domodel

domodel is front-end library that organizes the user interface into models (look) and bindings (behavior) it follows the principle of separation of concerns, it also introduce elements of the observable pattern for the communication between the different parts of the user interface.

Getting started

Installing

Setup a new project

npx create-domodel-app [name]

Setup as a dependency to an existing project

npm install domodel

Model

A model is a JSON representation of a DOM Element.

Let's take this model for example:

export default {
  tagName: "button"
}

That would the equivalent of:

const button = document.createElement("button")

A model with children:

export default {
  tagName: "div",
  children: [
    {
      tagName: "h2",
      identifier: "headline",
      textContent: "Unveil a new world"
    }
  ]
}

Notice the textContent property. You can set any Element properties in this fashion.

The identifier property is a model property.

Note: The term model will later be used to refer to both the model and its Binding to make it simpler.

You can also ommit the tagName and you will get a fragment document model:

export default {
  children: [
    {
      tagName: "h2",
      identifier: "headline",
      textContent: "Unveil a new world"
    }
  ]
}

That would the equivalent of:

const documentFragment = document.createDocumentFragment()
const h2 = document.createElement("h2")
// ...
documentFragment.appendChild(h2)

Properties

Most properties listed in your model are defined at the Element level.

However custom properties are not set on the Element as they have unusual behaviors they are treated differently:

• tagName - String - Passed to createElement
• children - Array - To add children to an Element
• identifier - String - To save and retrieve a Node
• model - Model - Specify the model that should be ran
• binding - Binding - Specify the Binding to use when running the model (model property must be set)
• properties - Object - Specify the arguments to pass along the Binding (binding property must be set)

Core

Adding models to the DOM and managing them

To add a model to the DOM we use the Core.run method provided by the DOModel module and tell it how to add them.

Create a main.js in src/, it is the entry point module that is defined in your index.html :

src/main.js

import { Core } from "domodel" // first we're importing DOModel

// It is preferred to use camel case and suffix model names with "Model" and binding names with "Binding" such as: RectangleModel and RectangleBinding.
import Model from "./model/model.js" // the model we defined earlier, it is our super model
import ModelBinding from ".model/model.binding.js" // the binding we will be defining .bindinglater

window.addEventListener("load", function() { // we only add the
  Core.run(Model, {
    method: Core.METHOD.APPEND_CHILD, // This is the default method and will append the children to the given parentNode.
    binding: new ModelBinding({ myProp: "hello :)" }), // we're creating an instance of our binding (which extends the Binding class provided by DOModel) and passing it to the run method.
    parentNode: document.body // the node we want to target in this case it is the node where we want to append the child node using appendChild.
  })
})

The documentation for Core.run is available here.

The associated Binding:

src/model/model.binding.js

import { Core } from "domodel" // you could import the library again and run yet another model inside this model

class ModelBinding extends Binding {

  onCreated() {
    const { myProp } = this.properties

    console.log(myProp) // prints hello

    // access your model root element through the root property: this.root

    // access identifier with the identifier property:

    this.identifier.headline.textContent = "The new world was effectively unveiled before my very eyes"

    // you might even run another model inside this model
  }

}

export default ModelBinding 

Methods

• APPEND_CHILD Append your model to parentNode

• INSERT_BEFORE Insert your model before parentNode

• REPLACE_NODE Replace parentNode with your model

• WRAP_NODE Wrap parentNode inside your model

• PREPEND Insert your model before the first child of parentNode

They are available through Core.METHOD.

Binding

Binding are the behavior part of our model it is required for any model to have a Binding with it.

Hooks

The following are hooks that your binding can implement to add specific behaviors to your models.

onCreated

This method will be called before your model is added to the DOM.

onRendered

This method will be called immediately after your model is added to the DOM.

Properties

The following properties are made available from within the the instance of a Binding:

• properties Properties passed along when instancing a binding.
• root Root Element of your model.
• identifier Hosts individual Element previously tagged in the definition of the model (see Model properties).

Methods

listen

Listen to a given observable event. See Binding.listen.

This is the preferred method for listening to events as any listener will be cleaned up when your binding is removed using Binding.remove.

run

Synonym of Core.run, with the differences being :

• parentNode property is set to the current binding root element.
• All properties within Binding.properties are inherited by the child model.
• A hierarchy of models is created using Binding._children. Making it easier to remove them using Binding.remove.

remove

Remove the model from the DOM. See Binding.remove.

Observable

An Observable is a way for your models to communicate with each other.

src/object/observable-example.js

import { Observable } from "domodel"

class ExampleObservable extends Observable {

  // you can have a constructor

  // getter setter...

  // or even better, you could have methods.

}

export default ExampleObservable 

Listening to events

EventListener

Here we associate the EventListener with our current binding and give it properties.observable as the observable to register the events to.

src/model/model.binding.js

import { Observable, Binding } from "domodel"

import ModelEventListener from "/model/model.event.js"

class ModelBinding extends Binding {

  constructor(properties) {
    super(properties, new ModelEventListener(properties.observable))
  }

}

export default ModelBinding 

Any method inside an EventListener is automatically registered as a listener to the given observable.

src/model/model.event.js

import { EventListener } from "domodel"

class ModelEventListener extends EventListener {

  message(data) {
    console.log(data)
  } 

}

export default ModelEventListener 

observable.listen

Useful when you want to listen to other parts your UI.

src/model/model.binding.js

import { Observable, Binding } from "domodel"

class ModelBinding extends Binding {

  onCreated() {

    const observable = new Observable()

    observable.listen("message", data => {
      console.log(data)
    })

  }

}

export default ModelBinding 

Emitting events

src/model/model.binding.js

import { Observable } from "domodel"

class ModelBinding extends Binding {

  onCreated() {

    const observable = new Observable()

    observable.emit("message", { /* data go here */ })

  }

}

export default ModelBinding 

Running your model:

import { Core, Observable } from "domodel"

import Model from "/model/model.js"
import ModelBinding from "/model/model.binding.js"

const observable = new Observable()

Core.run(Model, { parentNode: document.body, binding: new ModelBinding({ observable }) })

Advanced

Nesting models

Method 1 - Import

src/model/application.js

import Model from "./model.js"

export default {
  tagName: "div",
  children: [
    Model
  ]
}

Method 2 - Binding

src/model/application.binding.js

import { Core } from "domodel"

import Model from "./model.js"
import ModelBinding from "./model.binding.js"

class extends Binding {

  onCreated() {
    Core.run(Model, { parentNode: this.root, binding: new ModelBinding() })
  }

}

export default class 

Method 3 - "model" property

src/model/application.js

import Model from "./model.js"
import ModelBinding from "./model.binding.js"

export default {
  tagName: "div",
  children: [
    {
      model: Model,
      binding: ModelBinding // optionnal
      properties: {} // optionnal
      identifier: "model" // optionnal
      // Any other property is not handled.
    }
  ]
}

Referencing to nested models

In some cases, you might want to reference to a nested model.

You can use the identifier, it will reference to an instance of the Binding you specified, in this case it would be an instance of ModelBinding.

Accessing the reference:

src/model/model.binding.js

import { Binding } from "domodel" // you could import the library again and run yet another model inside this model

class extends Binding {

  onCreated() {

    console.log(this.identifier.model) // returns an instance of ModelBinding
    // You could access the root element of the nested model through:
    console.log(this.identifier.model.root)
    // and much more...

  }

}

export default class 

API

See http://domodel.unificator.me.

Extensions

See https://github.com/topics/domodel-extension.

Demos

See https://github.com/topics/domodel-demo.

Testing

• npm install
• npm test