The NodeDependencyInjection component allows you to standarize and centralize the way objects are constructed in your application.
The Node Dependency Injection component allows you to standardize and centralize the way objects are constructed in your application.
npm install --save node-dependency-injection
Imagine you have a Mailer
class like this:
// services/Mailer.js
export default class Mailer {
/**
* @param {ExampleService} exampleService
*/
constructor(exampleService) {
this._exampleService = exampleService;
}
...
}
You can register this in the container as a service:
import {ContainerBuilder} from 'node-dependency-injection'
import Mailer from './services/Mailer'
import ExampleService from './services/ExampleService'
let container = new ContainerBuilder()
container
.register('service.example', ExampleService)
container
.register('service.mailer', Mailer)
.addArgument('service.example')
And get services from your container
const mailer = container.get('service.mailer')
import {ContainerBuilder, Autowire} from 'node-dependency-injection'
const container = new ContainerBuilder(
false,
'/path/to/src'
)
const autowire = new Autowire(container)
await autowire.process()
or from yaml-json-js configuration
# /path/to/services.yml
services:
_defaults:
autowire: true
rootDir: "/path/to/src"
You can also get a service from a class definition
import SomeService from '@src/service/SomeService'
container.get(SomeService)
If you are transpiling your Typescript may you need to dump the some kind of service configuration file.
import {ContainerBuilder, Autowire, ServiceFile} from 'node-dependency-injection'
const container = new ContainerBuilder(
false,
'/path/to/src'
)
const autowire = new Autowire(container)
autowire.serviceFile = new ServiceFile('/some/path/to/dist/services.yaml')
await autowire.process()
My proposal for load configuration file in a production environment with transpiling/babel compilation:
if (process.env.NODE_ENV === 'dev') {
this._container = new ContainerBuilder(false, '/src');
this._autowire = new Autowire(this._container);
this._autowire.serviceFile = new ServiceFile('/some/path/to/dist/services.yaml');
await this._autowire.process();
} else {
this._container = new ContainerBuilder(false, '/dist');
this._loader = new YamlFileLoader(this._container);
await this._loader.load('/some/path/to/dist/services.yaml');
}
await this._container.compile();
You can also use configuration files to improve your service configuration
# /path/to/file.yml
services:
service.example:
class: 'services/ExampleService'
service.mailer:
class: 'services/Mailer'
arguments: ['@service.example']
import {ContainerBuilder, YamlFileLoader} from 'node-dependency-injection'
let container = new ContainerBuilder()
let loader = new YamlFileLoader(container)
await loader.load('/path/to/file.yml')
And get services from your container easily
...
const mailer = container.get('service.mailer')
Please read full documentation
If you are using expressJS and you like Node Dependency Injection Framework then I strongly recommend
you to use the node-dependency-injection-express-middleware
package.
That gives you the possibility to retrieve the container from the request.
npm install --save node-dependency-injection-express-middleware
import NDIMiddleware from 'node-dependency-injection-express-middleware'
import express from 'express'
const app = express()
const options = {serviceFilePath: 'some/path/to/config.yml'}
app.use(new NDIMiddleware(options).middleware())
If you are using typescript and you like Node Dependency Injection Framework then typing are now provided at node-dependency-injection
so
you do not have to create custom typing anymore.
npm install --save node-dependency-injection
import { ContainerBuilder } from 'node-dependency-injection'
import MongoClient from './services/MongoClient'
import { Env } from './EnvType'
export async function boot(container = new ContainerBuilder(), env: Env) {
container.register('Service.MongoClient', MongoClient).addArgument({
host: env.HOST,
port: env.PORT,
})
}