app.js

var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');

var indexRouter = require('./routes/index');
var usersRouter = require('./routes/users');
var loginRouter = require('./routes/login');
var chatRouter = require('./routes/chat');

//引入
var session = require("express-session")
const MongoStore = require("connect-mongo");
const JWT = require('./util/JWT');
var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

//注册session中间件
app.use(session({
  name: "kerwinsystem",
  secret: "dwad4489384dawdwa",
  cookie: {
    maxAge: 1000 * 60 * 60,
    secure: false
  },
  resave: true, //重新设置session后， 会自动重新计算过期时间
  saveUninitialized: true,
  store: MongoStore.create({
    mongoUrl: 'mongodb://127.0.0.1:27017/kerwin_session', //新创建了一个数据库
    ttl: 1000 * 60 * 60 // 过期时间
  })
}))

//设置中间件，token过期校验

app.use((req, res, next) => {
  //排除login相关的路由和接口
  if (req.url.includes("login")) {
    next()
    return
  }

  const token = req.headers["authorization"]?.split(" ")[1]
  if (token) {
    const payload = JWT.verify(token)
    if (payload) {
      //重新计算token过期时间
      const newToken = JWT.generate({
        _id: payload._id,
        username: payload.username
      }, "1d")
      res.header("Authorization", newToken)
      next()
    } else {
      res.status(401).send({ errCode: -1, errInfo: "token过期" })
    }
  } else {
    next()
  }
})

app.use('/', indexRouter);
app.use('/api', usersRouter);
app.use('/login', loginRouter);
app.use('/chat', chatRouter);

// catch 404 and forward to error handler
app.use(function (req, res, next) {
  next(createError(404));
});

// error handler
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;