目录
01-nodejs介绍
1.什么是nodejs
1.（javascript跑在机器端，服务端）Javascript on the machine
2.（跑在谷歌v8引擎上）A runtime for Google Chrome's V8 Javascript engine
2.nodejs的使用
1.构建工具（gulp，webpack都要依赖nodejs）Build Tools and Utilities
2.（web应用，web服务端）Web Applications / Web Services
3.nodejs擅长做什么
1.轻量级到大型应用 Lightweight Applications all the way up to very large
2.高并发性 High Concurrency
3.异步 Asyncronous Actions/Requests/non-blocking
4.实时 Realtime Communication
5.同构应用Isomorphic Applications - shared code between server and client
02rounning-files
1.安装
app.js
'use strict';
//process.argv 接受变量
var command = process.argv[2];
var a = Number(process.argv[3]);
var b = Number(process.argv[4]);
if (command === 'add') {
console.log(a+b);
} else if (command === 'sub'){
console.log(a-b);
} else if (command === 'mul'){
console.log(a*b);
}
CMD运行
node app.js add 1 2 //3
node app.js sub 1 2 //-1
node app.js mul 1 2 //2
03-commonjs-moudules
1.首先建一个math.js
exports.add = function(a, b){
return a + b;
}
exports.sub = function(a, b){
return a - b;
}
exports.mul = function(a, b){
return a * b;
}
2.然后建一个app.js 引人math.js
var math = require('./math');
console.log(math);//{ add: [Function], sub: [Function], mul: [Function] }
var command = process.argv[2];
var a = Number(process.argv[3]);
var b = Number([process.argv[4]]);
var value = math[command](a, b);
console.log(value);//node app.js mul 1 2 结果为2
04-npm-moudulers
建立package.json
npm init
下载包
npm install axios
npm install lodash
下载包，并加到package里面
npm install axios -S
npm install lodash -S
axios使用介绍传送门
lodash使用介绍传送门
建app.js
var _ = require('lodash');
var axios = require('axios');
axios.get('http://rest.learncode.academy/api/myuser/friends').then((res) => {
console.log(res.data);
var jake = _.find(res.data, {name: "Jake"});
console.log(jake);//{ name: 'Jake', age: '32', id: '57766a9a4a9cb90100bf16ec' }
})
05-npm script
简单介绍
scripts里面的
"start": "node app"
npm run start 相当于 node app
{
"name": "5-npm-scripts",
"version": "1.0.0",
"description": "",
"main": "app.js",
"dependencies": {},
"devDependencies": {
"nodemon": "^1.9.2"
},
"scripts": {
"start": "node app",
"dev": "nodemon app",
"test": "node test",
"test-watch": "nodemon test"
},
"author": "",
"license": "ISC"
}
更加详细的介绍，建议看阮一峰的scripts介绍
nodemon
这个可以监控js变化
eg
app.js
'use strict';
var math = require('./math');
var value = math.add(5, 6);
console.log(value);
math.js
exports.add = function(a, b) {
return a + b;
}
exports.subtract = function(a, b) {
return a - b;
}
exports.multiply = function(a, b) {
return a * b;
}
test.js
'use strict';
var assert = require('assert');
var math = require('./math');
assert(math.add(3, 4) === 7);
assert(math.subtract(3, 4) === -1);
assert(math.multiply(3, 4) === 12);
console.log("all tests passed!");
06-base-webserver
创建server.js
'use strict';
//http模块
var http = require('http');
//封装的方法
var handlers = require('./handlers');
//创建服务
var server = http.createServer(function(request, response) {
//url地址
var url = request.url;
if(url === '/'){
handlers.homepage(request, response);
}else if (url === "/profile") {
handlers.profile(request, response);
} else {
handlers.notFound(request, response);
}
});
//端口3000
server.listen(3000);
console.log('start 3000');
handlers.js
'use strict';
//首页
exports.homepage = function(request, response){
response.setHeader('Content-Type', 'text/html');
response.end('<h1>helloworld</h1>')
}
//一个接口
exports.profile = function(request, response){
var profile = {
name : 'will',
age : 35
}
response.setHeader('Content-Type','application/json');
response.end(JSON.stringify(profile));
}
//404
exports.notFound = function(request, response) {
response.statusCode = 404;
response.setHeader("Content-Type", "text/html");
response.end("<h1>404 Not Found!</h1>");
}
07-es6
1.下载babel-register
npm install babel-register -S
2.下载babel-preset-es2015
npm install babel-preset-es2015 --save-dev
main.js
require('babel-register');
require('./src/server');
server.js
import http from 'http';
import { homepage, notFound } from './handlers';
const server = http.createServer((request, response) =>{
homepage(request, response);
});
server.listen(3000);
console.log('listen 3000');
handlers.js
export function homepage(request, response){
response.setHeader("Content-Type", "text/html");
response.end("hello world");
}
export function notFound(request, response){
response.setHeader("Content-Type", "text/html");
response.end("404");
}
08-express
express 简单介绍
下载express
npm install express -S
简单的例子
const express = require('express');
//引入express
const app = express();
//链式结构，中间件，必须要有next才能执行下一步
app
.use((req, res, next) => {
var profile = {name: "will"};
req.profile = profile;
next();
})
.get("/", (req, res) => {
res.send(req.profile);
})
//监听端口3000
app.listen(3000);
console.log('listen 3000');
09-routes的使用
新建一个users.js,然后app.use使用这个中间件
const users = require('./routes/users');
app.use('/users', users);
users.js
const express = require('express');
const router = express.Router();
router
.get("/", (req, res) => {
res.send(users);
})
.get("/:id", (req, res) => {
const { id } = req.params;
const user = users.find(user => user.id == id)
if (user) {
res.send(user);
} else {
res.status(404).send(`User ${id} does not exist`);
}
})
.delete('/:id', (req, res) => {
const { id } = req.params;
const index = users.findIndex(user => user.id == id);
if (index > -1){
users.splice(index, 1);
res.sendStatus(200);
} else {
res.status(404).send(`User ${id} does not exist`);
}
});
module.exports = router;
var users = [{
"id": 1,
"first_name": "Gregory",
"last_name": "Garcia",
"email": "ggarcia0@list-manage.com",
"gender": "Male",
"ip_address": "23.180.99.244"
}]
10-static静态文件
下载serve-favicon
npm install serve-favicon -S
静态文件
const staticAssets = __dirname + '/public';
ico地址
const favicon = require('serve-favicon');
const faviconPath = __dirname + '/public/favicon.ico';
使用
app
.use(express.static(staticAssets))
.use(favicon(faviconPath))
完整代码
const express = require('express');
const favicon = require('serve-favicon');
const app = express();
//静态文件
const staticAssets = __dirname + '/public';
//ico地址
const faviconPath = __dirname + '/public/favicon.ico';
app
.use(express.static(staticAssets))
.use(favicon(faviconPath))
.get('/api/profile', (req, res) => {
var profile = {name: 'will'};
res.send(profile);
});
app.listen(3000);
11-hjs模板引入
下载hjs
npm install hjs -S
express中引入
app
.set("views", __dirname + "/views")
.set('view engine', 'hjs')
渲染
var title = "still another title";
var tweets = [
"my first tweet",
"other tweet",
"yet another tweet",
];
res.render('index', {
title: title,
tweets: tweets,
showTweets: true,
//模板替換，公用的
partials: {header: "header", tweets: "tweets"}
})
views/header.hjs
<h1>title</h1>
views/tweets.hjs
<ul>
{{#tweets}}
<li>{{.}}</li>
{{/tweets}}
</ul>
views/index.hjs
<html>
<head>
<link rel="stylesheet" href="/css/main.css">
</head>
<body>
{{> header}}
{{#showTweets}}
{{> tweets}}
{{/showTweets}}
<script src="/js/main.js"></script>
</body>
</html>
server.js完整代码
'use strict';
const express = require('express');
const favicon = require('serve-favicon');
const app = express();
const staticAssets = __dirname + '/public';
//const faviconPath = __dirname + '/public/favicon.ico';
app
.set("views", __dirname + "/views")
.set('view engine', 'hjs')
.use(express.static(staticAssets))
//.use(favicon(faviconPath))
.get('/', (req, res) => {
var title = "still another title";
var tweets = [
"my first tweet",
"other tweet",
"yet another tweet",
];
res.render('index', {
title: title,
tweets: tweets,
showTweets: true,
//模板替換，公用的
partials: {header: "header", tweets: "tweets"}
})
});
app.listen(3000);
console.log('listen 3000');
12-mysql
连接mysql数据库，终于到了这步。
mysql 下载
npm install mysql -S
knex下載 knex传送门
npm install knex -S
链接mysql
const db = knex({
client: 'mysql',
connection: {
host: '127.0.0.1',
user: 'root',
database: 'test_node',
password: 'youpassword'
}
})
完整代码(这里是用RESTful）
const express = require('express');
const bodyParser = require('body-parser');
const knex = require('knex');
const db = knex({
client: 'mysql',
connection: {
host: '127.0.0.1',
user: 'root',
database: 'test_node',
password: 'youpassword'
}
})
// GET /users 获取所有用户
// GET /user/:id 获取id
// POST /users 创建用户
// PUT /users/:id 更新用户
// DELETE /users/:id 删除用户
express()
.use(bodyParser.json())
.get('/users', (req, res, next) => {
db('users').then((users) => {
res.send(users);
}, next)
})
.post('/users', (req, res, next) => {
db('users')
.insert(req.body)
.then((userIds) =>{
res.send(userIds)
}, next)
})
.get('/users/:id', (req, res, next) => {
const { id } = req.params;
db('users')
.where('id', id)
.first()
.then((users)=>{
if(!users){
return res.send(400);
}
res.send(users)
}, next)
})
.put('/users/:id', (req, res, next) => {
const { id } = req.params;
db('users')
.where('id', id)
.update(req.body)
.then((result) => {
if(result === 0){
return res.send(400)
}
res.send(200)
}, next)
})
.delete('/users/:id', (req, res, next) => {
const { id } = req.params;
db('users')
.where('id', id)
.delete()
.then((result) => {
if(result === 0){
return res.send(400)
}
res.send(200)
}, next)
})
.listen(3000)
console.log('listen 3000');