express-路由（router）

后端：一个路由就是一个小的服务(server/app)
前端：路由就告诉你应该去哪儿

1. 路由操作(简易)

   1. let routerUser = express.Router();//返回路由对象
   2. server.use(‘/user’,routerUser);//响应的处理过程
   3. 处理过程:
      • router.get(‘/‘,fn);
      • router.get(‘/1’,fn);
      • router.get(‘/2’,fn);
      • router.get(‘/3’,fn);

2. 路由操作(常用)

   //	1. 主服务（server.js/index.js）
   let express = require('express');
   let multer = require('multer');
   let cookieParser = require('cookie-parser');
   let cookieSession = require('cookie-session');
   let bodyParser = require('body-parser');
   let consolidate = require('consolidate'); //中间件，管理多个模板引擎
   let mysql = require('mysql');
   let server = express();
   server.listen(8001,function(){
   trueconsole.log('server is running');
   });
   server.use(express.static('./www'));
   server.use(bodyParser.urlencoded({limit:5*1024}));
   let objMulter = multer({dest:'upload'});
   server.use(objMulter.any());
   server.set('views','./views');//设置模板引擎目录
   server.set('view.engine','html');//设置输出类型
   server.engine('html',consolidate.ejs);//输出与模板匹配
   //cookie session
   server.use(cookieParser());
   // let arr=[];
   // for(let i=0;i<10000;i++){
   //   arr.push('myse'+Math.random());
   // }
   server.use(cookieSession({
     keys:['aa','bb'],//加密
     name:'session',//sessionkey为session
     maxAge:1000*10//10秒后过期
   }));
   //创建数据库连接池
   let db = mysql.createPool({
   truehost:'localhost',
   trueuser:'root',
   truepassword:'123456',
   truedatabase:'test'
   });
   server.use('/',require('./router/home')(db))
   server.use('/article',require('./router/article')(db));
   server.use('/column',require('./router/column')(db));
   server.use('/fllow',require('./router/fllow')(db));
   server.use('/user',require('./router/user')(db));
   server.use('/login',require('./router/login')(db));
   server.use('/reg',require('./router/reg')(db));
   //2.新建router文件
   //在router文件中写各个服务模块
   //`column模块`示例：
   let express = require('express');
   module.exports=function(db){
   truelet router =express.Router(); 
   truerouter.get('/',(req,res)=>{
   truetruelet sql = `select * from news`;
   truetruedb.query(sql,(err,data)=>{
   truetruetrueres.render('column_m.ejs',{news:data});
   truetrue})
   true})
   truereturn router;
   }