sockets.js

   1 const url = require('url');
   2 const sqlite3 = require('sqlite3');
   3 const db = new sqlite3.Database('db/vchess.sqlite');
   4
   5 // Node version in Ubuntu 16.04 does not know about URL class
   6 function getJsonFromUrl(url) {
   7     var query = url.substr(2); //starts with "/?"
   8     var result = {};
   9     query.split("&").forEach(function(part) {
  10         var item = part.split("=");
  11         result[item[0]] = decodeURIComponent(item[1]);
  12     });
  13     return result;
  14 }
  15
  16 module.exports = function(wss) {
  17     db.serialize(function() {
  18         db.all("SELECT * FROM Variants", (err,variants) => {
  19             let clients = { "index": {} };
  20             let games = {}; //pending games (player sid)
  21             for (const v of variants)
  22                 clients[v.name] = {};
  23             // No-op function as a callback when sending messages
  24             const noop = () => { };
  25             wss.on("connection", (socket, req) => {
  26 //              const params = new URL("http://localhost" + req.url).searchParams;
  27 //              const sid = params.get("sid");
  28 //              const page = params.get("page");
  29                 var query = getJsonFromUrl(req.url);
  30                 const sid = query["sid"];
  31                 const page = query["page"];
  32                 // Ignore duplicate connections:
  33                 if (!!clients[page][sid])
  34                 {
  35                     socket.send(JSON.stringify({code:"duplicate"}));
  36                     return;
  37                 }
  38                 clients[page][sid] = socket;
  39                 if (page == "index")
  40                 {
  41                     // Send counting info
  42                     const countings = {};
  43                     for (const v of variants)
  44                         countings[v.name] = Object.keys(clients[v.name]).length;
  45                     socket.send(JSON.stringify({code:"counts",counts:countings}));
  46                 }
  47                 else
  48                 {
  49                     // Send to every client connected on index an update message for counts
  50                     Object.keys(clients["index"]).forEach( k => {
  51                         clients["index"][k].send(
  52                             JSON.stringify({code:"increase",vname:page}), noop);
  53                     });
  54                     // Also notify potential opponents:
  55                     // hit all clients which check if sid corresponds
  56                     Object.keys(clients[page]).forEach( k => {
  57                         clients[page][k].send(JSON.stringify({code:"connect",id:sid}), noop);
  58                     });
  59                     socket.on("message", objtxt => {
  60                         let obj = JSON.parse(objtxt);
  61                         switch (obj.code)
  62                         {
  63                             case "newchat":
  64                                 if (!!clients[page][obj.oppid])
  65                                 {
  66                                     clients[page][obj.oppid].send(
  67                                         JSON.stringify({code:"newchat",msg:obj.msg}), noop);
  68                                 }
  69                                 break;
  70                             case "newmove":
  71                                 if (!!clients[page][obj.oppid])
  72                                 {
  73                                     clients[page][obj.oppid].send(
  74                                         JSON.stringify({code:"newmove",move:obj.move}), noop);
  75                                 }
  76                                 break;
  77                             case "ping":
  78                                 if (!!clients[page][obj.oppid])
  79                                     socket.send(JSON.stringify({code:"pong",gameId:obj.gameId}));
  80                                 break;
  81                             case "myname":
  82                                 // Reveal my username to opponent
  83                                 if (!!clients[page][obj.oppid])
  84                                 {
  85                                     clients[page][obj.oppid].send(JSON.stringify({
  86                                         code:"oppname", name:obj.name}));
  87                                 }
  88                                 break;
  89                             case "lastate":
  90                                 if (!!clients[page][obj.oppid])
  91                                 {
  92                                     const oppId = obj.oppid;
  93                                     obj.oppid = sid; //I'm oppid for my opponent
  94                                     clients[page][oppId].send(JSON.stringify(obj), noop);
  95                                 }
  96                                 break;
  97                             case "newgame":
  98                                 if (!!games[page])
  99                                 {
 100                                     // Start a new game
 101                                     const oppId = games[page]["id"];
 102                                     const fen = games[page]["fen"];
 103                                     delete games[page];
 104                                     const mycolor = Math.random() < 0.5 ? 'w' : 'b';
 105                                     socket.send(JSON.stringify(
 106                                         {code:"newgame",fen:fen,oppid:oppId,color:mycolor}));
 107                                     if (!!clients[page][oppId])
 108                                     {
 109                                         clients[page][oppId].send(
 110                                             JSON.stringify(
 111                                                 {code:"newgame",fen:fen,oppid:sid,color:mycolor=="w"?"b":"w"}),
 112                                             noop);
 113                                     }
 114                                 }
 115                                 else
 116                                     games[page] = {id:sid, fen:obj.fen}; //wait for opponent
 117                                 break;
 118                             case "cancelnewgame": //if a user cancel his seek
 119                                 delete games[page];
 120                                 break;
 121                             case "resign":
 122                                 if (!!clients[page][obj.oppid])
 123                                     clients[page][obj.oppid].send(JSON.stringify({code:"resign"}), noop);
 124                                 break;
 125                         }
 126                     });
 127                 }
 128                 socket.on("close", () => {
 129                     delete clients[page][sid];
 130                     // Remove potential pending game
 131                     if (!!games[page] && games[page]["id"] == sid)
 132                         delete games[page];
 133                     if (page != "index")
 134                     {
 135                         // Send to every client connected on index an update message for counts
 136                         Object.keys(clients["index"]).forEach( k => {
 137                             clients["index"][k].send(
 138                                 JSON.stringify({code:"decrease",vname:page}), noop);
 139                         });
 140                     }
 141                     // Also notify potential opponents:
 142                     // hit all clients which check if sid corresponds
 143                     Object.keys(clients[page]).forEach( k => {
 144                         clients[page][k].send(JSON.stringify({code:"disconnect",id:sid}), noop);
 145                     });
 146                 });
 147             });
 148         });
 149     });
 150 }