node.js +mongdb项目环境搭载及实现登录功能

一、开发环境准备

 //初始化仓库
npm init -y 
//安装koa和路由模块
npm i koa koa-router -S 
npm i nodemon -S

二、开启node服务

//index.js
const koa = require("koa");
const router = require("koa-router")();
const app = new koa();
router.get("/",async ctx=>{
    ctx.body = "我是首页"
})
app.use(router.routes());
app.listen(8080);

三、配置art-template

3-1 安装依赖

npm install koa-art-template art-template -S

四、拆分路由系统

//routers-index.js
const router = require("koa-router")();
router.get("/", async ctx => {
    await ctx.render('index');
})
module.exports = router;

//index.js
const koa = require("koa");
const router = require('./routers/index.js');
const render = require('koa-art-template');
const app = new koa();
const path = require("path");
render(app, {
    root: path.join(__dirname, 'views'),
    extname: '.html',
    debug: process.env.NODE_ENV !== 'production'
});

app.use(router.routes());
app.listen(8080);

五、初始化项目的配置文件

//init-config.js
const path = require("path");
const render = require('koa-art-template');
const router = require('../routers/index');
function initConfig(app) {
    // process.cwd()可以读取项目的路径
    render(app, {
        root: path.join(process.cwd(), 'views'),
        extname: '.html',
        debug: process.env.NODE_ENV !== 'production'
    });

    app.use(router.routes());
}
module.exports = initConfig;

//index.js
const koa = require("koa");
const app = new koa();
let initConfig = require('./init/config');
initConfig(app);
app.listen(8080);

六、MVC设计项目结构

model  -->数据层
views  -->视图层
controllers -->视图控制层

//routers--index.js
const router = require("koa-router")();
const controllers = require("../controllers");
// 只写文件名默认会读取文件里的index.js
router.get("/", controllers.index)
module.exports = router;

//controller--index.js
let index = async ctx=>{
    await ctx.render('index');
}
module.exports = {
    index
}

七、获取post传值

//1.安装依赖
npm i koa-bodyparser -S

//2.进行项目的配置
var Koa = require('koa');
var bodyParser = require('koa-bodyparser');

var app = new Koa();
app.use(bodyParser());

app.use(async ctx => {
   //3.取值 ctx.request.body
  ctx.body = ctx.request.body;
});

八、连接数据库

npm i mongoose -S

//models --db.js
const mongoose = require('mongoose');
mongoose.connect( 'mongodb://127.0.0.1:27017/studentManage', {useNewUrlParser: true},(err)=>{
    if(err) throw err;
    console.log("database连接成功")
});
module.exports = mongoose;

//models --user.js
var mongoose = require('./db');
var UserSchema = new mongoose.Schema({
    name:String,
    pwd:String
})
var User =  mongoose.model('User',UserSchema,'user');
module.exports = User;

//controllers --  index.js
let doLogin = async ctx=>{
    let {user,pwd} = ctx.request.body;
    let data = await UserModel.find({name:user,pwd});
    console.log(data);
    // 数据库中有对应的用户名密码则数组有东西,没有则数组没东西
    if(data.length>0){
        /* 登录成功 */
        ctx.body = "登录成功"
    }else{
        ctx.body = "用户名和密码不存在"
    }   
}

九.添加静态资源

koa常用中间件——koa-static
koa-static 是用于加载静态资源的中间件，通过它可以加载css、js等静态资源；

安装 koa-static

npm i koa-static

使用koa-static

const path = require("path");
const static = require("koa-static");
app.use(static(path.join(__dirname,"public")));