关于会话
会话是指服务器以浏览器维度提供的上下文缓存。服务器通过在 cookie 或者 url 中维护唯一 id 来索引和管理会话缓存。会话缓存是跨服务器多个应用节点共享的，应用节点通过会话模块有序访问会话缓存：
缓存模块
Express 官方提供的会话模块 express-session 非常灵活，可以通过 store 参数任意替换会话缓存的存储方式。性能优先的方式是使用 connect-redis 存储在 Redis 缓存服务中，成本优先的方式是使用 connect-session-sequelize 存储在数据库里，本文采用成本优先的方式存储会话缓存。在上一章已完成的工程 host1-tech/nodejs-server-examples - 05-database 的根目录执行以下安装命令：
$ yarn add express-session # 本地安装 express-session
# ...
info Direct dependencies
└─ [email protected]
# ...
$ # 本地安装 connect-session-sequelize 6.x 版本，配合 sequelize 5.x 版本
$ yarn add 'connect-session-sequelize@^6.1.1'
# ...
info Direct dependencies
└─ [email protected]
# ...考虑到其他使用 cookie 的情况安装 cookie-parser 统一提供 cookie 处理逻辑：
$ yarn add cookie-parser # 本地安装 cookie-parser
# ...
info Direct dependencies
└─ [email protected]
# ...简易登录
现在为店铺管理加上简易的登录功能。先创建 session 数据库表格结构：
$ # 生成会话 schema 迁移文件
$ yarn sequelize migration:generate --name create-session
$ tree src/models/migrate # 展示 src/models/migrate 目录内容结构
src/models/migrate
├── 20200725045100-create-shop.js
└── 20200727025727-create-session.js美化一下 src/models/migrate/20200727025727-create-session.js：
// src/models/migrate/20200727025727-create-session.js
module.exports = {
up: async (queryInterface, Sequelize) => {
/**
* Add altering commands here.
*
* Example:
* await queryInterface.createTable('users', { id: Sequelize.INTEGER });
*/
},
down: async (queryInterface, Sequelize) => {
/**
* Add reverting commands here.
*
* Example:
* await queryInterface.dropTable('users');
*/
},
};调整一下 src/models/migrate/20200727025727-create-session.js：
// src/models/migrate/20200727025727-create-session.js
module.exports = {
up: async (queryInterface, Sequelize) => {
- /**
- * Add altering commands here.
- *
- * Example:
- * await queryInterface.createTable('users', { id: Sequelize.INTEGER });
- */
+ await queryInterface.createTable('session', {
+ sid: {
+ type: DataTypes.STRING(36),
+ },
+ expires: {
+ type: DataTypes.DATE,
+ },
+ data: {
+ type: DataTypes.TEXT,
+ },
+
+ created_at: {
+ allowNull: false,
+ type: Sequelize.DATE,
+ },
+ updated_at: {
+ allowNull: false,
+ type: Sequelize.DATE,
+ },
+ });
},
down: async (queryInterface, Sequelize) => {
- /**
- * Add reverting commands here.
- *
- * Example:
- * await queryInterface.dropTable('users');
- */
+ queryInterface.dropTable('session');
},
};向数据库写入 session 表格结构：
$ yarn sequelize db:migrate # 向数据库写入表格结构，db:migrate 会根据 sequelize_meta 记录只创建 session 表格结构接下来初始化会话模块并补充登录验证的逻辑：
// src/controllers/login.js
const { Router } = require('express');
class LoginController {
async init() {
const router = Router();
router.post('/', this.post);
return router;
}
post = (req, res) => {
req.session.logined = true;
res.redirect('/');
};
}
module.exports = async () => {
const c = new LoginController();
return await c.init();
};// src/controllers/index.js
const { Router } = require('express');
const shopController = require('./shop');
const chaosController = require('./chaos');
const healthController = require('./health');
+const loginController = require('./login');
module.exports = async function initControllers() {
const router = Router();
router.use('/api/shop', await shopController());
router.use('/api/chaos', await chaosController());
router.use('/api/health', await healthController());
+ router.use('/api/login', await loginController());
return router;
};// src/middlewares/login.js
const { parse } = require('url');
module.exports = function loginMiddleware(
homepagePath = '/',
loginPath = '/login.html',
whiteList = {
'/500.html': ['get'],
'/api/health': ['get'],
'/api/login': ['post'],
}
) {
whiteList[loginPath] = ['get'];
return (req, res, next) => {
const { pathname } = parse(req.url);
if (req.session.logined && pathname == loginPath) {
res.redirect(homepagePath);
return;
}
if (
req.session.logined ||
(whiteList[pathname] &&
whiteList[pathname].includes(req.method.toLowerCase()))
) {
next();
return;
}
res.redirect(loginPath);
};
};// src/middlewares/session.js
const session = require('express-session');
const sessionSequelize = require('connect-session-sequelize');
const { sequelize } = require('../models');
module.exports = function sessionMiddleware(secret) {
const SequelizeStore = sessionSequelize(session.Store);
const store = new SequelizeStore({
db: sequelize,
modelKey: 'Session',
tableName: 'session',
});
return session({
secret,
cookie: { maxAge: 7 * 24 * 60 * 60 * 1000 },
store,
resave: false,
proxy: true,
saveUninitialized: false,
});
};// src/middlewares/index.js
const { Router } = require('express');
+const cookieParser = require('cookie-parser');
+const sessionMiddleware = require('./session');
const urlnormalizeMiddleware = require('./urlnormalize');
+const loginMiddleware = require('./login');
+
+const secret = '842d918ced1888c65a650f993077c3d36b8f114d';
module.exports = async function initMiddlewares() {
const router = Router();
router.use(urlnormalizeMiddleware());
+ router.use(cookieParser(secret));
+ router.use(sessionMiddleware(secret));
+ router.use(loginMiddleware());
return router;
};// src/server.js
// ...
async function bootstrap() {
+ server.use(await initMiddlewares());
server.use(express.static(publicDir));
server.use('/moulds', express.static(mouldsDir));
- server.use(await initMiddlewares());
server.use(await initControllers());
server.use(errorHandler);
await promisify(server.listen.bind(server, port))();
console.log(`> Started on port ${port}`);
}
// ...访问 http://localhost:9000/ 即可看到效果：
本章源码
host1-tech/nodejs-server-examples - 06-session
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