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           const pg = obj.page || page; //required for askidentity and askgame
 160           if (!!clients[pg] && !!clients[pg][obj.target]) {
 161             let tmpIds = Object.keys(clients[pg][obj.target]);
 162             if (obj.target == sid) {
 163               // Targetting myself
 164               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 165               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 166             }
 167             if (tmpIds.length > 0) {
 168               const ttmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 169               send(
 170                 clients[pg][obj.target][ttmpId].socket,
 171                 { code: obj.code, from: [sid,tmpId,page] }
 172               );
 173             }
 174           }
 175           break;
 176         }
 177
 178         // Special situation of the previous "case":
 179         // Full game can be asked to any observer.
 180         case "askfullgame": {
 181           if (!!clients[page]) {
 182             let sids = Object.keys(clients[page]).filter(k => k != sid);
 183             if (sids.length > 0) {
 184               // Pick a SID at random in this set, and ask full game:
 185               const rid = sids[Math.floor(Math.random() * sids.length)];
 186               // ..to a random tmpId:
 187               const tmpIds = Object.keys(clients[page][rid]);
 188               const rtmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 189               send(
 190                 clients[page][rid][rtmpId].socket,
 191                 { code: "askfullgame", from: [sid,tmpId] }
 192               );
 193             }
 194           }
 195           break;
 196         }
 197
 198         // Some Hall events: target all tmpId's (except mine),
 199         case "refusechallenge":
 200         case "startgame":
 201           Object.keys(clients[page][obj.target]).forEach(x => {
 202             if (obj.target != sid || x != tmpId)
 203               send(
 204                 clients[page][obj.target][x].socket,
 205                 { code: obj.code, data: obj.data }
 206               );
 207           });
 208           break;
 209
 210         // Notify all room: mostly game events
 211         case "newchat":
 212         case "newchallenge":
 213         case "deletechallenge_s":
 214         case "newgame":
 215         case "resign":
 216         case "abort":
 217         case "drawoffer":
 218         case "rematchoffer":
 219         case "draw":
 220           notifyRoom(page, obj.code, {data: obj.data}, obj.excluded);
 221           break;
 222
 223         case "rnewgame":
 224           // A rematch game started:
 225           notifyRoom(page, "newgame", {data: obj.data});
 226           // Explicitely notify Hall if gametype == corr.
 227           // Live games will be polled from Hall after gconnect event.
 228           if (obj.data.cadence.indexOf('d') >= 0)
 229             notifyRoom("/", "newgame", {data: obj.data});
 230           break;
 231
 232         case "newmove": {
 233           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 234           // Special case re-send newmove only to opponent:
 235           if (!!obj.target && !!clients[page][obj.target]) {
 236             Object.keys(clients[page][obj.target]).forEach(x => {
 237               send(
 238                 clients[page][obj.target][x].socket,
 239                 Object.assign({ code: "newmove" }, dataWithFrom)
 240               );
 241             });
 242           } else {
 243             // NOTE: data.from is useful only to opponent
 244             notifyRoom(page, "newmove", dataWithFrom);
 245           }
 246           break;
 247         }
 248         case "gotmove":
 249           if (
 250             !!clients[page][obj.target[0]] &&
 251             !!clients[page][obj.target[0]][obj.target[1]]
 252           ) {
 253             send(
 254               clients[page][obj.target[0]][obj.target[1]].socket,
 255               { code: "gotmove" }
 256             );
 257           }
 258           break;
 259
 260         case "result":
 261           // Special case: notify all, 'transroom': Game --> Hall
 262           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 263           break;
 264
 265         case "mabort": {
 266           const gamePg = "/game/" + obj.gid;
 267           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 268             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 269               send(
 270                 clients[gamePg][obj.target][x].socket,
 271                 { code: "abort" }
 272               );
 273             });
 274           }
 275           break;
 276         }
 277
 278         case "notifyscore":
 279         case "notifyturn":
 280         case "notifynewgame":
 281           if (!!clients["/mygames"]) {
 282             obj.targets.forEach(t => {
 283               const k = t.sid || idToSid[t.id];
 284               if (!!clients["/mygames"][k]) {
 285                 Object.keys(clients["/mygames"][k]).forEach(x => {
 286                   send(
 287                     clients["/mygames"][k][x].socket,
 288                     { code: obj.code, data: obj.data }
 289                   );
 290                 });
 291               }
 292             });
 293           }
 294           break;
 295
 296         case "getfocus":
 297         case "losefocus":
 298           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 299           else {
 300             // Notify game room + Hall:
 301             notifyRoom(page, obj.code, {}, [sid]);
 302             notifyRoom("/", obj.code, { page: page }, [sid]);
 303           }
 304           break;
 305
 306         // Passing, relaying something: from isn't needed,
 307         // but target is fully identified (sid + tmpId)
 308         case "challenges":
 309         case "fullgame":
 310         case "game":
 311         case "identity":
 312         case "lastate":
 313         {
 314           const pg = obj.target[2] || page; //required for identity and game
 315           // NOTE: if in game we ask identity to opponent still in Hall,
 316           // but leaving Hall, clients[pg] or clients[pg][target] could be undefined
 317           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 318             send(
 319               clients[pg][obj.target[0]][obj.target[1]].socket,
 320               { code:obj.code, data:obj.data }
 321             );
 322           }
 323           break;
 324         }
 325       }
 326     };
 327     const closeListener = () => {
 328       // For browser or tab closing (including page reload):
 329       doDisconnect();
 330     };
 331     // Update clients object: add new connexion
 332     const newElt = { socket: socket, focus: true };
 333     if (!clients[page])
 334       clients[page] = { [sid]: {[tmpId]: newElt } };
 335     else if (!clients[page][sid])
 336       clients[page][sid] = { [tmpId]: newElt };
 337     else
 338       clients[page][sid][tmpId] = newElt;
 339     // Also update helper correspondances
 340     if (!idToSid[id]) idToSid[id] = sid;
 341     if (!sidToPages[sid]) sidToPages[sid] = [];
 342     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 343     if (pgIndex === -1) sidToPages[sid].push(page);
 344     socket.on("message", messageListener);
 345     socket.on("close", closeListener);
 346   });
 347 }