node+koa实现数据mock接口的方法

// server.js
const Koa = require('koa');
const Router = require('koa-router');
const qs = require('qs');
const assert = require('assert');

const app = new Koa();
const router = new Router();

/**
 * 获取列表数据
 * @param {request} page 页数
 * @param {request} limit 每页数据条数
 * @param {response} errno 返回状态码 0 ==> 返回成功 1 ==> 有错误
 * @param {response} hasMore 是否有更多数据
 */
let listData = require('./mock/list/list.js');

router.get('/api/getlist/:page/:limit', function (ctx, next) {
 
 const page = ctx.params.page;
 const limit = ctx.params.limit;
 const maxPage = listData.length / limit;
 
 // 构造返回对象
 let res = {
 errno: 0,
 data: {
 hasMore: true,
 data: []
 }
 };

 // 如果超过最大页面数
 if ((page*1 + 1) >= maxPage) {
 res.data.hasMore = false;
 }
 res.data.data = listData.slice(page*limit, page*limit + limit);
 ctx.body = res;
});

/**
 * 获取详情数据
 * @param {request} id 商品id
 */
const detailData = require('./mock/detail/detail.js');

router.get('/api/getdetail/:id', function (ctx, next) {

 const id = ctx.params.id
 let res = {
 errno: 0,
 data: {
 data: []
 }
 }
 res.data.data = detailData;
 // todo...
 ctx.body = res;
});

/**
 * 提交评论
 * @param {request} id 用户id
 * @param {request} uid 商品id
 * @param {request} msg 评论内容
 */
router.post('/api/comment', function (ctx, next) {
 
 const params = qs.parse(ctx.req._parsedUrl.query);
 const id = params.id;
 const uid = params.uid;
 const msg = params.msg;
 if (id === undefined || uid === undefined || msg === undefined) {
 ctx.body = {
 errno: 1,
 msg: '缺少参数'
 }
 } else {
 // todo...
 ctx.body = {
 errno: 0,
 msg: '评论成功'
 }
 }
});

app
 .use(router.routes())
 .use(router.allowedMethods());
app.listen(3000);
console.log("server is running at http://localhost:3000/");

module.exports = {
 ...

 devServer: {
 proxy: {
 // 将 `/api` 开头的 http 请求，都代理到 `localhost:3000` 上，由 koa 提供 mock 数据
 '/api': {
 target: 'http://localhost:3000',
 secure: false
 }
 }
 ...
 }
}