
 191         case "abort":
 192           clients[obj.target].sock.send(JSON.stringify(
 193             {code:"abort"}));
 194           break;
 195         case "drawoffer":
 196           clients[obj.target].sock.send(JSON.stringify(
 197             {code:"drawoffer"}));
 198           break;
 199         case "draw":
 200           clients[obj.target].sock.send(JSON.stringify(
 201             {code:"draw", message:obj.message}));
 202           break;
 203       }
 204     };
 205     const closeListener = () => {
 206       const page = clients[sid].page;
 207       delete clients[sid];
 208       notifyRoom(page, "disconnect");
 209       if (page.indexOf("/game/") >= 0)
 210         notifyRoom("/", "gdisconnect"); //notify main hall
 211     };
 212     if (!!clients[sid])
 213     {
 214       // Turn off old sock through current client:
 215       clients[sid].sock.send(JSON.stringify({code:"duplicate"}));
 216     }
 217     // Potentially replace current connection:
 218     clients[sid] = {sock: socket, page: query["page"]};
 219     socket.on("message", messageListener);
 220     socket.on("close", closeListener);
 221   });
 222 }