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How to save an array of strings in mongodb

I have found a few similar questions on stack overflow like this one:
How to save array of Strings in Node Mongodb
Mongoose - Save array of strings
but I cant figure out why my method is not working
I am trying to save the string of arrays "jobType".
context: I am creating an app where people can post jobs.
each job can have multiple types.
here is my job model::
const mongoose = require("mongoose");
const postSchema = mongoose.Schema({
content: { type: String, required: true },
imagePath: { type: String, required: true },
state: { type: String, required: true },
substate: { type: String, required: true },
address: { type: String, required: true },
jobType: { type: [String] },
creator: { type: mongoose.Schema.Types.ObjectId, ref: "User", required: true }
});
module.exports = mongoose.model("Job", postSchema);
this is the API used to save the data on MongoDB:
I am 100% sure that the data is getting to the API correctly.
the parameter "req.body.jobtype" contains all the info as a string.
I am trying to use JSON.parse to change the string into an array but its not working.
when I check MongoDB, an empty array is being stored
const Job = require("../models/job");
exports.createJob = (req, res, next) => {
console.log('create job api hit')
const url = req.protocol + "://" + req.get("host");
const post = new Job({
content: req.body.content,
imagePath: url + "/images/" + req.file.filename,
creator: req.userData.userId,
state: 'new',
substate: 'new',
address: req.body.address,
jobtype: JSON.parse(req.body.jobtype) // fix: not storing correctly
});
post
.save()
.then(createdJob => {
res.status(201).json({
message: "Job added successfully",
post: {
...createdJob,
'pecker':'pecker hecks out',
id: createdJob._id
}
});
})
.catch(error => {
res.status(500).json({
message: JSON.stringify(error)
});
});
};

You have a typo. In your model, you defined jobType property, but when saving the data, you are passing it as jobtype.
So, instead of this:
jobtype: JSON.parse(req.body.jobtype)
Do this:
jobType: JSON.parse(req.body.jobtype)

How to create a foreign key in MongoDB with Mongoose?

I've a simple "table" user, where each user has a username, an email and a password. Into users.js:
const mongoose = require('mongoose')
const UserSchema = new mongoose.Schema(
{
username: { type: String, required: true, unique: true },
email: { type: String, required: true, unique: true },
password: { type: String, required: true }
},
{ collection: 'users' }
)
const model = mongoose.model('UserSchema', UserSchema)
module.exports = model
Now, I want to define an account. One user can have one or more bank account. For example, I can have account_1 with a balance of 100$, account_2 with a balance of 200$ and so on. The problem is that the collection accounts, has two parameters: one is the user (and this is a foreign key, because it's the user nickname in the collection users), and the other one is the balance (a simple number). Into accounts.js:
const mongoose = require('mongoose')
const AccountSchema = new mongoose.Schema(
{
username: { type: String, required: true, unique: true },
balance: { type: Number, required: true},
},
{ collection: 'accounts' }
)
const model = mongoose.model('AccountSchema', AccountSchema)
module.exports = model
How can I say that the username into AccountSchema is the field of UserSchema?

You use refs in mongoose.
const mongoose = require('mongoose')
const Schema = mongoose.Schema
const AccountSchema = new mongoose.Schema(
{
username: { type: Schema.Types.ObjectId, required: true, ref: "user },
balance: { type: Number, required: true},
},
{ collection: 'accounts' }
)
const model = mongoose.model('AccountSchema', AccountSchema)
Note: The ref should be the name you passed as the first parameter to the mongoose.model function in your users model.

Mongoose populating

i am a quite new to mongoose and mongodb and have been trying to connect my user with a bunch of image posts. I read a lot about mongoose populate but i keep on getting empty images [].
const mongoose = require('mongoose');
const userSchema = new mongoose.Schema({
email: {
type: String,
required: true
},
username: {
type: String,
required: true
},
password: {
type: String,
required: true
},
images: [
{
type: mongoose.Schema.Types.ObjectId,
ref: 'Image'
}
]
});
module.exports = mongoose.model('User', userSchema);
const mongoose = require('mongoose');
const imageSchema = new mongoose.Schema({
id: mongoose.Schema.Types.ObjectId,
image: {
type: String,
required: true
},
description: {
type: String,
required: true
},
})
module.exports = mongoose.model('Image', imageSchema);
const getOne = async (userId) => {
let lastTenImages = await User.findById(userId).populate('images').lean();
console.log(lastTenImages.images);
// return lastTenImages
}
I also used mongoose.Types.ObjectId instead of Schema but still got the same result- an empty array

In my opinion you should discard the id portion which is not working as the link to the User model. In other words try something like:
const imageSchema = new mongoose.Schema({
image: {
type: String,
required: true
},
description: {
type: String,
required: true
},
})
I think that should populate the right array.
In addition, when you get the value you will be getting an array of objects. So you would need to map over it. lastTenImages.images won't produce anything.

How to save document based on user id using mongoose?

I am trying to save template based on user id , How can i make sure when template save it save with user id _id ? i added reference to the templateSchema for User.
user.model.js
var UserSchema = new mongoose.Schema({
_id: { type: String, required: true, index: {unique: true}},
firstName: String,
lastName: String,
type: String,
groups:[{type: String, ref: 'Group', required: false}]
},
{
toObject: {
virtuals: true
},
toJSON: {
virtuals: true
}
});
export default mongoose.model('User', UserSchema);
template.model.js
var User = require('../user/user.model.js');
var TemplateSchema = new mongoose.Schema({
_id: { type: String, required: true},
name: String,
id: String,
appliesTo: [],
properties: [],
createdBy: { type: mongoose.Schema.Types.ObjectId, ref: 'User'}
});
export default mongoose.model('Templates', TemplateSchema);
template.controller.js
var eTemplate = require('./template.model');
export function create(req, res) {
console.log(req.body);
eTemplate.createAsync(req.body)
.then(responseWithResult(res, 201))
.catch(handleError(res));
}

Mongoose has two built-in functions that are called before (pre) and after (post) you save a document. My advice is to make use of them. Here is an example of my code in which I search for an sequence number before saving the user document. You can do the same: When you save the template, make a request for the user id to the database (Or vice-versa). You can even save one, get the id and save the other.
Bellow follows my code for the sequence and the user.
var UserSchema = new Schema({
username: { type: String, required: true, unique: true },
id: { type: String },
...
});
UserSchema.pre('save', function(next) {
let doc = this;
let id = 'userSeq'
Sequence.findByIdAndUpdate(id, { $inc : {nextSId : 1} }, function(error,data) {
if(error)
next(error)
doc.id = data.nextSId-1;
next();
})
});
I hope my answer was useful for you. Just a remark, pre and post are not called in the event of updates for the document.

Mongoose: Cast to ObjectId failed for value

I'm trying to specify the schema of my db in mongoose. At the moment I do this:
var Schema = mongoose.Schema;
var today = new Date(2011, 11, 12, 0, 0, 0, 0);
var personSchema = new Schema({
_id : Number,
name: { type: String, required: true },
tel: { type: String, required: true },
email: { type: String, required: true },
newsitems: [{ type: Schema.Types.ObjectId, ref:'NewsItem'}]
});
var taskSchema = new Schema({
_id: Number,
description: { type: String, required: true },
startDate: { type: Date, required: true },
newsitems: [{ type: Schema.Types.ObjectId, ref:'NewsItem'}]
});
var newsSchema = new Schema({
_id: Number,
creator : { type: Schema.Types.ObjectId, ref: 'Person' },
task : { type: Schema.Types.ObjectId, ref: 'Task' },
date: { type: Date, required:true },
loc: {type: String, required: true }
});
var NewsItem = mongoose.model('NewsItem', newsSchema);
var Person = mongoose.model('Person', personSchema);
var Task = mongoose.model('Task', taskSchema);
var tony = new Person({_id:0, name: "Tony Stark", tel:"234234234", email:"tony#starkindustries.com" });
var firstTask = new Task({_id:0, description:"Get an interview with the president", startDate:today});
var newsItem1 = new NewsItem({_id:0, creator: tony.id, task: firstTask.id, date: today, loc: "NY"});
newsItem1.save(function (err) {
if (err) console.log(err);
firstTask.save(function (err) {
if (err) console.log(err);
});
tony.save(function (err) {
if (err) console.log(err);
});
});
NewsItem
.findOne({ loc: "NY" })
.populate('creator')
.populate('task')
.exec(function (err, newsitem) {
if (err) console.log(err)
console.log('The creator is %s', newsitem.creator.name);
})
I create the schemas and try to save some data.
The error:
{ message: 'Cast to ObjectId failed for value "0" at path "creator"',
name: 'CastError',
type: 'ObjectId',
value: '0',
path: 'creator' }
I wrote this code based on : http://mongoosejs.com/docs/populate.html#gsc.tab=0
The db I try to create looks like this: Specify schema in mongoose .
How can I fix this?

The example from the mongoose docs you referenced uses Number for the personSchema._id field, and ObjectId for the others.
I presume they do this in the example only to demonstrate that it's possible to use either. If you do not specify _id in the schema, ObjectId will be the default.
Here, all your records have an _id field which is an ObjectId, yet you're treating them like numbers. Furthermore, fields like personID and taskID do not exist, unless you've left out the part where you define them.
If you did want to use numbers for all your _id fields, you'd have to define that in the schemas.
var newsSchema = new Schema({
_id: Number,
_creator: {type: ObjectId, ref: "Person"},
// ...
})
var personSchema = new Schema({
_id: Number,
// ...
})
Then to create a news item with a particular ID, and assign it to a creator:
var tony = new Person({_id: 0});
var newsItem = new NewsItem({_id: 0, creator: tony.id});
However the thing to note here is that when you use something other than ObjectId as the _id field, you're taking on the responsibility of managing these values yourself. ObjectIds are autogenerated and require no extra management.
Edit: I also noticed that you're storing refs on both sides of your associations. This is totally valid and you may want to do it sometimes, but note that you'd have to take care of storing the references yourself in the pre hook.

I was receiving this error after creating a schema:
CastError: Cast to ObjectId failed for value “[object Object]” at path “_id”
Then modifying it and couldn't track it down. I deleted all the documents in the collection and I could add 1 object but not a second. I ended up deleting the collection in Mongo and that worked as Mongoose recreated the collection.