sockets.js

   1 //const url = require('url');
   2 const Variants = require("./variants");
   3
   4 function getJsonFromUrl(url) {
   5     var query = url.substr(2); //starts with "/?"
   6     var result = {};
   7     query.split("&").forEach(function(part) {
   8         var item = part.split("=");
   9         result[item[0]] = decodeURIComponent(item[1]);
  10     });
  11     return result;
  12 }
  13
  14 module.exports = function(wss) {
  15
  16     let clients = { "index": {} };
  17     let games = {}; //pending games (player sid)
  18     for (const v of Variants)
  19         clients[v.name] = {};
  20
  21     // (resign, newgame, newmove). See https://github.com/websockets/ws/blob/master/lib/websocket.js around line 313
  22     // TODO: awaiting newmove, resign, (+newgame?) :: in memory structure (use Redis ?)
  23     let newmoves = {};
  24     let newresign = {};
  25     for (const v of Variants)
  26     {
  27         newmoves[v.name] = {};
  28         newresign[v.name] = {};
  29     }
  30
  31     wss.on("connection", (socket, req) => {
  32         //const params = new URL("http://localhost" + req.url).searchParams;
  33         var query = getJsonFromUrl(req.url);
  34         const sid = query["sid"]; //params.get("sid");
  35         const page = query["page"]; //params.get("page");
  36         clients[page][sid] = socket;
  37         if (page == "index")
  38         {
  39             // Send counting info
  40             const countings = {};
  41             for (const v of Variants)
  42                 countings[v.name] = Object.keys(clients[v.name]).length;
  43             socket.send(JSON.stringify({code:"counts",counts:countings}));
  44         }
  45         else
  46         {
  47             // Send to every client connected on index an update message for counts
  48             Object.keys(clients["index"]).forEach( k => {
  49                 clients["index"][k].send(JSON.stringify({code:"increase",vname:page}));
  50             });
  51             // Also notify potential opponents: hit all clients which check if sid corresponds
  52             Object.keys(clients[page]).forEach( k => {
  53                 clients[page][k].send(JSON.stringify({code:"connect",id:sid}));
  54             });
  55             if (!!newmoves[page][sid])
  56             {
  57                 socket.send(JSON.stringify({code:"newmove",move:newmoves[page][sid]}));
  58                 delete newmoves[page][sid];
  59             }
  60             if (!!newresign[page][sid])
  61             {
  62                 socket.send(JSON.stringify({code:"resign"}));
  63                 delete newresign[page][sid];
  64             }
  65             socket.on("message", objtxt => {
  66                 let obj = JSON.parse(objtxt);
  67                 switch (obj.code)
  68                 {
  69                     case "newmove":
  70                         if (!!clients[page][obj.oppid] && clients[page][obj.oppid].readyState == WebSocket.OPEN)
  71                             clients[page][obj.oppid].send(JSON.stringify({code:"newmove",move:obj.move}));
  72                         else
  73                             newmoves[page][obj.oppid] = obj.move;
  74                         break;
  75                     case "ping":
  76                         if (!!clients[page][obj.oppid] && clients[page][obj.oppid].readyState == WebSocket.OPEN)
  77                             socket.send(JSON.stringify({code:"pong"}));
  78                         break;
  79                     case "newgame":
  80                         if (!!games[page])
  81                         {
  82                             // Start a new game
  83                             const oppId = games[page]["id"];
  84                             const fen = games[page]["fen"];
  85                             delete games[page];
  86                             const mycolor = Math.random() < 0.5 ? 'w' : 'b';
  87                             socket.send(JSON.stringify({code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
  88                             clients[page][oppId].send(JSON.stringify({code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}));
  89                         }
  90                         else
  91                             games[page] = {id:sid, fen:obj.fen}; //wait for opponent
  92                         break;
  93                     case "resign":
  94                         if (!!clients[page][obj.oppid] && clients[page][obj.oppid].readyState == WebSocket.OPEN)
  95                             clients[page][obj.oppid].send(JSON.stringify({code:"resign"}));
  96                         else
  97                             newresign[page][obj.oppid] = true;
  98                         break;
  99                 }
 100             });
 101         }
 102         socket.on("close", () => {
 103             delete clients[page][sid];
 104             // Remove potential pending game
 105             if (!!games[page] && games[page]["id"] == sid)
 106                 delete games[page];
 107             if (page != "index")
 108             {
 109                 // Send to every client connected on index an update message for counts
 110                 Object.keys(clients["index"]).forEach( k => {
 111                     clients["index"][k].send(JSON.stringify({code:"decrease",vname:page}));
 112                 });
 113             }
 114             // Also notify potential opponents: hit all clients which check if sid corresponds
 115             Object.keys(clients[page]).forEach( k => {
 116                 clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}));
 117             });
 118         });
 119     });
 120 }