how to insert multiple JSON objects to one property of a schema? - node.js

Question

I have a requirement to store multiple JSON objects in a property of schema.
take this example...
const Schema = require("mongoose").Schema;
const Student= Schema({
student_id: String,
name:String
attendance:[
{
date: Date,
Status: String
}
]
});
I need to insert attendance of individual student which looks like this..
student_id: student_001,
name:'Joe'
attendance:[
{
date: 24-10-2018,
status: 'Present'
},
{
date: 25-10-2018,
status: 'Absent'
},
//list goes on
]
I am using NodeJs as Backend, EJS template as front end and mongodb database. Date and Status comes when user submits data from front end. So I am having hard time writing my post request. Any types of comments / suggestions / change of model structure are welcome. Thank you.

Answer 1

You can create a separate attendance Schema.
const Schema = require("mongoose").Schema;
const AttendanceSchema = new Schema({
date: Date,
status: String
});
const StudentSchema = new Schema({
student_id: String,
name:String
attendance:[AttendanceSchema]
});
const Student = mongoose.model('Student', StudentSchema);
Add a new Student.
let newStudent = new Student({
student_id: student_001,
name:'Joe'
});
newStudent.save();
Update attendance:
let att1 = {
date: 24-10-2018,
status: 'Present'
};
// Here 'id' is id of particular student.
Student.update({ _id: id }, { $push: { attendance: att1 } })
.then(() => console.log("Success"))
.catch(err => console.log(err));
At some point later:
let att2 = {
date: 25-10-2018,
status: 'Absent'
};
// Here 'id' is id of particular student.
Student.update({ _id: id }, { $push: { attendance: att2 } })
.then(() => console.log("Success"))
.catch(err => console.log(err));

Answer 2

I suggest you to change the model structure to be normalized.
This will improve your experience in future statistics querying.
Also, one more suggestion - do not use string indentifiers in mongoDB, this can cause a headache in maintaining their uniqueness. Mongo has automated _id property assigning to each document, you could use it if you need to indentify any object.
Considering my suggestions - the code will look like:
const Schema = require("mongoose").Schema;
const Student = Schema({
name: String
});
const Attendance = Schema({
date: Date,
status: String,
student_id: {
type: Schema.Types.ObjectId,
ref: 'Student'
}
})
Then, you could simply create attendance records assigned to the student :
const attendance = new AttendanceModel({
date: new Date('05/20/2018'),
status: "present",
student_id: "somestudentid"
});