server/sockets.js

   1 // Node version in Ubuntu 16.04 does not know about URL class
   2 function getJsonFromUrl(url) {
   3   const query = url.substr(2); //starts with "/?"
   4   let result = {};
   5   query.split("&").forEach((part) => {
   6     const item = part.split("=");
   7     result[item[0]] = decodeURIComponent(item[1]);
   8   });
   9   return result;
  10 }
  11
  12 // Helper to safe-send some message through a (web-)socket:
  13 function send(socket, message) {
  14   if (!!socket && socket.readyState == 1)
  15     socket.send(JSON.stringify(message));
  16 }
  17
  18 module.exports = function(wss) {
  19   // Associative array page --> sid --> tmpId --> socket
  20   // "page" is either "/" for hall or "/game/some_gid" for Game,
  21   // or "/mygames" for Mygames page (simpler: no 'people' array).
  22   // tmpId is required if a same user (browser) has different tabs
  23   let clients = {};
  24   // NOTE: only purpose of sidToPages = know when to delete keys in idToSid
  25   let sidToPages = {};
  26   let idToSid = {};
  27   wss.on("connection", (socket, req) => {
  28     const query = getJsonFromUrl(req.url);
  29     const sid = query["sid"];
  30     const id = query["id"];
  31     const tmpId = query["tmpId"];
  32     const page = query["page"];
  33     const notifyRoom = (page, code, obj={}, except) => {
  34       if (!clients[page]) return;
  35       except = except || [];
  36       Object.keys(clients[page]).forEach(k => {
  37         if (except.includes(k)) return;
  38         Object.keys(clients[page][k]).forEach(x => {
  39           if (k == sid && x == tmpId) return;
  40           send(
  41             clients[page][k][x].socket,
  42             Object.assign({ code: code, from: [sid, tmpId] }, obj)
  43           );
  44         });
  45       });
  46     };
  47     const deleteConnexion = () => {
  48       if (!clients[page] || !clients[page][sid] || !clients[page][sid][tmpId])
  49         return; //job already done
  50       delete clients[page][sid][tmpId];
  51       if (Object.keys(clients[page][sid]).length == 0) {
  52         delete clients[page][sid];
  53         const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
  54         sidToPages[sid].splice(pgIndex, 1);
  55         if (Object.keys(clients[page]).length == 0)
  56           delete clients[page];
  57         // Am I totally offline?
  58         if (sidToPages[sid].length == 0) {
  59           delete sidToPages[sid];
  60           delete idToSid[id];
  61         }
  62       }
  63     };
  64
  65     const doDisconnect = () => {
  66       deleteConnexion();
  67       // Nothing to notify when disconnecting from MyGames page:
  68       if (page != "/mygames") {
  69         notifyRoom(page, "disconnect");
  70         if (page.indexOf("/game/") >= 0)
  71           notifyRoom("/", "gdisconnect", { page: page });
  72       }
  73     };
  74     const messageListener = (objtxt) => {
  75       let obj = JSON.parse(objtxt);
  76       switch (obj.code) {
  77         // Wait for "connect" message to notify connection to the room,
  78         // because if game loading is slow the message listener might
  79         // not be ready too early.
  80         case "connect": {
  81           notifyRoom(page, "connect");
  82           if (page.indexOf("/game/") >= 0)
  83             notifyRoom("/", "gconnect", { page: page });
  84           break;
  85         }
  86         case "disconnect":
  87           // When page changes:
  88           doDisconnect();
  89           break;
  90         case "pollclients": {
  91           // From Game
  92           let sockIds = {};
  93           Object.keys(clients[page]).forEach(k => {
  94             sockIds[k] = {};
  95             Object.keys(clients[page][k]).forEach(x => {
  96               // Avoid polling my tmpId: no information to get
  97               if (k != sid || x != tmpId)
  98                 sockIds[k][x] = { focus: clients[page][k][x].focus };
  99             });
 100           });
 101           send(socket, { code: "pollclients", sockIds: sockIds });
 102           break;
 103         }
 104         case "pollclientsandgamers": {
 105           // From Hall
 106           let sockIds = {};
 107           Object.keys(clients["/"]).forEach(k => {
 108             sockIds[k] = {};
 109             Object.keys(clients[page][k]).forEach(x => {
 110               // Avoid polling my tmpId: no information to get
 111               if (k != sid || x != tmpId) {
 112                 sockIds[k][x] = {
 113                   page: "/",
 114                   focus: clients[page][k][x].focus
 115                 };
 116               }
 117             });
 118           });
 119           // NOTE: a "gamer" could also just be an observer
 120           Object.keys(clients).forEach(p => {
 121             if (p.indexOf("/game/") >= 0) {
 122               Object.keys(clients[p]).forEach(k => {
 123                 if (!sockIds[k]) sockIds[k] = {};
 124                 Object.keys(clients[p][k]).forEach(x => {
 125                   if (k != sid || x != tmpId) {
 126                     sockIds[k][x] = {
 127                       page: p,
 128                       focus: clients[p][k][x].focus
 129                     };
 130                   }
 131                 });
 132               });
 133             }
 134           });
 135           send(socket, { code: "pollclientsandgamers", sockIds: sockIds });
 136           break;
 137         }
 138
 139         // Asking something: from is fully identified,
 140         // but the requested resource can be from any tmpId (except current!)
 141         case "askidentity":
 142         case "asklastate":
 143         case "askchallenges":
 144         case "askgame": {
 145           const pg = obj.page || page; //required for askidentity and askgame
 146           if (!!clients[pg] && !!clients[pg][obj.target]) {
 147             let tmpIds = Object.keys(clients[pg][obj.target]);
 148             if (obj.target == sid) {
 149               // Targetting myself
 150               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 151               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 152             }
 153             if (tmpIds.length > 0) {
 154               const ttmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 155               send(
 156                 clients[pg][obj.target][ttmpId].socket,
 157                 { code: obj.code, from: [sid,tmpId,page] }
 158               );
 159             }
 160           }
 161           break;
 162         }
 163
 164         // Special situation of the previous "case":
 165         // Full game can be asked to any observer.
 166         case "askfullgame": {
 167           if (!!clients[page]) {
 168             let sids = Object.keys(clients[page]).filter(k => k != sid);
 169             if (sids.length > 0) {
 170               // Pick a SID at random in this set, and ask full game:
 171               const rid = sids[Math.floor(Math.random() * sids.length)];
 172               // ..to a random tmpId:
 173               const tmpIds = Object.keys(clients[page][rid]);
 174               const rtmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 175               send(
 176                 clients[page][rid][rtmpId].socket,
 177                 { code: "askfullgame", from: [sid,tmpId] }
 178               );
 179             } else {
 180               // I'm the only person who have the game for the moment:
 181               send(socket, { code: "fullgame", data: { empty: true } });
 182             }
 183           }
 184           break;
 185         }
 186
 187         // Some Hall events: target all tmpId's (except mine),
 188         case "refusechallenge":
 189         case "startgame":
 190           Object.keys(clients[page][obj.target]).forEach(x => {
 191             if (obj.target != sid || x != tmpId)
 192               send(
 193                 clients[page][obj.target][x].socket,
 194                 { code: obj.code, data: obj.data }
 195               );
 196           });
 197           break;
 198
 199         // Notify all room: mostly game events
 200         case "newchat":
 201         case "newchallenge":
 202         case "deletechallenge_s":
 203         case "newgame":
 204         case "resign":
 205         case "abort":
 206         case "drawoffer":
 207         case "rematchoffer":
 208         case "draw":
 209           // "newgame" message can provide a page (corr Game --> Hall)
 210           notifyRoom(
 211             obj.page || page, obj.code, {data: obj.data}, obj.excluded);
 212           break;
 213
 214         case "rnewgame":
 215           // A rematch game started:
 216           notifyRoom(page, "newgame", {data: obj.data});
 217           // Explicitely notify Hall if gametype == corr.
 218           // Live games will be polled from Hall after gconnect event.
 219           if (obj.data.cadence.indexOf('d') >= 0)
 220             notifyRoom("/", "newgame", {data: obj.data});
 221           break;
 222
 223         case "newmove": {
 224           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 225           // Special case re-send newmove only to opponent:
 226           if (!!obj.target && !!clients[page][obj.target]) {
 227             Object.keys(clients[page][obj.target]).forEach(x => {
 228               send(
 229                 clients[page][obj.target][x].socket,
 230                 Object.assign({ code: "newmove" }, dataWithFrom)
 231               );
 232             });
 233           } else {
 234             // NOTE: data.from is useful only to opponent
 235             notifyRoom(page, "newmove", dataWithFrom);
 236           }
 237           break;
 238         }
 239         case "gotmove":
 240           if (
 241             !!clients[page][obj.target[0]] &&
 242             !!clients[page][obj.target[0]][obj.target[1]]
 243           ) {
 244             send(
 245               clients[page][obj.target[0]][obj.target[1]].socket,
 246               { code: "gotmove" }
 247             );
 248           }
 249           break;
 250
 251         case "result":
 252           // Special case: notify all, 'transroom': Game --> Hall
 253           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 254           break;
 255
 256         case "mabort": {
 257           const gamePg = "/game/" + obj.gid;
 258           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 259             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 260               send(
 261                 clients[gamePg][obj.target][x].socket,
 262                 { code: "abort" }
 263               );
 264             });
 265           }
 266           break;
 267         }
 268
 269         case "notifyscore":
 270         case "notifyturn":
 271         case "notifynewgame":
 272           if (!!clients["/mygames"]) {
 273             obj.targets.forEach(t => {
 274               const k = t.sid || idToSid[t.id];
 275               if (!!clients["/mygames"][k]) {
 276                 Object.keys(clients["/mygames"][k]).forEach(x => {
 277                   send(
 278                     clients["/mygames"][k][x].socket,
 279                     { code: obj.code, data: obj.data }
 280                   );
 281                 });
 282               }
 283             });
 284           }
 285           break;
 286
 287         case "getfocus":
 288         case "losefocus":
 289           if (
 290             !!clients[page] &&
 291             !!clients[page][sid] &&
 292             !!clients[page][sid][tmpId]
 293           ) {
 294             clients[page][sid][tmpId].focus = (obj.code == "getfocus");
 295           }
 296           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 297           else {
 298             // Notify game room + Hall:
 299             notifyRoom(page, obj.code, {}, [sid]);
 300             notifyRoom("/", obj.code, { page: page }, [sid]);
 301           }
 302           break;
 303
 304         // Passing, relaying something: from isn't needed,
 305         // but target is fully identified (sid + tmpId)
 306         case "challenges":
 307         case "fullgame":
 308         case "game":
 309         case "identity":
 310         case "lastate":
 311         {
 312           const pg = obj.target[2] || page; //required for identity and game
 313           // NOTE: if in game we ask identity to opponent still in Hall, but
 314           // leaving Hall, clients[pg] or clients[pg][target] could be undef.
 315           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 316             send(
 317               clients[pg][obj.target[0]][obj.target[1]].socket,
 318               { code:obj.code, data:obj.data }
 319             );
 320           }
 321           break;
 322         }
 323       }
 324     };
 325     const closeListener = () => {
 326       // For browser or tab closing (including page reload):
 327       doDisconnect();
 328     };
 329     // Update clients object: add new connexion
 330     const newElt = { socket: socket, focus: true };
 331     if (!clients[page])
 332       clients[page] = { [sid]: {[tmpId]: newElt } };
 333     else if (!clients[page][sid])
 334       clients[page][sid] = { [tmpId]: newElt };
 335     else
 336       clients[page][sid][tmpId] = newElt;
 337     // Also update helper correspondances
 338     if (!idToSid[id]) idToSid[id] = sid;
 339     if (!sidToPages[sid]) sidToPages[sid] = [];
 340     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 341     if (pgIndex === -1) sidToPages[sid].push(page);
 342     socket.on("message", messageListener);
 343     socket.on("close", closeListener);
 344   });
 345 }