server/sockets.js

   1 const Discord = require('discord.js');
   2 const { token, channel } = require('./config/discord.json');
   3
   4 // Node version in Ubuntu 16.04 does not know about URL class
   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   const discordClient = new Discord.Client();
  31   let discordChannel = null;
  32   if (token.length > 0) {
  33     discordClient.login(token).then( () => {
  34       discordChannel = discordClient.channels.cache.get(channel);
  35     });
  36   }
  37   wss.on("connection", (socket, req) => {
  38     const query = getJsonFromUrl(req.url);
  39     const sid = query["sid"];
  40     const id = query["id"];
  41     const tmpId = query["tmpId"];
  42     const page = query["page"];
  43     const notifyRoom = (page, code, obj={}, except) => {
  44       if (!clients[page]) return;
  45       except = except || [];
  46       Object.keys(clients[page]).forEach(k => {
  47         if (except.includes(k)) return;
  48         Object.keys(clients[page][k]).forEach(x => {
  49           if (k == sid && x == tmpId) return;
  50           send(
  51             clients[page][k][x].socket,
  52             Object.assign({ code: code, from: [sid, tmpId] }, obj)
  53           );
  54         });
  55       });
  56     };
  57     const deleteConnexion = () => {
  58       if (!clients[page] || !clients[page][sid] || !clients[page][sid][tmpId])
  59         return; //job already done
  60       delete clients[page][sid][tmpId];
  61       if (Object.keys(clients[page][sid]).length == 0) {
  62         delete clients[page][sid];
  63         const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
  64         sidToPages[sid].splice(pgIndex, 1);
  65         if (Object.keys(clients[page]).length == 0)
  66           delete clients[page];
  67         // Am I totally offline?
  68         if (sidToPages[sid].length == 0) {
  69           delete sidToPages[sid];
  70           delete idToSid[id];
  71         }
  72       }
  73     };
  74
  75     const doDisconnect = () => {
  76       deleteConnexion();
  77       // Nothing to notify when disconnecting from MyGames page:
  78       if (page != "/mygames") {
  79         notifyRoom(page, "disconnect");
  80         if (page.indexOf("/game/") >= 0)
  81           notifyRoom("/", "gdisconnect", { page: page });
  82       }
  83     };
  84     const messageListener = (objtxt) => {
  85       let obj = JSON.parse(objtxt);
  86       switch (obj.code) {
  87         // Wait for "connect" message to notify connection to the room,
  88         // because if game loading is slow the message listener might
  89         // not be ready too early.
  90         case "connect": {
  91           notifyRoom(page, "connect");
  92           if (page.indexOf("/game/") >= 0)
  93             notifyRoom("/", "gconnect", { page: page });
  94           break;
  95         }
  96         case "disconnect":
  97           // When page changes:
  98           doDisconnect();
  99           break;
 100         case "pollclients": {
 101           // From Game
 102           let sockIds = {};
 103           Object.keys(clients[page]).forEach(k => {
 104             sockIds[k] = {};
 105             Object.keys(clients[page][k]).forEach(x => {
 106               // Avoid polling my tmpId: no information to get
 107               if (k != sid || x != tmpId)
 108                 sockIds[k][x] = { focus: clients[page][k][x].focus };
 109             });
 110           });
 111           send(socket, { code: "pollclients", sockIds: sockIds });
 112           break;
 113         }
 114         case "pollclientsandgamers": {
 115           // From Hall
 116           let sockIds = {};
 117           Object.keys(clients["/"]).forEach(k => {
 118             sockIds[k] = {};
 119             Object.keys(clients[page][k]).forEach(x => {
 120               // Avoid polling my tmpId: no information to get
 121               if (k != sid || x != tmpId) {
 122                 sockIds[k][x] = {
 123                   page: "/",
 124                   focus: clients[page][k][x].focus
 125                 };
 126               }
 127             });
 128           });
 129           // NOTE: a "gamer" could also just be an observer
 130           Object.keys(clients).forEach(p => {
 131             if (p.indexOf("/game/") >= 0) {
 132               Object.keys(clients[p]).forEach(k => {
 133                 if (!sockIds[k]) sockIds[k] = {};
 134                 Object.keys(clients[p][k]).forEach(x => {
 135                   if (k != sid || x != tmpId) {
 136                     sockIds[k][x] = {
 137                       page: p,
 138                       focus: clients[p][k][x].focus
 139                     };
 140                   }
 141                 });
 142               });
 143             }
 144           });
 145           send(socket, { code: "pollclientsandgamers", sockIds: sockIds });
 146           break;
 147         }
 148
 149         // Asking something: from is fully identified,
 150         // but the requested resource can be from any tmpId (except current!)
 151         case "askidentity":
 152         case "asklastate":
 153         case "askchallenges":
 154         case "askgame": {
 155           const pg = obj.page || page; //required for askidentity and askgame
 156           if (!!clients[pg] && !!clients[pg][obj.target]) {
 157             let tmpIds = Object.keys(clients[pg][obj.target]);
 158             if (obj.target == sid) {
 159               // Targetting myself
 160               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 161               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 162             }
 163             if (tmpIds.length > 0) {
 164               const ttmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 165               send(
 166                 clients[pg][obj.target][ttmpId].socket,
 167                 { code: obj.code, from: [sid,tmpId,page] }
 168               );
 169             }
 170           }
 171           break;
 172         }
 173
 174         // Special situation of the previous "case":
 175         // Full game can be asked to any observer.
 176         case "askfullgame": {
 177           if (!!clients[page]) {
 178             let sids = Object.keys(clients[page]).filter(k => k != sid);
 179             if (sids.length > 0) {
 180               // Pick a SID at random in this set, and ask full game:
 181               const rid = sids[Math.floor(Math.random() * sids.length)];
 182               // ..to a random tmpId:
 183               const tmpIds = Object.keys(clients[page][rid]);
 184               const rtmpId = tmpIds[Math.floor(Math.random() * tmpIds.length)];
 185               send(
 186                 clients[page][rid][rtmpId].socket,
 187                 { code: "askfullgame", from: [sid,tmpId] }
 188               );
 189             } else {
 190               // I'm the only person who have the game for the moment:
 191               send(socket, { code: "fullgame", data: { empty: true } });
 192             }
 193           }
 194           break;
 195         }
 196
 197         // Some Hall events: target all tmpId's (except mine),
 198         case "refusechallenge":
 199         case "startgame":
 200           Object.keys(clients[page][obj.target]).forEach(x => {
 201             if (obj.target != sid || x != tmpId)
 202               send(
 203                 clients[page][obj.target][x].socket,
 204                 { code: obj.code, data: obj.data }
 205               );
 206           });
 207           break;
 208
 209         // Notify all room: mostly game events
 210         case "newchat":
 211         case "newchallenge":
 212         case "deletechallenge_s":
 213         case "newgame":
 214         case "resign":
 215         case "abort":
 216         case "drawoffer":
 217         case "rematchoffer":
 218         case "draw":
 219           // "newgame" message can provide a page (corr Game --> Hall)
 220           notifyRoom(
 221             obj.page || page, obj.code, {data: obj.data}, obj.excluded);
 222           if (!!discordChannel && obj.code == "newchallenge") {
 223             discordChannel.send("New challenge: " +
 224               obj.data.vname +
 225               " [" + obj.data.cadence + "]" +
 226               " - https://vchess.club");
 227           }
 228           break;
 229
 230         case "rnewgame":
 231           // A rematch game started:
 232           notifyRoom(page, "newgame", {data: obj.data});
 233           // Explicitely notify Hall if gametype == corr.
 234           // Live games will be polled from Hall after gconnect event.
 235           if (obj.data.cadence.indexOf('d') >= 0)
 236             notifyRoom("/", "newgame", {data: obj.data});
 237           break;
 238
 239         case "newmove": {
 240           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 241           // Special case re-send newmove only to opponent:
 242           if (!!obj.target && !!clients[page][obj.target]) {
 243             Object.keys(clients[page][obj.target]).forEach(x => {
 244               send(
 245                 clients[page][obj.target][x].socket,
 246                 Object.assign({ code: "newmove" }, dataWithFrom)
 247               );
 248             });
 249           } else {
 250             // NOTE: data.from is useful only to opponent
 251             notifyRoom(page, "newmove", dataWithFrom);
 252           }
 253           break;
 254         }
 255         case "gotmove":
 256           if (
 257             !!clients[page][obj.target[0]] &&
 258             !!clients[page][obj.target[0]][obj.target[1]]
 259           ) {
 260             send(
 261               clients[page][obj.target[0]][obj.target[1]].socket,
 262               { code: "gotmove" }
 263             );
 264           }
 265           break;
 266
 267         case "result":
 268           // Special case: notify all, 'transroom': Game --> Hall
 269           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 270           break;
 271
 272         case "mabort": {
 273           const gamePg = "/game/" + obj.gid;
 274           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 275             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 276               send(
 277                 clients[gamePg][obj.target][x].socket,
 278                 { code: "abort" }
 279               );
 280             });
 281           }
 282           break;
 283         }
 284
 285         case "notifyscore":
 286         case "notifyturn":
 287         case "notifynewgame":
 288           if (!!clients["/mygames"]) {
 289             obj.targets.forEach(t => {
 290               const k = t.sid || idToSid[t.id];
 291               if (!!clients["/mygames"][k]) {
 292                 Object.keys(clients["/mygames"][k]).forEach(x => {
 293                   send(
 294                     clients["/mygames"][k][x].socket,
 295                     { code: obj.code, data: obj.data }
 296                   );
 297                 });
 298               }
 299             });
 300           }
 301           break;
 302
 303         case "getfocus":
 304         case "losefocus":
 305           if (
 306             !!clients[page] &&
 307             !!clients[page][sid] &&
 308             !!clients[page][sid][tmpId]
 309           ) {
 310             clients[page][sid][tmpId].focus = (obj.code == "getfocus");
 311           }
 312           if (page == "/") notifyRoom("/", obj.code, { page: "/" }, [sid]);
 313           else {
 314             // Notify game room + Hall:
 315             notifyRoom(page, obj.code, {}, [sid]);
 316             notifyRoom("/", obj.code, { page: page }, [sid]);
 317           }
 318           break;
 319
 320         // Passing, relaying something: from isn't needed,
 321         // but target is fully identified (sid + tmpId)
 322         case "challenges":
 323         case "fullgame":
 324         case "game":
 325         case "identity":
 326         case "lastate":
 327         {
 328           const pg = obj.target[2] || page; //required for identity and game
 329           // NOTE: if in game we ask identity to opponent still in Hall, but
 330           // leaving Hall, clients[pg] or clients[pg][target] could be undef.
 331           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 332             send(
 333               clients[pg][obj.target[0]][obj.target[1]].socket,
 334               { code:obj.code, data:obj.data }
 335             );
 336           }
 337           break;
 338         }
 339       }
 340     };
 341     const closeListener = () => {
 342       // For browser or tab closing (including page reload):
 343       doDisconnect();
 344     };
 345     // Update clients object: add new connexion
 346     const newElt = { socket: socket, focus: true };
 347     if (!clients[page])
 348       clients[page] = { [sid]: {[tmpId]: newElt } };
 349     else if (!clients[page][sid])
 350       clients[page][sid] = { [tmpId]: newElt };
 351     else
 352       clients[page][sid][tmpId] = newElt;
 353     // Also update helper correspondances
 354     if (!idToSid[id]) idToSid[id] = sid;
 355     if (!sidToPages[sid]) sidToPages[sid] = [];
 356     const pgIndex = sidToPages[sid].findIndex(pg => pg == page);
 357     if (pgIndex === -1) sidToPages[sid].push(page);
 358     socket.on("message", messageListener);
 359     socket.on("close", closeListener);
 360   });
 361 }