sockets.js

   1 const message = require("./public/javascripts/utils/socketMessages");
   2 const params = require("./config/parameters");
   3 const AssessmentEntity = require("./entities/assessment");
   4 const ObjectId = require("bson-objectid");
   5
   6 // TODO: when teacher connect on monitor, io.of("appropriate namespace").on(connect student) { ... }
   7 // --> 2 sockets on monitoring page: one with ns "/" et one dedicated to the exam, triggered after the first
   8 // --> The monitoring page should not be closed during exam (otherwise monitors won't receive any more data)
   9
  10 function examRoom(socket) {
  11     let students = { };
  12     const aid = ObjectId(socket.handshake.query.aid);
  13
  14     // Student or monitor stuff
  15     const isTeacher = !!socket.handshake.query.secret && socket.handshake.query.secret == params.secret;
  16
  17     if (isTeacher)
  18     {
  19         socket.on(message.newAnswer, m => { //got answer from student
  20             socket.emit(message.newAnswer, m);
  21         });
  22         socket.on(message.allAnswers, m => { //send feedback to student (answers)
  23             if (!!students[m.number]) //TODO: namespace here... room quiz
  24                 socket.broadcast.to(students[m.number]).emit(message.allAnswers, m);
  25         });
  26         socket.on("disconnect", m => {
  27             // Reset student array if no more active teacher connections (TODO: condition)
  28             students = { };
  29         });
  30     }
  31
  32     else //student
  33     {
  34         const number = socket.handshake.query.number;
  35         const password = socket.handshake.query.password;
  36         AssessmentEntity.checkPassword(aid, number, password, (err,ret) => {
  37             if (!!err || !ret)
  38                 return; //wrong password, or some unexpected error...
  39             // Prevent socket connection (just ignore) if student already connected
  40             if (!!students[number])
  41                 return;
  42             students[number] = {
  43                 sid: socket.id,
  44                 password: password,
  45             };
  46             socket.on(message.allAnswers, () => { //got all answers from teacher
  47                 socket.emit(message.allAnswers, m);
  48             });
  49             socket.on("disconnect", () => {
  50                 // ..
  51                 //TODO: notify monitor (highlight red), redirect
  52             });
  53             // NOTE: nothing on disconnect --> teacher disconnect trigger students cleaning
  54         });
  55     }
  56 }
  57
  58 module.exports = function(io) {
  59
  60     // NOTE: if prof connected with 2 tabs and close 1, quizz should not break, thus following counter
  61     let namespaces = { };
  62
  63     io.of("/").on("connection", socketProf => {
  64         function closeQuizz(fullPath) {
  65             namespaces[fullPath].counter--;
  66             if (namespaces[fullPath].counter == 0)
  67             {
  68                 // https://stackoverflow.com/questions/26400595/socket-io-how-do-i-remove-a-namespace
  69                 const connectedSockets = Object.keys(namespaces[fullPath].nsp.connected);
  70                 connectedSockets.forEach( sid => {
  71                     namespaces[fullPath].nsp.connected[sid].disconnect();
  72                 });
  73                 namespaces[fullPath].nsp.removeAllListeners();
  74                 delete io.nsps[fullPath];
  75             }
  76         }
  77         // Only prof account can connect default namespace
  78         socketProf.on(message.startQuizz, m => {
  79             // m contient quizz ID + fullPath (initials+path+name)
  80             const quizzNamespace = io.of(m.fullPath);
  81             if (!namespaces[m.fullPath])
  82             {
  83                 namespaces[m.fullPath] = { nsp:quizzNamespace, counter:1 };
  84                 quizzNamespace.on("connection", quizzRoom); //après ça : prof can connect in quizz too
  85                 socketProf.emit(message.quizzReady);
  86                 socketProf.on(message.endQuizz, m2 => {
  87                     closeQuizz(m.fullPath);
  88                 });
  89                 socketProf.on("disconnect", m2 => {
  90                     closeQuizz(m.fullPath); //TODO: this should delete all students in array
  91                 });
  92             }
  93             else
  94                 namespaces[m.fullPath]++;
  95         });
  96     });
  97 }