injektor
With injektor (and almost of dependency injection libraries), one can manage the service objects in a common "place" called container and doesn't care to assign the dependent parameters to a service when it is invoked.
Usage
Install injektor module:
$ npm install --save injektorIn your program, create the container:
var Injektor = require('injektor');
var injektor = new Injektor();Register a object or define a service with some dependencies:
injektor.registerObject('greeting', {
greet: function() { return 'Hello world!'; }
});
injektor.defineService('service1', function(fullname) {
var self = fullname;
this.sayHello = function(name) {
console.log('Hello ' + name + ". I'm " + self);
};
}).registerObject('fullname', 'Computer');
injektor.defineService('service2', function() {
this.sayWellcome = function(name) {
console.log('Wellcome to ' + name);
};
});Use the lookup() method to get services or invoke() method to evaluate the services:
injektor.lookup('service1').sayHello('Ubuntu');
injektor.invoke(function (greeting, service1, service2) {
console.log(greeting.greet());
console.log('\n');
service1.sayHello('Injektor');
service2.sayWellcome('Vietnam');
});The Console should display the text below:
Hello world!
Hello Injektor. I'm Computer
Wellcome to Vietnam
Dependency Annotations
Object schema annotation
var Injektor = require('injektor');
var injektor = new Injektor();
var MyResource = function(params) {
params = params || {};
var fullname = params.fullname;
var document = params.document;
this.process = function(action) {
console.log('The developer %s will %s the document %s',
fullname, action, JSON.stringify(document));
};
};
MyResource.argumentSchema = {
"type": "object",
"properties": {
"fullname": { "type": "string" },
"document": { "type": "object" }
}
};
injektor.defineService('myResource', MyResource)
.registerObject('fullname', 'Peter Pan')
.registerObject('document', {
type: 'Book',
content: 'Peter and Wendy'
});
injektor.lookup('myResource').process('open');The Console will display the text: 'The developer Peter Pan will open the document {"type":"Book","content":"Peter and Wendy"}'.
Object properties annotation
var Injektor = require('injektor');
var injektor = new Injektor();
var MyResource = function(params) {
params = params || {};
var fullname = params.fullname;
var document = params.document;
this.process = function(action) {
console.log('The developer %s will %s the document %s',
fullname, action, JSON.stringify(document));
};
};
MyResource.argumentProperties = [ "fullname", "document" ];
injektor.defineService('myResource', MyResource)
.registerObject('fullname', 'Peter Pan')
.registerObject('document', {
type: 'Book',
content: 'Peter and Wendy'
});
injektor.lookup('myResource').process('open');The Console will display the text: 'The developer Peter Pan will open the document {"type":"Book","content":"Peter and Wendy"}'.
Explicit name annotation
var Injektor = require('injektor');
var injektor = new Injektor();
injektor
.defineService('recipe', ['steps', 'object',
function(steps, object) {
steps = steps || [];
this.action = function(name) {
console.log('Hello, the instruction of %s is:', name);
steps.forEach(function(step) {
console.log(' - %s the %s', step, object);
});
};
}
])
.registerObject('steps', [
'clean', 'boil', 'peel', 'eat'
])
.registerObject('object', 'Eggs');
injektor
.invoke(['recipe', function(rp) {
rp.action('Peter Pan');
}]);Implicit name annotation
var Injektor = require('injektor');
var injektor = new Injektor();
injektor
.defineService('recipe', function(steps, object) {
steps = steps || [];
this.action = function(name) {
console.log('Hello, the instruction of %s is:', name);
steps.forEach(function(step) {
console.log(' - %s the %s', step, object);
});
};
});
injektor
.registerObject('steps', [
'clean', 'boil', 'peel', 'eat'
])
.registerObject('object', 'Eggs');
injektor.lookup('recipe').action('Peter Pan');