Reference to component - node.js

Question

Using knockout.js in node, how can I get a reference to a child VM component, which was invoked from a template?
Illustration
I have a Question Model, VM, containining a custom Resource component, with it's respective Model and VM. The Resource VM registers a custom component and receives a Resource Model object as a parameter, which was constructed by the parent Question Model. This constructed resource is passed as a parameter with the template:
QuestionModel.js
this = new QuestionModel(...);
this.resource = new ResourceModel(some data);
question-template.html
<div data-bind="foreach: { data: questions, as: 'question' }">
<!-- question related -->
<resource params="resource: question.resource"></resource>
</div>
ResourceVM.js
define(function(require, exports, module) {
var ko = require('knockout');
var ResourceViewModel = function ResourceViewModel(params) {
this.resource = params.resource;
this.somethingSpecific = function() {
return 'some value manipulate from this model';
}
}
ko.components.register('resource', {
viewModel: {
createViewModel: function(params, componentInfo) {
return new ResourceViewModel(params);
}
},
template: {
require: 'text!/resource-template.html'
}
});
return ResourceViewModel;
});
I want to be able to call functions of the Resource VM (like question.resourceVM.somethingSpecific()).
What is a proper way of getting a reference to a component child?
The only solution I can think of is to pass the parent object with the parameters and extend it from child, which is obviously bad.

Answer 1

Your QuestionModel already has access to this.resource, so the way forward might be by doing it through the data models, instead of through the view models. Having somethingSpecific() as an attribute on either QuestionModel or ResourceModel instead of ResourceViewModel would solve the problem nicely.
I would argue that manipulating data is the responsibility of the entity that holds it; the job of the ResourceViewModel is only to provide glue between the data model and the DOM.
var QuestionModel = function QuestionModel() {
this.somethingSpecific = function somethingSpecific() {
this.resource.doStuff();
};
};
this = new QuestionModel();
this.resource = new ResourceModel(some data);
You could then give your resource component access to the question instead of the child resource:
var ResourceViewModel = function ResourceViewModel(params) {
this.question = params.question;
this.resource = this.question.resource;
}