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   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 // Helper to safe-send some message through a (web-)socket:
  16 function send(socket, message) {
  17   if (!!socket && socket.readyState == 1)
  18     socket.send(JSON.stringify(message));
  19 }
  20
  21 module.exports = function(wss) {
  22   // Associative array page --> sid --> tmpId --> socket
  23   // "page" is either "/" for hall or "/game/some_gid" for Game,
  24   // or "/mygames" for Mygames page (simpler: no 'people' array).
  25   // tmpId is required if a same user (browser) has different tabs
  26   let clients = {};
  27   let sidToPages = {};
  28   let idToSid = {};
  29   wss.on("connection", (socket, req) => {
  30     const query = getJsonFromUrl(req.url);
  31     const sid = query["sid"];
  32     const id = query["id"];
  33     const tmpId = query["tmpId"];
  34     const page = query["page"];
  35     const notifyRoom = (page, code, obj={}, except) => {
  36       if (!clients[page]) return;
  37       except = except || [];
  38       Object.keys(clients[page]).forEach(k => {
  39         if (except.includes(k)) return;
  40         Object.keys(clients[page][k]).forEach(x => {
  41           if (k == sid && x == tmpId) return;
  42           send(
  43             clients[page][k][x].socket,
  44             Object.assign({ code: code, from: sid }, obj)
  45           );
  46         });
  47       });
  48     };
  49     const deleteConnexion = () => {
  50       if (!clients[page] || !clients[page][sid] || !clients[page][sid][tmpId])
  51         return; //job already done
  52       delete clients[page][sid][tmpId];
  53       if (Object.keys(clients[page][sid]).length == 0) {
  54         delete clients[page][sid];
  55         const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
  56         sidToPages[sid].splice(pgIndex, 1);
  57         if (Object.keys(clients[page]).length == 0)
  58           delete clients[page];
  59         // Am I totally offline?
  60         if (sidToPages[sid].length == 0) {
  61           delete sidToPages[sid];
  62           delete idToSid[id];
  63         }
  64       }
  65     };
  66
  67     const doDisconnect = () => {
  68       deleteConnexion();
  69       // Nothing to notify when disconnecting from MyGames page:
  70       if (page != "/mygames" && (!clients[page] || !clients[page][sid])) {
  71         // I effectively disconnected from this page:
  72         notifyRoom(page, "disconnect");
  73         if (page.indexOf("/game/") >= 0)
  74           notifyRoom("/", "gdisconnect", { page:page });
  75       }
  76     };
  77     const messageListener = (objtxt) => {
  78       let obj = JSON.parse(objtxt);
  79       switch (obj.code) {
  80         // Wait for "connect" message to notify connection to the room,
  81         // because if game loading is slow the message listener might
  82         // not be ready too early.
  83         case "connect": {
  84           notifyRoom(page, "connect");
  85           if (page.indexOf("/game/") >= 0)
  86             notifyRoom("/", "gconnect", { page:page });
  87           break;
  88         }
  89         case "disconnect":
  90           // When page changes:
  91           doDisconnect();
  92           break;
  93         case "killme": {
  94           // Self multi-connect: manual removal + disconnect
  95           const doKill = (pg) => {
  96             Object.keys(clients[pg][obj.sid]).forEach(x => {
  97               send(clients[pg][obj.sid][x].socket, { code: "killed" });
  98             });
  99             delete clients[pg][obj.sid];
 100           };
 101           const disconnectFromOtherConnexion = (pg,code,o={}) => {
 102             Object.keys(clients[pg]).forEach(k => {
 103               if (k != obj.sid) {
 104                 Object.keys(clients[pg][k]).forEach(x => {
 105                   send(
 106                     clients[pg][k][x].socket,
 107                     Object.assign({ code: code, from: obj.sid }, o)
 108                   );
 109                 });
 110               }
 111             });
 112           };
 113           Object.keys(clients).forEach(pg => {
 114             if (clients[pg][obj.sid]) {
 115               doKill(pg);
 116               disconnectFromOtherConnexion(pg, "disconnect");
 117               if (pg.indexOf("/game/") >= 0 && clients["/"])
 118                 disconnectFromOtherConnexion("/", "gdisconnect", { page: pg });
 119             }
 120           });
 121           break;
 122         }
 123         case "pollclients": {
 124           // From Hall or Game
 125           let sockIds = [];
 126           Object.keys(clients[page]).forEach(k => {
 127             // Avoid polling myself: no new information to get
 128             if (k != sid) sockIds.push(k);
 129           });
 130           send(socket, { code: "pollclients", sockIds: sockIds });
 131           break;
 132         }
 133         case "pollclientsandgamers": {
 134           // From Hall
 135           let sockIds = [];
 136           Object.keys(clients["/"]).forEach(k => {
 137             // Avoid polling myself: no new information to get
 138             if (k != sid) sockIds.push({sid:k});
 139           });
 140           // NOTE: a "gamer" could also just be an observer
 141           Object.keys(clients).forEach(p => {
 142             if (p.indexOf("/game/") >= 0) {
 143               Object.keys(clients[p]).forEach(k => {
 144                 // 'page' indicator is needed for gamers
 145                 if (k != sid) sockIds.push({ sid:k, page:p });
 146               });
 147             }
 148           });
 149           send(socket, { code: "pollclientsandgamers", sockIds: sockIds });
 150           break;
 151         }
 152
 153         // Asking something: from is fully identified,
 154         // but the requested resource can be from any tmpId (except current!)
 155         case "askidentity":
 156         case "asklastate":
 157         case "askchallenges":
 158         case "askgame":
 159         case "askfullgame": {
 160           const pg = obj.page || page; //required for askidentity and askgame
 161           // In cas askfullgame to wrong SID for example, would crash:
 162           if (!!clients[pg] && !!clients[pg][obj.target]) {
 163             const tmpIds = Object.keys(clients[pg][obj.target]);
 164             if (obj.target == sid) {
 165               // Targetting myself
 166               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 167               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 168             }
 169             const tmpId_idx = Math.floor(Math.random() * tmpIds.length);
 170             send(
 171               clients[pg][obj.target][tmpIds[tmpId_idx]].socket,
 172               { code: obj.code, from: [sid,tmpId,page] }
 173             );
 174           }
 175           break;
 176         }
 177
 178         // Some Hall events: target all tmpId's (except mine),
 179         case "refusechallenge":
 180         case "startgame":
 181           Object.keys(clients[page][obj.target]).forEach(x => {
 182             if (obj.target != sid || x != tmpId)
 183               send(
 184                 clients[page][obj.target][x].socket,
 185                 { code: obj.code, data: obj.data }
 186               );
 187           });
 188           break;
 189
 190         // Notify all room: mostly game events
 191         case "newchat":
 192         case "newchallenge":
 193         case "deletechallenge_s":
 194         case "newgame":
 195         case "resign":
 196         case "abort":
 197         case "drawoffer":
 198         case "rematchoffer":
 199         case "draw":
 200           notifyRoom(page, obj.code, {data: obj.data}, obj.excluded);
 201           break;
 202
 203         case "rnewgame":
 204           // A rematch game started:
 205           notifyRoom(page, "newgame", {data: obj.data});
 206           // Explicitely notify Hall if gametype == corr.
 207           // Live games will be polled from Hall after gconnect event.
 208           if (obj.data.cadence.indexOf('d') >= 0)
 209             notifyRoom("/", "newgame", {data: obj.data});
 210           break;
 211
 212         case "newmove": {
 213           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 214           // Special case re-send newmove only to opponent:
 215           if (!!obj.target && !!clients[page][obj.target]) {
 216             Object.keys(clients[page][obj.target]).forEach(x => {
 217               send(
 218                 clients[page][obj.target][x].socket,
 219                 Object.assign({ code: "newmove" }, dataWithFrom)
 220               );
 221             });
 222           } else {
 223             // NOTE: data.from is useful only to opponent
 224             notifyRoom(page, "newmove", dataWithFrom);
 225           }
 226           break;
 227         }
 228         case "gotmove":
 229           if (
 230             !!clients[page][obj.target[0]] &&
 231             !!clients[page][obj.target[0]][obj.target[1]]
 232           ) {
 233             send(
 234               clients[page][obj.target[0]][obj.target[1]].socket,
 235               { code: "gotmove" }
 236             );
 237           }
 238           break;
 239
 240         case "result":
 241           // Special case: notify all, 'transroom': Game --> Hall
 242           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 243           break;
 244
 245         case "mabort": {
 246           const gamePg = "/game/" + obj.gid;
 247           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 248             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 249               send(
 250                 clients[gamePg][obj.target][x].socket,
 251                 { code: "abort" }
 252               );
 253             });
 254           }
 255           break;
 256         }
 257
 258         case "notifyscore":
 259         case "notifyturn":
 260         case "notifynewgame":
 261           if (!!clients["/mygames"]) {
 262             obj.targets.forEach(t => {
 263               const k = t.sid || idToSid[t.id];
 264               if (!!clients["/mygames"][k]) {
 265                 Object.keys(clients["/mygames"][k]).forEach(x => {
 266                   send(
 267                     clients["/mygames"][k][x].socket,
 268                     { code: obj.code, data: obj.data }
 269                   );
 270                 });
 271               }
 272             });
 273           }
 274           break;
 275
 276         case "getfocus":
 277         case "losefocus":
 278           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 279           else {
 280             // Notify game room + Hall:
 281             notifyRoom(page, obj.code, {}, [sid]);
 282             notifyRoom("/", obj.code, { page: page }, [sid]);
 283           }
 284           break;
 285
 286         // Passing, relaying something: from isn't needed,
 287         // but target is fully identified (sid + tmpId)
 288         case "challenges":
 289         case "fullgame":
 290         case "game":
 291         case "identity":
 292         case "lastate":
 293         {
 294           const pg = obj.target[2] || page; //required for identity and game
 295           // NOTE: if in game we ask identity to opponent still in Hall,
 296           // but leaving Hall, clients[pg] or clients[pg][target] could be undefined
 297           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 298             send(
 299               clients[pg][obj.target[0]][obj.target[1]].socket,
 300               { code:obj.code, data:obj.data }
 301             );
 302           }
 303           break;
 304         }
 305       }
 306     };
 307     const closeListener = () => {
 308       // For browser or tab closing (including page reload):
 309       doDisconnect();
 310     };
 311     // Update clients object: add new connexion
 312     const newElt = { socket: socket, focus: true };
 313     if (!clients[page])
 314       clients[page] = { [sid]: {[tmpId]: newElt } };
 315     else if (!clients[page][sid])
 316       clients[page][sid] = { [tmpId]: newElt };
 317     else
 318       clients[page][sid][tmpId] = newElt;
 319     // Also update helper correspondances
 320     if (!idToSid[id]) idToSid[id] = sid;
 321     if (!sidToPages[sid]) sidToPages[sid] = [];
 322     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 323     if (pgIndex === -1) sidToPages[sid].push(page);
 324     socket.on("message", messageListener);
 325     socket.on("close", closeListener);
 326   });
 327 }