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             sockIds[k] = {};
 128             Object.keys(clients[page][k]).forEach(x => {
 129               // Avoid polling my tmpId: no information to get
 130               if (k != sid || x != tmpId)
 131                 sockIds[k][x] = { focus: clients[page][k][x].focus };
 132             });
 133           });
 134           send(socket, { code: "pollclients", sockIds: sockIds });
 135           break;
 136         }
 137         case "pollclientsandgamers": {
 138           // From Hall
 139           let sockIds = {};
 140           Object.keys(clients["/"]).forEach(k => {
 141             sockIds[k] = {};
 142             Object.keys(clients[page][k]).forEach(x => {
 143               // Avoid polling my tmpId: no information to get
 144               if (k != sid || x != tmpId) {
 145                 sockIds[k][x] = {
 146                   page: "/",
 147                   focus: clients[page][k][x].focus
 148                 };
 149               }
 150             });
 151           });
 152           // NOTE: a "gamer" could also just be an observer
 153           Object.keys(clients).forEach(p => {
 154             if (p.indexOf("/game/") >= 0) {
 155               Object.keys(clients[p]).forEach(k => {
 156                 if (!sockIds[k]) sockIds[k] = {};
 157                 Object.keys(clients[p][k]).forEach(x => {
 158                   if (k != sid || x != tmpId) {
 159                     sockIds[k][x] = {
 160                       page: p,
 161                       focus: clients[p][k][x].focus
 162                     };
 163                   }
 164                 });
 165               });
 166             }
 167           });
 168           send(socket, { code: "pollclientsandgamers", sockIds: sockIds });
 169           break;
 170         }
 171
 172         // Asking something: from is fully identified,
 173         // but the requested resource can be from any tmpId (except current!)
 174         case "askidentity":
 175         case "asklastate":
 176         case "askchallenges":
 177         case "askgame": {
 178           const pg = obj.page || page; //required for askidentity and askgame
 179           if (!!clients[pg] && !!clients[pg][obj.target]) {
 180             let tmpIds = Object.keys(clients[pg][obj.target]);
 181             if (obj.target == sid) {
 182               // Targetting myself
 183               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 184               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 185             }
 186             if (tmpIds.length > 0) {
 187               const ttmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 188               send(
 189                 clients[pg][obj.target][ttmpId].socket,
 190                 { code: obj.code, from: [sid,tmpId,page] }
 191               );
 192             }
 193           }
 194           break;
 195         }
 196
 197         // Special situation of the previous "case":
 198         // Full game can be asked to any observer.
 199         case "askfullgame": {
 200           if (!!clients[page]) {
 201             let sids = Object.keys(clients[page]).filter(k => k != sid);
 202             if (sids.length > 0) {
 203               // Pick a SID at random in this set, and ask full game:
 204               const rid = sids[Math.floor(Math.random() * sids.length)];
 205               // ..to a random tmpId:
 206               const tmpIds = Object.keys(clients[page][rid]);
 207               const rtmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 208               send(
 209                 clients[page][rid][rtmpId].socket,
 210                 { code: "askfullgame", from: [sid,tmpId] }
 211               );
 212             } else {
 213               // I'm the only person who have the game for the moment:
 214               send(socket, { code: "fullgame", data: { empty: true } });
 215             }
 216           }
 217           break;
 218         }
 219
 220         // Some Hall events: target all tmpId's (except mine),
 221         case "refusechallenge":
 222         case "startgame":
 223           Object.keys(clients[page][obj.target]).forEach(x => {
 224             if (obj.target != sid || x != tmpId)
 225               send(
 226                 clients[page][obj.target][x].socket,
 227                 { code: obj.code, data: obj.data }
 228               );
 229           });
 230           break;
 231
 232         // Notify all room: mostly game events
 233         case "newchat":
 234         case "newchallenge":
 235         case "deletechallenge_s":
 236         case "newgame":
 237         case "resign":
 238         case "abort":
 239         case "drawoffer":
 240         case "rematchoffer":
 241         case "draw":
 242           // "newgame" message can provide a page (corr Game --> Hall)
 243           notifyRoom(
 244             obj.page || page, obj.code, {data: obj.data}, obj.excluded);
 245           break;
 246
 247         case "rnewgame":
 248           // A rematch game started:
 249           notifyRoom(page, "newgame", {data: obj.data});
 250           // Explicitely notify Hall if gametype == corr.
 251           // Live games will be polled from Hall after gconnect event.
 252           if (obj.data.cadence.indexOf('d') >= 0)
 253             notifyRoom("/", "newgame", {data: obj.data});
 254           break;
 255
 256         case "newmove": {
 257           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 258           // Special case re-send newmove only to opponent:
 259           if (!!obj.target && !!clients[page][obj.target]) {
 260             Object.keys(clients[page][obj.target]).forEach(x => {
 261               send(
 262                 clients[page][obj.target][x].socket,
 263                 Object.assign({ code: "newmove" }, dataWithFrom)
 264               );
 265             });
 266           } else {
 267             // NOTE: data.from is useful only to opponent
 268             notifyRoom(page, "newmove", dataWithFrom);
 269           }
 270           break;
 271         }
 272         case "gotmove":
 273           if (
 274             !!clients[page][obj.target[0]] &&
 275             !!clients[page][obj.target[0]][obj.target[1]]
 276           ) {
 277             send(
 278               clients[page][obj.target[0]][obj.target[1]].socket,
 279               { code: "gotmove" }
 280             );
 281           }
 282           break;
 283
 284         case "result":
 285           // Special case: notify all, 'transroom': Game --> Hall
 286           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 287           break;
 288
 289         case "mabort": {
 290           const gamePg = "/game/" + obj.gid;
 291           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 292             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 293               send(
 294                 clients[gamePg][obj.target][x].socket,
 295                 { code: "abort" }
 296               );
 297             });
 298           }
 299           break;
 300         }
 301
 302         case "notifyscore":
 303         case "notifyturn":
 304         case "notifynewgame":
 305           if (!!clients["/mygames"]) {
 306             obj.targets.forEach(t => {
 307               const k = t.sid || idToSid[t.id];
 308               if (!!clients["/mygames"][k]) {
 309                 Object.keys(clients["/mygames"][k]).forEach(x => {
 310                   send(
 311                     clients["/mygames"][k][x].socket,
 312                     { code: obj.code, data: obj.data }
 313                   );
 314                 });
 315               }
 316             });
 317           }
 318           break;
 319
 320         case "getfocus":
 321         case "losefocus":
 322           clients[page][sid][tmpId].focus = (obj.code == "getfocus");
 323           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 324           else {
 325             // Notify game room + Hall:
 326             notifyRoom(page, obj.code, {}, [sid]);
 327             notifyRoom("/", obj.code, { page: page }, [sid]);
 328           }
 329           break;
 330
 331         // Passing, relaying something: from isn't needed,
 332         // but target is fully identified (sid + tmpId)
 333         case "challenges":
 334         case "fullgame":
 335         case "game":
 336         case "identity":
 337         case "lastate":
 338         {
 339           const pg = obj.target[2] || page; //required for identity and game
 340           // NOTE: if in game we ask identity to opponent still in Hall, but
 341           // leaving Hall, clients[pg] or clients[pg][target] could be undef.
 342           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 343             send(
 344               clients[pg][obj.target[0]][obj.target[1]].socket,
 345               { code:obj.code, data:obj.data }
 346             );
 347           }
 348           break;
 349         }
 350       }
 351     };
 352     const closeListener = () => {
 353       // For browser or tab closing (including page reload):
 354       doDisconnect();
 355     };
 356     // Update clients object: add new connexion
 357     const newElt = { socket: socket, focus: true };
 358     if (!clients[page])
 359       clients[page] = { [sid]: {[tmpId]: newElt } };
 360     else if (!clients[page][sid])
 361       clients[page][sid] = { [tmpId]: newElt };
 362     else
 363       clients[page][sid][tmpId] = newElt;
 364     // Also update helper correspondances
 365     if (!idToSid[id]) idToSid[id] = sid;
 366     if (!sidToPages[sid]) sidToPages[sid] = [];
 367     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 368     if (pgIndex === -1) sidToPages[sid].push(page);
 369     socket.on("message", messageListener);
 370     socket.on("close", closeListener);
 371   });
 372 }