I have a Mongoose document (Mongoose 5.4.13, mongoDB 4.0.12):
var SkillSchema = new mongoose.Schema({
skill: { type: String },
count: { type: Number, default: 0 },
associatedUsers: [{ type : mongoose.Schema.Types.ObjectId, ref: 'User' }]
});
That I update as follows:
var query = { skill: req.body.skill };
var update = { $addToSet: { associatedUsers: req.params.id } };
var options = { upsert: true, new: true, setDefaultsOnInsert: true };
await skillSchema.findOneAndUpdate(query, update, options);
During this update, I would like to also update count to be equal to the length of associatedUsers.
Ideally I want this to happen at the same time as updating the other fields (i.e not in a subsequent update), either via a pre-hook or within findOneAndUpdate.
I've tried using a pre hook after schema definition:
SkillSchema.pre('findOneAndUpdate', async function(){
console.log("counting associated users");
this.count = this.associatedUsers.length;
next();
});
As well as using aggregate in my UPDATE route:
await skillSchema.aggregate([{ $project: { count: { $size: "$associatedUsers" } } } ])
But I can't get either to work.
Does anyone have any suggestions for how I could achieve this?
You could use $set like this in 4.2 which supports aggregation pipeline in update.
The first $set stage calculates a associatedUsers based on the previous and new value. $setUnion to keep the distinct associatedUsers values.
The second $set stage calculates tally based on the associatedUsers calculated in the previous stage.$size to calculate the length of associatedUsers values.
var query = {skill: req.body.skill};
var update = [{ $set: { "associatedUsers":{"$setUnion":[{"$ifNull":["$associatedUsers",[]]}, [req.params.id]] }}}, {$set:{tally:{ $size: "$associatedUsers" }}}];
var options = { upsert: true, new: true, setDefaultsOnInsert: true };
await skillSchema.findOneAndUpdate(query, update, options)
If any argument resolves to a value of null or refers to a field that is missing, $setUnion returns null. So just needed to safeguard our operation with $ifNull
About tally and associatedUsers.length
// define your schema object
var schemaObj = {
skill: { type: String },
associatedUsers: { type: Array }
};
// get the length of users
var lengthOfAsUsers = schemaObj.associatedUsers.length;
// add tally to schema object and set default to the length of users
schemaObj.tally = { type: Number, default: lengthOfAsUsers };
// and pass your schema object to mongoose.Schema
var SkillSchema = new mongoose.Schema(schemaObj);
module.exports = SkillSchema;
EDIT
you can update tally subsequently, but recommended solution would be to use this method
https://mongoosejs.com/docs/populate.html
const id = "nameSomeId";
SkillSchema.find({ _id: id }).then(resp => {
const tallyToUpdate = resp.associatedUsers.length;
SkillSchema.findOneAndUpdate({ _id: id }, { tally: tallyToUpdate }).then(
resp => {
console.log(resp);
}
);
});
The solution I have will only work on mongodb v 4.2 as it has option to use aggregate in the update and will only need one query as:
skillSchemafindOneAndUpdate(
{skill:"art"},
[
{ $set: {
associatedUsers:{
$cond:{
if: {$gte: [{$indexOfArray: ["$associatedUsers", mongoose.Types.ObjectId(req.params.id)]}, 0]},
then: "$associatedUsers",
else: { $cond:{
if: { $isArray: "$associatedUsers" },
then: {$concatArrays:["$associatedUsers",[mongoose.Types.ObjectId(req.params.id)]]},
else: [mongoose.Types.ObjectId(req.params.id)]
}}
}
}}},
{$set:{
associatedUsers:"$associatedUsers",
tally:{$size:"$associatedUsers"},
}}
],
{upsert:true,new:true}
)
ref: https://docs.mongodb.com/manual/reference/method/db.collection.update/#update-with-aggregation-pipeline
The "Group" field does not appear in the schema. On MongoDB Shell, these codes will work.
However, Mongoose will also give an error because the schema is validated.
Is the "Group" field a dynamic field? I think the problem with the schema will be solved.
var mongoose = require("mongoose");
var SkillSchema = new mongoose.Schema({
skill: { type: String },
tally: { type: Number, default: 0 },
associatedUsers: { type: Array },
group: { type: Array }
});
I am working on a MEAN stack application in which i defined a model using following schema:
var mappingSchema = new mongoose.Schema({
MainName: String,
Addr: String,
Mapping1: [Schema1],
Mappings2: [Schema2]
},
{collection : 'Mappings'}
);
I am displaying all this data on UI and Mapping1 & Mapping2 are displayed in the 2 tables where I can edit the values. What I am trying to do is once I update the values in table I should update them in database. I wrote put() api where I am getting these two updated mappings in the form of object but not able to update it in database. I tried using findAndModify() & findOneAndUpdate() but failed.
Here are the Schema1 & Schema2:
const Schema1 = new mongoose.Schema({
Name: String,
Variable: String
});
const Schema2 = new mongoose.Schema({
SName: String,
Provider: String
});
and my put api:
.put(function(req, res){
var query = {MainName: req.params.mainname};
var mapp = {Mapping1: req.params.mapping1, Mapping2: req.params.mapping2};
Mappings.findOneAndUpdate(
query,
{$set:mapp},
{},
function(err, object) {
if (err){
console.warn(err.message); // returns error if no matching object found
}else{
console.log(object);
}
});
});
Please suggest the best to way update those two arrays.
UPDATE :
I tried this
var mapp = {'Mapping2': req.params.mapping2};
Mappings.update( query ,
mapp ,
{ },
function (err, object) {
if (err || !object) {
console.log(err);
res.json({
status: 400,
message: "Unable to update" + err
});
} else {
return res.json(object);
}
});
what I got is
My array with size 3 is saved as String in Mapping2 array.
Please help. Stuck badly. :(
From Mongoose's documentation I believe there's no need to use $set. Just pass an object with the properties to update :
Mappings.findOneAndUpdate(
query,
mapp, // Object containing the keys to update
function(err, object) {...}
);
I have left my code for over a year and have ran NPM install and since it obviously has changed :)
My Query
var mongoose = require('mongoose'),
Clubs = mongoose.model('Clubs');
getNorsemanClubs: function(passData){
return new Promise(function (resolve) {
Clubs.find({norseman:true}, 'name teamID date norseman eleven').sort({ eleven : 'asc'})
.then(function(clubs){
console.info(clubs);
passData.clubs = clubs;
resolve(passData);
});
})
}
console.info(clubs); Output
Here you can see that it is returning the model rather than the results of the clubs.
My model
var mongoose = require('mongoose')
, Schema = mongoose.Schema;
/**
* User Schema
*/
var ClubsScheme = new Schema({
name: String,
teamID: { type: String, default: null },
date: { type: Date, default: Date.now},
norseman: {type: Boolean, default: false},
eleven: Number
})
mongoose.model('Clubs', ClubsScheme);
How can I get it return a list of the clubs?
The clubs table is full of match data. But I used to get a return from 'name teamID date norseman eleven' now I just get a return of :\
**Using exec()
You need to execute your find mongoose query method, by trailing your query with exec() method so that it return a Promise with your list values resolved, so change the following line:
Clubs.find({norseman:true}, 'name teamID date norseman eleven').sort({ eleven : 'asc'})
to:
Clubs.find({norseman:true}, 'name teamID date norseman eleven').sort({ eleven : 'asc'}).exec()
I am trying to remove an element through its _id from an array model in mongoose. The same technique is working elsewhere in my code, but here it fails to remove the element. After hours of trying to change various parts of it, I am finally posting it here because maybe my lack of sleep is the main reason. Can someone find out what i am doing wrong?
ABC.findOne({
'user': new ObjectId(req.decoded._id),
'activity.ride': new ObjectId(id)
}, {
'activity.$': 1
}, function(err, doc) {
if (doc !== null) {
for (var j = 0; j < doc.activity.length; j++) {
var request = JSON.parse(JSON.stringify(doc.activity[j]));
doc.activity.remove(request._id);
doc.save();
}
}
});
This is the model:
var activityItem = mongoose.Schema({
timestampValue: Number,
xabc: String,
full: Boolean,
comp: Boolean
});
var ABC = mongoose.Schema({
activity: [activityItem],
user: {
type: mongoose.Schema.ObjectId,
ref: 'User'
},
username: String
});
The $pull operator removes from an existing array all instances of a value or values that match a specified condition. And to remove element from array through findOneAndUpdate
ABC.findOneAndUpdate({'user': new ObjectId(req.decoded._id)},
{$pull: {activity: {_id: request._id}}},
{new: true},
function(err, a) {
if (err)
console.log(err);
else
console.log(a);
});
BTW, I did not find ride in the activityItem schema, so I remove the ride from query condition.
According to this mongodb article it is possible to auto increment a field and I would like the use the counters collection way.
The problem with that example is that I don't have thousands of people typing the data in the database using the mongo console. Instead I am trying to use mongoose.
So my schema looks something like this:
var entitySchema = mongoose.Schema({
testvalue:{type:String,default:function getNextSequence() {
console.log('what is this:',mongoose);//this is mongoose
var ret = db.counters.findAndModify({
query: { _id:'entityId' },
update: { $inc: { seq: 1 } },
new: true
}
);
return ret.seq;
}
}
});
I have created the counters collection in the same database and added a page with the _id of 'entityId'. From here I am not sure how to use mongoose to update that page and get the incrementing number.
There is no schema for counters and I would like it to stay that way because this is not really an entity used by the application. It should only be used in the schema(s) to auto increment fields.
Here is an example how you can implement auto-increment field in Mongoose:
var CounterSchema = Schema({
_id: {type: String, required: true},
seq: { type: Number, default: 0 }
});
var counter = mongoose.model('counter', CounterSchema);
var entitySchema = mongoose.Schema({
testvalue: {type: String}
});
entitySchema.pre('save', function(next) {
var doc = this;
counter.findByIdAndUpdate({_id: 'entityId'}, {$inc: { seq: 1} }, function(error, counter) {
if(error)
return next(error);
doc.testvalue = counter.seq;
next();
});
});
You can use mongoose-auto-increment package as follows:
var mongoose = require('mongoose');
var autoIncrement = require('mongoose-auto-increment');
/* connect to your database here */
/* define your CounterSchema here */
autoIncrement.initialize(mongoose.connection);
CounterSchema.plugin(autoIncrement.plugin, 'Counter');
var Counter = mongoose.model('Counter', CounterSchema);
You only need to initialize the autoIncrement once.
The most voted answer doesn't work. This is the fix:
var CounterSchema = new mongoose.Schema({
_id: {type: String, required: true},
seq: { type: Number, default: 0 }
});
var counter = mongoose.model('counter', CounterSchema);
var entitySchema = mongoose.Schema({
sort: {type: String}
});
entitySchema.pre('save', function(next) {
var doc = this;
counter.findByIdAndUpdateAsync({_id: 'entityId'}, {$inc: { seq: 1} }, {new: true, upsert: true}).then(function(count) {
console.log("...count: "+JSON.stringify(count));
doc.sort = count.seq;
next();
})
.catch(function(error) {
console.error("counter error-> : "+error);
throw error;
});
});
The options parameters gives you the result of the update and it creates a new document if it doesn't exist.
You can check here the official doc.
And if you need a sorted index check this doc
So combining multiple answers, this is what I ended up using:
counterModel.js
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
const counterSchema = new Schema(
{
_id: {type: String, required: true},
seq: { type: Number, default: 0 }
}
);
counterSchema.index({ _id: 1, seq: 1 }, { unique: true })
const counterModel = mongoose.model('counter', counterSchema);
const autoIncrementModelID = function (modelName, doc, next) {
counterModel.findByIdAndUpdate( // ** Method call begins **
modelName, // The ID to find for in counters model
{ $inc: { seq: 1 } }, // The update
{ new: true, upsert: true }, // The options
function(error, counter) { // The callback
if(error) return next(error);
doc.id = counter.seq;
next();
}
); // ** Method call ends **
}
module.exports = autoIncrementModelID;
myModel.js
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
const autoIncrementModelID = require('./counterModel');
const myModel = new Schema({
id: { type: Number, unique: true, min: 1 },
createdAt: { type: Date, default: Date.now },
updatedAt: { type: Date },
someOtherField: { type: String }
});
myModel.pre('save', function (next) {
if (!this.isNew) {
next();
return;
}
autoIncrementModelID('activities', this, next);
});
module.exports = mongoose.model('myModel', myModel);
Attention!
As hammerbot and dan-dascalescu pointed out this does not work if you remove documents.
If you insert 3 documents with id 1, 2 and 3 - you remove 2 and insert another a new one it'll get 3 as id which is already used!
In case you don't ever remove documents, here you go:
I know this has already a lot of answers, but I would share my solution which is IMO short and easy understandable:
// Use pre middleware
entitySchema.pre('save', function (next) {
// Only increment when the document is new
if (this.isNew) {
entityModel.count().then(res => {
this._id = res; // Increment count
next();
});
} else {
next();
}
});
Make sure that entitySchema._id has type:Number.
Mongoose version: 5.0.1.
This problem is sufficiently complicated and there are enough pitfalls that it's best to rely on a tested mongoose plugin.
Out of the plethora of "autoincrement" plugins at http://plugins.mongoosejs.io/, the best maintained and documented (and not a fork) is mongoose sequence.
I've combined all the (subjectively and objectively) good parts of the answers, and came up with this code:
const counterSchema = new mongoose.Schema({
_id: {
type: String,
required: true,
},
seq: {
type: Number,
default: 0,
},
});
// Add a static "increment" method to the Model
// It will recieve the collection name for which to increment and return the counter value
counterSchema.static('increment', async function(counterName) {
const count = await this.findByIdAndUpdate(
counterName,
{$inc: {seq: 1}},
// new: return the new value
// upsert: create document if it doesn't exist
{new: true, upsert: true}
);
return count.seq;
});
const CounterModel = mongoose.model('Counter', counterSchema);
entitySchema.pre('save', async function() {
// Don't increment if this is NOT a newly created document
if(!this.isNew) return;
const testvalue = await CounterModel.increment('entity');
this.testvalue = testvalue;
});
One of the benefits of this approach is that all the counter related logic is separate. You can store it in a separate file and use it for multiple models importing the CounterModel.
If you are going to increment the _id field, you should add its definition in your schema:
const entitySchema = new mongoose.Schema({
_id: {
type: Number,
alias: 'id',
required: true,
},
<...>
});
test.pre("save",function(next){
if(this.isNew){
this.constructor.find({}).then((result) => {
console.log(result)
this.id = result.length + 1;
next();
});
}
})
I didn't wan to use any plugin (an extra dependencie, initializing the mongodb connection apart from the one I use in the server.js, etc...) so I did an extra module, I can use it at any schema and even, I'm considering when you remove a document from the DB.
module.exports = async function(model, data, next) {
// Only applies to new documents, so updating with model.save() method won't update id
// We search for the biggest id into the documents (will search in the model, not whole db
// We limit the search to one result, in descendant order.
if(data.isNew) {
let total = await model.find().sort({id: -1}).limit(1);
data.id = total.length === 0 ? 1 : Number(total[0].id) + 1;
next();
};
};
And how to use it:
const autoincremental = require('../modules/auto-incremental');
Work.pre('save', function(next) {
autoincremental(model, this, next);
// Arguments:
// model: The model const here below
// this: The schema, the body of the document you wan to save
// next: next fn to continue
});
const model = mongoose.model('Work', Work);
module.exports = model;
Hope it helps you.
(If this Is wrong, please, tell me. I've been having no issues with this, but, not an expert)
Here is a proposal.
Create a separate collection to holds the max value for a model collection
const autoIncrementSchema = new Schema({
name: String,
seq: { type: Number, default: 0 }
});
const AutoIncrement = mongoose.model('AutoIncrement', autoIncrementSchema);
Now for each needed schema, add a pre-save hook.
For example, let the collection name is Test
schema.pre('save', function preSave(next) {
const doc = this;
if (doc.isNew) {
const nextSeq = AutoIncrement.findOneAndUpdate(
{ name: 'Test' },
{ $inc: { seq: 1 } },
{ new: true, upsert: true }
);
nextSeq
.then(nextValue => doc[autoIncrementableField] = nextValue)
.then(next);
}
else next();
}
As findOneAndUpdate is an atomic operation, no two updates will return same seq value. Thus each of your insertion will get an incremental seq regardless of number of concurrent insertions. Also this can be extended to more complex auto incremental logic and the auto increment sequence is not limited to Number type
This is not a tested code. Test before you use until I make a plugin for mongoose.
Update I found that this plugin implemented related approach.
The answers seem to increment the sequence even if the document already has an _id field (sort, whatever). This would be the case if you 'save' to update an existing document. No?
If I'm right, you'd want to call next() if this._id !== 0
The mongoose docs aren't super clear about this. If it is doing an update type query internally, then pre('save' may not be called.
CLARIFICATION
It appears the 'save' pre method is indeed called on updates.
I don't think you want to increment your sequence needlessly. It costs you a query and wastes the sequence number.
I had an issue using Mongoose Document when assigning value to Schema's field through put(). The count returns an Object itself and I have to access it's property.
I played at #Tigran's answer and here's my output:
// My goal is to auto increment the internalId field
export interface EntityDocument extends mongoose.Document {
internalId: number
}
entitySchema.pre<EntityDocument>('save', async function() {
if(!this.isNew) return;
const count = await counter.findByIdAndUpdate(
{_id: 'entityId'},
{$inc: {seq: 1}},
{new: true, upsert: true}
);
// Since count is returning an array
// I used get() to access its child
this.internalId = Number(count.get('seq'))
});
Version: mongoose#5.11.10
None of above answer works when you have unique fields in your schema
because unique check at db level and increment happen before db level validation, so you may skip lots of numbers in auto increments like above solutions
only in post save can find if data already saved on db or return error
schmea.post('save', function(error, doc, next) {
if (error.name === 'MongoError' && error.code === 11000) {
next(new Error('email must be unique'));
} else {
next(error);
}
});
https://stackoverflow.com/a/41479297/10038067
that is why none of above answers are not like atomic operations auto increment in sql like dbs
I use together #cluny85 and #edtech.
But I don't complete finish this issues.
counterModel.findByIdAndUpdate({_id: 'aid'}, {$inc: { seq: 1} }, function(error,counter){
But in function "pre('save...) then response of update counter finish after save document.
So I don't update counter to document.
Please check again all answer.Thank you.
Sorry. I can't add comment. Because I am newbie.
var CounterSchema = Schema({
_id: { type: String, required: true },
seq: { type: Number, default: 0 }
});
var counter = mongoose.model('counter', CounterSchema);
var entitySchema = mongoose.Schema({
testvalue: { type: String }
});
entitySchema.pre('save', function(next) {
if (this.isNew) {
var doc = this;
counter.findByIdAndUpdate({ _id: 'entityId' }, { $inc: { seq: 1 } }, { new: true, upsert: true })
.then(function(count) {
doc.testvalue = count.seq;
next();
})
.catch(function(error) {
throw error;
});
} else {
next();
}
});