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   wss.on("connection", (socket, req) => {
  28     const query = getJsonFromUrl(req.url);
  29     const sid = query["sid"];
  30     const tmpId = query["tmpId"];
  31     const page = query["page"];
  32     const notifyRoom = (page,code,obj={}) => {
  33       if (!clients[page]) return;
  34       Object.keys(clients[page]).forEach(k => {
  35         Object.keys(clients[page][k]).forEach(x => {
  36           if (k == sid && x == tmpId) return;
  37           send(
  38             clients[page][k][x].socket,
  39             Object.assign({ code: code, from: sid }, obj)
  40           );
  41         });
  42       });
  43     };
  44     // For focus events: no need to target self
  45     const notifyAllBut = (page,code,obj={},except) => {
  46       if (!clients[page]) return;
  47       Object.keys(clients[page]).forEach(k => {
  48         if (except.includes(k)) return;
  49         Object.keys(clients[page][k]).forEach(x => {
  50           send(
  51             clients[page][k][x].socket,
  52             Object.assign({ code: code, from: sid }, 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         if (Object.keys(clients[page]).length == 0)
  64           delete clients[page];
  65       }
  66     };
  67
  68     const doDisconnect = () => {
  69       deleteConnexion();
  70       if (!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 != "/") {
 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 "askchallenge":
 158         case "askgame":
 159         case "askfullgame": {
 160           const pg = obj.page || page; //required for askidentity and askgame
 161           // In cas askfullgame to wrong SID for example, would crash:
 162           if (!!clients[pg] && !!clients[pg][obj.target]) {
 163             const tmpIds = Object.keys(clients[pg][obj.target]);
 164             if (obj.target == sid) {
 165               // Targetting myself
 166               const idx_myTmpid = tmpIds.findIndex(x => x == tmpId);
 167               if (idx_myTmpid >= 0) tmpIds.splice(idx_myTmpid, 1);
 168             }
 169             const tmpId_idx = Math.floor(Math.random() * tmpIds.length);
 170             send(
 171               clients[pg][obj.target][tmpIds[tmpId_idx]].socket,
 172               { code: obj.code, from: [sid,tmpId,page] }
 173             );
 174           }
 175           break;
 176         }
 177
 178         // Some Hall events: target all tmpId's (except mine),
 179         case "refusechallenge":
 180         case "startgame":
 181           Object.keys(clients[page][obj.target]).forEach(x => {
 182             if (obj.target != sid || x != tmpId)
 183               send(
 184                 clients[page][obj.target][x].socket,
 185                 { code: obj.code, data: obj.data }
 186               );
 187           });
 188           break;
 189
 190         // Notify all room: mostly game events
 191         case "newchat":
 192         case "newchallenge":
 193         case "deletechallenge":
 194         case "newgame":
 195         case "resign":
 196         case "abort":
 197         case "drawoffer":
 198         case "rematchoffer":
 199         case "draw":
 200           if (!!obj.oppsid)
 201             // "newgame" message from Hall: do not target players
 202             notifyAllBut(page, "newgame", {data: obj.data}, [sid, obj.oppsid]);
 203           else notifyRoom(page, obj.code, {data: obj.data});
 204           break;
 205
 206         case "rnewgame":
 207           // A rematch game started: players are already informed
 208           notifyAllBut(page, "newgame", {data: obj.data}, [sid]);
 209           notifyAllBut("/", "newgame", {data: obj.data}, [sid, obj.oppsid]);
 210           notifyRoom("/mygames", "newgame", {data: obj.data});
 211           break;
 212
 213         case "newmove": {
 214           const dataWithFrom = { from: [sid,tmpId], data: obj.data };
 215           // Special case re-send newmove only to opponent:
 216           if (!!obj.target && !!clients[page][obj.target]) {
 217             Object.keys(clients[page][obj.target]).forEach(x => {
 218               send(
 219                 clients[page][obj.target][x].socket,
 220                 Object.assign({ code: "newmove" }, dataWithFrom)
 221               );
 222             });
 223           } else {
 224             // NOTE: data.from is useful only to opponent
 225             notifyRoom(page, "newmove", dataWithFrom);
 226           }
 227           break;
 228         }
 229         case "gotmove":
 230           if (
 231             !!clients[page][obj.target[0]] &&
 232             !!clients[page][obj.target[0]][obj.target[1]]
 233           ) {
 234             send(
 235               clients[page][obj.target[0]][obj.target[1]].socket,
 236               { code: "gotmove" }
 237             );
 238           }
 239           break;
 240
 241         case "result":
 242           // Special case: notify all, 'transroom': Game --> Hall
 243           notifyRoom("/", "result", { gid: obj.gid, score: obj.score });
 244           break;
 245
 246         case "mconnect":
 247           // Special case: notify some game rooms that
 248           // I'm watching game state from MyGames
 249           // TODO: this code is ignored for now
 250           obj.gids.forEach(gid => {
 251             const pg = "/game/" + gid;
 252             Object.keys(clients[pg]).forEach(s => {
 253               Object.keys(clients[pg][s]).forEach(x => {
 254                 send(
 255                   clients[pg][s][x].socket,
 256                   { code: "mconnect", from: sid }
 257                 );
 258               });
 259             });
 260           });
 261           break;
 262         case "mdisconnect":
 263           // TODO
 264           // Also TODO: pass newgame to MyGames, and gameover (result)
 265           break;
 266         case "mabort": {
 267           const gamePg = "/game/" + obj.gid;
 268           if (!!clients[gamePg] && !!clients[gamePg][obj.target]) {
 269             Object.keys(clients[gamePg][obj.target]).forEach(x => {
 270               send(
 271                 clients[gamePg][obj.target][x].socket,
 272                 { code: "abort" }
 273               );
 274             });
 275           }
 276           break;
 277         }
 278
 279         case "getfocus":
 280         case "losefocus":
 281           if (page == "/") notifyAllBut("/", obj.code, { page: "/" }, [sid]);
 282           else {
 283             // Notify game room + Hall:
 284             notifyAllBut(page, obj.code, {}, [sid]);
 285             notifyAllBut("/", obj.code, { page: page }, [sid]);
 286           }
 287           break;
 288
 289         // Passing, relaying something: from isn't needed,
 290         // but target is fully identified (sid + tmpId)
 291         case "challenge":
 292         case "fullgame":
 293         case "game":
 294         case "identity":
 295         case "lastate":
 296         {
 297           const pg = obj.target[2] || page; //required for identity and game
 298           // NOTE: if in game we ask identity to opponent still in Hall,
 299           // but leaving Hall, clients[pg] or clients[pg][target] could be undefined
 300           if (!!clients[pg] && !!clients[pg][obj.target[0]]) {
 301             send(
 302               clients[pg][obj.target[0]][obj.target[1]].socket,
 303               { code:obj.code, data:obj.data }
 304             );
 305           }
 306           break;
 307         }
 308       }
 309     };
 310     const closeListener = () => {
 311       // For browser or tab closing (including page reload):
 312       doDisconnect();
 313     };
 314     // Update clients object: add new connexion
 315     const newElt = { socket: socket, focus: true };
 316     if (!clients[page])
 317       clients[page] = { [sid]: {[tmpId]: newElt } };
 318     else if (!clients[page][sid])
 319       clients[page][sid] = { [tmpId]: newElt };
 320     else
 321       clients[page][sid][tmpId] = newElt;
 322     socket.on("message", messageListener);
 323     socket.on("close", closeListener);
 324   });
 325 }