I am trying to create an application for sports event management system using MEAN.io
Since it uses the modular approach, there are different packages that comes in skeleton application like system, users, access. What i want to do is make a new package called players and it should extend the users package. The players schema would contain extra fields section and teams.So how do I extend the User Schema of users package in players package?
You can make your players package be dependent on users.
Players.register(function(app, auth, users, database) {...});
You now have access to the database and can load the user schema with
var userModel = database.connection.model('User');
and you can use the schema.add function to extend the schema
userModel.schema.add({ scrore: 'string'});
This should add the score field to the user model
I think this might work for you. But I was told from a member of mongoose team that schema.add only works before compiling the model. See this link for more info about schema add http://mongoosejs.com/docs/api.html#schema_Schema-add
Related
I'm trying to implement some kind of permission framework in Node js, using sequelize as an ORM (with Postgres). After hours of research, the closest thing I can find to do this with existing npm modules is using acl with acl sequelize to support my stack.
The problem is that it looks like the acl module assigns a role, where that role would get a set of permissions to all instances of a specific resource. However, I need to do permissioning for instances based on existing relationships of that user.
As an example, consider a permissioning system for a simple forum. It gives these permissions for each role:
// allow guests to view posts
acl.allow("guest", "post", "view");
// allow registered users to view and create posts
acl.allow("registered users", "post", ["view", "create"]);
// allow administrators to perform any action on posts
acl.allow("administrator", "post", "*");
Suppose that I want to also add the ability for registered users to also edit their own posts, and the user has a relationship to all the posts they've created.
Is there any way for this module to do this, or any other module that can support this kind of behavior on the database / ORM level?
If not, and I have to implement a custom one, what would the best approach to creating something like this.
There is relatively new library CASL. I'm the author of this library. And it's possible to implement your usecase quite easily:
const { AbilityBuilder } = require('casl')
const ability = AbilityBuilder.define((can, cannot) => {
can('read', 'all')
can(['update', 'delete'], 'Article', { author_id: loggedInUser.id })
})
The code above basically says:
- anyone can read everything
- anyone can update and delete articles where author_id equals logged in user id
Later you can do:
ability.can('delete', 'Post')
//or
ability.can('update', post)
// where post variable is an instance of your Post model
Also there is an article which explains how to integrate CASL with MongoDB and Express exactly for your usecase.
I installed loopback-component-passport so I can use it with strongloop's Loopback framework. I followed the docs,
but after this command: npm install loopback-component-passport, the following files/models are not created:
UserIdentity model
UserCredential model
ApplicationCredential model
These files are used by Loopback for third-party authentication. Do I have to add them manually? Or am I doing something wrong?
Yes, you have to add them manually. You can refer this example, loopback-example-passport on github.
The reason is the relationships of loopback-component-passport's core models i.e UserIdentity model, UserCredential and ApplicationCredential with Loopback's core model AccessToken and User doesn't come preconfigured which is required for authentication.
Also, you might notice that the developer extended the models but didn't added any model.js. This is so because there was no need to add any runtime logic. For starters, you might want to extend the core models as per the example and create relationship and acls only. Then you can proceed with custom logic.
I think loopback built in models stay tucked away in node_modules, so assuming you mean that these tables are missing from your datastore, you can do an autoupdate in order to get loopback to build any missing tables.
I add the following code to a file in the server/boot directory when I need to during development.
module.exports = function(app, done) {
app.datasources.mysql_db.autoupdate(function(err) {
if (err) throw err;
console.log("autoupdate");
done();
})
}
Where mysql_db is the name of your datastore.
This will update the datasource when the server boot but shouldn't drop existing data (saying that I have seen instances where foreign keys are lost, so care & db backup is still needed).
Good Afternoon,
I am new with node.js and I try to develope an only command app.
For this app I need an ORM and I wish to use WATERLINE as standalone but not in express framework.
I looked at the example and I succeed to see my different collections.
// Our collections (i.e. models):
ontology.collections;
console.log(ontology.collections);
// Our connections (i.e. databases):
ontology.connections;
I am stucked after this. I can't find a way to return my models and make queries.
If someone could help me taht would be great.
Thanks
If you initialized Waterline in the ontology variable and got the collections successfully loaded as you say, now you can access each collection loaded (with loadCollection()) like this:
ontology.collection.mycollection
Where mycollection is the identity defined in your model.
Then you can make queries:
ontology.collection.mycollection.find(...)
Can anyone guide me on how to setup relational schema & performs joins in sails.js?
Associations are officially Supported in Waterline
Overview
From the docs:
With Sails and Waterline, you can associate models across multiple data stores. This means that even if your users live in PostgreSQL and their photos live in MongoDB, you can interact with the data as if they lived together in the same database. You can also have associations that span different connections (i.e. datastores/databases) using the same adapter. This comes in handy if, for example, your app needs to access/update legacy recipe data stored in a MySQL database in your company's data center, but also store/retrieve ingredient data from a brand new MySQL database in the cloud.
Supported Association Types
One to Many
Many to Many
Cross-adapter Dominance
One to One
One Way
Planned Association Types
Through Associations
Original Post
I'm the author of Waterline, the ORM used in Sails. Waterline is brand
new and we are adding features all the time. Currently we don't have
support for associations but it's next on the roadmap. We worked out
an API for associations that I think most people will really like. You
can view the work in progress and the proposed API at: [Proposed Sails
Associations API][1].
We are going to tackle Associations and Transactions next and hope to
have them ready in the next month or so.
In the mean time if you are using the MySQL or PostgreSQL adapters
they both expose a raw .query() method that allows you to pass in a
hand built sql query and have it executed. I totally realize this
isn't ideal but should allow you to continue building your app while
we get support for associations and joins.
The function signature for the query method is:
Model.query(<sql query>, <optional data>, callback);
The example from particle banana works but should actually use "new" like "var instance = new User._model(values)". I'm using the following code and it works.
Accounts.query(query, function(err, accounts) {
if (err)
return fn(err);
accounts = _.map(accounts, function(account) {
return new Accounts._model(account);
});
fn(null, accounts);
});
The most relevant question here on StackOverflow was this, which still doesn't answer my question because the answer nor the redis repo give a tutorial/walk-through that beginners don't understand.
The thing is, I have absolutely no idea how to setup a simple database in order to create a simple to-do list or blog on my own. This is probably the closest tutorial on how to setup a database. But it's lacking in a sense due to not having a schema or so defined in order for me to edit or add "tables".
Simply put, I'm looking for a tutorial a complete beginner is able to follow on how to setup a database and define custom schemas for data (e.g. products that can have reviews nested in them).
Any suggestions?
I guess this should cover it: Node.js, MongoDB and Mongoose
You mentioned that you wanted to create a Todo application. There is TodoMVC. You can see various MVC Frameworks in action. There's also an example with Mongoose and Backbone.
For installing different NoSQL options including MongoDB, CochDB, Redis and SQLite for use with Node.js this is a nice walk through.
Once installed the following steps are required to get going with the database. Typical example for mongodb:
var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/your_database');
var Schema = mongoose.Schema;
var User = new Schema({
'_id' : String,
'name' : String,
'votes' : Number });
var User_Model = mongoose.model('User', User);
Approaches to read/ write data from/to the database varies.
I think the simplest thing to do is to download and install MongoDB and use the mongodb-native driver to store and access your data.
MongoDB is schema-less so you won't need to define any table or keys in advance. Simply open a collection (which will be created automatically if it doesn't exist) and start storing documents/objects in it.
Mongo is fast, powerful and, in my opinion, easy to use.
See mongodb.org for more information.
I find this screencasts very helpful for nodeJS + MongoDB, even though the mongoose has been updated a lot since the video, but the basics remained. And you'll learn the new one in no time just by skimming mongoose's doc.
I've downloaded all of his videos and watch them every time I need brushing up my node skillz :p
Sidenote: He just uploaded screencast for couchDB, for other who prefers different cup of tea.