Set or create embedded document in Mongoose - mongodb

I have a a schema as follows:
/**
* Answer Schema
*/
var AnswerSchema = new Schema({
answer: Number,
owner_id: Schema.Types.ObjectId
});
/**
* Poll Schema
*/
var PollSchema = new Schema({
question: { type: String, required: true, trim: true },
choices: [ { type: String, required: true, trim: true} ],
answers: [AnswerSchema]
});
How do I set an answer for a given poll_id and the owner_id of the person answering the poll?

The term "set or create" sort of opens this up a bit.
Essentially you will add (create) new items in arrays using the $push operator with .update(), or otherwise with a standard JavaScript array push once you have the current document after a .find().
But considering you might want to "update" an existing answer for a given owner then it's possibly a two step operation. If not then you just want the "update" using the $push.
PollSchema.update(
{ "_id": poll_id, "answers.owner_id": owner_id }
{ "$set":{ "answers.answer": value } },
function(err,numAffected) {
if (err)
throw err; // or whatever handling
// If this didn't modify anything then $push a document
if ( numAffected != 0 ) {
PollSchema.update(
{ "_id": poll_id },
{ "$push": {
"answers": {
"owner_id": owner_id,
"answer": value
}
}},
function(err, numAffected) {
// more things in here
}
);
}
);
Or again, if you do not care about having more than one answer per "owner" then just use the $push update.

Related

Editing specific element of an array of a particular collection - mongoDb

I am new to mongoDb. I have created a collection named task that has comments field which is array along with other fields. I need to edit specific comment of the task. There is a edit button in each comment. Both task id and comment id are available. Now how to edit specific comment of the task?
Thanks in advance
task api
{
"status":true,
"task":[
{
"_id":"61dfef323a6ee474c4eba926",
"description":"hello there",
"title":"hello",
"comments":[
{
"comment_id":1,
"username":"test",
"comment":"abcd",
"status":true,
},
{
"comment_id":2,
"username":"test",
"comment":"abcdsdfsdf",
"status":true,
}
],
"createdAt":"2022-01-13T09:21:54.795Z",
"updatedAt":"2022-01-13T09:21:54.795Z",
"__v":0
}
]
}
Task model schema
const taskSchema = new Schema({
title: { type: String, required: true },
description: { type: String, required: true },
comments: [Object],
}, {
timestamps: true,
});
I tried using $set but I don't know how to use it in the inner array.
router.route('./comments/edit').post((req, res) => {
const commentId = req.body.commentId;
const taskId = req.body.postId;
const comment = req.body.editedComment;
const updatedAt = new Date();
Task.updateOne(
{ _id: taskId},
{
//what to do here?
// $set: { comments: [ {'comment_id': commentId} ]},
}
)
.then((response) => res.json({ status: true, msg: 'Comment Edited!' }))
.catch(err => res.json({ status: false, msg: err }));
});
Thanks in advance.
This is how to do best:
db.collection.update({
status: true
},
{
$set: {
"task.$[x].comments.$[y].username": "New Name"
}
},
{
arrayFilters: [
{
"x._id": "61dfef323a6ee474c4eba926"
},
{
"y.comment_id": 2
}
]
})
Explained:
Define x and y as arrayFIlters in the update statement.
In the $set statement provide the x & y filters to identify the specific comment for update.
In the example I update the username , but you can update any other value from the targeted array subelement addressed by x & y.
playground
And here is how to update two values at same time in the same nested array element.

GraphQL Mutation Updating Users Followers with Mongoose/MongodDB - $set is empty error

I have this mutation set up:
followUser: {
type: UserType,
args: {
_id: { type: GraphQLString },
firebaseUid: { type: GraphQLString },
following: { type: new GraphQLList(GraphQLString)},
},
resolve(parentValue, { firebaseUid, _id, following}) {
const update = {
$set: { "following": [firebaseUid] },
$push: { "following": { firebaseUid } }
}
return UserSchema.findOneAndUpdate(
{ _id },
update,
{new: true, upsert: true}
)
}
},
I'm trying to add new followers into my graphql user's collection. My user model:
const UserSchema = new Schema(
{
firebaseUid: String,
following: [{ type: Schema.Types.ObjectId, ref: 'User' }],
followers: [{ type: Schema.Types.ObjectId, ref: 'User' }],
},
{ timestamps: true }
);
module.exports = mongoose.model("User", UserSchema);
So at first, the user doesn't have any followers, so it won't have that field yet. When user adds someone to their friends list, thats when the field will appear in mongodb. Right now I'm getting this error:
"message": "'$set' is empty. You must specify a field like so: {$set: {<field>: ...}}",
I'm not sure if I'm doing the $set correctly.
The UserType
const UserType = new GraphQLObjectType({
name: "User",
fields: () => ({
_id: { type: GraphQLString },
firebaseUid: { type: GraphQLString },
following: { type: new GraphQLList(GraphQLString) },
followers: { type: new GraphQLList(GraphQLString) },
...
})
});
edit:
current mongodb data collection:
_id: ObjectId("5e5c24111c9d4400006d0001")
name: "Mr. Smith"
username: "mrsmith"
after running the update
_id: ObjectId("5e5c24111c9d4400006d0001")
name: "Mr. Smith"
username: "mrsmith"
following: ["fdsaduybfeaf323dfa"] // <-- this gets added
Currently mongooses validator is rejecting the update. To fix this you need the following:
You only need to $push since it will automatically create an array if the property does not exist
You should remove the extra { } around the firebaseUid in the $push because otherwise the following array will contain objects with a firebaseUid property instead of directly containing the Uid (or would if the schema validator allowed it)
Mongo ObjectIds can only be converted from strings when they are 12-byte hexadecimal, and firebaseUid is not, so the schema should be typed to String instead of ObjectId as the validator will reject the field for update otherwise.

Mongoose findOneAndUpdate with $addToSet pushes duplicate

I have a schema such as
listSchema = new Schema({
...,
arts: [
{
...,
art: { type: Schema.Types.ObjectId, ref: 'Art', required: true },
note: Number
}
]
})
My goal is to find this document, push an object but without duplicate
The object look like
var art = { art: req.body.art, note: req.body.note }
The code I tried to use is
List.findOneAndUpdate({ _id: listId, user: req.myUser._id },
{ $addToSet: { arts: art} },
(err, list) => {
if (err) {
console.error(err);
return res.status(400).send()
} else {
if (list) {
console.log(list)
return res.status(200).json(list)
} else {
return res.status(404).send()
}
}
})
And yet there are multiple entries with the same Art id in my Arts array.
Also, the documentation isn't clear at all on which method to use to update something. Is this the correct way ? Or should I retrieve and then modify my object and .save() it ?
Found a recent link that came from this
List.findOneAndUpdate({ _id: listId, user: req.user._id, 'arts.art': artId }, { $set: { 'arts.$[elem]': artEntry } }, { arrayFilters: [{ 'elem.art': mongoose.Types.ObjectId(artId) }] })
artworkEntry being my modifications/push.
But the more I'm using Mongoose, the more it feels they want you to use .save() and modify the entries yourself using direct modification.
This might cause some concurrency but they introduced recently a, option to use on the schema { optimisticConcurrency: true } which might solve this problem.

Insert default values not working mongodb

I am using mongoose version 5.2.5 and here is the sample model of my order
....
let PlaceOrderSchema = new mongoose.Schema({
any: {}
}, { strict: false },
{ timestamps: { updatedAt: 'last_updated', createdAt: 'created' });
I am using the above model in main script with mongoose save and findOneAndUpdate.
In our production system , we are seeing many document that does not have last_updated key missing in the save document.
Here are sample code of the mongoose save method and findOneAndUpdate in our main script.We are seeing some of the documents have updated_at keys while very few of them does not have it while saving the document
let orderModel = require('./orderModel');
let newOrder = {
order_no: 1234
};
//save usage code
(new Order(newOrder).save({lean: true}, ()=> {
//do...something
}));
//findOneAndUpdate usage Code
let orderNo = 123
OrderModel.findOneAndUpdate({ order_no: orderNo },
{
$set: { items: [{product_id: 'abc', quantity: 1}] },
},
{ new: true, upsert: true },
(err, res) => {
//do_something
});
Can any one share why we have few documents are getting saved without updated_at?
You need to use option setDefaultsOnInsert: true during the update operation.
Docs
By default, mongoose only applies defaults when you create a new
document. It will not set defaults if you use update() and
findOneAndUpdate(). However, mongoose 4.x lets you opt-in to this
behavior using the setDefaultsOnInsert option.
OrderModel.findOneAndUpdate(
{ order_no: orderNo },
{ $set: { items: [{ product_id: "abc", quantity: 1 }] }},
{ new: true, upsert: true, setDefaultsOnInsert: true }
)

auto increment ids in mongoose

How do I have autoincrement ids in mongoose? I want my ids to start like 1, 2, 3, 4, not the weird id numbers mongodb creates for you?
Here's my schema:
var PortfolioSchema = mongoose.Schema({
url: String,
createTime: { type: Date, default: Date.now },
updateTime: { type: Date, default: Date.now },
user: {type: Schema.Types.ObjectId, ref: 'User'}
});
Use mongoose-auto-increment:
https://github.com/codetunnel/mongoose-auto-increment
var mongoose = require('mongoose');
var autoIncrement = require('mongoose-auto-increment');
var connection = ....;
autoIncrement.initialize(connection);
var PortfolioSchema = new mongoose.Schema({
url: String,
createTime: { type: Date, default: Date.now },
updateTime: { type: Date, default: Date.now },
user: {type: Schema.Types.ObjectId, ref: 'User'}
});
//Auto-increment
PortfolioSchema.plugin(autoIncrement.plugin, { model: 'Portfolio' });
module.exports = mongoose.model('Portfolio', PortfolioSchema);
Or if you prefer to use an additional field instead of overriding _id, just add the field and list it in the auto-increment initialization:
var PortfolioSchema = new mongoose.Schema({
portfolioId: {type: Number, required: true},
url: String,
createTime: { type: Date, default: Date.now },
updateTime: { type: Date, default: Date.now },
user: {type: Schema.Types.ObjectId, ref: 'User'}
});
//Auto-increment
PortfolioSchema.plugin(autoIncrement.plugin, { model: 'Portfolio', field: 'portfolioId' });
If you want to have a incrementing numeric value in _id then the basic process is you are going to need something to return that value from a store somewhere. One way to do this is use MongoDB itself to store data that holds the counters for the _id values for each collection, which is described within the manual itself under Create and Auto-Incrementing Sequence Field.
Then as you create each new item, you use the implemented function to get that "counter" value, and use it as the _id in your document.
When overriding the default behavior here, mongoose requires that you both specify the _id and it's type explicitly with something like _id: Number and also that you tell it to no longer automatically try to supply an ObjectId type with { "_id": false } as an option on the schema.
Here's a working example in practice:
var async = require('async'),
mongoose = require('mongoose'),
Schema = mongoose.Schema;
mongoose.connect('mongodb://localhost/test');
var counterSchema = new Schema({
"_id": String,
"counter": { "type": Number, "default": 1 }
},{ "_id": false });
counterSchema.statics.getNewId = function(key,callback) {
return this.findByIdAndUpdate(key,
{ "$inc": { "counter": 1 } },
{ "upsert": true, "new": true },
callback
);
};
var sampleSchema = new Schema({
"_id": Number,
"name": String
},{ "_id": false });
var Counter = mongoose.model( 'Counter', counterSchema ),
ModelA = mongoose.model( 'ModelA', sampleSchema ),
ModelB = mongoose.model( 'ModelB', sampleSchema );
async.series(
[
function(callback) {
async.each([Counter,ModelA,ModelB],function(model,callback) {
model.remove({},callback);
},callback);
},
function(callback) {
async.eachSeries(
[
{ "model": "ModelA", "name": "bill" },
{ "model": "ModelB", "name": "apple" },
{ "model": "ModelA", "name": "ted" },
{ "model": "ModelB", "name": "oranage" }
],
function(item,callback) {
async.waterfall(
[
function(callback) {
Counter.getNewId(item.model,callback);
},
function(counter,callback) {
mongoose.model(item.model).findByIdAndUpdate(
counter.counter,
{ "$set": { "name": item.name } },
{ "upsert": true, "new": true },
function(err,doc) {
console.log(doc);
callback(err);
}
);
}
],
callback
);
},
callback
);
},
function(callback) {
Counter.find().exec(function(err,result) {
console.log(result);
callback(err);
});
}
],
function(err) {
if (err) throw err;
mongoose.disconnect();
}
);
For convience this implements a static method on the model as .getNewId() which just descriptively wraps the main function used in .findByIdAndUpdate(). This is a form of .findAndModify() as mentioned in the manual page section.
The purpose of this is that it is going to look up a specific "key" ( actually again the _id ) in the Counter model collection and perform an operation to both "increment" the counter value for that key and return the modified document. This is also aided with the "upsert" option, since if no document yet exists for the requested "key", then it will be created, otherwise the value will be incremented via $inc, and it always is so the default will be 1.
The example here shows that two counters are being maintained independently:
{ _id: 1, name: 'bill', __v: 0 }
{ _id: 1, name: 'apple', __v: 0 }
{ _id: 2, name: 'ted', __v: 0 }
{ _id: 2, name: 'oranage', __v: 0 }
[ { _id: 'ModelA', __v: 0, counter: 2 },
{ _id: 'ModelB', __v: 0, counter: 2 } ]
First listing out each document as it is created and then displaying the end state of the "counters" collection which holds the last used values for each key that was requested.
Also note those "weird numbers" serves a specific purpose of always being guranteed to be unique and also always increasing in order. And note that they do so without requiring another trip to the database in order to safely store and use an incremented number. So that should be well worth considering.