koa-router 基本使用

app.js

const Koa = require("koa");
const Route = require("koa-router");
const app = new Koa();
      
const router = Route();

router
  .get("/", async (ctx, next) => {
    ctx.body = "Hello World";
    console.log("get");
    await next()
  })
  .all("/", async (ctx, next) => {
    console.log("all");
    await next()
  });

app.use(router.routes());

app.listen(3000, () => {
  console.log("Server is running at http://localhost:3000");
});

all() 方法可以用来设置请求头

router.all("/*", async (ctx, next) => {
  // 符号* 代表允许来自所有域名的请求
  ctx.set("Access-Control-Allow-Origin", "https://www.example.com");
  await next();
});