I have a problem with a mongoose population and I don't know what I should do.
I got two schemas:
var userSchema = new userSchema({
username: { type: String, required: true, unique: true },
password: { type: String, required: true },
mods: [{ type: mongoose.Schema.Types.ObjectId, ref: 'users'}]
});
var dataSchema = mongoose.Schema({
title: { type: String, required: true, unique: true },
description: { type: String, required: true },
owner: {type: mongoose.Schema.Types.ObjectId, required: true}
});
So one user can have several data packages.
Some users are moderated by other users.
Whats the query for a moderator, that all his own data packages and the ones of the users he is moderating are listed?
You see that I have a SQL background and there's definitely another way to do it with MongoDB.
Thanks for your help!
I'm not clear understand what queries do you need but first you need set ref property in 'owner' field in dataSchema. As about population it's look like this:
//if you use callback
users.find({/*your query*/}).populate('mods')
.exec((err, result)=>{/*your code*/});
//if you use promise
users.find({/*your query*/}).populate('mods').exec()
.then(result=>{/*your code*/})
.catch(err=>{throw err});
Related
I have 2 models named "posts" and "status" and want to implement likes in them. first of all, I want the like to be able to record data like timestamps and other stuff depending on how it grows, which is why I made "like" be a model of its own.
The issue is since "posts" and "status" two models of their own are going to have "like" functionality.
Is there a way I could reuse the "like" model, instead of creating a separate "like" model for "posts" and "status", or how would you personally implement something like this?
Below is the post model
const postSchema = new mongoose.Schema({
title: {
type: String,
required: true,
trim: true
},
description: {
type: String,
required: true,
trim: true
},
owner: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'User'
}
}, {
timestamps: true
})
below is the status model
const statusSchema = new mongoose.Schema({
Body: {
type: String,
required: true,
trim: true
},
owner: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'User'
},
tags: [{
type: mongoose.Schema.Types.ObjectId,
required: True,
ref: 'User'
}]
}, {
timestamps: true
})
here is the like model which I would like users to be able to like both posts by users and statuses, while still able to retain information like the time it was liked and other information depending on the growth and need
const likeSchema = new mongoose.Schema({
user: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'User'
},
likedObject: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'Posts'
}
}, {
timestamps: true
})
Is there a way I could reuse the "like" model, instead of creating a separate "like" model for "posts" and "status" to capture the users and the time that they liked other user's statuses and posts?
Making Like Model was over complicating the entire thing so you could have something like this in your postSchema.
const postSchema = new mongoose.Schema({
title: {
type: String,
required: true,
trim: true
},
description: {
type: String,
required: true,
trim: true
},
owner: {
type: mongoose.Schema.Types.ObjectId,
required: true,
ref: 'User'
},
timeStamps:true,
//Adding the like property in each post but setting it to a default of 0
likes:{type:Number, default:0}
})
Now the key is identifying the post when like button is smashed
So what you could do on the client side is making sure that when like button is clicked you have an ID of the post to the function that your calling and, then pass that ID back to the server and you can have a logic like this below on your server and you would be able to add like functionality..
Server logic for adding like functionality
router.post("/api/likes/:id", async (request, response) => {
const post_id = request.params.id;
const post = await postModel.findOne({ _id: post_id });
post.likes += 1;
const updateDocument = await postModel.findOneAndUpdate(
{ _id: post_id },
post,
{
new: true,
}
);
return response.status(201).json({ msg: "Liked post" });
});
So the idea is two always be updating that specific document
I started learning some NodeJS, and how to make a REST API from Academind on YouTube, and learned what a relational and non-relational database is, etc.
With MongoDB, writes are rather cheap, so I want to minimize the number of reads that I do. At the moment I am trying to see how I could make an API, that will be for an app that's similar to discord's, although it'll be for fun.
Is this the right way to make a Schema?
const mongoose = require('mongoose')
const userSchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true, unique: true},
email: { type: String, required: true },
password: { type: String, required: true }, // TODO: Hashing, etc
guilds: [{
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true},
channels: [{
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true},
// Only the X most recent messages
messages: [{
_id: mongoose.Schema.Types.ObjectId,
message: {type: String, required: true},
user: {
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
}
}]
}],
// Only an X amount of users
users: [{
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
}]
}]
})
module.exports = mongoose.model('User', userSchema)
And then for the Guilds,
const mongoose = require('mongoose')
const guildSchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true},
channels: [{
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true},
// Only an X amount of messages
messages: [{
_id: mongoose.Schema.Types.ObjectId,
message: {type: String, required: true},
user: {
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
}
}]
}],
// All the users
users: [{
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
}]
})
module.exports = mongoose.model('Guild', guildSchema)
Channel Schema
const mongoose = require('mongoose')
const channelSchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true },
guild: {
_id: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true },
channels: [{
_id: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true }
}],
// The users of the guild, or just the channel?
// Could add a users object outisde of the guild object
users: [{
_id: mongoose.Schema.Types.ObjectId,
name: { type: String, required: true }
}]
}
})
module.exports = mongoose.model('Channel', channelSchema)
And finally for the messages
const mongoose = require('mongoose')
const messageSchema = mongoose.Schema({
_id: mongoose.Schema.Types.ObjectId,
user: {
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
},
message: {type: String, required: true},
channel: {
guild: {
_id: mongoose.Schema.Types.ObjectId,
name: {type: String, required: true}
// Store more data for each message?
}
}
})
module.exports = mongoose.model('Message', messageSchema)
I am not sure if this is how a non-relational schema should look like. If it's not, how would I go about to store the data that I need?
Also, let's say that I POST a message on channel X on guild Y with the users A B and C, how would I go about to update all the entries, to add a message?
I've only used the User.find({_id: id}).exec().then().catch() so far, so I am not sure how to go about to update them.
Thanks in advance!
The messages collection should be on its own, do not embed it into any collection. This is not a good idea to embed data that will grow without limit.
The idea to store the last 5 messages into other collection looks painful to implement.
Embed denormalised data from all collections into the users collection seems like a problem when you will have to update guilds, channels, guilds users.
You may embed channels into guilds. Channels would not grow without a limit, should be a reasonable amount, less than 100 of channels per guild and probably it always used with a guild that they belong to. If not, consider not to embed channels into guilds.
The power of mongodb is to build the schema that reflects how your app is using data. I would recommend starting with normalized data. And when problems with creating, reading, updating, deleting data will occur then make appropriate changes in your mongoose schema to solve the problem. Premature optimization will only hurts in the long run.
As always an answer depends on details. Since I do not know all details I would recommend three part article by William Zola, Lead Technical Support Engineer at MongoDB. part 1 part 2 part 3
I am developing an app like Tinder to experiment with MongoDB.
I am wondering about the database schema.
The main idea is that a user can "like" many users but no matter how much the number of "liked" profiles grows, it is very unlikely to hit the 16MB document size ceiling, so in my design, "liked" profiles are embedded inside one's profile.
below is a sample of my users schema using mongoose
var UserSchema = mongoose.Schema({
fullName: {
type: String,
trim: true
},
phone: {
type: String,
trim: true,
required: true,
},
gender: {
type: String,
enum: ['male', 'female'],
},
age: {
type: Number,
required: true
},
favorites: []
});
On the other hand, a user might be "disliked" by my many users.
So a user should not see on his next profile search the profiles of users who "disliked" him, so in my design I created a collection that holds the ID of the user who "disliked" and the ID of the user being "disliked".
below is a sample of my blocked schema using mongoose
var BlockedSchema = mongoose.Schema({
BlockerUserId: {
type: String,
required: true
},
BlockedUserId: {
type: String,
required: true
}
});
Do you think this is a good approach? and which indexes needs to be created?
Best,
You can manage dislike in the user collection only, you don't need a new collection.
var UserSchema = mongoose.Schema({
fullName: {
type: String,
trim: true
},
phone: {
type: String,
trim: true,
required: true,
},
gender: {
type: String,
enum: ['male', 'female'],
},
age: {
type: Number,
required: true
},
favorites: [],
dislike[]
});
and search like
var current_user_id = userdata._id;
db.users.find({dislike:{$ne:current_user_id}})
The above code is not syntactically correct but it will give you an idea.
Im using MongoDb, and I have a workspace schema with mongoose (v4.0.1):
var Workspace = new mongoose.Schema({
name: {
type: String,
required: true
},
userId: {
type: String,
required: true
},
createdOn: {
type: Date,
"default": Date.now
}
});
And a user schema:
var User = new mongoose.Schema({
email: {
type: String,
required: true,
unique: true
},
organisation: {
type: String,
required: true
},
location: {
type: String,
required: true
},
verifyString: {
type: String
},
verified: {
type: Boolean,
default: false
},
password: {
type: String,
required: true
},
createdOn: {
type: Date,
"default": Date.now
},
isAdmin: {
type: Boolean,
default: false
}
});
So the Workspace userId is the ObjectID from the User document.
When Im logged in as an adminstrator, I want to get all workspaces, as well as the email of the user that owns the workspace.
What Im doing is getting very messy:
Workspace.find({}).exec.then(function(workspaceObects){
var userPromise = workspaceObects.map(function(workspaceObect){
// get the user model with workspaceObect.userId here
});
// somehow combine workspaceObjects and users
});
The above doesnt work and gets extremely messy. Basically I have to loop through the workspaceObjects and go retrieve the user object from the workspace userId. But because its all promises and it becomes very complex and easy to make a mistake.
Is there a much simpler way to do this? In SQL it would require one simple join. Is my schema wrong? Can I get all workspaces and their user owners email in one Mongoose query?
var Workspace = new mongoose.Schema({
userId: {
type: String,
required: true,
ref: 'User' //add this to your schema
}
});
Workspace.find().populate('userId').exec( (err, res) => {
//you will have res with all user fields
});
http://mongoosejs.com/docs/populate.html
Mongo don't have joins but mongoose provides a very powerfull tool to help you with you have to change the model a little bit and use populate:
Mongoose population
You have to make a few changes to your models and get the info of the user model inside your workspace model.
Hope it helps
I Have schema design as below. I have posts array which is reference to the post model. Is it good idea to put it in User schema or should I not include as it is always growing as users add their post. I guess I should only put accesstokens in reference and not posts. Am I thinking right?
var UserSchema = new Schema({
username: {
type: String,
unique: true,
required: true,
lowercase: true,
trim: true
},
encrypted_password: {
type: String,
required: true
},
salt: {
type: String,
required: true
},
email: {
type: String,
unique: true,
required: true,
lowercase: true,
trim: true
},
mobile: {
type: Number,
unique: true
},
bio: {
type: String
},
created: {
type: Date,
default: Date.now
},
access_tokens: [{type: Schema.Types.ObjectId, ref: 'AccessToken'}],
posts: [{type: Schema.Types.ObjectId, ref: 'Post'}]
}, { collection: 'users' });
You should have a separate collection for Posts but you should keep the access_tokens within the user schema. One good reason you might consider separating the posts into its own collection is there are many use cases where you will query for just posts. However, with access_tokens, they will always be tied to a user.
tldr;
Posts should have their own schema
Access tokens should be in user schema
Hope that helps!