I am building a chat app using nodejs and mongoose. I need to retrieve chats for a user(logged in user) such that the retrieved data/chats will contain the latest message and the name of the user the logged in user had a chat with. I am not able to come app with a way to aggregate the data since the sender can also be a recipient in a chat. My message schema is shown below.
const messageSchema = new mongoose.Schema(
{
content: { type: String, required: true },
fromUser: { type: mongoose.Schema.Types.ObjectId, ref: "User" },
toUser: { type: mongoose.Schema.Types.ObjectId, ref: "User" },
users: Array,
messageRead: { type: Boolean, default: false },
},
{
timestamps: true,
}
);
The purpose of this is to have a list of chats render on the front end which when clicked will open an inbox containing messages between the two users.
You can just use the $or operator. This way it will return all elements where the user is the sender or recipient:
.aggregate([
{
$match: {
$or: [
{
fromUser: ObjectId("<UserID>")
},
{
toUser: ObjectId("<UserID>")
}
]
}
},
{ $sort: { createdDate: -1 } },
{ $limit: 1 },
])
Edit after feedback via chat
I grouped the documents by using the users array and basically just output all fields as in the initial document:
.aggregate([
{
$match: {
users: ObjectId("<UserID>")
}
},
{
$group: {
_id: "$users",
out: {
$top: {
output: {
_id: "$_id",
content: "$content",
fromUser: "$fromUser",
toUser: "$toUser",
users: "$users",
messageRead: "$messageRead",
createdAt: "$createdAt"
},
sortBy: {
createdAt: -1
}
}
}
}
},
{
"$replaceRoot": {
"newRoot": "$out"
}
}
])
In my Node API and MongoDB, I'm trying to make an endpoint to get all the posts associated with one username of a profile. In my Profile schema, I have a reference to the Post Schema and in my Post schema, I have a reference to the Username from Profile schema.
My issue I don't know how to get all the posts for that username. I did similarly but with embedded for the Experience schema but I'm not sure how to do that for the referenced collections.
Post model:
const { Connect } = require("../db");
const reactionSchema = {
likedBy: {
type: String,
unique: true,
sparse: true
}
};
const postSchema = {
text: {
type: String,
required: true,
unique: true,
sparse: false
},
username: {
type: Connect.Schema.Types.String,
ref: "Profile"
},
image: {
type: String,
default: "https://via.placeholder.com/150",
required: false
},
createdAt: {
type: Date,
default: Date.now,
required: false
},
updatedAt: {
type: Date,
default: Date.now,
required: false
},
reactions: [reactionSchema],
comments: {
type: Connect.Schema.Types.ObjectId,
ref: "Comment",
required: false
}
};
const collectionName = "post";
const postSchemaModel = Connect.Schema(postSchema);
const Post = Connect.model(collectionName, postSchemaModel);
module.exports = Post;
Profile model:
// Here defining profile model
// Embedded we have the Experience as []
const { Connect } = require("../db");
const { isEmail } = require("validator");
const postSchema = {
type: Connect.Schema.Types.ObjectId,
ref: "Post"
};
const experienceSchema = {
role: {
type: String,
required: true
},
company: {
type: String,
required: true
},
startDate: {
type: Date,
required: true
},
endDate: {
type: Date,
required: false
},
description: {
type: String,
required: false
},
area: {
type: String,
required: true
},
createdAt: {
type: Date,
default: Date.now,
required: false
},
updatedAt: {
type: Date,
default: Date.now,
required: false
},
username: {
type: String,
required: false
},
image: {
type: String,
required: false,
default: "https://via.placeholder.com/150"
}
};
const profileSchema = {
firstname: {
type: String,
required: true
},
surname: {
type: String,
required: true
},
email: {
type: String,
trim: true,
lowercase: true,
unique: true,
required: [true, "Email is required"],
validate: {
validator: string => isEmail(string),
message: "Provided email is invalid"
}
},
bio: {
type: String,
required: true
},
title: {
type: String,
required: true
},
area: {
type: String,
required: true
},
imageUrl: {
type: String,
required: false,
default: "https://via.placeholder.com/150"
},
username: {
type: String,
required: true,
unique: true
},
experience: [experienceSchema],
posts: [postSchema],
createdAt: {
type: Date,
default: Date.now,
required: false
},
updatedAt: {
type: Date,
default: Date.now,
required: false
}
};
const collectionName = "profile";
const profileSchemaModel = Connect.Schema(profileSchema);
const Profile = Connect.model(collectionName, profileSchemaModel);
module.exports = Profile;
I was able to make this for the embedded experience but not sure that correct for referenced collection:
const profileWithExperiences = await Student.aggregate([
{ $match: { username: res.username.username } },
{
$unwind: "$experience"
},
{
$match: {
"experience._id": new ObjectID(req.params.experienceId)
}
},
{
$project: {
username: 1,
experience: 1,
_id: 0
}
}
]);
I would like to see an example for referenced collections as it is confusing me how should I do that
[EDIT]
JSON for Profiles and Posts
{
"_id": ObjectId("5e2c98fc3d785252ce5b5693"),
"imageUrl": "https://i.pravatar.cc/300",
"firstname": "Jakos",
"surname": "Lemi",
"email": "lemi#email.com",
"bio": "My bio bio",
"title": "Senior IT developer",
"area": "Copenhagen",
"username": "Jakos",
"experience": [
{
"image": "https://via.placeholder.com/150",
"_id": ObjectId("5e3975f95fbeec9095ff3d2f"),
"role": "Developer",
"company": "Google",
"startDate": ISODate("2018-11-09T23:00:00.000Z"),
"endDate": ISODate("2019-01-05T23:00:00.000Z"),
"area": "Copenhagen",
"createdAt": ISODate("2020-02-04T13:47:37.167Z"),
"updatedAt": ISODate("2020-02-04T13:47:37.167Z")
},
{
"image": "https://via.placeholder.com/150",
"_id": ObjectId("5e3978bf5e399698e20c56d4"),
"role": "Developer",
"company": "IBM",
"startDate": ISODate("2018-11-09T23:00:00.000Z"),
"endDate": ISODate("2019-01-05T23:00:00.000Z"),
"area": "Copenhagen",
"createdAt": ISODate("2020-02-04T13:59:27.412Z"),
"updatedAt": ISODate("2020-02-04T13:59:27.412Z")
}
],
"createdAt": ISODate("2020-01-25T19:37:32.727Z"),
"updatedAt": ISODate("2020-02-04T23:14:37.122Z"),
"__v": NumberInt("0")
}
Post
{
"_id": ObjectId("5e3beb639e072afedd19dcef"),
"username": ObjectId("5e2c98fc3d785252ce5b5693"),
"image": "https://via.placeholder.com/150",
"text": "My awesome post",
"createdAt": ISODate("2020-02-06T10:33:07.22Z"),
"updatedAt": ISODate("2020-02-06T10:33:07.22Z"),
"reactions": [ ],
"__v": NumberInt("0")
}
Output expected:
{
"username": "Jakos",
"postsCount": [1],
"posts": [
{
"_id": ObjectId("5e3beb639e072afedd19dcef"),
"image": "https://via.placeholder.com/150",
"text": "My awesome post",
"createdAt": ISODate("2020-02-06T10:33:07.22Z"),
"updatedAt": ISODate("2020-02-06T10:33:07.22Z"),
"reactions": [ ],
"__v": NumberInt("0")
}
]
}
I want to see all the posts related to that username
You can use the $lookup aggregation to join collections.
db.profiles.aggregate([
{
$match: {
username: "Jakos"
}
},
{
$lookup: {
from: "posts", //the name of the posts collection, change this if it is different
localField: "_id",
foreignField: "username",
as: "posts"
}
},
{
$project: {
username: 1,
posts: 1,
postsCount: {
$size: "$posts"
},
_id: 0
}
}
])
Playground
For mongoose it should be like this in your app:
const profileWithExperiences = await Student.aggregate([
{ $match: { username: res.username.username } },
{
$unwind: "$experience"
},
{
$lookup: {
from: "posts", //the name of the posts collection, change this if it is different
localField: "_id",
foreignField: "username",
as: "posts"
}
},
{
$project: {
username: 1,
posts: 1,
postsCount: {
$size: "$posts"
},
_id: 0
}
}
]);
Try to get like this i am getting data from two table with the use of node and mongodb.
var param = {};
param['user_id']=id;
var search={ user_id:param.user_id,status: [ 'Pending', 'Accepted' ] };
var output={};
output = await JobRequest.find(search);
if(output !=0)
{
var JSon=await JobRequest.aggregate([
{$match: { user_id: {$gte:id}} },
{
"$project": {
"employee_id": {
"$toObjectId": "$employee_id"
},
"service_id": {
"$toObjectId": "$service_id"
},
"createdDate": {
"$toString": "$createdDate"
},
"chat_status": {
"$toString": "$chat_status"
},
"status": {
"$toString": "$status"
},
"delivery_address": {
"$toString": "$delivery_address"
},
"delivery_lat": {
"$toString": "$delivery_lat"
},
"delivery_lang": {
"$toString": "$delivery_lang"
},
}
},
{
$lookup:
{
from: "employees",
localField: "employee_id",
foreignField: "_id",
as: "employee_details"
}
},
{
$lookup:
{
from: "services",
localField: "service_id",
foreignField: "_id",
as: "service_details"
}
}
]);
My profile document is saved in my DB as the following:
{
"_id": {
"$oid": "5c3aa1de18ad682fb1444138"
},
"user": {
"$oid": "5c318f56e3224b15e0fdbd06"
},
"company": {
"info": {
"$oid": "5c318f56e3224b15e0fdbd07"
},
"position": "Stemuli"
},
"hometown": "Dallas",
"date": {
"$date": "2019-01-13T02:26:38.185Z"
},
"__v": 0
}
I am trying to populate the field company.info within the newly saved Profile.
new Profile(profileFields).save().then(profile => {
Profile.populate(profile, { path: "company.info" }, (err, p) => {
console.log(err);
console.log(p);
});
});
I get the following returned for the company field
company: {id: "5c318f56e3224b15e0fdbd07", position: "Stemuli"}
And the document that this id is linked to is the following:
{
"_id": {
"$oid": "5c318f56e3224b15e0fdbd07"
},
"employees": [
{
"$oid": "5c318f56e3224b15e0fdbd06"
}
],
"name": "Company",
"__v": 14
}
How can I get it to populate the actual company document instead of just the id?
Profile Schema
// Create Schema
const ProfileSchema = new Schema({
user: {
type: Schema.Types.ObjectId,
ref: "users"
},
company: {
id: { type: Schema.Types.ObjectId, ref: "industrypartners" },
position: { type: String }
},
work_experience: Array,
hometown: { type: String },
date: {
type: Date,
default: Date.now
}
});
module.exports = Profile = mongoose.model("profile", ProfileSchema);
Industry Partner Schema
// Create Schema
const IndustryPartnerSchema = new Schema({
name: {
type: String,
required: true
},
schools: [{ type: Schema.Types.ObjectId, ref: "schools" }]
});
module.exports = IndustryPartner = mongoose.model(
"industrypartner",
IndustryPartnerSchema
);
Try with this:
new Profile(profileFields).save().then(profile => {
Profile.populate(Profile, {
path: "company.info",
select: {
_id: 1,
employees: 1,
name: 1,
}
}, (err, p) => {
console.log(err);
console.log(p);
});
});
im using nodejs express and mongodb
this is part of my schema:
var UserSchema = mongoose.Schema({
friends: [{
type: mongoose.Schema.Types.ObjectId,
ref: "User",
unique: true
}],
sentRequests: [{
type: mongoose.Schema.Types.ObjectId,
ref: "User",
unique: true
}],
receivedRequests: [{
type: mongoose.Schema.Types.ObjectId,
ref: "User",
unique: true
}]
}
var User = mongoose.model('User', UserSchema);
i want to query if a user with a specefic id is in any array ** (friends, sentRequests or receivedRequests) **of another user :
i used this approach but I have to do this for 3 arrays and it's slow:
UserSchema.statics.relStatus = function(User1ID, User2ID) {
var User = this;
User.find({
_id: User1ID,
friends: {
_id: User2ID
}
}).then((err, res) => {
if (res) {
return ' they are friends';
}
});
You can try with following aggregation query (if you are using mongo 3.4 or higher):
User.aggregate([
{ $match: { _id: User1ID } },
{
$facet: {
friends: [{ $match: { friends: User2ID } }],
sentRequests: [{ $match: { sentRequests: User2ID } }],
receivedRequests: [{ $match: { receivedRequests: User2ID } }]
}
},
{
$project: {
relationship: {
$switch: {
branches: [
{ case: { $anyElementTrue: [ "$friends" ] }, then: "friends" },
{ case: { $anyElementTrue: [ "$sentRequests" ] }, then: "sentRequests" },
{ case: { $anyElementTrue: [ "$receivedRequests" ] }, then: "receivedRequests" },
],
default: false
}
}
}
}
])
Result will be object in following format {relationship: "<RELATIONSHIP_TYPE>"}
or {relationship: false} if they have no relationship.
First stage of the aggregation pipeline will match single document by _id (which is indexed by default), so you shouldnt have any performance issues.
In order to query for multiple field you can user '$or'.
User.find({
_id: User1ID,
{
$or: [
{friends: $in:[User2ID]},
{sentRequests: $in:[User2ID]},
{receivedRequests: $in:[User2ID]}
]
}
}).then((err, res) => {
if (res) {
return ' they are friends';
}
});
$or will return a user which have User2ID in either 'friends' or 'sentRequests' or 'receivedRequests'.
Read more about '$or' and '$in'
Hope this helps.
I have this schema for users where followers/followed is array and the reference the same schema
var userSchema = new Schema({
username: { type: String, unique: true, trim: true, required: true },
password: { type: String, required: true },
followers: [{ type: Schema.Types.ObjectId, ref: "users" }],
followed: [{ type: Schema.Types.ObjectId, ref: "users" }],
registered: { type: Date, default: Date.now },
admin: { type: Number, default: 0 }
});
What I am looking for to return the follow status, if the _id is contains in followed array give me for example follow_status: 1
[
{
$match: { username: new RegExp(username, "i") }
},
{
$unwind: "$followers"
},
{
$lookup: {
from: "users",
localField: "followers",
foreignField: "_id",
as: "info"
}
},
{
$unwind: "$info"
},
{
$project: {
info: {
_id: 1,
username: 1,
avatar: { $ifNull: ["$avatar", ""] },
fullname: { $ifNull: ["$fullname", ""] }
}
}
},
{
$replaceRoot: { newRoot: "$info" }
},
{
$limit: 1000
}
]
Current pipeliens result
[
{
"_id": "5a906653f52e66c9c7a23cb6",
"username": "User1"
},
{
"_id": "5a908eb564a726cf8ec7e0a3",
"username": "User2"
}
]