This question already has answers here:
Mongoose nested query on Model by field of its referenced model
(3 answers)
Closed 8 years ago.
I have a query that get user posts and I wish to show only the posts of the Country selected by visitor.
So far I'm trying to do something like this:
var country = req.query.country || req.session.country || { $ne: '' };
Posts.find({})
.populate('_creator')
.where('_creator.country').equals(country)
.exec(function(err, posts) {
console.log(posts);
});
Unfortunately it doesn't work.
How can I have a query similar to this?
EDIT:
This is the Posts Schema:
var postsSchema = new mongoose.Schema({
_creator: { type: mongoose.Schema.Types.ObjectId, ref: 'User' },
text: { type: String, default: '' },
created_at: Date
});
You can't include a populated field in your query because populate is executed as a separate query after the initial query completes.
One way to efficiently perform this type of query is to first look up the ids of the users of the selected country and then query for the posts from those users.
// Get the _ids of the users of the selected country.
User.find({country: country}, {_id: 1}, function(err, users) {
// Map the user docs into an array of just the _ids
var ids = users.map(function(user) { return user._id; });
// Get the posts whose _creator is in that set of ids
Post.find({_creator: {$in: ids}}).populate('_creator').exec(function(err, posts) {
// posts contains your answer
});
});
Related
I have these two 3 models User, Product and Orders and are also has references to each other.
My Orders Schema:
const orderSchema = Schema({
buyerId:{
type: Schema.Types.ObjectId,
ref: 'User'
},
totalAmount: {
type: Number,
required: [true, "description is required"]
},
createdOn: {
type: Date,
default: new Date()
},
items:[{type:Schema.Types.ObjectId, ref: 'Product'}]})
I'm trying to use populate() like this:
Order.find()
.populate('buyerId')//Reference to User Model
.populate('items')// Reference to Product Model
.exec(function (err, result){
console.log(result);// RETURNS ONLY buyerId populated
console.log(result.buyerId.name);//Successfully references to my User model and prints name
console.log(result.items);//Prints Undefined
})
You can see my console log above and what it returns is only the populated buyerId(only got the reference from my User model)
Seems like my populate('items') doesnt work at all. The items field contains array of IDs, where the IDs are those of products. I need to reference to User and Product both. I'm just following the documentation in mongoose, I don't know what I might be doing wrong.
use aggregate
Order.aggregate([
{ $match:{ user:"sample_id"
}
},
{$lookup:{
from:'users', // users collection name
localField:'buyerId',
foreignField:'_id',
as:'buyerId'
}},
{
$lookup:{
from:'items', //items collection name
localField:'items',
foreignField:'_id',
as:'items'
}
},
])
This question already has an answer here:
Update array inside of Mongo document doesn't work
(1 answer)
Closed 2 years ago.
I have a Users collection, each document has an "push_subscriptions" property. The problem is that I can't add a new element inside of it. Mongo updates "updatedAt" date but my array stays the same. I tried several approaches, but nothing worked out. My last try was with $push operator.
Here's what I tried:
const { user_id } = req.params; // Getting id normally
const subscription = req.body; // Getting subscription object normally
const updated_user = await UserModel.findByIdAndUpdate(user_id,
{
$push: {
push_subscriptions: subscription // Should add the subscription to array
}
},
{ new: true }).exec();
console.log(updated_user); // But console shows that the array is still empty
Here is the User's schema's push_subscription part:
push_subscriptions: {
type: Array,
},
Element I want to add to that array:
{"endpoint":"https://fcm.googleapis.com/fcm/send/dpH5lCsTSSM:APA91bHqjZxM0VImWWqDRN7U0a3AycjUf4O-byuxb_wJsKRaKvV_iKw56s16ekq6FUqoCF7k2nICUpd8fHPxVTgqLunFeVeB9lLCQZyohyAztTH8ZQL9WCxKpA6dvTG_TUIhQUFq_n",
"keys": {
"p256dh":"BLQELIDm-6b9Bl07YrEuXJ4BL_YBVQ0dvt9NQGGJxIQidJWHPNa9YrouvcQ9d7_MqzvGS9Alz60SZNCG3qfpk=",
"auth":"4vQK-SvRAN5eo-8ASlrwA=="
}
}
can you try it with this piece of code?
UserModel.updateOne({_id: user_id},{ $addToSet: { push_subscriptions: subscription } },async(err,raw)=>{})
and update your model as
push_subscriptions:[
{
_id: false ,
endpoint:{
type: String, required: false
},
keys:{
type: String, required: false
}
}
],
and use the command for update .
i hope it helps
I've got a chat schema that looks like that:
var chatSchema = new mongoose.Schema({
users: [{
type: mongoose.Schema.Types.ObjectId,
required: true
}]
});
It contains array of user IDs.
Now I want to find one chat document that contains an array of two user IDs.
At the beginning I tried to do this:
Chat.findOne({ users: { $in: [req.user_id, receiver._id] }})
.then(chat => { })
But it seems that every time it gives me the chat that contains at least one of the IDs I mentioned in the query.
So I've tried to change it to this but with no luck:
Chat.findOne()
.where({ users: { $in: [req.user_id] }})
.where({ users: { $in: [receiver._id] }})
.then(chat => { })
I need to find the chat that contains both of the user ID's inside the users array otherwise I expect for a null value.
How can I achieve this goal?
Thanks!
This is the way $in works - returns the document when at least one value matches. You should use $all instead:
Chat.findOne({ users: { $all: [req.user_id, receiver._id] }})
I am creating an app where a job is created and that job's id is added to another collection (client) so the job can be referenced from the client itself. I have been able to add the job's id to the client's collection so far, but I am having trouble figuring out how to remove the job's id from the client's collection if the job is deleted. This is because the id is stored as a sub-collection within the client. The code I am trying to get to work is below:
// delete
app.delete("/jobs/:id", function(req, res){
Client.find({jobs._id: req.params.id}, function (err, foundClient){ //This part doesn't work
if (err) {
console.log(err);
} else {
// Add id identifier to Client
foundClient.jobs.pull(req.params.id);
foundClient.save();
}
});
// Delete Job
Job.findByIdAndRemove(req.params.id, function(err, deletedJob){
if (err){
console.log(err)
} else {
// Redirect
res.redirect("/jobs");
}
});
});
I am trying to get the logic of this part to work:
Client.find({jobs._id: req.params.id},
Here is the Client Schema
// =======================Client Schema
var clientSchema = new mongoose.Schema({
organization_name: String,
first_name: String,
middle_name: String,
last_name: String,
email_address: String,
phone_number: String,
street: String,
city: String,
state: String,
zip: String,
description: String,
active: {type: Boolean, deafult: true},
date_added: {type: Date, default: Date.now},
transactions: [{type: mongoose.Schema.Types.ObjectID, ref: "Transaction"}],
jobs: [{type: mongoose.Schema.Types.ObjectID, ref: "Job"}]
});
module.exports = mongoose.model("Client", clientSchema);
Basically, what I am trying to tell it to do is find the Client where the client's jobs array contains an id equal to the id of the job being deleted. Of course, this syntax is incorrect, so it does not work. I have not been able to find documentation that explains how I would be able to do this. Is there a more straightforward way of doing this, the way I am writing it out here? I know that I can query the db this way if the job itself was not an array and only contained one singular variable. Is there a way to do this or do I need to write a completely separate looping function to get this to work? Thank you.
jobs is an array of ids, so to find some documents in Client collection that have req.params.id in the jobs array, the query should be something like this
Client.find({jobs: req.params.id})
this will return an array of documents, each document has an array of jobs Ids
If you are sure that the req.params.id exists only in one document, you can use findOne instead of find, and this will return only one document with an array of jobs Ids
this is regarding the find part
regarding the remove job Id from jobs array, we can use one of the following methods
1- as you suggested, we can find the clients documents that have this job Id first, then remove this id from all the jobs arrays in all matching documents
like this
Client.find({ jobs: req.params.id }, async function (err, foundClients) {
if (err) {
console.log(err);
} else {
// loop over the foundClients array then update the jobs array
for (let i = 0; i < foundClients.length; i++) {
// filter the jobs array in each client
foundClients[i].jobs = foundClients[i].jobs || []; // double check the jobs array
foundClients[i].jobs = foundClients[i].jobs.filter(jobId => jobId.toString() !== req.params.id.toString());
// return all the jobs Ids that not equal to req.params.id
// convert both jobId and req.params.id to string for full matching (type and value)
await foundClients[i].save(); // save the document
}
}
});
2- we can use $pull array update operator to update the jobs array directly
something like this
Client.updateMany(
{ jobs: req.params.id }, // filter part
{
$pull: { jobs: { $in: [req.params.id] } } // update part
},
function (err) {
if (err) {
console.log(err);
} else {
console.log('job id removed from client documents successfully');
}
}
);
hope it helps
I have the following schemas for the document Folder:
var permissionSchema = new Schema({
role: { type: String },
create_folders: { type: Boolean },
create_contents: { type: Boolean }
});
var folderSchema = new Schema({
name: { type: string },
permissions: [ permissionSchema ]
});
So, for each Page I can have many permissions. In my CMS there's a panel where I list all the folders and their permissions. The admin can edit a single permission and save it.
I could easily save the whole Folder document with its permissions array, where only one permission was modified. But I don't want to save all the document (the real schema has much more fields) so I did this:
savePermission: function (folderId, permission, callback) {
Folder.findOne({ _id: folderId }, function (err, data) {
var perm = _.findWhere(data.permissions, { _id: permission._id });
_.extend(perm, permission);
data.markModified("permissions");
data.save(callback);
});
}
but the problem is that perm is always undefined! I tried to "statically" fetch the permission in this way:
var perm = data.permissions[0];
and it works great, so the problem is that Underscore library is not able to query the permissions array. So I guess that there's a better (and workgin) way to get the subdocument of a fetched document.
Any idea?
P.S.: I solved checking each item in the data.permission array using a "for" loop and checking data.permissions[i]._id == permission._id but I'd like a smarter solution, I know there's one!
So as you note, the default in mongoose is that when you "embed" data in an array like this you get an _id value for each array entry as part of it's own sub-document properties. You can actually use this value in order to determine the index of the item which you intend to update. The MongoDB way of doing this is the positional $ operator variable, which holds the "matched" position in the array:
Folder.findOneAndUpdate(
{ "_id": folderId, "permissions._id": permission._id },
{
"$set": {
"permissions.$": permission
}
},
function(err,doc) {
}
);
That .findOneAndUpdate() method will return the modified document or otherwise you can just use .update() as a method if you don't need the document returned. The main parts are "matching" the element of the array to update and "identifying" that match with the positional $ as mentioned earlier.
Then of course you are using the $set operator so that only the elements you specify are actually sent "over the wire" to the server. You can take this further with "dot notation" and just specify the elements you actually want to update. As in:
Folder.findOneAndUpdate(
{ "_id": folderId, "permissions._id": permission._id },
{
"$set": {
"permissions.$.role": permission.role
}
},
function(err,doc) {
}
);
So this is the flexibility that MongoDB provides, where you can be very "targeted" in how you actually update a document.
What this does do however is "bypass" any logic you might have built into your "mongoose" schema, such as "validation" or other "pre-save hooks". That is because the "optimal" way is a MongoDB "feature" and how it is designed. Mongoose itself tries to be a "convenience" wrapper over this logic. But if you are prepared to take some control yourself, then the updates can be made in the most optimal way.
So where possible to do so, keep your data "embedded" and don't use referenced models. It allows the atomic update of both "parent" and "child" items in simple updates where you don't need to worry about concurrency. Probably is one of the reasons you should have selected MongoDB in the first place.
In order to validate subdocuments when updating in Mongoose, you have to 'load' it as a Schema object, and then Mongoose will automatically trigger validation and hooks.
const userSchema = new mongoose.Schema({
// ...
addresses: [addressSchema],
});
If you have an array of subdocuments, you can fetch the desired one with the id() method provided by Mongoose. Then you can update its fields individually, or if you want to update multiple fields at once then use the set() method.
User.findById(userId)
.then((user) => {
const address = user.addresses.id(addressId); // returns a matching subdocument
address.set(req.body); // updates the address while keeping its schema
// address.zipCode = req.body.zipCode; // individual fields can be set directly
return user.save(); // saves document with subdocuments and triggers validation
})
.then((user) => {
res.send({ user });
})
.catch(e => res.status(400).send(e));
Note that you don't really need the userId to find the User document, you can get it by searching for the one that has an address subdocument that matches addressId as follows:
User.findOne({
'addresses._id': addressId,
})
// .then() ... the same as the example above
Remember that in MongoDB the subdocument is saved only when the parent document is saved.
Read more on the topic on the official documentation.
If you don't want separate collection, just embed the permissionSchema into the folderSchema.
var folderSchema = new Schema({
name: { type: string },
permissions: [ {
role: { type: String },
create_folders: { type: Boolean },
create_contents: { type: Boolean }
} ]
});
If you need separate collections, this is the best approach:
You could have a Permission model:
var mongoose = require('mongoose');
var PermissionSchema = new Schema({
role: { type: String },
create_folders: { type: Boolean },
create_contents: { type: Boolean }
});
module.exports = mongoose.model('Permission', PermissionSchema);
And a Folder model with a reference to the permission document.
You can reference another schema like this:
var mongoose = require('mongoose');
var FolderSchema = new Schema({
name: { type: string },
permissions: [ { type: mongoose.Schema.Types.ObjectId, ref: 'Permission' } ]
});
module.exports = mongoose.model('Folder', FolderSchema);
And then call Folder.findOne().populate('permissions') to ask mongoose to populate the field permissions.
Now, the following:
savePermission: function (folderId, permission, callback) {
Folder.findOne({ _id: folderId }).populate('permissions').exec(function (err, data) {
var perm = _.findWhere(data.permissions, { _id: permission._id });
_.extend(perm, permission);
data.markModified("permissions");
data.save(callback);
});
}
The perm field will not be undefined (if the permission._id is actually in the permissions array), since it's been populated by Mongoose.
just try
let doc = await Folder.findOneAndUpdate(
{ "_id": folderId, "permissions._id": permission._id },
{ "permissions.$": permission},
);