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javascript mongoose dynamic model assignment

Ive looked related posts and couldn't quite find what I was looking for.
So I am build a backend rest api and I have certain tests I am collecting data on. The tests have their own models, and these models are associated with collections (obviously).
So I have a separate controller for each model. Now I have a "job" controller which queries data from each separate test. Now I have a separate script where I store these model objects in an JSON object. I am wondering how I can access these models properly (I am close but cant quite assign properly). Here is the block:
const testMappings = {
'aprobe':aprobe,
'status':status,
//'rxserial':rxserial,
}
Now when I try assignment as follows, where testMappings is the imported script variable:
const testMappings = activeTests.testMappings;
console.log(testMappings['aprobe']);
I get the following output:
Model {aprobe}
I would like to access the actual aprobe object. Also if anyone knows a better way of dynamically assigning these (instead of having bunch of if statements ie if(name == 'aprobe').... do something), it would be much appreciated.

You are probably looking for something like below :
const name = 'aprobe';
Object.keys(testMappings).indexOf(name) > -1 ? testMappings[name] : null
the above should give you: Model {aprobe}
So basically if the key exists in your object then you'd like to fetch the value of that key which would give you your model dynamically.

then() returning a null value when it should be pending

Ember 2.17
I am calling an helper from my template :
{{#each invoice.invoiceLines as |line| }}
{{pricings/full-pricing line.pricing}}
{{/each}}
invoice,invoiceLine, as well as pricing are ember models.
Here is how invoice is created in model () :
model(params) {
let invoice= this.store.findRecord('invoice',params.invoice_id)
return Ember.RSVP.hash({
invoice: invoice,
allShares: invoice.then((i)=>{return i.allShares()}),
detailShares: invoice.then((i)=>{return i.detailShares()})
});
}
The goal of the helper is to take pricing, extract numbers (everything is in the model, no more relations) and return a string formatting the initial price and the subscription price.
The helper is as following :
import { helper } from '#ember/component/helper';
export function pricingsFullPricing([pricing]) {
return pricing.then(
p=>{
debugger
},p=>{
}
)
}
export default helper(pricingsFullPricing);
When I run the page, debugger is called twice (the template loop run once).
First time p is null, the second time it is a pricing.
Isn't then supposed to prevent that? Why does it behave like that?

Your route is wrong, routes are promise aware (that's what hash is for), it should be:
model(params) {
return Ember.RSVP.hash({
invoice: this.store.findRecord('invoice',params.invoice_id)
//allShares: invoice.then((i)=>{return i.allShares()}),
//detailShares: invoice.then((i)=>{return i.detailShares()})
});
}
Then your handlebars is just:
{{#each model.invoice.invoiceLines as |line| }}
{{line}}
{{/each}}
You also shouldn't call methods like you are on a model. It's not really clear what allShares(), etc does but these should (probably) be computed in the controller. Something along the lines of:
import { computed } from '#ember/object';
export default Controller.extend({
allShares:computed('model.invoice', function(){
return this.get('model.invoice').allShares();
});
});
Though this doesn't seem ideal. Like I said, it's hard to be explicit as it's not clear what your trying to do here. It'd probably make more sense if your extracted these methods into a service.
You then don't need the helper at all. This appears to be just trying to work around promises.
It makes life a lot easier if you try and load all server side data in the route before load.

First rule of helpers
Each time the input to a helper changes, the compute function will be called again.
Second, there's nothing about helpers that will make this block subsequent calls because you are returning a promise.
export function pricingsFullPricing([pricing]) {
return pricing.then(
p=>{
debugger
},p=>{
}
)
}
You've created a simple helper here that will use the promise itself as the value. Look at ember-promise-helpers/await to see how a class based helper is used to manually set the value that's displayed in the template.
Now, if you're wondering why the recomputation is happening, I'm going to have to speculate based off the knowledge I have of Ember data just from being part of the Ember community (I've never actually used Ember Data). You know line.pricing is a promise? I can then assume your using some sort of relationship, which will most likely have to be loaded via an ajax call (hence the promise). But these relationships in Ember data, iirc, use this PromiseProxyMixin that allow them to behave simultaneously like a promise or like an object (depending on whether the data is in the store already or not). This is what allows you to reference the promise in your template without then
See this article for a better understanding of what I mean

Private variables in Ember-data DS.Model

I want to store a private variable on each DS.Model. Its purpose is to store a pending callback (in case I want to cancel it).
I have tried this (and it works):
DS.Model.reopen({
init() {
let _pending; // my private var
this._getPending = () => _pending; // get private var
this._setPending = callback => _pending = callback; // set private var
this._super(...arguments);
}
});
I have placed this in an initializer, and it works as I expect it to.
My questions are: Is this a good practise? is it likely to mess anything up? ...and, is there a better way?
Personally, I'm happy with the way it works.. but I'm not sure if its the "Ember" way. This is going to go into an Ember-cli addon, so I would like it to be the most "best practise" as possible. (the _getPending/_setPending method are only to be used internally within the addon.)

Here are my 2 cents on this. I would say no it is not a good practice, but it should be okay since they are just Ember Objects. The question here is what is Ember data model used for? From doc it says:
"Models are objects that represent the underlying data that your application presents to the user."
By definition this is not what they are designed for, so just because you are able to it does not mean that you should use them like this.
Pending callback so it can be canceled? Ember model API has defined state objects that can be used for this purpose. http://emberjs.com/api/data/classes/DS.Model.html Flags like isDeleted, isValid, isNew...gives all possible state.
I would place them in router actions where they are easy tested with integration tests.
You can check this screencast that explains them:
https://www.emberscreencasts.com/posts/102-ember-data-20-model-states-and-flags
Hope it helps.

Load includes on existing model

I'm trying to load includes on an existing model in sequelize. In express we pre check the models to see if they exist in the middleware.
So once we're in the actual "controller" we want to run some includes on that existing model that is passed in.
req.models.item.incude([
{model: Post, as: 'posts'}
])
Is there any way to accomplish this?
EDIT:
I know we can do something like this.
return req.models.item.getThing()
.then(function (thing) {
req.models.item.thing = thing;
return req.models.item;
});
But:
My expansions for includes are a dynamic property that come via url parameters, so they are not know ahead of time.
It I return the above you will not see the "thing" in the response. I need it nicely built as part of the original instance.
Something like a .with('thing', 'other.thing'); notation would be nice. Or in the case of sequelize .with({include: ...}); or .include([{model: ...}]);

If the variable req.models.item is already an Instance but without its other related instances ("includes"), then you could include them using something like the following code:
Item.findAll({
where: req.models.item.where(),
include: [{
model: SomeAssociateModel,
}]
})
.then(function(itemWithAssoc) {
// itemWithAssoc is an Instance for the same DB record as item, but with its associations
});
See here for some documentation. See here for a script demo'ing this.
Update: Given the instance, how do I just get the associated models?
To do this just use the automatically generated "getAssociation" getter functions, e.g.:
function find_associations_of_instance(instance) {
return instance.getDetails();
}
I've updated the script to include this as an example. For more information on these functions, see the SequelizeJS docs.

understand Backbone set method and Model

All, I am a newbie of Backbone. and I am trying to understand the Model of Backone. Especially how to define a Model. so far, I didn't saw a clear or formal way about how to define a Model for backbone.
For example Let's see the set method in help doc .
set
model.set(attributes, [options])
Set a hash of attributes (one or many) on the model.
Say we have some code like below . I think set method actually is assign a javascript object to the Model.
window.Employee = Backbone.Model.extend({
validate:function(attrs){
for(var key in attrs){
if(attrs[key] == ''){
return key + "can not be null";
}
if(key == 'age' && isNaN(attrs.age)){
return "age is numeric";
}
}
}
});
....
var attr = {}; // I can't not sure what is {} mean.
$('#emp-form input,#emp-form select').each(function(){
var input = $(this);//using jquery select input and select. and enumerate all of them.
attr[input.attr('name')] = input.val();//I am not sure what does it means
});
if(employee.set(attr)){
Employees.create(employee);
}
....
in this example ,I didn't saw the classical way which we can see in java class or c# class to define the class fields or methods. but only see a validate function .Is there anybody who can tell me more about it to help me understand? thanks.

To define a model in Backbone you have to extend the Backbone.Model object. For example if you'll like to create a new User model you could write something like this:
var User = Backbone.Model.extend({})
You can also overwrite some model methods to fill your needs. For example you can change the urlRoot attribute to tell the model where should he fetch the data.
Backbone models contain your data in the attributes attribute. You change those attributes by using the model set method and you can read the value stored in the model using the get method. So if you had some inputs where a user can enter information, for example creating a new user with his name and email and you have a form with a text input for both of them. You could do domething like this:
var user = new User;
user.set('name', $('#name').val());
user.set('email', $('#email').val());
attributes = {
name: user.get('name'),
email: user.get('email')
};
user.save(attributes);
There are a lot of ways to re-factor this code to make it look better but it help to see how you could use those methods. You should check the Backbone documentation to explore how they work a little bit more. Hope this helps!
PD: In my example I set an attribute a time, but you could also send a hash of attributes to set more values in one call.

The model in JS is basically a wrapper for data, with CRUD and simple validation functions. To work properly you need to make server functions to work with (ajax), I think this tutorial says it all http://backbonetutorials.com/what-is-a-model/. Instead of database the model works with your application server side.
If you have custom actions (not just add/edit/remove) on your data, you can manually "set()" data, use "onchange" event and refresh your view when needed. You can even attach "onchange" events only on specific fields and make custom functions in your view to handle each special field (for validation or display).
You can define fields at initialize and defaults value, but not custom functions (ofc you can do model.customFuntion() but I don't recommend it.
In order to make it more "clasical way" you need to use the other Backbone functions http://backbonejs.org/#Collection-Underscore-Methods and Backbone.Collection.