koa2 装饰器模式控制路由

基本用法

Koa 装饰器类

import { resolve } from 'path'
import KoaRouter from 'koa-router'
import glob from 'glob'
import R from 'ramda'

const pathPrefix = Symbol('pathPrefix')
const routeMap = []
let logTimes = 0

const resolvePath = R.unless(
  R.startsWith('/'),
  R.curryN(2, R.concat)('/')
)

const changeToArr = R.unless(
  R.is(Array),
  R.of
)

export class Route {
  constructor (app, routesPath) {
    this.app = app
    this.router = new KoaRouter()
    this.routesPath = routesPath
  }

  init = () => {
    const { app, router, routesPath } = this

    glob.sync(resolve(routesPath, './*.js')).forEach(require)

    R.forEach(
      ({ target, method, path, callback }) => {
        const prefix = resolvePath(target[pathPrefix])
        router[method](prefix + path, ...callback)
      }
    )(routeMap)

    app.use(router.routes())
    app.use(router.allowedMethods())
  }
}

export const convert = middleware => (target, key, descriptor) => {
  target[key] = R.compose(
    R.concat(
      changeToArr(middleware)
    ),
    changeToArr
  )(target[key])
  return descriptor
}

export const setRouter = method => path => (target, key, descriptor) => {
  routeMap.push({
    target,
    method,
    path: resolvePath(path),
    callback: changeToArr(target[key])
  })
  return descriptor
}

export const Controller = path => target => (target.prototype[pathPrefix] = path)

export const Get = setRouter('get')

export const Post = setRouter('post')

export const Put = setRouter('put')

export const Delete = setRouter('delete')

export const Log = convert(async (ctx, next) => {
  logTimes++
  console.time(`${logTimes}: ${ctx.method} - ${ctx.url}`)
  await next()
  console.timeEnd(`${logTimes}: ${ctx.method} - ${ctx.url}`)
})

export const Auth = convert(async (ctx, next) => {
  if (!ctx.session.user) {
    return (
      ctx.body = {
        success: false,
        errCode: 401,
        errMsg: '登陆信息已失效, 请重新登陆'
      }
    )
  }
  await next()
})

在相关实例中的应用

import {
  Controller,
  Get,
  Required,
} from '../decorator/router'
import { getAllProducts, getDetailProduct } from '../service/Product'

@Controller('/product')
export default class ProductController {
  @Get('/all')
  async getProductList (ctx, next) {
    const products = await getAllProducts(type, year)

    ctx.body = {
      data: products,
      success: true
    }
  }

  @Get('/detail/:id')
  async getProductDetail (ctx, next) {
    const id = ctx.params.id
    const product = await getDetailProduct(id)
    ctx.body = {
      data: product,
      success: true
    }
  }
}