@vyke/dency NPM

Simple and lightweight dependency injection for vanilla JavaScript and TypeScript

Features

No decorators, no annotations, no classes
Simple API
Scoped, singleton and transient dependencies
TypeScript support
No dependencies
Tiny size

Installation

npm i @vyke/dency

Examples

import { defineInjectable, inject } from '@vyke/dency'

const getHello = defineInjectable(() => 'Hello')
const getWorld = defineInjectable(() => 'World')
const getHelloWorld = defineInjectable((hello = inject(getHello), world = inject(getWorld)) => `${hello}, ${world}!`)
// the three dependencies are singletons by default

const helloWorld = inject(getHelloWorld) // Hello, World!

With Scopes

import { createScope, defineInjectable, inject } from '@vyke/dency'
const firstScope = createScope()
const secondScope = createScope()

const getTheme = defineInjectable(() => {
	let color = 'light'
	return { // the return value is the dependency and can be anything
		getColor: () => color,
		toogle: () => {
			color = color === 'light' ? 'dark' : 'light'
		}
	}
})

const createThemeToggle = defineDep((theme = inject(getTheme)) => {
	return {
		toogle: () => theme.toogle()
	}
}, { scopeTye: TRANSIENT_SCOPE })

// both toggles will have the same theme
// but they will be different instances
const toggle1 = firstScope.inject(createThemeToggle)
const toggle2 = secondScope.inject(createThemeToggle)

With Props

import { createScope, defineDep, inject, SCOPED_SCOPE } from '@vyke/dency'

const getHello = defineDep((name: string) => `Hello, ${name}!`)

const hello = inject(getHello, 'John') // Hello, John!

API

rootScope

The root scope. It is used by default if no scope is provided.

createScope

Create a new scope.

import { createScope, defineInjectable } from '@vyke/dency'

const scope = createScope()

const createDep = defineInjectable(() => 'foo', {
	scopeType: SCOPED_SCOPE
})

const myDep = scope.inject(createDep)

SINGLETON_SCOPE

Singleton scope type.

TRANSIENT_SCOPE

Transient scope type.

SCOPED_SCOPE

Scoped scope type.

SCOPE_TYPE

Scope types.

defineInjectable

Defines an injectable and returns it.

import { defineInjectable, SINGLETON_SCOPE } from '@vyke/dency'

const createDep1 = defineInjectable(() => {
	return 'Hello, World!'
}, { scopeType: SINGLETON_SCOPE })
const createDep2 = defineInjectable(() => {
	return 'Hello, World!'
}) // Default scope type is SINGLETON_SCOPE

inject

Injects an injectable and returns the instance.

import { defineInjectable, inject, SINGLETON_SCOPE } from '@vyke/dency'
const createDep = defineInjectable(() => {
	return 'Hello, World'
}, { scopeType: SINGLETON_SCOPE })
const dep = inject(createDep) // can be used anywhere

console.log(dep) // Hello, World

// but usually, it is used inside another injectable
const createDep1 = defineInjectable((dep = inject(createDep)) => {
	return `${dep}!`
})

console.log(inject(createDep1)) // Hello, World!

use

Returns the instance of an injectable if it exists.

import { defineInjectable, SINGLETON_SCOPE, use } from '@vyke/dency'
const createDep = defineInjectable(() => {
	return 'Hello, World'
})

const dep = use(createDep) // probably undefined