I have the following two schemas and models:
var Customer = new Schema({
name: String,
jobs: [{ type: Schema.Types.ObjectId, ref: 'Job' }]
});
var Job = new Schema({
title: String,
customer: { type: Schema.Types.ObjectId, ref: 'Customer' }
});
var CustomerModel = mongoose.model('Customer', Customer);
var JobModel = mongoose.model('Job', Job);
job documents have a reference to the customer document via _id, and the customer document also contains an array of all the jobs _id's.
When I delete a job I need to delete the corresponding _id from the Customer.jobs array.
Here is the route I have - the job gets deleted but I cannot remove it's id from the array
app.delete('/api/jobs/:jobId', function(req, res){
return JobModel.findById(req.params.jobId, function(err, job){
return job.remove(function(err){
if(!err){
CustomerModel.update({_id: job.customer._id}, {$pull : {'customer.jobs' : job.customer._id}}, function(err, numberAffected){
console.log(numberAffected);
if(!err){
return console.log('removed job id');
} else {
return console.log(err);
}
});
console.log('Job removed');
return res.send('');
} else{
console.log(err);
}
});
});
});
numberAffected is always 0 and 'removed job id' always get fired
You've got things backwards in your $pull. Try this instead:
CustomerModel.update({_id: job.customer}, {$pull : {jobs : job._id}}, ...
Related
I have the following mongoose schemas:
The main one is userSchema which contains an array of friends,
friendSchema. Each friendSchema is an object that contains an array of messageSchema. The messageSchema is the deepest object, containing the body of the message.
var messageSchema = new mongoose.Schema({
...
body: String
});
var conversationsSchema = new mongoose.Schema({
...
messages: [messageSchema]
});
var friendSchema = new mongoose.Schema({
user: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User',
},
conversation: {
type: mongoose.Schema.Types.ObjectId,
ref: 'Conversation',
},
}, { _id : false });
var userSchema = new mongoose.Schema({
...
friends: [friendSchema]
});
When retrieving specific user's friend, I populate its friends profiles, and if a conversation exist, I populate the conversation too.
How can I slice conversations.messages array, which resides in the population of the conversationobject ? I don't want to return the whole messages.
var userId = req.userid;
var populateQuery = [{ path:'friends.user',
select: queries.overviewConversationFields },
{ path:'friends.conversation' }];
User
.find({ _id: userId }, { friends: 1 })
.populate(populateQuery)
.exec(function(err, result){
if (err) { next(err); }
console.log(result);
}
EDIT(1) : I tried
.slice('friends.conversation.messages', -3)
EDIT(2) : I tried in populate query
{ path:'friends.conversation', options: { 'friends.conversation.messages': { $slice: -2 } }
EDIT(3) : For now, I can achieve what I want, slicing the array after the query is executed. This isn't optimized at all.
A little workaround that works.
I didn't found how to $slice an array that resides in a populated field.
However, the $slice operator works perfecly on any array, as long as its parent document has'nt been populated.
1) I decided to update the conversationSchema by adding an array containing both user's Id involved in the conversation :
var conversationsSchema = new mongoose.Schema({
users: [type: mongoose.Schema.Types.ObjectId],
messages: [messageSchema]
});
2) Then, I can easily find every conversation my user participates to.
As I said, I can properly slice the messages array, because nothing has to be populated.
Conversation.find({ users: userId },
{ 'messages': { $slice: -1 }}, function(err, conversation) {
});
3) Finally all I have to do, is to query all friends and conversations separately, and put back everything together, with a simple loop and a _find.
That would do more or less the same procedure of a Mongo population
Using async.parallel for more efficiency :
async.parallel({
friends: function(done){
User
.find({ _id: userId }, { friends: 1 })
.populate(populateQuery)
.exec(function(err, result){
if (err) { return done(err);}
done(null, result[0].friends);
});
},
conversations: function(done){
Conversation.find({ users: userId }, { 'messages': { $slice: -1 }}, function(err, conversation) {
if (err) { return done(err); }
done(null, conversation)
});
}}, function(err, results) {
if (err) { return next(err); }
var friends = results.friends;
var conversations = results.conversations;
for (var i = 0; i < friends.length; i++) {
if (friends[i].conversation) {
friends[i].conversation = _.find(conversations, function(conv){
return conv._id.equals(new ObjectId(friends[i].conversation));
});
}
}
});
// Friends contains now every conversation, with the last sent message.
i had this problem in my own code. i copied the code from the example at Mongoose Query Population to see what am i doing wrong. but i have the same problem with their code too.
the problem is about the log in the exec callback:
console.log('The creator is %s', story._creator.name);
^
TypeError: Cannot read property '_creator' of null
and here is the code.
var mongoose = require('mongoose'),
Schema = mongoose.Schema
var personSchema = Schema({
_id : Number,
name : String,
age : Number,
stories : [{ type: Schema.Types.ObjectId, ref: 'Story' }]
});
var storySchema = Schema({
_creator : { type: Number, ref: 'Person' },
title : String,
fans : [{ type: Number, ref: 'Person' }]
});
var Story = mongoose.model('Story', storySchema);
var Person = mongoose.model('Person', personSchema);
now using the models, making a new Person and saving it. and also saving a story and making the _creator of it to be equal to the id of the Person model, called aaron
var aaron = new Person({ _id: 0, name: 'Aaron', age: 100 });
aaron.save(function (err) {
if (err) return handleError(err);
var story1 = new Story({
title: "Once upon a timex.",
_creator: aaron._id // assign the _id from the person
});
story1.save(function (err) {
if (err) return handleError(err);
// thats it!
});
});
Story
.findOne({ title: 'Once upon a timex.' })
.populate('_creator')
.exec(function (err, story) {
if (err) return handleError(err);
console.log('The creator is %s', story._creator.name);
// prints "The creator is Aaron"
});
UPDATE:
in database i have only one collection called poeple with only one document:
{
"_id": 0,
"name": "Aaron",
"age": 100,
"stories": [],
"__v": 0
}
the code does not have the world people in it so where the collection name comes from? i'm confused.
thanks for any help you are able to provide.
The story1 is saved until the callback function of it is called. Please try to move the Stroy.find into the callback function of story1.save as below.
story1.save(function (err) {
if (err) return handleError(err);
Story
.findOne({ title: 'Once upon a timex.' })
.populate('_creator')
.exec(function (err, story) {
if (err) return handleError(err);
console.log('The creator is %s', story._creator.name);
// prints "The creator is Aaron"
});
});
I need to mention that I am totally aware of the fact that MongoDB is not a relational database in the first place. However it supports referencing other documents, hence some functionality should be supported, imo. Anyways, I have this relationship: a Company has many Departments and one Department belongs to one Company.
company.js
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var CompanySchema = new Schema({
name: {
type: String,
unique: true,
required: true
},
departments: [{
type: Schema.Types.ObjectId,
ref: 'Department'
}],
dateCreated: {
type: Date,
default: Date.now
},
dateUpdated: {
type: Date,
default: Date.now
}
});
module.exports = mongoose.model('Company', CompanySchema);
department.js
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var DepartmentSchema = new Schema({
name: {
type: String,
required: true
},
company: {
type: Schema.Types.ObjectId,
ref: 'Company'
},
dateCreated: {
type: Date,
default: Date.now
},
dateUpdated: {
type: Date,
default: Date.now
}
});
module.exports = mongoose.model('Department', DepartmentSchema);
Now, I am writing Node.js logic to manipulate this data using API. I get that if I create a new Department, I should add a reference to Company and I should create its reference in this Company's departments array. Simple. But what if a user changes the Company property of a Department? Say, the HR Department used to belong to Company A, but a user now moves it to Company B? We need to remove the reference to this department from Company A's array and push it to Company B. The same is when we want to delete a department. We need to find a company it belongs to and dis-associate it. My solution is working ATM, but seems rather clumsy.
routes.js
var Department = require('../../models/department'),
Company = require('../../models/company');
module.exports = function(express) {
var router = express.Router();
router.route('/')
.get(function(req, res) {
// ...
})
.post(function(req, res) {
// ...
});
router.route('/:id')
.get(function(req, res) {
// ...
})
.put(function(req, res) {
// First we need to find the department with the request parameter id
Department.findOne({ _id: req.params.id }, function(err, data) {
if (err) return res.send(err);
var department = data;
// department.name = req.body.name || department.name; Not relevant
// If the company to which the department belongs is changed
if (department.company != req.body.company._id) {
// We should find the previous company
Company.findOne({ _id: department.company }, function(err, data) {
if (err) return res.send(err);
var company = data;
// Loop through its departments
for (var i = 0; i < company.departments.length; i++) {
if (company.departments[i].equals(department._id)) {
// And splice this array to remove the outdated reference
company.departments.splice(i, 1);
break;
}
}
company.save(function(err) {
if (err) return res.send(err);
});
});
// Now we find this new company which now holds the department in question
// and add our department as a reference
Company.findOne({ _id: req.body.company._id }, function(err, data) {
if (err) return res.send(err);
var company = data;
company.departments.push(department._id);
company.save(function(err) {
if (err) return res.send(err);
});
});
}
// department.company = req.body.company._id || department.company; Not relevant
// department.dateUpdated = undefined; Not relevant
// And finally save the department
department.save(function(err) {
if (err) return res.send(err);
return res.json({ success: true, message: 'Department updated successfully.' });
});
});
})
.delete(function(req, res) {
// Since we only have id of the department being deleted, we need to find it first
Department.findOne({ _id: req.params.id}, function(err, data) {
if (err) return res.send(err);
var department = data;
// Now we know the company it belongs to and should dis-associate them
// by removing the company's reference to this department
Company.findOne({ _id: department.company }, function(err, data) {
if (err) return res.send(err);
var company = data;
// Again we loop through the company's departments array to remove the ref
for (var i = 0; i < company.departments.length; i++) {
if (company.departments[i].equals(department._id)) {
company.departments.splice(i, 1);
break;
}
}
company.save(function(err) {
if (err) return res.send(err);
});
// I guess it should be synchronously AFTER everything is done,
// since if it is done in parallel with Department.findOne(..)
// piece, the remove part can happen BEFORE the dep is found
Department.remove({ _id: req.params.id }, function(err, data) {
if (err) return res.send(err);
return res.json({ success: true, message: 'Department deleted successfully.' });
});
});
});
});
return router;
};
Is there any elegant solution to this case or it is just as it should be?
I see you have not yet captured the essence of the async nature of node.js ... for example you have a comment prior to department.save which says : and finally ... well the earlier logic may very will be still executing at that time ... also I strongly suggest you avoid your callback approach and learn how to do this using promises
I am trying to return an updated object as JSON, where the update was to set an array of objectIDs. I want the returned objected to have that array populated. For example, I have the following (simplified) model:
var UserSchema = new mongoose.Schema({
username: {type: String, unique: true, required: true},
friends: [{type: mongoose.Schema.Types.ObjectId, ref: 'User'}]
});
In my controller, I have:
exports.saveFriends = function(req, res) {
User.findById(req.params.user_id, function(err, user) {
// req.body.friends is JSON list of objectIDs for other users
user.friends = req.body.friends
user.save(function(err) {
user.populate({path: 'friends'}, function(err, ticket) {
if (err) {
res.send(err);
} else {
res.json(user);
}
});
});
});
}
This does in fact save the array properly as ObjectIDs, but the response user always shows "[]" as the array of friends.
Anyone see my issue?
My schema is as below
Sectionschema
var SectionSchema = new Schema({
name: String,
documents : {
type : [{
type: Schema.ObjectId,
ref: 'Document'
}]
}
}
}
DocumentSchema
var DocumentSchema = new Schema({
name: String,
extension: String,
access: String, //private,public
folderName : String,
bucketName : String,
desc: String
});
Api.js
exports.section = function(req, res, next, id) {
var fieldSelection = {
_id: 1,
name: 1,
documents : 1
};
var populateArray = [];
populateArray.push('documents');
Section.findOne({
_id: id
}, fieldSelection)
.populate(populateArray)
.exec(function(err, section) {
if (err) return next(err);
if (!section) return next(new Error('Failed to load Section ' + id));
// Found the section!! Set it in request context.
req.section = section;
next();
});
}
If I go this way, I have
the 'documents' object is []. However if I remove, "populateArray.push('documents');" then I get documents:['5adfsadf525sdfsdfsdfssdfsd'] -- some object Id (atleast)
Please let me know the way I need to populate.
Thanks.
Change your query to
Section.findOne({
_id: id
}, fieldSelection)
.populate('documents.type')
.exec(function(err, section) {
if (err) return next(err);
if (!section) return next(new Error('Failed to load Section ' + id));
// Found the section!! Set it in request context.
req.section = section;
next();
});
and this works. You need to give the path to populate.
If you just want "documents" in your schema pointing to Array of ObjectID which you will populate later. then you can use this.
var SectionSchema = new Schema({
name: String,
documents : [{
type: Schema.ObjectId,
ref: 'Document'
}]
});
And use the following to populate it
Section.findOne({
_id: id
}, fieldSelection)
.populate('documents')
.exec(function(err, section) {
if (err) return next(err);
if (!section) return next(new Error('Failed to load Section ' + id));
// Found the section!! Set it in request context.
req.section = section;
next();
});