How to write multi ref for one property of one mongoose schema, like this(but wrong):
var Schema = mongoose.Schema;
var PeopleSchema = new Schema({
peopleType:{
type: Schema.Types.ObjectId,
ref: ['A', 'B'] /*or 'A, B'*/
}
})
You should add string field to your model and store external model name in it, and refPath property - Mongoose Dynamic References
var Schema = mongoose.Schema;
var PeopleSchema = new Schema({
externalModelType:{
type: String
},
peopleType:{
type: Schema.Types.ObjectId,
refPath: 'externalModelType'
}
})
Now Mongoose will populate peopleType with object from corresponding model.
In the current version of Mongoose i still don't see that multi ref possible with syntax like you want. But you can use part of method "Populating across Databases" described here. We just need to move population logic to explicitly variant of population method:
var PeopleSchema = new Schema({
peopleType:{
//Just ObjectId here, without ref
type: mongoose.Schema.Types.ObjectId, required: true,
},
modelNameOfThePeopleType:{
type: mongoose.Schema.Types.String, required: true
}
})
//And after that
var People = mongoose.model('People', PeopleSchema);
People.findById(_id)
.then(function(person) {
return person.populate({ path: 'peopleType',
model: person.modelNameOfThePeopleType });
})
.then(populatedPerson) {
//Here peopleType populated
}
...
Related
I am using mongodb with mongoose. And i am wondering if it is possible to have multiple references for an object id attribute in a schema.
I have tried the code underneath and it did not work.
const Schema = new Schema({
refrens: {
type: ObjectId,
// this did not work
ref: [
"Post",
"Account"
],
required: true
}
});
I know it is possible to remove the ref attribute (field, key) and then all object ids are valid but i want certain object ids to be valid, the object ids of the Post and Account model.
const Schema = new Schema({
refrens: {
// This will allow all different types of object ids to be the value
type: ObjectId,
required: true
}
});
Look like refPath is what you need. You can do something like this:
const Schema = new Schema({
refrens: {
type: ObjectId,
refPath: 'onModel',
required: true
},
onModel: {
type: String,
required: true,
enum: ['Post', 'Account']
}
});
I am new to mongoose and I was strugling whole day trying to understand populate. I managed to do simple examples but now I created two schemas:
First which is UserSchema with some user details:
const UserSchema: mongoose.Schema = new mongoose.Schema ({
name: String,
email: String
});
And second which is MatchSchema witch I want to be populated with user details but I am not sure if something like this will work:
const MatchSchema: mongoose.Schema = new mongoose.Schema ({
player_one: {
id: String,
score: Number,
player_details: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User'
}
},
player_two: {
id: String,
score: Number,
player_details: {
type: mongoose.Schema.Types.ObjectId,
ref: 'User'
}
},
winner: String
},{timestamps: true});
Probably I used something which wont work and any help will be appriciated.
You need to create a Mongoose model using the UserSchema and name it 'User'. You can then create a Match model using the MatchSchema. Assuming the UserSchema and MatchSchema are in the same file, you can add the following:
const User = mongoose.model('User', UserSchema)
const Match = mongoose.model('Match', MatchSchema)
Then when you want to populate the Match model with User data:
let data = Match.find({})
.populate('player_one.player_details')
.populate('player_two.player_details')
If I have a model Attachment, which can be divided into 4 types: Link, YoutubeVideo, GoogleDriveFile, and GoogleDriveFolder, how can I use Mongoose to discriminate Attachment into these types, and allow them to be subdocuments in another schema; Post?
I've created the base Attachment model, and divided it into separate models using discriminators:
var AttachmentSchema = new Schema({
id: {type: String, required: true},
title: {type: String, required: true}
});
var Attachment = mongoose.model('Material', AttachmentSchema);
module.exports = {
DriveFile: Attachment.discriminator('GoogleDriveFile', new mongoose.Schema()),
DriveFolder: Attachment.discriminator('GoogleDriveFolder', new mongoose.Schema()),
Link: Attachment.discriminator('Link', new mongoose.Schema()),
YoutubeVideo: Attachment.discriminator('YoutubeVideo', new mongoose.Schema())
};
Now, in the Post schema, there should be an array of attachments, with varying types:
var Attachment = require('./attachment');
var PostSchema = new Schema(
text:{type: String},
attachments: [Material] // Could be Material.Link, Material.YoutubeVideo, etc
});
When I do this, I get an error saying "Undefined type Model at GoogleDriveFile. Did you try nesting Schemas? You can only nest using refs or arrays."
I don't know what this error means, and I can't find any docs explaining how to do this. Help?
Try doing the following:
var AttachmentSchema = new Schema({
id: {type: String, required: true},
title: {type: String, required: true}
});
var PostSchema = new Schema({
text: { type: String },
attachments: [ AttachmentSchema ] // Could be Material.Link, Material.YoutubeVideo, etc
});
var attachmentArray = PostSchema.path('attachments');
module.exports = {
Post: mongoose.model('Post', PostSchema),
DriveFile: attachmentArray.discriminator('GoogleDriveFile', new mongoose.Schema({})),
DriveFolder: attachmentArray.discriminator('GoogleDriveFolder', new mongoose.Schema({})),
Link: attachmentArray.discriminator('Link', new mongoose.Schema({})),
YoutubeVideo: attachmentArray.discriminator('YoutubeVideo', new mongoose.Schema({}))
};
The key is to NOT use a mongoose Model use the schema.path of the parent document schema as the base for your discriminators.
search for the term docArray on this link: Mongoose Discriminator documentation
so I've been at it for like 4 hours, read the documentation several times, and still couldn't figure out my problem. I'm trying to do a simple populate() to my model.
I have a User model and Store model. The User has a favoriteStores array which contains the _id of stores. What I'm looking for is that this array will be populated with the Store details.
user.model
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var UserSchema = new Schema({
username: String,
name: {first: String, last: String},
favoriteStores: [{type: Schema.Types.ObjectId, ref: 'Store'}],
modifiedOn: {type: Date, default: Date.now},
createdOn: Date,
lastLogin: Date
});
UserSchema.statics.getFavoriteStores = function (userId, callback) {
this
.findById(userId)
.populate('favoriteStores')
.exec(function (err, stores) {
callback(err, stores);
});
}
And another file:
store.model
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var StoreSchema = new Schema({
name: String,
route: String,
tagline: String,
logo: String
});
module.exports = mongoose.model('Store', StoreSchema);
After running this what I get is:
{
"_id": "556dc40b44f14c0c252c5604",
"username": "adiv.rulez",
"__v": 0,
"modifiedOn": "2015-06-02T14:56:11.074Z",
"favoriteStores": [],
"name": {
"first": "Adiv",
"last": "Ohayon"
}
}
The favoriteStores is empty, even though when I just do a get of the stores without the populate it does display the _id of the store.
Any help is greatly appreciated! Thanks ;)
UPDATE
After using the deepPopulate plugin it magically fixed it. I guess the problem was with the nesting of the userSchema. Still not sure what the problem was exactly, but at least it's fixed.
I think this issue happens when schemas are defined across multiple files. To solve this, try call populate this way:
.populate({path: 'favoriteStores', model: 'Store'})
I was wondering if it's possible in Mongoose to have a subdocument based on another document.
Normally I would do something like this:
'use strict';
var mongoose = require('mongoose'),
Schema = mongoose.Schema;
var CountrySchema = new Schema({
name: String,
info: String,
cities : [
{
type: Schema.ObjectId,
ref: 'Ressource'
}
]
});
module.exports = mongoose.model('Country', CountrySchema);
this however create a new document and then references it via the id to the country document. This is not what I want, I want the resource document to be nested inside the country document. How would I do this?
I found that this fixed my problem:
'use strict';
var mongoose = require('mongoose'),
Schema = mongoose.Schema,
ressourceSchema = require('../ressource/ressource.model');
var CountrySchema = new Schema({
name: String,
info: String,
cities : [
ressourceSchema.schema
]
});
module.exports = mongoose.model('Country', CountrySchema);