MongoDB if field does not exist insert - javascript

i have category schema and i want to insert new category if category name does not exist. I tried something but i could not any response.
category.model
var mongoose = require("mongoose");
var categorySchema = mongoose.Schema({
name: {
type: String,
require: true
},
createdAt: {
type: Date,
default: () => {
return new Date();
}
}
});
module.exports = mongoose.model("category", categorySchema);
category insert function
var Category = require("../models/category.model");
exports.create = (req, res) => {
Category.find({ name: req.body.name }, (err, cat) => {
if (cat.length > 0) {
// i want to return exists message here
} else {
// i want to insert here if not exists
var category = new Category();
category.name = req.body.name;
category.save(err => {
if (err) {
return new response(null, err).error500(res);
}
return new response(category, null).created(res);
});
}
});
};

You can do it like this code below:
exports.create = async (req, res) => {
try {
let category = await Category.find({ name: req.body.name });
if(category) {
// return or do some stuff here
}
category = new Category(req.body);
category = await category.save();
return new response(category, null).created(res);
} catch(ex) {
console.log(ex.message);
return new response(null, ex).error500(res);
}
};
I hope it can help you.

Related

Why could the findOrCreate plugin create several documents at once?

I'm currently working on a MERN application with following/follower function for the users. I decided to create separate schemas for following and follower relationships detached from user schema.
Follower schema
const mongoose = require('mongoose');
const findOrCreate = require('mongoose-findorcreate');
const ObjectId = mongoose.Schema.Types.ObjectId;
const followerSchema = mongoose.Schema({
userId: {
type: ObjectId,
ref: 'User'
},
follower: {
type: [ObjectId],
ref: 'User'
}
});
followerSchema.plugin(findOrCreate);
const Follower = mongoose.model('Follower', followerSchema);
module.exports = { followerSchema, Follower };
Following schema
const mongoose = require('mongoose');
const findOrCreate = require('mongoose-findorcreate');
const ObjectId = mongoose.Schema.Types.ObjectId;
const followingSchema = mongoose.Schema({
userId: {
type: ObjectId,
ref: 'User'
},
following: {
type: [ObjectId],
ref: 'User'
}
});
followingSchema.plugin(findOrCreate);
const Following = mongoose.model('Following', followingSchema);
module.exports = { followingSchema, Following };
The problem however starts in my service where followings are created as supposed to. However, for followers mongoose create 6-8 documents at once with userIds that don't even exist in my db.
Here's the code of the followerService (it's the first function)
const { Follower } = require('../models/followerModel');
const { Following } = require('../models/followingModel');
const { User } = require('../models/userModel');
const mongoose = require('mongoose');
exports.changeFollowStatus = async (user, userId) => {
console.log({ userId: userId, user: user._id });
const newFollowing = await Following.findOrCreate({ userId: user._id }, (err, following, created) => {
console.log({following: following});
if (!err && !isFollowing(following, userId)) {
following.following.push(mongoose.Types.ObjectId(userId));
following.save();
User.findByIdAndUpdate(mongoose.Types.ObjectId(userId), {$inc: {follower: 1}});
} else {
const followingIndex = following.following.indexOf(mongoose.Types.ObjectId(userId));
following.following.splice(followingIndex, 1);
following.save();
User.findByIdAndUpdate(mongoose.Types.ObjectId(userId), { $inc: { follower: -1 } });
}
});
const newFollower = await Follower.findOrCreate({ userId: mongoose.Types.ObjectId(userId) }, (err, follower, created) => {
console.log({follower: follower});
if (!err && !isFollower(follower, user._id)) {
follower.follower.push(user._id);
follower.save();
User.findByIdAndUpdate(user._id, { $inc: { following: 1 } });
} else {
const followerIndex = follower.follower.indexOf(user._id);
follower.follower.splice(followerIndex, 1);
follower.save();
User.findByIdAndUpdate(user._id, { $inc: { following: -1 } });
}
});
};
exports.showFollowings = async (userId) => {
const followings = await Following.findOrCreate({ userId: mongoose.Types.ObjectId(userId) });
return followings.following;
};
exports.showFollowers = async (userId) => {
const followers = await Follower.findOrCreate({ userId: mongoose.Types.ObjectId(userId) });
return followers.follower;
};
const isFollowing = (newFollowing, userId) => {
return newFollowing.following.includes(mongoose.Types.ObjectId(userId));
};
const isFollower = (newFollower, userId) => {
return newFollower.follower.includes(userId);
}
Now, my following adding code and follower adding code look almost identical, but for some reason for followers, mongoose creates many more documents. The strange thing is that there is a follower document with the correct userId, but many other with random userIds get created which doesn't happen with followings which works as supposed to.
I also checked whether I pass the correct values and everything seems to be fine. But just for reference, here's the controller function from which I pass the values.
exports.changeFollowingStatus = async (req, res, next) => {
passport.authenticate('jwt', async (err, user, info) => {
if (err) {
console.error({ authError: err });
};
if (info !== undefined) {
console.error({ authError: info.message });
res.status(403).send(info.message);
} else {
console.log({params: req.params});
const userToFollow = req.params.id;
await FollowerService.changeFollowStatus(user, userToFollow);
res.status(200).send({ message: 'success' })
}
})(req, res, next);
};
Could anyone help me with this bug or at least navigate me towards the right direction? I can't seem to find solution to my problem. Thank you all in advance!

Cannot read property 'count' of undefined Express API

When i call Create Option api it is working fine but when i call list api get error: Cannot read property 'count' of undefined Express (Node + MongoDB) API.here is my Option Controller File code.
i have Log DB.ProductDoption ,getting result but count function not working.
const _ = require('lodash');
const Joi = require('joi');
exports.create = async (req, res, next) => {
try {
const validateSchema = Joi.object().keys({
name: Joi.string().required(),
key: Joi.string().required(),
description: Joi.string().allow(['', null]).optional(),
options: Joi.array().items(Joi.object().keys({
key: Joi.string().required(),
displayText: Joi.string().required()
})).required()
});
const validate = Joi.validate(req.body, validateSchema);
if (validate.error) {
return next(PopulateResponse.validationError(validate.error));
}
const key = Helper.String.createAlias(req.body.key);
console.log(DB.ProductDoption);
const count = await DB.ProductDoption.count({ key });
if (count || validate.value.key === '_custom') {
return next(PopulateResponse.error({
message: 'Please add unique name for key'
}));
}
const option = new DB.ProductDoption(validate.value);
await option.save();
res.locals.option = option;
return next();
} catch (e) {
return next(e);
}
};
exports.list = async (req, res, next) => {
const page = Math.max(0, req.query.page - 1) || 0; // using a zero-based page index for use with skip()
const take = parseInt(req.query.take, 10) || 10;
try {
const query = Helper.App.populateDbQuery(req.query, {
text: ['name', 'key', 'description']
});
const sort = Helper.App.populateDBSort(req.query);
const count = await DB.ProductDoption.count(query);
const items = await DB.ProductDoption.find(query)
.collation({ locale: 'en' })
.sort(sort).skip(page * take)
.limit(take)
.exec();
res.locals.optionList = {
count,
items
};
next();
} catch (e) {
next(e);
}
};
collection.count is deprecated, and will be removed in a future version. Use Collection.countDocuments or Collection.estimatedDocumentCount instead

Why is this mongoose 'findOne' query always returning null?

I am trying to find a specific document with mongoose in my Cosmosdb with this query described below.
const mongoose = require('mongoose');
var ObjectID = require('mongodb').ObjectID
const keys = require('../config/keys');
const Item = mongoose.model('items');
const uploadToBlob = async (containerName, blobName, json, id) => {
console.log('id', id)
Item.findOne({ _id: id }, (foundItem) => {
console.log(foundItem)
});
console.log('here')
Item.findOneAndDelete({ name: blobName });
};
I am successfully able to find the document when querying like this below.
const scanMongo = () => {
Item.find({
_id: {
$gt: ObjectID.createFromTime(Date.now() / keys.mongoPurgeInterval)
}}, (err, foundItems) => {
if(err) {
console.log("Oops", err);
return;
}
foundItems.forEach(item => {
JSON.stringify(item)
const blobName = item.name;
json = "'"+item+"'"
const id = item._id
uploadToBlob(keys.containerName, blobName, json, id);
});
});
}
This is what the object I'm looking for looks like when pulled from the query above.
[ { _id: 5cabd5c6e16288230cba2cf6, name: 'test', value: 1, __v: 0 } ]
For kicks, here my model.
const mongoose = require('mongoose');
const { Schema } = mongoose;
const itemSchema = new Schema({
name: String,
value: Number,
});
mongoose.model('items', itemSchema);
I'm befuddled. Any help would be bawler. Thanks!!!
Yeah, the first parameter is supposed to catch the error.
Item.findOne({ _id: id }, (error, foundItem) => {
console.log(foundItem)

Update fields in object with mongoose in mongodb

I have a simple collection in mongodb.
I use mongoose.
I have users model with one field type object.
And I want change this object dynamically. But this code doesn't work, I used findByIdAndUpdate(), findById, findOne(), findOneAndUpdate().
const UsersSchema = mongoose.Schema({
likes: {}
},
{ collection: 'users' });
const Users = mongoose.model('Users', UsersSchema);
const id ="5b4c540f14f353a4b9875af4";
const thems = ['foo', 'bar'];
Users.findById(id, (err, res) => {
thems.map(item => {
if (res.like[item]) {
res.like[item] = res.like[item] + 1;
} else {
res.like[item] = 1;
}
});
res.save();
});
I believe that, for solve this problem you need to add more fields in your schema:
I created one example with this data:
const UsersSchema = new mongoose.Schema({
likes :[
{
thema:{
type: String
},
likes_amount:{
type: Number
},
_id:false
}]
});
module.exports = mongoose.model('Users', UsersSchema);
I added one user:
var newUser = new UserModel({
likes:[{
thema:'foo',
likes_amount:1
}]
});
newUser.save();
Here the code that increment the likes per thema:
const thems = ['foo', 'bar'];
const userId = "5b4d0b1a1ce6ac3153850b6a";
UserModel.findOne({_id:userId})
.then((result) => {
var userThemas = result.likes.map(item => {
return item.thema;
});
for (var i = 0; i < thems.length; i++) {
//if exists it will increment 1 like
if (userThemas.includes(thems[i])) {
UserModel.update({_id: result._id, "likes.thema" : thems[i]}, {$inc: {"likes.$.likes_amount": 1}})
.then((result) => {
console.log(result);
}).catch((err) => {
console.log(err)
});
} else {
//if doesn't exist it will create a thema with 1 like
UserModel.update({_id: result._id},
{
$addToSet: {
likes: {
$each: [{thema: thems[i], likes_amount: 1}]
}
}})
.then((result) => {
console.log(result);
}).catch((err) => {
console.log(err)
});
}
}
}).catch((err) => {
console.log(err)
});
Database result of this increment:
I hope that it can help you.

Return data from two models

Hello, guys. Please help me. How I can get 'topics' array and append it to res.view(). I tried many variants. But always in 'topics' I got 'undefind'.
Subjects.query("SELECT `subjects`.`id`, `subjects`.`name` AS `subject` FROM `subjects`
WHERE `subjects`.`faculty` = " + faculty_id, function (err, subs)
{
subs.forEach(function(subject, topics)
{
var topics = new Array();
Topics.query("SELECT `topics`.`id`, `topics`.`name` AS `topic` FROM `topics`
WHERE `topics`.`subject` = " + subject.id, function (err, tops)
{
topics[subject.id] = tops;
});
console.log(topics);
});
res.view({
title: 'Private cabinet',
users: user[0],
subjects: subs,
});
});
I tried many variants, but only this works:
var async = require('async');
_ = require('lodash');
module.exports = {
'cabinet': function (req, res)
{
async.auto(
{
user: function(cb)
{
User.query("SELECT `users`.`email`, `users`.`id`, `users`.`name`, `users`.`surname`, `users`.`lastname`, `groups`.`name` as `group`, `faculties`.`name` as `faculty`, `faculties`.`id` AS `faculty_id` FROM `users`, `groups`, `faculties` WHERE `users`.`id` = " + req.session.user + " AND `users`.`group` = `groups`.`id` AND `faculties`.`id` = `groups`.`faculty` GROUP BY `users`.`id`", cb);
},
subjects: ['user', function(cb, async_data)
{
var faculty = async_data.user.map(function (item){return item.faculty_id});
Subjects.find()
.where({faculty: faculty})
.exec(cb);
}],
topics: ['subjects', function(cb, async_data)
{
var subject = async_data.subjects.map(function (item){return item.id});
Topics.find()
.where({subject: subject})
.exec(cb);
}]
},
function allDone (err, async_data)
{
if (err) return res.serverError(err);
var user = async_data.user;
var subjects = async_data.subjects;
var topics = async_data.topics;
_.map(user, function (user) {
var theseSubjects =
_.where(subjects, {faculty: user.faculty_id });
subjects = theseSubjects;
_.map(subjects, function (subject) {
var theseTopics =
_.where(topics, {subject: subject.id });
subject.topics = theseTopics;
});
});
res.view({
title: 'Личный кабинет',
user: user[0],
subjects: subjects
});
});
},

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