Installation
Koa requires node v12.17.0 or higher for ES2015 and async function support.
npm i koa-inversify
Full example of project
Hello koa-inversify
Features:
CLI
npx koa-inversify
Structure of project
repo
-src
--App.ts
--index.ts
--AppModule.ts
---some-domain-name
---SomeDomainService.ts
---SomeDomainModule.ts
---SomeDomainWebController.ts
Init
src/App.ts
import { KoaApplication } from 'koa-inversify'
import { injectable } from 'inversify'
@injectable()
export class App extends KoaApplication {
constructor(
@inject(TYPES.Options) { port }: { port: number },
// if you has custom logger you can use your own
readonly logger: Logger | undefined
) {
super({ port, logger })
}
async init(): Promise<void> {
// add here any middlewares you need (koa-body, koa-cors)
// maybe some connect to db
// this.use(koa-cors)
// this.use(koa-body)
}
}src/AppModule.ts
import { module } from 'koa-inversify'
import { SomeDomainModule } from './some-domain/SomeDomainModule'
export const TYPES = {
Options: Symbol('Options')
}
// you can create custom module in case
// you want to get options from config and bind it to some interface
@module()
export class AppModule {
static register(options: { port: number }): Module {
return {
imports: [SomeDomainModule],
deps: {
init(local) {
local.bind(App).toSelf().inSingletonScope()
local.bind(TYPES.Options).toConstantValue(options)
}
}
}
}
}Domain logic
src/some-domain/SomeDomainService.ts
import { inejctable } from 'inversify'
@injectable
export class SomeDomainService {
// here is your buisness logic
sayHello(): void {
console.log('Hello world')
}
}Middlewares
src/some-domain/middlewares/AuthMiddleware.ts
import { inejctable } from 'inversify'
import { middleware } from 'koa-inversify'
@middleware()
export class AuthMiddleware {
// here is your buisness logic
use(ctx: Context, next: Next): Promise<any> {
// some jwt or any other logic
}
}WebControllers
src/some-domain/SomeDomainWebController.ts
import { inejctable } from 'inversify'
import { get, useMiddleware, Context } from 'koa-inversify'
import { AuthMiddleware } from './middlewares/AuthMiddleware'
@webController('/some-domain')
export class SomeDomainWebController {
constructor(private readonly service: SomeDomainService) {}
//enpoint will be - GET http://localhost:port/some-domain/sayHello
@useMiddleware(AuthMiddleware)
@get('/sayHello')
sayHello(ctx: Context): void {
ctx.body = this.service.sayHello()
ctx.body = 200
}
}Domain Modules
src/some-domain/SomeDomainModule.ts
@module({
deps: {
init(container) {
container.bind(SomeDomainService).toSelf().inSingletonScope()
},
webControllers: [SomeDomainWebController]
}
})
export class SomeDomainModule {}Finally
./src/index.ts
import { ModuleFactory } from 'koa-inversify'
import { App } from './App'
function main(): Promise<void> {
const ioc = new ModuleFactory(AppModule.register({ port: 3000 }))
const app = ioc.get(App)
return app.start(ioc)
}
main()