models/course.js

   1 const UserModel = require("../models/user");
   2 const AssessmentModel = require("../models/assessment");
   3 const db = require("../utils/database");
   4
   5 const CourseModel =
   6 {
   7     /*
   8      * Structure:
   9      *   _id: BSON id
  10      *   uid: prof ID
  11      *   code: varchar
  12      *   description: varchar
  13      *   password: monitoring password hash
  14      *   students: array of
  15      *     number: student number
  16      *     name: varchar
  17      *     group: integer
  18      */
  19
  20     //////////////////
  21     // BASIC FUNCTIONS
  22
  23     getByUser: function(uid, callback)
  24     {
  25         db.courses.find(
  26             { uid: uid },
  27             callback
  28         );
  29     },
  30
  31     getById: function(cid, callback)
  32     {
  33         db.courses.findOne(
  34             { _id: cid },
  35             callback
  36         );
  37     },
  38
  39     getByPath: function(uid, code, callback)
  40     {
  41         db.courses.findOne(
  42             {
  43                 $and: [
  44                     { uid: uid },
  45                     { code: code },
  46                 ]
  47             },
  48             callback
  49         );
  50     },
  51
  52     insert: function(uid, code, description, cb)
  53     {
  54         db.courses.insert(
  55             {
  56                 uid: uid,
  57                 code: code,
  58                 description: description,
  59                 students: [ ],
  60             },
  61             cb);
  62     },
  63
  64     setStudents: function(cid, students, cb)
  65     {
  66         db.courses.update(
  67             { _id: cid },
  68             { $set: { students: students } },
  69             cb
  70         );
  71     },
  72
  73     // Note: return { students: { ... } }, pointing on the requested row
  74     getStudent: function(cid, number, cb)
  75     {
  76         db.courses.findOne(
  77             { _id: cid },
  78             {
  79                 _id: 0,
  80                 students: { $elemMatch: {number: number} }
  81             },
  82             cb
  83         );
  84     },
  85
  86     setPassword: function(cid, pwd, cb)
  87     {
  88         db.courses.update(
  89             { _id: cid },
  90             { $set: { password: pwd } },
  91             cb
  92         );
  93     },
  94
  95     remove: function(cid, cb)
  96     {
  97         db.courses.remove(
  98             { _id: cid },
  99             cb
 100         );
 101     },
 102
 103     /////////////////////
 104     // ADVANCED FUNCTIONS
 105
 106     getByInitials: function(initials, callback)
 107     {
 108         UserModel.getByInitials(initials, (err,user) => {
 109             if (!!err || !user)
 110                 callback(err, []);
 111             else
 112             {
 113                 CourseModel.getByUser(user._id, (err2,courseArray) => {
 114                     callback(err2, courseArray);
 115                 });
 116             }
 117         });
 118     },
 119
 120     getByRefs: function(initials, code, callback)
 121     {
 122         UserModel.getByInitials(initials, (err,user) => {
 123             if (!!err || !user)
 124                 callback(err, []);
 125             else
 126             {
 127                 CourseModel.getByPath(user._id, code, (err2,course) => {
 128                     callback(err2, course);
 129                 });
 130             }
 131         });
 132     },
 133
 134     importStudents: function(uid, cid, students, cb)
 135     {
 136         // 1) check if uid == course uid
 137         CourseModel.getById(cid, (err,course) => {
 138             if (!!err || !course || !course.uid.equals(uid))
 139                 return cb({errmsg:"Not your course"},{});
 140             // 2) Set students
 141             CourseModel.setStudents(cid, students, cb);
 142         });
 143     },
 144
 145     setPassword: function(uid, cid, pwd, cb)
 146     {
 147         // 1) check if uid == course uid
 148         CourseModel.getById(cid, (err,course) => {
 149             if (!!err || !course || !course.uid.equals(uid))
 150                 return cb({errmsg:"Not your course"},{});
 151             // 2) Insert new student (overwrite if number already exists)
 152             CourseModel.setPassword(cid, pwd, cb);
 153         });
 154     },
 155
 156     remove: function(uid, cid, cb)
 157     {
 158         // 1) check if uid == course uid
 159         CourseModel.getById(cid, (err,course) => {
 160             if (!!err || !course || !course.uid.equals(uid))
 161                 return cb({errmsg:"Not your course"},{});
 162             // 2) remove all associated assessments
 163             AssessmentModel.removeGroup(cid, (err2,ret) => {
 164                 if (!!err)
 165                     return cb(err,{});
 166                 // 3) remove course (with its students)
 167                 CourseModel.remove(cid, cb);
 168             });
 169         });
 170     },
 171 }
 172
 173 module.exports = CourseModel;