angular-decorators

angular-decorators

angular-decorators is a library of ES7 decorators for writing Angular 2 style code in AngularJS.

Installation via npm

npm install angular-decorators --save

Installation via jspm

jspm install angular-decorators

Looking for the 0.1x docs?

Modules

The standard angular.module does not understand the metadata attached to your classes from this library's decorators. Use the provided Module function to create decorator-friendly Angular modules:

import {Module} from 'angular-decorators';

// Create a new module:
let myModule = Module('my-module', ['ui.bootrap', 'ui.router']);

// Reference a pre-existing module:
let otherModule = Module('my-module');

All decorated classes are added to the module using add:

import {Service, Module} from 'angular-decorators';

@Service('MyService')
class MyService{ }

Module('my-module', []).add(MyService);

If you need the raw angular.module, use the publish function:

let angularModule = myModule.add(AnnotatedClass).publish();

Modules alias config and run blocks to the internal angular-module:

Module('example', []).config(...).run(...);

Module Dependencies

You do not need to publish a module to add it as a dependency to another module:

let myModule = Module('my-module', []);
let otherModule = Module('other-module', [ myModule ]);

This works for vanilla AngularJS modules as well:

let otherModule = angular.module('other-module', []);
let myModule = Module('my-module', [ otherModule ]);
let lastModule = angular.module('last-module', [ myModule.name ]);

Decorators

The decorators provided in this package follow this proposal. They work by adding metadata to your classes under the $ng-decs namespace using the reflect-metadata polyfill.

Inject

The @Inject decorator lets you specify dependencies:

@Inject('$q', '$http')
class MyService{
	constructor($q, $http){

	}
}

When inheriting from a decorated class, child dependencies are specified before parent dependencies letting you capture parent dependencies using a rest parameter:

@Inject('$q', '$http')
class Parent{
	constructor($q, $http){

	}
}

@Inject('$timeout')
class Child extends Parent{
	constructor($timeout, ...parentDependencies){
		super(...parentDependencies);
	}
}

Component

The @Component decorator lets you create components in AngularJS by wrapping the directive API and setting you up with sensible defaults:

import {Component, Inject, Module} from 'angular-decorators';

@Component({ selector : 'my-component' })
@Inject('$q')
class MyComponentCtrl{
	constructor($q){ ... }
}

export default Module('my-component-module', []).add(MyComponentCtrl);

The directive definition object generated for the above component is:

{
  controller: ['$q', MyComponentCtrl],
  controllerAs: 'myComponent',
  bindToController: true,
  scope: {},
  restrict: 'E'
}

Binding Element Attributes to the Controller

Supply an array of properties key of your config object using Angular 2 property syntax:

@Component({
	selector: 'my-component',
	properties: [
		'myProp: =renamedProp',
		'@anotherAttribute'
	]
})
class MyComponentCtrl

This becomes:

.directive('myComponent', function(){
	return {
		restrict: 'E',
		controller: function MyComponentCtrl{ },
		controllerAs: 'myComponent',
		scope: {},
		bindToController: {
			'myProp' : '=renamedProp',
			'anotherAttribute' : '@'
		}
	}
})

For information on attribute binding, view the AngularJS docs on scopes.

Renaming controllerAs

By default, the controllerAs property is a camelCased version of your selector (i.e. my-own-component's controllerAs would be myOwnComponent'). You can override this by specifying a new name in the @Component config object:

@Component({
	selector: 'my-component',
	controllerAs: 'vm'
})

Changing Scope

By default, components create new, isolate scopes but this can be manually set in the component config object:

@Component({
	selector: 'my-component',
	scope: false
})

Setting the Template

Templates are added with the @View decorator. Pass in a config object with either an inline template or a templateUrl:

import {Component, View} from 'angular-decorators';

@Component({ selector: 'my-component' })
@View({ template: `<h1>My Component Template</h1>` })
class MyComponentCtrl{ ... }

@Component({ selector: 'another-component' })
@View({ templateUrl: '/path/to/template.html' })
class AnotherComponentCtrl{ ... }

Requiring Other Directives

Use the @Require decorator to require directive controllers and access them using the static link function:

import {Component, Require} from 'angular-decorators';

@Component({ selector : 'my-component' })
@Require('^parent', 'myComponent')
class MyComponent{
	static link(scope, element, attrs, controllers){
		let [parent, self] = controllers;

		self.parent = parent;
	}
}

Transclusion

Use the @Transclude decorator to setup transclusion for your component:

import {Component, Transclude} from 'angular-decorators';

@Component({ selector: 'my-component' })
@Transclude
class MyComponent{ ... }

Directive

Unlike @Component, @Directive does not create a new isolate scope by default nor does it expose your directive's controller on the scope. It can only be used for directives that you want to restrict to a class name or attribute:

import {Directive} from 'angular-decorators';

@Directive({ selector: '[my-attr]' })
class MyAttrCtrl{
	constructor(){

	}
}

@Directive({ selector: '.my-class' })
class MyClassCtrl{
	constructor(){

	}
}

Filter

The @Filter decorator lets you write class-based filters similar to Angular 2's Pipes:

import {Filter, Module} from 'angular-decorators';

@Filter('trim')
class TrimFilter{
  // Implementing a supports function is encouraged but optional
	supports(input){
		return (typeof input === 'string');
	}
	transform(input, param){
		return input.trim();
	}
}

export default Module('trim-filter', []).add(TrimFilter);

The supports function is an optional test against the input. If the supports function returns false the generated filter will throw an error instead of applying the transform.

Service

The @Service decorator turns your class into a service:

import {Service, Inject, Module} from 'angular-decorators';

@Service('MyService')
@Inject('$q')
class MyService{
	constructor($q){
		this.$q = $q;
	}
}

export default Module('my-service', []).add(MyService);

Factory

The @Factory decorator is a complex decorator that assumes you have a class that requires more parameters on instantiation than what will be provided by AngularJS's injector. For example, if you had a class that looked like this:

@Inject('$http')
class Post{
	constructor($http, title, content){

	}
}

and you wanted to make a factory that created a new Post with a parameters for title and content, you would use @Factory:

import {Factory, Inject, Module} from 'angular-decorators';

@Factory('PostFactory')
@Inject('$http')
class Post{
	constructor($http, title, content){

	}
}

export default Module('post-factory', []).add(Post);

When injected elsewhere use the factory like this:

import {Inject, Service, Module} from 'angular-decorators';
import PostFactory from './post-factory';

@Service('SomeService')
@Inject('PostFactory')
class SomeService{
	constructor(PostFactory){
		let post = PostFactory('Title', 'Some content');
	}
}

export default Module('some-service', [PostFactory]).add(SomeService);

You can override the default factory function by implementing a static create function:

import {Factory, Inject, Module} from 'angular-decorators';

@Factory('CommentFactory')
@Inject('$http', '$q')
class Comment{
	constructor($http, $q, postID, comment){

	}

	static create(dependencies, post, comment){
		return new Comment(...dependencies, post.id, comment);
	}
}

export default Module('comment-factory', []).add(Comment);

Extending angular-decrators

Adding Your Own Providers

You can register your own providers using Module.addProvider. For instance, if you want to add a new decorator called @RouteableComponent that hooked up a component to the upcoming router, you would start by creating a decorator that set a provider name and type on a class:

import {providerWriter} from 'angular-decorators/writers';

export default const RouteableComponent = name => targetClass => {
  providerWriter.set('type', 'routeable-component', targetClass);
  providerWriter.set('name', name, targetClass);
}

Then you'll need to register your custom parser:

import Module from 'angular-decorators/module';

Module.addProvider('routeable-component', (provider, name, injectables, ngModule) => {
  // implement parsing logic here, adding necessary config/directives/etc to the raw ngModule
});

Your parser will be called each time a provider is added to a Module that has the provider type you've specified.

Extending the Directive Parser

The directive definiton object is derived from all key/value pairs set with the componentWriter. Here is an example of creating a priority decorator that sets a directive's priority:

import {componentWriter} from 'angular-decorators/writers';

export const Priority = level => target => componentWriter.set('priority', level, target);

No other configuration is required. Simply using @Priority in tandem with @Component or @Directive will work.

Changelog

v1.0.2

Fixed bug where properties were parsed incorrectly Property declarations now have full support for watch collection and optional symbols:

@Component({
  selector: 'example',
  properties: [
    '=*first',
    '=?second',
    '=*?third'
  ]
})