Prevent student from re-starting the same quiz, implement resuming logic (still buggish)
authorBenjamin Auder <benjamin.auder@somewhere>
Sun, 28 Jan 2018 17:00:53 +0000 (18:00 +0100)
committerBenjamin Auder <benjamin.auder@somewhere>
Sun, 28 Jan 2018 17:00:53 +0000 (18:00 +0100)
entities/assessment.js
models/assessment.js
public/javascripts/assessment.js
routes/assessments.js
views/assessment.pug

index 2104193..a8a781b 100644 (file)
@@ -106,6 +106,25 @@ const AssessmentEntity =
                );
        },
 
+       getPaperByNumber: function(aid, number, callback)
+       {
+               db.assessments.findOne(
+                       {
+                               _id: aid,
+                               "papers.number": number,
+                       },
+                       (err,a) => {
+                               if (!!err || !a)
+                                       return callback(err,a);
+                               for (let p of a.papers)
+                               {
+                                       if (p.number == number)
+                                               return callback(null,p); //reached for sure
+                               }
+                       }
+               );
+       },
+
        startSession: function(aid, number, password, callback)
        {
                // TODO: security, do not re-do tasks if already done
@@ -123,6 +142,31 @@ const AssessmentEntity =
                );
        },
 
+
+       hasInput: function(aid, number, password, idx, cb)
+       {
+               db.assessments.findOne(
+                       {
+                               _id: aid,
+                               "papers.number": number,
+                               "papers.password": password,
+                       },
+                       (err,a) => {
+                               if (!!err || !a)
+                                       return cb(err,a);
+                               for (let p of a.papers)
+                               {
+                                       for (let i of p.inputs)
+                                       {
+                                               if (i.index == idx)
+                                                       return cb(null,true);
+                                       }
+                               }
+                               cb(null,false);
+                       }
+               );
+       },
+
        // https://stackoverflow.com/questions/27874469/mongodb-push-in-nested-array
        setInput: function(aid, number, password, input, callback) //input: index + arrayOfInt (or txt)
        {
index 3f89cc9..a1a41e2 100644 (file)
@@ -57,19 +57,52 @@ const AssessmentModel =
        },
 
        // Set password in responses collection
-       startSession: function(aid, number, cb)
+       startSession: function(aid, number, password, cb)
        {
-               const password = TokenGen.generate(12); //arbitrary number, 12 seems enough...
-               AssessmentEntity.getQuestions(aid, (err,questions) => {
-                       AssessmentEntity.startSession(aid, number, password, (err2,ret) => {
-                               cb(err, {
-                                       questions: questions,
-                                       password: password,
+               AssessmentEntity.getPaperByNumber(aid, number, (err,paper) => {
+                       if (!!err)
+                               return cb(err,null);
+                       if (!!paper)
+                       {
+                               if (!password)
+                                       return cb({errmsg:"Missing password"});
+                               if (paper.password != password)
+                                       return cb({errmsg:"Wrong password"});
+                       }
+                       AssessmentEntity.getQuestions(aid, (err,questions) => {
+                               if (!!err)
+                                       return cb(err,null);
+                               if (!!paper)
+                                       return cb(null,{paper:paper,questions:questions});
+                               AssessmentEntity.startSession(aid, number, password, (err2,ret) => {
+                                       const pwd = TokenGen.generate(12); //arbitrary number, 12 seems enough...
+                                       cb(err2, {
+                                               questions: questions,
+                                               password: pwd,
+                                       });
                                });
                        });
                });
        },
 
+       newAnswer: function(aid, number, password, input, cb)
+       {
+               console.log(JSON.stringify(input));
+               // Check that student hasn't already answered
+               AssessmentEntity.hasInput(aid, number, password, input.index, (err,ret) => {
+                       if (!!err)
+                               return cb(err,null);
+                       if (!!ret)
+                               return cb({errmsg:"Question already answered"},null);
+                       AssessmentEntity.setInput(aid, number, password, input, (err2,ret2) => {
+                               console.log(JSON.stringify(ret2));
+                               if (!!err2 || !ret2)
+                                       return cb(err2,ret2);
+                               return cb(null,ret2);
+                       });
+               });
+       },
+
        endSession: function(aid, number, password, cb)
        {
                AssessmentEntity.endAssessment(aid, number, password, (err,ret) => {
index c574f1f..5fe24cd 100644 (file)
@@ -11,7 +11,8 @@ function checkWindowSize()
        // NOTE: temporarily accept smartphone (security hole: pretend being a smartphone on desktop browser...)
        if (navigator.userAgent.match(/(iPhone|iPod|iPad|Android|BlackBerry)/))
                return true;
-       return window.innerWidth == screen.width && window.innerHeight == screen.height;
+       // 3 is arbitrary, but a small tolerance is required (e.g. in Firefox)
+       return window.innerWidth >= screen.width-3 && window.innerHeight >= screen.height-3;
 };
 
 new Vue({
@@ -27,15 +28,11 @@ new Vue({
                //       4: show answers
                stage: assessment.mode != "open" ? 0 : 1,
                remainingTime: 0, //global, in seconds
+               warnMsg: "",
        },
        components: {
                "statements": {
                        props: ['assessment','inputs','student','stage'],
-                       data: function() {
-                               return {
-                                       index: 0, //current question index in assessment.indices
-                               };
-                       },
                        // TODO: general render function for nested exercises
                        // TODO: with answer if stage==4 : class "wrong" if ticked AND stage==4 AND received answers
                        // class "right" if stage == 4 AND received answers (background-color: red / green)
@@ -43,7 +40,7 @@ new Vue({
                        // Full questions tree is rendered, but some parts hidden depending on display settings
                        render(h) {
                                let self = this;
-                               let questions = assessment.questions.map( (q,i) => {
+                               let questions = (assessment.questions || [ ]).map( (q,i) => {
                                        let questionContent = [ ];
                                        questionContent.push(
                                                h(
@@ -69,7 +66,7 @@ new Vue({
                                                                "input",
                                                                {
                                                                        domProps: {
-                                                                               checked: this.inputs[i][idx],
+                                                                               checked: this.inputs.length > 0 && this.inputs[i][idx],
                                                                        },
                                                                        attrs: {
                                                                                id: this.inputId(i,idx),
@@ -124,7 +121,7 @@ new Vue({
                                                {
                                                        "class": {
                                                                "question": true,
-                                                               "hide": this.stage == 2 && assessment.display == 'one' && assessment.indices[this.index] != i,
+                                                               "hide": this.stage == 2 && assessment.display == 'one' && assessment.indices[assessment.index] != i,
                                                        },
                                                },
                                                questionContent
@@ -132,7 +129,6 @@ new Vue({
                                });
                                if (this.stage == 2)
                                {
-                                       // TODO: one button per question
                                        questions.unshift(
                                                h(
                                                        "button",
@@ -148,7 +144,7 @@ new Vue({
                                                                        "margin-right": "auto",
                                                                },
                                                                on: {
-                                                                       click: () => this.sendAnswer(assessment.indices[this.index]),
+                                                                       click: () => this.sendAnswer(assessment.indices[assessment.index]),
                                                                },
                                                        },
                                                        "Send"
@@ -193,14 +189,16 @@ new Vue({
                                },
                                trySendCurrentAnswer: function() {
                                        if (this.stage == 2)
-                                               this.sendAnswer(assessment.indices[this.index]);
+                                               this.sendAnswer(assessment.indices[assessment.index]);
                                },
                                // stage 2
                                sendAnswer: function(realIndex) {
-                                       if (this.index == assessment.questions.length - 1)
+                                       console.log(realIndex);
+                                       if (assessment.index == assessment.questions.length - 1)
                                                this.$emit("gameover");
                                        else
-                                               this.index++;
+                                               assessment.index++;
+                                       this.$forceUpdate(); //TODO: shouldn't be required
                                        if (assessment.mode == "open")
                                                return; //only local
                                        let answerData = {
@@ -221,7 +219,7 @@ new Vue({
                                                dataType: "json",
                                                success: ret => {
                                                        if (!!ret.errmsg)
-                                                               return alert(ret.errmsg);
+                                                               return this.$emit("warning", ret.errmsg);
                                                        //socket.emit(message.newAnswer, answer);
                                                },
                                        });
@@ -236,7 +234,15 @@ new Vue({
                        return this.padWithZero(minutes) + ":" + this.padWithZero(seconds);
                },
        },
+       mounted: function() {
+               $(".modal").modal();
+       },
        methods: {
+               // In case of AJAX errors
+               warning: function(message) {
+                       this.warnMsg = message;
+                       $("#warning").modal("open");
+               },
                padWithZero: function(x) {
                        if (x < 10)
                                return "0" + x;
@@ -253,7 +259,7 @@ new Vue({
                                dataType: "json",
                                success: s => {
                                        if (!!s.errmsg)
-                                               return alert(s.errmsg);
+                                               return this.warning(s.errmsg);
                                        this.stage = 1;
                                        this.student = s.student;
                                        Vue.nextTick( () => { Materialize.updateTextFields(); });
@@ -268,11 +274,11 @@ new Vue({
                },
                // stage 1 --> 2 (get all questions, set password)
                startAssessment: function() {
-                       let initializeStage2 = questions => {
+                       let initializeStage2 = (questions,paper) => {
                                $("#leftButton, #rightButton").hide();
                                if (assessment.time > 0)
                                {
-                                       this.remainingTime = assessment.time * 60;
+                                       this.remainingTime = assessment.time * 60 - (!!paper ? paper.startTime/1000 : 0);
                                        this.runTimer();
                                }
                                // Initialize structured answer(s) based on questions type and nesting (TODO: more general)
@@ -280,9 +286,20 @@ new Vue({
                                        assessment.questions = questions;
                                for (let q of assessment.questions)
                                        this.inputs.push( _(q.options.length).times( _.constant(false) ) );
-                               assessment.indices = assessment.fixed
-                                       ? _.range(assessment.questions.length)
-                                       : _.shuffle( _.range(assessment.questions.length) );
+                               if (!paper)
+                               {
+                                       assessment.indices = assessment.fixed
+                                               ? _.range(assessment.questions.length)
+                                               : _.shuffle( _.range(assessment.questions.length) );
+                               }
+                               else
+                               {
+                                       // Resuming
+                                       let indices = paper.inputs.map( input => { return input.index; });
+                                       let remainingIndices = _.difference(_.range(assessment.questions.length), indices);
+                                       assessment.indices = indices.concat( _.shuffle(remainingIndices) );
+                               }
+                               assessment.index = !!paper ? paper.inputs.length : 0;
                                this.stage = 2;
                                Vue.nextTick( () => {
                                        // Run Prism + MathJax on questions text
@@ -294,8 +311,6 @@ new Vue({
                        };
                        if (assessment.mode == "open")
                                return initializeStage2();
-                       // TODO: if existing password cookie: get stored answers (papers[number cookie]), inject (inputs), set index+indices
-                       //       (instead of following ajax call)
                        $.ajax("/start/assessment", {
                                method: "GET",
                                data: {
@@ -305,18 +320,26 @@ new Vue({
                                dataType: "json",
                                success: s => {
                                        if (!!s.errmsg)
-                                               return alert(s.errmsg);
-                                       this.student.password = s.password;
-                                       // Got password: students answers locked to this page until potential teacher
-                                       // action (power failure, computer down, ...)
-                                       // TODO: set password cookie
+                                               return this.warning(s.errmsg);
+                                       if (!!s.paper)
+                                       {
+                                               // Resuming: receive stored answers + startTime
+                                               this.student.password = s.paper.password;
+                                               this.inputs = s.paper.inputs.map( inp => { return inp.input; });
+                                       }
+                                       else
+                                       {
+                                               this.student.password = s.password;
+                                               // Got password: students answers locked to this page until potential teacher
+                                               // action (power failure, computer down, ...)
+                                       }
                                        // TODO: password also exchanged by sockets to check identity
                                        //socket = io.connect("/" + assessment.name, {
                                        //      query: "number=" + this.student.number + "&password=" + this.password
                                        //});
                                        //socket.on(message.allAnswers, this.setAnswers);
                                        //socket.on("disconnect", () => { }); //TODO: notify monitor (highlight red), redirect
-                                       initializeStage2(s.questions);
+                                       initializeStage2(s.questions, s.paper);
                                },
                        });
                },
@@ -352,7 +375,7 @@ new Vue({
                                dataType: "json",
                                success: ret => {
                                        if (!!ret.errmsg)
-                                               return alert(ret.errmsg);
+                                               return this.warning(ret.errmsg);
                                        assessment.conclusion = ret.conclusion;
                                        this.stage = 3;
                                        delete this.student["password"]; //unable to send new answers now
index 559f08f..49410c4 100644 (file)
@@ -47,17 +47,21 @@ router.post("/update/assessment", access.ajax, access.logged, (req,res) => {
 router.get("/start/assessment", access.ajax, (req,res) => {
        let number = req.query["number"];
        let aid = req.query["aid"];
-       let error = validator({ _id:aid, papers:[{number:number}] }, "Assessment");
+       let password = req.cookies["password"]; //potentially from cookies, resuming
+       let error = validator({ _id:aid, papers:[{number:number,password:password || "samplePwd"}] }, "Assessment");
        if (error.length > 0)
                return res.json({errmsg:error});
-       AssessmentModel.startSession(ObjectId(aid), number, (err,ret) => {
+       AssessmentModel.startSession(ObjectId(aid), number, password, (err,ret) => {
                access.checkRequest(res,err,ret,"Failed session initialization", () => {
-                       // Set password
-                       res.cookie("password", ret.password, {
-                               httpOnly: true,
-                               maxAge: params.cookieExpire,
-                       });
-                       res.json(ret); //contains questions+password
+                       if (!password)
+                       {
+                               // Set password
+                               res.cookie("password", ret.password, {
+                                       httpOnly: true,
+                                       maxAge: params.cookieExpire,
+                               });
+                       }
+                       res.json(ret); //contains questions+password(or paper if resuming)
                });
        });
 });
@@ -70,7 +74,7 @@ router.get("/send/answer", access.ajax, (req,res) => {
        let error = validator({ _id:aid, papers:[{number:number,password:password,inputs:[input]}] }, "Assessment");
        if (error.length > 0)
                return res.json({errmsg:error});
-       AssessmentEntity.setInput(ObjectId(aid), number, password, input, (err,ret) => {
+       AssessmentModel.newAnswer(ObjectId(aid), number, password, input, (err,ret) => {
                access.checkRequest(res,err,ret,"Cannot send answer", () => {
                        res.json({});
                });
index b4ba8c8..c5395d6 100644 (file)
@@ -13,15 +13,10 @@ block content
        .container#assessment
                .row
                        #warning.modal
-                               .modal-content
-                                       p Your answer to the current question was sent to the server.
-                                       p To avoid future unpleasant surprises, please don't
-                                       ul
-                                               li resize the window, or
-                                               li lose window focus.
+                               .modal-content {{ warnMsg }}
                                .modal-footer
                                        .center-align
-                                               a.modal-action.modal-close.waves-effect.waves-light.btn-flat(href="#!") Got it!
+                                               a.modal-action.modal-close.waves-effect.waves-light.btn-flat(href="#!") Ok
                .row
                        .col.s12.m10.offset-m1.l8.offset-l2.xl6.offset-xl3
                                h4= assessment.name
@@ -52,7 +47,7 @@ block content
                                                .card
                                                        .timer.center(v-if="stage==2") {{ countdown }}
                                        .card
-                                               statements(:assessment="assessment" :student="student" :stage="stage" :inputs="inputs" @gameover="endAssessment")
+                                               statements(:assessment="assessment" :student="student" :stage="stage" :inputs="inputs" @gameover="endAssessment" @warning="warning")
                                #stage3(v-show="stage==3")
                                        .card
                                                .finish Exam completed &#9786; ...don't close the window!