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           // From obj.page to clients[sid].page (TODO: unclear)
  43           if (clients[sid].page != obj.page)
  44           {
  45             notifyRoom(obj.page, "disconnect");
  46             if (obj.page.indexOf("/game/") >= 0)
  47               notifyRoom("/", "gdisconnect");
  48           }
  49           break;
  50         // Wait for "connect" message to notify connection to the room,
  51         // because if game loading is slow the message listener might
  52         // not be ready too early.
  53         case "connect":
  54         {
  55           const curPage = clients[sid].page;
  56           notifyRoom(curPage, "connect"); //Hall or Game
  57           if (curPage.indexOf("/game/") >= 0)
  58             notifyRoom("/", "gconnect"); //notify main hall
  59           break;
  60         }
  61         case "pollclients":
  62         {
  63           const curPage = clients[sid].page;
  64           socket.send(JSON.stringify({code:"pollclients",
  65             sockIds: Object.keys(clients).filter(k =>
  66               k != sid && clients[k].page == curPage
  67             )}));
  68           break;
  69         }
  70         case "pollgamers":
  71           socket.send(JSON.stringify({code:"pollgamers",
  72             sockIds: Object.keys(clients).filter(k =>
  73               k != sid && clients[k].page.indexOf("/game/") >= 0
  74             )}));
  75           break;
  76         case "pagechange":
  77           // page change clients[sid].page --> obj.page
  78           // TODO: some offline rooms don't need to receive disconnect event
  79           notifyRoom(clients[sid].page, "disconnect");
  80           if (clients[sid].page.indexOf("/game/") >= 0)
  81             notifyRoom("/", "gdisconnect");
  82           clients[sid].page = obj.page;
  83           // No need to notify connection: it's self-sent in .vue file
  84           //notifyRoom(obj.page, "connect");
  85           if (obj.page.indexOf("/game/") >= 0)
  86             notifyRoom("/", "gconnect");
  87           break;
  88         case "askidentity":
  89           clients[obj.target].sock.send(JSON.stringify(
  90             {code:"askidentity",from:sid}));
  91           break;
  92         case "asklastate":
  93           clients[obj.target].sock.send(JSON.stringify(
  94             {code:"asklastate",from:sid}));
  95           break;
  96         case "askchallenge":
  97           clients[obj.target].sock.send(JSON.stringify(
  98             {code:"askchallenge",from:sid}));
  99           break;
 100         case "askgames":
 101         {
 102           // Check all clients playing, and send them a "askgame" message
 103           let gameSids = {}; //game ID --> [sid1, sid2]
 104           const regexpGid = /\/[a-zA-Z0-9]+$/;
 105           Object.keys(clients).forEach(k => {
 106             if (k != sid && clients[k].page.indexOf("/game/") >= 0)
 107             {
 108               const gid = clients[k].page.match(regexpGid)[0];
 109               if (!gameSids[gid])
 110                 gameSids[gid] = [k];
 111               else
 112                 gameSids[gid].push(k);
 113             }
 114           });
 115           // Request only one client out of 2 (TODO: this is a bit heavy)
 116           // Alt: ask game to all, and filter later?
 117           Object.keys(gameSids).forEach(gid => {
 118             const L = gameSids[gid].length;
 119             const idx = L > 1
 120               ? Math.floor(Math.random() * Math.floor(L))
 121               : 0;
 122             const rid = gameSids[gid][idx];
 123             clients[rid].sock.send(JSON.stringify(
 124               {code:"askgame", from: sid}));
 125           });
 126           break;
 127         }
 128         case "askgame":
 129           clients[obj.target].sock.send(JSON.stringify(
 130             {code:"askgame", from:sid}));
 131           break;
 132         case "askfullgame":
 133           clients[obj.target].sock.send(JSON.stringify(
 134             {code:"askfullgame", from:sid}));
 135           break;
 136         case "fullgame":
 137           clients[obj.target].sock.send(JSON.stringify(
 138             {code:"fullgame", game:obj.game}));
 139           break;
 140         case "identity":
 141           clients[obj.target].sock.send(JSON.stringify(
 142             {code:"identity",user:obj.user}));
 143           break;
 144         case "refusechallenge":
 145           clients[obj.target].sock.send(JSON.stringify(
 146             {code:"refusechallenge", cid:obj.cid, from:sid}));
 147           break;
 148         case "deletechallenge":
 149           clients[obj.target].sock.send(JSON.stringify(
 150             {code:"deletechallenge", cid:obj.cid, from:sid}));
 151           break;
 152         case "newgame":
 153           clients[obj.target].sock.send(JSON.stringify(
 154             {code:"newgame", gameInfo:obj.gameInfo, cid:obj.cid}));
 155           break;
 156         case "challenge":
 157           clients[obj.target].sock.send(JSON.stringify(
 158             {code:"challenge", chall:obj.chall, from:sid}));
 159           break;
 160         case "game":
 161           if (!!obj.target)
 162           {
 163             clients[obj.target].sock.send(JSON.stringify(
 164               {code:"game", game:obj.game, from:sid}));
 165           }
 166           else
 167           {
 168             // Notify all room except opponent and me:
 169             notifyRoom("/", "game", {game:obj.game}, [obj.oppsid]);
 170           }
 171           break;
 172         case "newchat":
 173           notifyRoom(clients[sid].page, "newchat", {chat:obj.chat});
 174           break;
 175         // TODO: WebRTC instead in this case (most demanding?)
 176         // --> Or else: at least do a "notifyRoom" (also for draw, resign...)
 177         case "newmove":
 178           clients[obj.target].sock.send(JSON.stringify(
 179             {code:"newmove", move:obj.move}));
 180           break;
 181         case "lastate":
 182           clients[obj.target].sock.send(JSON.stringify(
 183             {code:"lastate", state:obj.state}));
 184           break;
 185         case "resign":
 186           clients[obj.target].sock.send(JSON.stringify(
 187             {code:"resign", side:obj.side}));
 188           break;
 189         case "abort":
 190           clients[obj.target].sock.send(JSON.stringify(
 191             {code:"abort"}));
 192           break;
 193         case "drawoffer":
 194           clients[obj.target].sock.send(JSON.stringify(
 195             {code:"drawoffer"}));
 196           break;
 197         case "draw":
 198           clients[obj.target].sock.send(JSON.stringify(
 199             {code:"draw", message:obj.message}));
 200           break;
 201       }
 202     };
 203     const closeListener = () => {
 204       const page = clients[sid].page;
 205       delete clients[sid];
 206       notifyRoom(page, "disconnect");
 207       if (page.indexOf("/game/") >= 0)
 208         notifyRoom("/", "gdisconnect"); //notify main hall
 209     };
 210     if (!!clients[sid])
 211     {
 212       // Turn off old sock through current client:
 213       clients[sid].sock.send(JSON.stringify({code:"duplicate"}));
 214     }
 215     // Potentially replace current connection:
 216     clients[sid] = {sock: socket, page: query["page"]};
 217     socket.on("message", messageListener);
 218     socket.on("close", closeListener);
 219   });
 220 }