injecty

injecty is a micro library for dependency injection and inversion of control container in JavaScript. It's dependency-free, light and small (~200 SLOC). It was designed to be embedded in frameworks or libraries

It's intimately inspired in AngularJS DI and provides useful features such as autodiscover injections from arguments using pattern matching, creating multiple containers with inheritance support between them, AngularJS-style injections based on array notation and more

injecty is written in Wisp, a Clojure-like language which transpiles into plain JavaScript. It exploits functional programming common patterns such as lambda lifting, pure functions, higher-order functions, function composition and more

Installation

Node.js

npm install injecty

Browser

Via Bower

bower install injecty

Via Component

component install h2non/injecty

Or loading the script remotely

<script src="//cdn.rawgit.com/h2non/injecty/0.1.4/injecty.js"></script>

Environments

It works in any ES5 compliant engine

• Node.js
• Chrome >= 5
• Firefox >= 3
• Safari >= 5
• Opera >= 12
• IE >= 9

Basic usage

var injecty = require('injecty')

injecty.register('Request', XMLHttpRequest)
injecty.register('Log', console.log.bind(console))

function get(Request) {
  return function (url, cb) {
    var xhr = new Request()
    xhr.open('GET', url)
    xhr.onload = function () {
      if (xhr.readyState === 4) {
        cb(xhr.responseText)
      }
    }
    xhr.send()
    return xhr
  }
}

var get = injecty.invoke(get)
get('/test/sample.json', injecty.invoke(function (Log) {
  return Log // -> output body response
}))

API

injecty.container([parent])

Creates a new container. Optionally it can inherit from another container

// register a dependency in the global built-in container
injecty.register('Math', Math)
// creates new container which inherits from global
var container = injecty.container(injecty)
// check it was registered
container.injectable('Math') // -> true

injecty.get(name)

Alias: require

Retrieve a registered dependency by its name

injecty.get('Math') // -> {MathConstructor...}

injecty.register(name, value)

Alias: set

Register a new dependency in the container

injecty.register('Location', window.location)
injecty.injectable('Location') // -> true

You can also register functions that require injections

injecty.register('Date', Date)
injecty.register('now', injecty.inject(function (Date) {
  return new Date().getTime()
}))
var time = injecty.invoke(function (now) {
  return now()
})
console.log(time) // -> 1405170246959

Different ways to declare injections for consistency in browsers

Using the injection array notation

injecty.register('random', ['Math', function (m) {
  return m.random()
}])

Setting the $inject property in the function object

function random(m) {
  return m.random()
}
random.$inject = ['Math']
injecty.register('random', random)

injecty.invoke(fn/array)

Invoke a function injecting requested dependencies. Optinally you can supply the arguments to inject as array notation

var time = injecty.invoke(function (Date) {
  return new Date().getTime()
})
console.log(time) // -> 1405170246959

Using the array injection notation, useful for minification

var time = injecty.invoke(['Date', function (D) {
  return new D().getTime()
}])
console.log(time) // -> 1405170246959

injecty.inject(fn/array)

Inject dependencies and return the partial function

var time = injecty.inject(['Date', function (D) {
  return new D().getTime()
}])

injecty.annotate(fn/array)

Returns an array of names which the given function is requesting for injection

var injectables = injecty.annotate(function (Math, Date) {
  ...
})
console.log(injectables) // -> ['Math', 'Date']

function fn(m, d) {
  ...
}
fn.$inject = ['Math', 'Date']
var injectables = injecty.annotate(fn)
console.log(injectables) // -> ['Math', 'Date']

injecty.injectable(name)

Checks if a dependency was already registered and it's available to be injected

injecty.satisfies(fn)

Checks if can safisty all the requested dependecies to inject

inject.register('Math', Math)
inject.register('Date', Date)
inject.safisfies(function (Math, Date) {}) // -> true

injecty.remove(name)

Remove a registered dependency from the container

injecty.remove('Math').injectable('Math') // -> false

injecty.flush()

Flush all registered dependencies in the container

injecty.flush().injectable('Math') // -> false

injecty.dependencies()

Get an array of values with the registered dependency names in the container

Contributing

Wanna help? Cool! It will be appreciated :)

You must add new test cases for any new feature or refactor you do, always following the same design/code patterns that already exist

Tests specs are completely written in Wisp language. Take a look to the language documentation if you are new with it. You should follow the Wisp language coding conventions

Development

Only node.js is required for development

Clone this repository

$ git clone https://github.com/h2non/injecty.git && cd injecty

Install dependencies

$ npm install

Compile code

$ make compile

Run tests

$ make test

Browser sources bundle generation

$ make browser

License

MIT - Tomas Aparicio