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   // NOTE: only purpose of sidToPages = know when to delete keys in idToSid
  28   let sidToPages = {};
  29   let idToSid = {};
  30   wss.on("connection", (socket, req) => {
  31     const query = getJsonFromUrl(req.url);
  32     const sid = query["sid"];
  33     const id = query["id"];
  34     const tmpId = query["tmpId"];
  35     const page = query["page"];
  36     const notifyRoom = (page, code, obj={}, except) => {
  37       if (!clients[page]) return;
  38       except = except || [];
  39       Object.keys(clients[page]).forEach(k => {
  40         if (except.includes(k)) return;
  41         Object.keys(clients[page][k]).forEach(x => {
  42           if (k == sid && x == tmpId) return;
  43           send(
  44             clients[page][k][x].socket,
  45             Object.assign({ code: code, from: [sid, tmpId] }, obj)
  46           );
  47         });
  48       });
  49     };
  50     const deleteConnexion = () => {
  51       if (!clients[page] || !clients[page][sid] || !clients[page][sid][tmpId])
  52         return; //job already done
  53       delete clients[page][sid][tmpId];
  54       if (Object.keys(clients[page][sid]).length == 0) {
  55         delete clients[page][sid];
  56         const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
  57         sidToPages[sid].splice(pgIndex, 1);
  58         if (Object.keys(clients[page]).length == 0)
  59           delete clients[page];
  60         // Am I totally offline?
  61         if (sidToPages[sid].length == 0) {
  62           delete sidToPages[sid];
  63           delete idToSid[id];
  64         }
  65       }
  66     };
  67
  68     const doDisconnect = () => {
  69       deleteConnexion();
  70       // Nothing to notify when disconnecting from MyGames page:
  71       if (page != "/mygames") {
  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 Game
 125           let sockIds = {};
 126           Object.keys(clients[page]).forEach(k => {
 127             // Avoid polling myself: no new information to get
 128             if (k != sid) {
 129               sockIds[k] = {};
 130               Object.keys(clients[page][k]).forEach(x => {
 131                 sockIds[k][x] = { focus: clients[page][k][x].focus };
 132               });
 133             }
 134           });
 135           send(socket, { code: "pollclients", sockIds: sockIds });
 136           break;
 137         }
 138         case "pollclientsandgamers": {
 139           // From Hall
 140           let sockIds = {};
 141           Object.keys(clients["/"]).forEach(k => {
 142             // Avoid polling myself: no new information to get
 143             if (k != sid) {
 144               sockIds[k] = {};
 145               Object.keys(clients[page][k]).forEach(x => {
 146                 sockIds[k][x] = {
 147                   page: "/",
 148                   focus: clients[page][k][x].focus
 149                 };
 150               });
 151             }
 152           });
 153           // NOTE: a "gamer" could also just be an observer
 154           Object.keys(clients).forEach(p => {
 155             if (p.indexOf("/game/") >= 0) {
 156               Object.keys(clients[p]).forEach(k => {
 157                 if (k != sid) {
 158                   if (!sockIds[k]) sockIds[k] = {};
 159                   Object.keys(clients[p][k]).forEach(x => {
 160                     sockIds[k][x] = {
 161                       page: p,
 162                       focus: clients[p][k][x].focus
 163                     };
 164                   });
 165                 }
 166               });
 167             }
 168           });
 169           send(socket, { code: "pollclientsandgamers", sockIds: sockIds });
 170           break;
 171         }
 172
 173         // Asking something: from is fully identified,
 174         // but the requested resource can be from any tmpId (except current!)
 175         case "askidentity":
 176         case "asklastate":
 177         case "askchallenges":
 178         case "askgame": {
 179           const pg = obj.page || page; //required for askidentity and askgame
 180           if (!!clients[pg] && !!clients[pg][obj.target]) {
 181             let tmpIds = Object.keys(clients[pg][obj.target]);
 182             if (obj.target == sid) {
 183               // Targetting myself
 184               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 185               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 186             }
 187             if (tmpIds.length > 0) {
 188               const ttmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 189               send(
 190                 clients[pg][obj.target][ttmpId].socket,
 191                 { code: obj.code, from: [sid,tmpId,page] }
 192               );
 193             }
 194           }
 195           break;
 196         }
 197
 198         // Special situation of the previous "case":
 199         // Full game can be asked to any observer.
 200         case "askfullgame": {
 201           if (!!clients[page]) {
 202             let sids = Object.keys(clients[page]).filter(k => k != sid);
 203             if (sids.length > 0) {
 204               // Pick a SID at random in this set, and ask full game:
 205               const rid = sids[Math.floor(Math.random() * sids.length)];
 206               // ..to a random tmpId:
 207               const tmpIds = Object.keys(clients[page][rid]);
 208               const rtmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 209               send(
 210                 clients[page][rid][rtmpId].socket,
 211                 { code: "askfullgame", from: [sid,tmpId] }
 212               );
 213             }
 214           }
 215           break;
 216         }
 217
 218         // Some Hall events: target all tmpId's (except mine),
 219         case "refusechallenge":
 220         case "startgame":
 221           Object.keys(clients[page][obj.target]).forEach(x => {
 222             if (obj.target != sid || x != tmpId)
 223               send(
 224                 clients[page][obj.target][x].socket,
 225                 { code: obj.code, data: obj.data }
 226               );
 227           });
 228           break;
 229
 230         // Notify all room: mostly game events
 231         case "newchat":
 232         case "newchallenge":
 233         case "deletechallenge_s":
 234         case "newgame":
 235         case "resign":
 236         case "abort":
 237         case "drawoffer":
 238         case "rematchoffer":
 239         case "draw":
 240           // "newgame" message can provide a page (corr Game --> Hall)
 241           notifyRoom(obj.page || page, obj.code, {data: obj.data}, obj.excluded);
 242           break;
 243
 244         case "rnewgame":
 245           // A rematch game started:
 246           notifyRoom(page, "newgame", {data: obj.data});
 247           // Explicitely notify Hall if gametype == corr.
 248           // Live games will be polled from Hall after gconnect event.
 249           if (obj.data.cadence.indexOf('d') >= 0)
 250             notifyRoom("/", "newgame", {data: obj.data});
 251           break;
 252
 253         case "newmove": {
 254           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 255           // Special case re-send newmove only to opponent:
 256           if (!!obj.target && !!clients[page][obj.target]) {
 257             Object.keys(clients[page][obj.target]).forEach(x => {
 258               send(
 259                 clients[page][obj.target][x].socket,
 260                 Object.assign({ code: "newmove" }, dataWithFrom)
 261               );
 262             });
 263           } else {
 264             // NOTE: data.from is useful only to opponent
 265             notifyRoom(page, "newmove", dataWithFrom);
 266           }
 267           break;
 268         }
 269         case "gotmove":
 270           if (
 271             !!clients[page][obj.target[0]] &&
 272             !!clients[page][obj.target[0]][obj.target[1]]
 273           ) {
 274             send(
 275               clients[page][obj.target[0]][obj.target[1]].socket,
 276               { code: "gotmove" }
 277             );
 278           }
 279           break;
 280
 281         case "result":
 282           // Special case: notify all, 'transroom': Game --> Hall
 283           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 284           break;
 285
 286         case "mabort": {
 287           const gamePg = "/game/" + obj.gid;
 288           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 289             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 290               send(
 291                 clients[gamePg][obj.target][x].socket,
 292                 { code: "abort" }
 293               );
 294             });
 295           }
 296           break;
 297         }
 298
 299         case "notifyscore":
 300         case "notifyturn":
 301         case "notifynewgame":
 302           if (!!clients["/mygames"]) {
 303             obj.targets.forEach(t => {
 304               const k = t.sid || idToSid[t.id];
 305               if (!!clients["/mygames"][k]) {
 306                 Object.keys(clients["/mygames"][k]).forEach(x => {
 307                   send(
 308                     clients["/mygames"][k][x].socket,
 309                     { code: obj.code, data: obj.data }
 310                   );
 311                 });
 312               }
 313             });
 314           }
 315           break;
 316
 317         case "getfocus":
 318         case "losefocus":
 319           clients[page][sid][tmpId].focus = (obj.code == "getfocus");
 320           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 321           else {
 322             // Notify game room + Hall:
 323             notifyRoom(page, obj.code, {}, [sid]);
 324             notifyRoom("/", obj.code, { page: page }, [sid]);
 325           }
 326           break;
 327
 328         // Passing, relaying something: from isn't needed,
 329         // but target is fully identified (sid + tmpId)
 330         case "challenges":
 331         case "fullgame":
 332         case "game":
 333         case "identity":
 334         case "lastate":
 335         {
 336           const pg = obj.target[2] || page; //required for identity and game
 337           // NOTE: if in game we ask identity to opponent still in Hall,
 338           // but leaving Hall, clients[pg] or clients[pg][target] could be undefined
 339           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 340             send(
 341               clients[pg][obj.target[0]][obj.target[1]].socket,
 342               { code:obj.code, data:obj.data }
 343             );
 344           }
 345           break;
 346         }
 347       }
 348     };
 349     const closeListener = () => {
 350       // For browser or tab closing (including page reload):
 351       doDisconnect();
 352     };
 353     // Update clients object: add new connexion
 354     const newElt = { socket: socket, focus: true };
 355     if (!clients[page])
 356       clients[page] = { [sid]: {[tmpId]: newElt } };
 357     else if (!clients[page][sid])
 358       clients[page][sid] = { [tmpId]: newElt };
 359     else
 360       clients[page][sid][tmpId] = newElt;
 361     // Also update helper correspondances
 362     if (!idToSid[id]) idToSid[id] = sid;
 363     if (!sidToPages[sid]) sidToPages[sid] = [];
 364     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 365     if (pgIndex === -1) sidToPages[sid].push(page);
 366     socket.on("message", messageListener);
 367     socket.on("close", closeListener);
 368   });
 369 }