node连接--MySQL

MySQL驱动器：node-mysql;

MySQL对象关系映射器：node-sequelize;

例子：

• package.json:

  {
  	"name": "shopping-cart-example",
  	"version": "0.0.1",
  	"dependencies": {
  		"express": "2.5.2",
  		"jade": "0.19.0",
  		"mysql": "0.9.5"
  	}
  }

• config.json:

  {
  	"host": "localhost",
  	"password": "123",
  	"database": "cart-example"
  }

• setup.js:

  var mysql = require('mysql');
  var config = require('./config');
  
  //初始化客户端
  delete config.database;
  var db = mysql.createClient(config);
  
  //创建数据库
  db.query('CREATE DATABASE IF NOT EXISTS `cart-example`');
  db.query('USE `cart-example`');
  
  //创建表
  db.query('DROP TABLE IF EXISTS item');
  db.query('CREATE TABLE item (' +
     'id INT(11) AUTO_INCREMENT,' +
     'title VARCHAR(255),' +
     'description TEXT,' +
     'created DATETIME,' +
     'PRIMARY KEY(id))'
  );
  db.query('DROP TABLE IF EXISTS review');
  db.query('CREATE TABLE review (' +
     'id INT(11) AUTO_INCREMENT,' +
     'item_id INT(11),' +
     'text TEXT,' +
     'stars INT(1),' +
     'created DATETIME,' +
     'PRIMARY KEY(id))'
  );
  
  //关闭客户端
  db.end(function() {
     process.exit();
  });
    

• server.js:

  var express = require('express');
  var mysql = require('mysql');
  var config = require('./config');
  
  app = express.createServer();
  
  app.use(express.bodyParser());
  app.set('view engine', 'jade');
  app.set('views','views');
  app.set('view options', {layout: false});
  
  //连接数据集
  var db = mysql.createClient(config);
  
  //首页路由
  app.get('/', function(req, res, next) {
  	db.query('SELECT id, title, description FROM item', function(err, results) {
  		res.render('index', {items: results});
  	});
  });
  //创建商品的路由
  app.post('/create', function(req, res, next) {
  	   //使用?避免字符串拼接，从而避免SQL注入攻击，但需要使用替换数据的第二参数
  	db.query('INSERT INTO item SET title = ?, description = ?',
  	[req.body.title, req.body.description], function(err, info) {
  		if(err) return next(err);
  		//通过info.insertId来创建商品的id
  		console.log('-item created with id %s', info.insertId);
  		res.redirect('/');
  	});
  });
  //查看商品路由
  app.get('/item/:id', function(req, res, next) {
  	function getItem (fn) {
  		db.query('SELECT id, title, description FROM item WHERE id= ? LIMIT 1',
  		[req.params.id], function (err, results) {
  			if(err) return next(err);
  			if(!results[0]) return res.send(404);
  			fn(results[0]);
  		});
  	}
  	function getReviews (item_id, fn) {
  		db.query('SELECT text, stars FROM review WHERE item_id= ?',
  			[item_id], function (err, results) {
  				if(err) return next(err);
  				fn(results);
  			});
  	}
  	getItem(function (item) {
  		getReviews(item.id, function (reviews) {
  			res.render('item', {item: item, reviews: reviews});
  		});
  	});
  });
  //评价商品的路由
  app.post('/item/:id/review', function(req, res, next) {
  	db.query('INSERT INTO review SET item_id = ?, stars = ?, text = ?',
  	[req.params.id, req.body.stars, req.body.text], function(err, info) {
  		if (err) return next(err);
  		console.log('-review created with id %s', info.insertId);
  		res.redirect('/item/' + req.params.id);
  	});
  });
  
  app.listen(3000, function() {
  	console.log(' - listeing on http://*:3000');
  });

• views/layout.jade:

  doctype 5
  html
    head
      title My shopping cart
    body
      h1 My shopping cart
      #cart
    block body

• views/index.jade:

  extends layout
  block body
    h2 All items
    if(items.length)
      ul
        each item in items
          li
            h3: a(href='/item/#{item.id}')=item.title
            =item.description
    else
      p No items to show
    h2 Create new item
  
    form(action='/create', method='post')
      p
        label Title
        input(type='text', name='title')
      p
        label Description
        textarea(name='description')
      p
        button Submit

• views/item.jade:

  extends layout
  block body
    a(href='/') Go back
    h2= item.title
    p= item.description
    h3 User reviews
    if(reviews.length)
      each review in reviews
        .review
          b #{review.stars} stars
          p= review.text
        hr
    else
      p No reviews to show. Write one!
  
    form(action='/item/#{item.id}/review', method='POST')
      fieldset
        legend Create review
        p
        label Stars
        select(name='stars')
            option 1
            option 2
            option 3
            option 4
            option 5
        p
          label Review
          textarea(name='text')
        p
          button(type='submit') Send
         

sequelize：

上面例子的问题：建表的过程是手动的；表的定义不是项目一部分（单独的setup.js），应用程序无法进行校验；

sequelize通过定义schema和模型同时使用同步特性来创建数据库表（不需要单独建立）；

• 连接sequelzie:

  var Sequelize = require('sequelize');
  var sequelize = new Sequelize('todo-example', 'root');

Sequelize构造器接受参数包括：

• • database(String)
  • username(String) //必要
  • password(String) //可选
  • other option(Object) //可选
  • host(String)
  • port(Number)

• 定义模型和同步：使用sequelize.define方法，第一参数为模型名，第二参数是包含了属性的对象；

  var Project = sequelize.define('Project', {
  	title : Sequelize.STRING,
  	description: Sequelize.TEXT,
  	created: Sequelize.DATE
  });
  

  对应的MySql类型：

  • Sequelize.STRING             //VARCHAR(255)
  • Sequelize.BOOLEAN          //TINYINT(1)
  • Sequelize.TEXT                //TEXT
  • Sequelize.DATE               //DATETIME
  • Sequelize.INTEGER          //INT

此外还可以传递选项对象： title: {type: Sequelize.STRING, default: 'title'}

• 例子：//注意要先建好数据库 建立数据库
• server.js

  var express = require('express');
  var Sequelize = require('sequelize');
  
  app = express.createServer();
  
  //注意格式
  app.use(express.static(__dirname + '/public'));
  app.use(express.bodyParser());
  
  app.set('view engine', 'jade');
  app.set('views','views');
  app.set('view option', {layout: false});
  
  //首页路由
  app.get('/', function (req, res, next) {
  	Project.findAll()
  	.success( function (projects) {
  		res.render('index', {projects: projects});
  	})
  	.error(next);
  });
  //删除项目路由
  app.del('/project/:id', function (req, res, next) {
  	Project.find(Number(req.params.id)).success(function (proj) {
  		proj.destroy()
  		.success(function () {
  			res.rend(200);
  		})
  		.error(next);
  	}).error(next);
  });
  //创建项目路由
  app.post('/projects', function (req, res, next) {
  	Project.build(req.body).save()
  	.success(function (obj) {
  		res.send(obj);
  	})
  	.error(next);
  });
  //展示指定项目路由
  app.get('/project/:id/tasks', function (req, res, next) {
  	Project.find(Number(req.params.id))
  	.success(function (project) {
  		project.getTasks().on('success', function (tasks) {
  			res.render('tasks', {project: project, tasks: tasks});
  		})
  	})
  	.error(next);
  
  });
  //为指定项目添加任务
  app.post('/project/:id/tasks', function (req, res, next) {
  	res.body.ProjectId = req.params.id;
  	Task.build(req.body).save()
  	.success(function (obj) {
  		res.send(obj);
  	})
  	.error(next);
  });
  //删除任务路由
  app.del('/task/:id', function (req, res, next) {
  	Task.find(Number(req.params.id)).success(function (task) {
  		task.destroy()
  		.success(function () {
  			res.send(200);
  		})
  		.error(err);
  	}).error(next);
  });
  
  app.listen(3000, function() {
  	console.log(' - listening on http://*3000');
  });
  
  //初始化，处于对结构清晰的考虑，在应用设置后做;
  var sequelize = new Sequelize('todo-example', 'root','123');
  
  //定义任务模型
  var Project = sequelize.define('Project', {
  	title: Sequelize.STRING,
  	description: Sequelize.TEXT,
  	created: Sequelize.DATE
  })
  
  var Task = sequelize.define('Task', {
  	title: Sequelize.STRING
  });
  
  //设置联合
  Task.belongsTo(Project);
  Project.hasMany(Task);
  
  //同步
  sequelize.sync();

• views/layout.jade

  doctype 5
  html
    head
      title TODO list app
      script(src='/lib/jquery.min.js')
      script(src='/main.js')
    body
      h1 TODO list app
      #todo
        block body
          

• views/index.jade

  extends layout
  block body
    h2 All items
    if(items.length)
      ul
        each item in items
          li
            h3: a(href='/item/#{item.id}')=item.title
            =item.description
    else
      p No items to show
    h2 Create new item
  
    form(action='/create', method='post')
      p
        label Title
        input(type='text', name='title')
      p
        label Description
        textarea(name='description')
      p
        button Submit

• views/tasks.jade

  h2 Tasks for project #{project.title}
  
  #list
    ul#tasks-list
      each task in tasks
        li
          span= task.title
          a.delete(href='/task/#{task.id}') X
  
    form#add(action='/project/#{project.id}/tasks', method='POST')
      input(type= 'text', name= 'title')
      button Add

• public.main.js

  $(function () {
  	$('form').submit( function (ev) {
  		ev.preventDefault();
  		var form = $(this);
  		$.ajax({
  			url: form.attr('action'),
  			type: 'POST',
  			data: form.serialize(),
  			success: function (obj) {
  				var el = $('<li>');
  				if ($('#projects-list').length) {
  					el.append($('<a>').attr('href', '/project/' + obj.id + '/tasks').text(obj.title + ' '))
  					  .append($('<a>').attr('href', '/project/' + obj.id).attr('class', 'delete').text('x'));
  				}
  				$('ul').append(el);
  			}
  		});
  		form.find('input').val(''); //clear input
  		$('ul').delegate('a.delete', 'click', function (ev) {
  			ev.preventDefault();
  			var li = $(this).closest('li');
  			$.ajac({
  				url: $(this).attr('href'),
  				type: 'DELETE',
  				SUCCESS: function () {
  					li.remove();
  				}
  			})
  		})
  	});
  
  });