搭建koa服务器，模拟数据请求

针对后端只提供了文档，没有部署求访问接口的情况，需模拟搭建请求访问的请求服务器
方式有很多，比如设置mock服务器，另外就是本地搭建后端服务，模拟请求访问

koa搭建服务器方式如下（本例koa服务启动的是8080端口，项目启动不带端口）

启动文件 - server.js

const Koa = require("koa");
//const KoaStatic = require("koa-static");
const cors = require("@koa/cors");
const router = require("./router");
const app = new Koa();

// 利用@koa/cors处理跨域问题
app.use(
    cors({
        credentials: true, // 必须设置为true
    })
);

 //设置静态资源访问地址
// app.use(KoaStatic(__dirname + "/static"));

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

app.listen("8080", () => {
    console.log("koa server start");
});

配置路由文件 - router/index.js

const KoaRouter = require("koa-router");
const router = new KoaRouter();

const schoolList = require("../data/schoolList.json");
const classList = require("../data/classList.json");
const studentList = require("../data/studentList.json");

router.post(
    "/common/data/query/schoolList",
    (ctx, next) => {
        ctx.body = schoolList;
        next();
    }
);

router.post(
    "/common/data/query/schoolList",
    (ctx, next) => {
        ctx.body = classList;
        next();
    }
);

router.post(
    "/common/data/query/studentList",
    (ctx, next) => {
        ctx.body = studentList;
        next();
    }
);

router.get("/index", (ctx, next) => {
	ctx.body = " this is index";
	next();
});

module.exports = router;