Use express written Interface

I. Development Interface Specification (Restful API)

1, a clear demand

Role: to ensure everyone's written specifications as
an example:

Back-end resources posted to the URL -> URL to access resources through the front -> and indicates the operation to a resource via HTTP verbs
backend defined interfaces -> Front Request Interface -> HTTP verbs purpose operating table (get get new post put updates, etc.)

• For Li
  List: Access - / module name (get)
  details page: visit - / module name / number (get)
  add Page: Access - / module name / create (get)
  treatment: Access - / module name (post)
  modified page: access - / module name / number / edit (get)
  treatment: access - / module name / number (put)
  delete: access - / module name / number (delete)

HTTP verb: get, post, put, delete

Second, the initialization (Express scaffolding frame)

Scaffolding: It is a noun, not explain

Role: the scaffolding can be generated by the project code

1, the frame generating codes express express

• Manual: http://www.expressjs.com.cn/starter/generator.html

Step 1: mounting frame generator ( NPM the install Express-Generator -g )

Step 2: express command generated by the newly installed shopproject ( express project name )

Step 3: mounting frame dependent module

• cd shop
• npm install
  

Step 4: Start & Access test (foot care: command npm start)

So far express frame was set for. The following database connection and modularity

1, connected to a database (Modular)

• Step 1: & global function package global profile

Create a file common / config.json

{
	"db_config":{
		"host" : "localhost",  
		"port" : 27017,   // 数据库的端口号
		"dbname" : "sixbuyshop"  // 数据库的名字
	}
}

Create a file common / db.js

Pay attention: Copy the code below before the first [npm i mongoose]

// 导入模块
const mongoose = require('mongoose');
// 导入配置文件
const configObj = require(process.cwd() + "/common/config.json").db_config

// 连接数据库
const db = mongoose.createConnection(`mongodb://${configObj.host}:${configObj.port}/${configObj.dbname}`, {useNewUrlParser: true, useUnifiedTopology: true}, (err)=>{
    if(err){
        console.log('---------------------------------------')
        console.log('数据库连接失败：', configObj)
        console.log('---------------------------------------')
        return;
    }
    console.log('数据库连接成功');
})

// 声明全局变量  全局都可以用
global.db = db

Create a file common / utils.js

// http协议状态码（背 明晚抽查 说不出来30遍）
// 2XX  成功
// 		200-成功    正常返回     （服务器已成功处理了请求）     
// 		201-创建    成功创建数据 （表示服务器执行成功，并且创建了新的资源）     
// 		202-已接受              （服务器接受请求，但未处理）
// 3XX  重定向（服务器返回信息告知浏览器如何做后续操作才能成功处理请求）
//      301-永久（新网站）
//      302-临时（站内跳转）
//      304-浏览器缓存（请求成功检测为修改数据来源于浏览器）
// 4XX  客户端错误（客户端原因，妨碍了服务器的处理）
//      400-前端请求失败，方式参数不对
//      401-未通过 HTTP 认证的认证信息（场景：网页登录失败）
//      403-禁止访问（码云私有仓库）
//      404-文件不存在
//      405-请求方法有误 
// 5XX  服务端错误
//		500-服务器端在执行请求时发生了错误
//		503-服务器过载，无法处理请求
// -------------------------------

/**
 * 接口响应
 * @param {Object} res      响应对象
 * @param {Number} code     状态码
 * @param {String} message  提示信息
 * @param {mixed}  data     响应数据
 */
global.sendJson = (res, code, message, data = null) => {
    res.json({
        "meta" : {
            "state" : code,
            "msg" 	: message
        }, 
        "data" : data
    });
}

Inlet configuration files into the database

require(process.cwd() + “/common/db.js”)
require(process.cwd() + “/common/utils.js”)

Second, routing

1, steps to establish a route

Established home under the Home directory routing module routes

var express = require('express');
var router = express.Router();

// 以前直接在 这里写逻辑
// 但不知道有几个路由
// 解决 ：去controller目录中定义  这里调用
// process.cwd() 表示命令执行的文件路径
//const { getHomeBannerList } = require(process.cwd() + '/controller/home')

// 首页轮播
// router.get('/', getHomeBannerList )

/* GET users listing. */
router.get ('/', function(req, res, next) {
  res.send('respond with a resource');
});

module.exports = router;

app.js file import route activation

Using mvc thought to separate logic code
Model Model - responsible for data processing,
View View - responsible for displaying the page
Controller Controller - which M and which is responsible for scheduling the use of V

Method for establishing controller / home.js responsible for calling the next model

// const  { usersGetList } = require(process.cwd() + "/model/home")


  //用户列表
const getHomeBannerList = async (req, res, next) =>{
      // const userData =await usersGetList()
      sendJson(res, 200, "操作成功")
      // console.log(req.body)
      
    // const insertObj = req.body
    // const cbData=await usersModelPost(insertObj);

    // if(cbData){
    //     sendJson(res, 200, "操作成功",cbData)
    // }else{
    //     sendJson(res, 500, "操作失败",cbData);
    // }

}

module.exports={
  getHomeBannerList
}

The establishment of model / home.js write some logic code request database

const model = db.model('user',{
	name:{type:String},
    pwd:{type:String},
	sex:{type:String, default:"女"}
})
// 用户列表的查

const  usersGetList = ()=>{
    return model.find()  
      .then(res=>{
          return res
      })
      .catch(err=>{
          console.log('用户名查错误：'+ err)
          return null
      })
 }

module.exports={
    usersGetList
}