models/course.js

   1 const UserModel = require("../models/user");
   2 const db = require("../utils/database");
   3
   4 const CourseModel =
   5 {
   6     /*
   7      * Structure:
   8      *   _id: BSON id
   9      *   uid: prof ID
  10      *   code: varchar
  11      *   description: varchar
  12      *   password: monitoring password hash
  13      *   students: array of
  14      *     number: student number
  15      *     name: varchar
  16      *     group: integer
  17      */
  18
  19     //////////////////
  20     // BASIC FUNCTIONS
  21
  22     getByUser: function(uid, callback)
  23     {
  24         db.courses.find(
  25             { uid: uid },
  26             callback
  27         );
  28     },
  29
  30     getById: function(cid, callback)
  31     {
  32         db.courses.findOne(
  33             { _id: cid },
  34             callback
  35         );
  36     },
  37
  38     getByPath: function(uid, code, callback)
  39     {
  40         db.courses.findOne(
  41             {
  42                 $and: [
  43                     { uid: uid },
  44                     { code: code },
  45                 ]
  46             },
  47             callback
  48         );
  49     },
  50
  51     insert: function(uid, code, description, cb)
  52     {
  53         db.courses.insert(
  54             {
  55                 uid: uid,
  56                 code: code,
  57                 description: description,
  58                 students: [ ],
  59             },
  60             cb);
  61     },
  62
  63     setStudents: function(cid, students, cb)
  64     {
  65         db.courses.update(
  66             { _id: cid },
  67             { $set: { students: students } },
  68             cb
  69         );
  70     },
  71
  72     // Note: return { students: { ... } }, pointing on the requested row
  73     getStudent: function(cid, number, cb)
  74     {
  75         db.courses.findOne(
  76             { _id: cid },
  77             {
  78                 _id: 0,
  79                 students: { $elemMatch: {number: number} }
  80             },
  81             cb
  82         );
  83     },
  84
  85     setPassword: function(cid, pwd, cb)
  86     {
  87         db.courses.update(
  88             { _id: cid },
  89             { $set: { password: pwd } },
  90             cb
  91         );
  92     },
  93
  94     remove: function(cid, cb)
  95     {
  96         db.courses.remove(
  97             { _id: cid },
  98             cb
  99         );
 100     },
 101
 102     /////////////////////
 103     // ADVANCED FUNCTIONS
 104
 105     getByInitials: function(initials, callback)
 106     {
 107         UserModel.getByInitials(initials, (err,user) => {
 108             if (!!err || !user)
 109                 callback(err, []);
 110             else
 111             {
 112                 CourseModel.getByUser(user._id, (err2,courseArray) => {
 113                     callback(err2, courseArray);
 114                 });
 115             }
 116         });
 117     },
 118
 119     getByRefs: function(initials, code, callback)
 120     {
 121         UserModel.getByInitials(initials, (err,user) => {
 122             if (!!err || !user)
 123                 callback(err, []);
 124             else
 125             {
 126                 CourseModel.getByPath(user._id, code, (err2,course) => {
 127                     callback(err2, course);
 128                 });
 129             }
 130         });
 131     },
 132
 133     importStudents: function(uid, cid, students, cb)
 134     {
 135         // 1) check if uid == course uid
 136         CourseModel.getById(cid, (err,course) => {
 137             if (!!err || !course || !course.uid.equals(uid))
 138                 return cb({errmsg:"Not your course"},{});
 139             // 2) Set students
 140             CourseModel.setStudents(cid, students, cb);
 141         });
 142     },
 143
 144     setPassword: function(uid, cid, pwd, cb)
 145     {
 146         // 1) check if uid == course uid
 147         CourseModel.getById(cid, (err,course) => {
 148             if (!!err || !course || !course.uid.equals(uid))
 149                 return cb({errmsg:"Not your course"},{});
 150             // 2) Insert new student (overwrite if number already exists)
 151             CourseModel.setPassword(cid, pwd, cb);
 152         });
 153     },
 154
 155     remove: function(uid, cid, cb)
 156     {
 157         // 1) check if uid == course uid
 158         CourseModel.getById(cid, (err,course) => {
 159             if (!!err || !course || !course.uid.equals(uid))
 160                 return cb({errmsg:"Not your course"},{});
 161             // 2) remove all associated evaluations
 162             db.evaluations.remove(
 163                 { cid: cid },
 164                 (err2,ret) => {
 165                     if (!!err)
 166                         return cb(err,{});
 167                     // 3) remove course (with its students)
 168                     CourseModel.remove(cid, cb);
 169                 }
 170             );
 171         });
 172     },
 173 }
 174
 175 module.exports = CourseModel;