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     const sid = query["sid"];
  21     const notifyRoom = (page,code,obj={},excluded=[]) => {
  22       Object.keys(clients).forEach(k => {
  23         if (k in excluded)
  24           return;
  25         if (k != sid && clients[k].page == page)
  26         {
  27           clients[k].sock.send(JSON.stringify(Object.assign(
  28             {code:code, from:sid}, obj)));
  29         }
  30       });
  31     };
  32     const messageListener = (objtxt) => {
  33       let obj = JSON.parse(objtxt);
  34       if (!!obj.target && !clients[obj.target])
  35         return; //receiver not connected, nothing we can do
  36       switch (obj.code)
  37       {
  38         case "duplicate":
  39           // Turn off message listening, and send disconnect if needed:
  40           socket.removeListener("message", messageListener);
  41           socket.removeListener("close", closeListener);
  42           if (clients[sid].page != obj.page)
  43           {
  44             notifyRoom(clients[sid].page, "disconnect");
  45             if (clients[sid].page.indexOf("/game/") >= 0)
  46               notifyRoom("/", "gdisconnect");
  47           }
  48           break;
  49         // Wait for "connect" message to notify connection to the room,
  50         // because if game loading is slow the message listener might
  51         // not be ready too early.
  52         case "connect":
  53         {
  54           const curPage = clients[sid].page;
  55           notifyRoom(curPage, "connect"); //Hall or Game
  56           if (curPage.indexOf("/game/") >= 0)
  57             notifyRoom("/", "gconnect"); //notify main hall
  58           break;
  59         }
  60         case "pollclients":
  61         {
  62           const curPage = clients[sid].page;
  63           socket.send(JSON.stringify({code:"pollclients",
  64             sockIds: Object.keys(clients).filter(k =>
  65               k != sid && clients[k].page == curPage
  66             )}));
  67           break;
  68         }
  69         case "pollgamers":
  70           socket.send(JSON.stringify({code:"pollgamers",
  71             sockIds: Object.keys(clients).filter(k =>
  72               k != sid && clients[k].page.indexOf("/game/") >= 0
  73             )}));
  74           break;
  75         case "pagechange":
  76           // page change clients[sid].page --> obj.page
  77           // TODO: some offline rooms don't need to receive disconnect event
  78           notifyRoom(clients[sid].page, "disconnect");
  79           if (clients[sid].page.indexOf("/game/") >= 0)
  80             notifyRoom("/", "gdisconnect");
  81           clients[sid].page = obj.page;
  82           // No need to notify connection: it's self-sent in .vue file
  83           //notifyRoom(obj.page, "connect");
  84           if (obj.page.indexOf("/game/") >= 0)
  85             notifyRoom("/", "gconnect");
  86           break;
  87         case "askidentity":
  88           clients[obj.target].sock.send(JSON.stringify(
  89             {code:"askidentity",from:sid}));
  90           break;
  91         case "asklastate":
  92           clients[obj.target].sock.send(JSON.stringify(
  93             {code:"asklastate",from:sid}));
  94           break;
  95         case "askchallenge":
  96           clients[obj.target].sock.send(JSON.stringify(
  97             {code:"askchallenge",from:sid}));
  98           break;
  99         case "askgames":
 100         {
 101           // Check all clients playing, and send them a "askgame" message
 102           let gameSids = {}; //game ID --> [sid1, sid2]
 103           const regexpGid = /\/[a-zA-Z0-9]+$/;
 104           Object.keys(clients).forEach(k => {
 105             if (k != sid && clients[k].page.indexOf("/game/") >= 0)
 106             {
 107               const gid = clients[k].page.match(regexpGid)[0];
 108               if (!gameSids[gid])
 109                 gameSids[gid] = [k];
 110               else
 111                 gameSids[gid].push(k);
 112             }
 113           });
 114           // Request only one client out of 2 (TODO: this is a bit heavy)
 115           // Alt: ask game to all, and filter later?
 116           Object.keys(gameSids).forEach(gid => {
 117             const L = gameSids[gid].length;
 118             const idx = L > 1
 119               ? Math.floor(Math.random() * Math.floor(L))
 120               : 0;
 121             const rid = gameSids[gid][idx];
 122             clients[rid].sock.send(JSON.stringify(
 123               {code:"askgame", from: sid}));
 124           });
 125           break;
 126         }
 127         case "askgame":
 128           clients[obj.target].sock.send(JSON.stringify(
 129             {code:"askgame", from:sid}));
 130           break;
 131         case "askfullgame":
 132           clients[obj.target].sock.send(JSON.stringify(
 133             {code:"askfullgame", from:sid}));
 134           break;
 135         case "fullgame":
 136           clients[obj.target].sock.send(JSON.stringify(
 137             {code:"fullgame", game:obj.game}));
 138           break;
 139         case "identity":
 140           clients[obj.target].sock.send(JSON.stringify(
 141             {code:"identity",user:obj.user}));
 142           break;
 143         case "refusechallenge":
 144           clients[obj.target].sock.send(JSON.stringify(
 145             {code:"refusechallenge", cid:obj.cid, from:sid}));
 146           break;
 147         case "deletechallenge":
 148           clients[obj.target].sock.send(JSON.stringify(
 149             {code:"deletechallenge", cid:obj.cid, from:sid}));
 150           break;
 151         case "newgame":
 152           clients[obj.target].sock.send(JSON.stringify(
 153             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
 154           break;
 155         case "challenge":
 156           clients[obj.target].sock.send(JSON.stringify(
 157             {code:"challenge", chall:obj.chall, from:sid}));
 158           break;
 159         case "game":
 160           if (!!obj.target)
 161           {
 162             clients[obj.target].sock.send(JSON.stringify(
 163               {code:"game", game:obj.game, from:sid}));
 164           }
 165           else
 166           {
 167             // Notify all room except opponent and me:
 168             notifyRoom("/", "game", {game:obj.game}, [obj.oppsid]);
 169           }
 170           break;
 171         case "newchat":
 172           notifyRoom(clients[sid].page, "newchat", {chat:obj.chat});
 173           break;
 174         // TODO: WebRTC instead in this case (most demanding?)
 175         // --> Or else: at least do a "notifyRoom" (also for draw, resign...)
 176         case "newmove":
 177           clients[obj.target].sock.send(JSON.stringify(
 178             {code:"newmove", move:obj.move}));
 179           break;
 180         case "lastate":
 181           clients[obj.target].sock.send(JSON.stringify(
 182             {code:"lastate", state:obj.state}));
 183           break;
 184         case "resign":
 185           clients[obj.target].sock.send(JSON.stringify(
 186             {code:"resign", side:obj.side}));
 187           break;
 188         case "abort":
 189           clients[obj.target].sock.send(JSON.stringify(
 190             {code:"abort"}));
 191           break;
 192         case "drawoffer":
 193           clients[obj.target].sock.send(JSON.stringify(
 194             {code:"drawoffer"}));
 195           break;
 196         case "draw":
 197           clients[obj.target].sock.send(JSON.stringify(
 198             {code:"draw", message:obj.message}));
 199           break;
 200       }
 201     };
 202     const closeListener = () => {
 203       const page = clients[sid].page;
 204       delete clients[sid];
 205       notifyRoom(page, "disconnect");
 206       if (page.indexOf("/game/") >= 0)
 207         notifyRoom("/", "gdisconnect"); //notify main hall
 208     };
 209     if (!!clients[sid])
 210     {
 211       // Turn off old sock through current client:
 212       clients[sid].sock.send(JSON.stringify({code:"duplicate"}));
 213     }
 214     // Potentially replace current connection:
 215     clients[sid] = {sock: socket, page: query["page"]};
 216     socket.on("message", messageListener);
 217     socket.on("close", closeListener);
 218   });
 219 }