I have a notification model with this Schema here:
const NotificationSchema = new Schema({
type: {
type: String,
required: true
},
createdAt: {
type: Number,
required: true
},
postId: {
type: Schema.Types.ObjectId,
ref: 'post',
required: true
},
recipients: [{
type: Schema.Types.ObjectId,
ref: 'user',
required: true
}]
});
I'm building a route controller that will get all notifications where they are one of the recipients here:
getNotifications(req, res, next) {
const userId = req.params.id;
Notification.find({ recipients: userId })
.sort({ createdAt: 1 })
.then(notifications => res.send(notifications))
.catch(next);
},
I also want to make sure that if there are several notifications that have the same type, such as postAuthorNotification AND the same postId, then it only brings back the notification that has the latest createdAt timestamp.
The reason for this is that if a users' post gets commented on 20 times. There will be a notification for each. I only want to send the user back ONE notification though, the latest one.
Is this possible at all with mongo/mongoose?
Thank you.
You already have the .sort() method chained, which should give you results sorted by createdAt. To limit to only 1 result, simply chain a .limit(1) to the query.
Official documentation for the limit method - http://mongoosejs.com/docs/api.html#query_Query-limit
Related
I am trying to update the like count of job posts in my application using the $inc operator and the findByIdAndUpdate method from Mongoose. The correct document is being retrieved and returned but the like count for the job post never moves up from 0 and no updates are performed in the database collection.
Below is the code I am currently using to perform the update.
Jobs.findByIdAndUpdate(req.params._id , { $inc: {likes: 1}} , {new: true})
.then((ret) => {
res.send(ret)
})
Job schema
const mongoose = require('mongoose');
let JobSchema = mongoose.Schema({
student_name: {
type: String,
required: true
},
subject: {
type: String,
required: true
},
grade: {
type: Number,
required: true
},
area: {
type: String,
required: true
},
desc: {
type: String,
required: true
},
accepted: {
type: Boolean,
required: true,
default: false
},
tutor_name: {
type: String,
required: false
},
} , {collection: 'jobs'});
let Job = mongoose.model('Job' , JobSchema);
module.exports = Job;
Any insight into what is preventing the update from performing would be greatly appreciated
I have tried using two queries, one to retrieve the current likes of a post and another to manually update the doc with the incremented value. I have tried nesting the queries using .then() statements and have also tried the updateOne() and findOneAndUpdate() methods as alternatives. I have tried experimenting with the $set and $inc operators in my queries to see if either of them perform the changes, but neither do.
I am expecting the incremented 'likes' value to be reflected in the database and for the updated job document to be returned and echoed back to the console.
Your schema is missing a likes field, which means Mongoose will remove it from queries/updates (since it doesn't match the schema). Make sure to add it:
likes: {
type: Number,
default: 0
}
Can you try something like this (adding [] around update):
Jobs.findByIdAndUpdate(req.params._id , [{ $inc: {likes: 1}}] , {new: true})
.then((ret) => {
res.send(ret)
})
EDITED:
Jobs.findByIdAndUpdate(req.params._id , [{ $set: {likes: "$likes"+1}}] , {new: true})
.then((ret) => {
res.send(ret)
})
I am building a social media and one of the features I have is the ability to follow other users and have their posts show up on a home page, much like an Instagram feed. I have an endpoint that loops through all the users you are following and gets the post that are rated for your age, sorts them and puts them in an array.
router.get("/following", auth, async (req, res) => {
try {
const user = await User.findOne({ firebaseUID: req.authId });
const dob = dayjs(user.dob.toISOString().split("T")[0]);
const currentDate = dayjs(new Date().toISOString().split("T")[0]);
const age1 = currentDate.diff(dob, "year");
let posts = [];
for (let i = 0; i < user.following.length; i++) {
posts.push(
await Post.find({
userID: user.following[i].user,
age: { $lte: age1 },
})
);
}
posts = [].concat.apply([], posts);
posts = _.sortBy(posts, "date").reverse();
res.json(posts);
} catch (err) {
console.error(err.message);
res.status(500).json({ msg: "Server Error" });
}
});
The user schema looks like this
const UserSchema = new Schema({
firebaseUID: {
type: String,
required: true,
},
name: {
type: String,
required: true,
},
username: {
type: String,
required: true,
unique: true,
},
avatar: {
type: String,
},
dob: {
type: Date,
default: Date.now,
required: true,
},
slug: {
type: String,
},
following: [
//array of user IDs
{
user: {
type: Schema.Types.ObjectId,
ref: "users", //here so we know which lieks came from which users
},
},
],
followers: [
//array of user IDs
{
user: {
type: Schema.Types.ObjectId,
ref: "user", //here so we know which lieks came from which users
},
},
],
});
The problem is that I am trying to add infinite scroll pagination to the front end that will start by getting the first 15 posts and then get the next 15 and so on from endpoints that provide this.
What would the best way to do this be? For other routes, I have used .skip() and .limit(). I could split the array of posts up right before I send it as a response, but is there a way to do without getting all the posts as this would be taxing if you're following 100s of people with 1000s of posts.
I would need to loop through all the users you are following and get all their posts in line with your age rating but only get the first 15 sorted in date order from newest to oldest. Is there a mongoose function that I could use or would the best way be to split the array of posts?
Thank you.
I have a schema "Reports" that looks like this:
var Reports = new Schema(
{
identifiersub: { // Id of reported submission, populate stuff
type: Schema.Types.ObjectId,
ref: "Submission"
},
identifiercom: { // Id of reported comment, populate stuff
type: Schema.Types.ObjectId,
ref: "Comments"
},
identifieruse: { // Id of reported user, populate stuff
type: Schema.Types.ObjectId,
ref: "AccountDetails"
},
solved: { // Whether this problem has been solved or not
type: Boolean,
default: false
},
processed: [{ // Array of moderators who were participating in processing this report
type: Schema.Types.ObjectId,
ref: "AccountDetails"
}],
type: String, // Type of content. bug, user, submission or comment
reports: [ // Additional text for each type of reported content
{
description: String, // Text from select component. For bugs: the feature that is affected,
reason: String, // Reason for this report
by: { // Reporter
type: Schema.Types.ObjectId,
ref: "AccountDetails"
}
}
],
notes: [{ // Admin notes
title: String, // Fleshed out discussion/reasoning
note: String, // Decided outcome that each note represents
outcome: String, // ("Keep reported", "delete", etc)
date: Date, // Date this note was added
moderator: { // Moderator who added this note
type: Schema.Types.ObjectId,
ref: "AccountDetails"
}
}]
},
{ strict: false, timestamps: true }
)
And in my admin panel I want to implement a search function that searches all reports with the specified keyword. The most important field here is reports: it's an array of objects containing a "by" field which is an ObjectId. Now I wanted to populate the username for this id, but I'm not seeing it in my document...I use the .stream method to check the whole document including nested objects and arrays of objects. Here's my query:
var cursor = Reports
.find({ type: req.query.type})
.limit(500)
.populate("notes.moderator reports.by processed", "username")
.populate("identifieruse", "username dob email ipaddress")
.populate("identifiercom", "by.username comment")
.populate("identifiersub", "meta.title by deleted")
.sort("-createdAt")
.lean()
.stream();
cursor.on('data', function(doc) {
console.log(doc);
if (doc.toString().includes(key)) results.push(doc)
})
cursor.on('error', function(err) {
return catcherror(new Error(err), res)
})
cursor.on('close', function() {
console.log(results);
return res.send(results)
})
Thanks for help!
Use .cursor() instead of .stream() and it works.
I want to push an nested element Mongoose.
Check the schema:
const Messages = new mongoose.Schema({
/*[user]*/
author: {
type: Schema.Types.ObjectId,
ref: 'Users'
},
/*[room]*/
room: {
type: Schema.Types.ObjectId,
ref: 'Rooms'
},
message_body: String,
message_status:{type: Boolean, default: false},
created_at: { type: Date, default: Date.now }
});
I want to create a Message with room and Author insert, how to use that?
Imagine you have an 'author' object and a 'room' object. These are going to be the parents. Your message object would be like this:
var newMessage = new Message({author: authore._id, room: room._id, message_body: messageBody ....});
newMessage.save()
.then(() => {
/*** do more things **/
});
Then you will be able to use 'populate' option to make Mongoose refilling author and room fields with the whole objects.
I'm learning to use Node.js + Express to build a REST API. In this API
I have the following method:
apiRouter.route('/training/session/byId/:id_session')
// ===== GET =======
.get(function(req, res) {
//Get the session
Session.findById(req.params.id_session, function(err, session) {
//Get an array of exercise associated with the session
Exercise.find({session: session._id}, function(err, exercise) {
let movements = [];
let sets = [];
let i = exercise.length-1;
//For every exercise get the movements and the sets
exercise.forEach(function (ex,index) {
Movement.findById(ex.movement,function(err,movement){
if(movement)
movements.push(movement);
//***** Here?
Set.find({exercise: ex}, function (err, set) {
if(set.length)
sets.push(set);
if(index == i){
res.json({ message: 'ok' ,session,exercise,movements,sets});
}
})
})
})
});
});
})
The idea is obtain all the session related information from the database.
First:
I think that is not the correct way of make multiple querys and return an object with the info of all the querys, but I'm novice with the async working of Node... So what is the correct way to make multiple querys where the data of one query depends of other query?
Second: In the Front-End (React + Redux) I'm making Ajax request with axios and for the same Ajax request sometimes not all 'sets' are fetched (//***** Here?). The problem is in the API?
Thanks in advance.
EDIT: DB models
Session:
var SessionSchema = new Schema({
date: {type: Date, default: Date.now },
time: Number, //Time in seconds
user: {required: true, type: mongoose.Schema.Types.ObjectId, ref: 'User'},
});
Exercise:
var ExerciseSchema = new Schema({
session: {type: mongoose.Schema.Types.ObjectId, ref: 'Session'},
movement: {type: mongoose.Schema.Types.ObjectId, ref: 'Movement'},
timestamp: {
type: Date,
default: Date.now
}
});
Set:
var SetSchema = new Schema({
repetitions: Number,
weight: Number,
rest: Number,
timestamp: {
type: Date,
default: Date.now
},
exercise : {type: mongoose.Schema.Types.ObjectId, ref: 'Exercise'}
});
Movement:
var MovementSchema = new Schema({
name: { type: String, required: true, index: true, unique: true },
material:{ type: String, required: true},
muscles : [{
name : { type: String, required: true},
percentage : { type: Number, required: true}
}]
});
Set.find({exercise: ex}, function (err, set) {
if(set.length)
sets.push(set);
}).then(function(set){
if(index == i){
res.json({ message: 'ok' ,session,exercise,movements,sets});
}
})
Of course my prev answer wouldn't work. The set query callback would execute after the if(index == i). Actually I'm not sure this will produce different results from your code. I've never actually used Mongoose but as far as I know, you can't do joins so nested queries is the way to do it.
You might want to consider using promises. Not necessary, but they make your code easier to read and think about: http://eddywashere.com/blog/switching-out-callbacks-with-promises-in-mongoose/
It might make more sense as well to create a single result object that you build up as the queries return so you end up sending a single JSON object representing your session that looks like:
{
exercises: [
{
sets: [],
movements: [],
},
{
sets: [],
movements: [],
},
...
]
}