1-使用 koa 搭建服务器
1.新建site文件夹，cmd进入命令行
npm init //初始化一份package.json
2.下载koa
npm install koa --save-dev
3.创建一个应用程序 新建app.js
const Koa = require('koa');
const app = new Koa();
app.use(async ctx => {
// ctx.body 即服务端响应的数据
ctx.body = 'Hello Koa';
})
// 监听端口、启动程序
app.listen(3000, err => {
if (err) throw err;
console.log('runing...');
})
4.启动
node app.js
2-如何配置 koa 路由
var koa=require('koa') var app=new koa() var Router=require('koa-router') var router=Router() router.use('/',(ctx)=>{ ctx.body='koa' }) app.use(router.routes()) .use(router.allowedMethods()) app.listen(3000,()=>{ console.log('服务器已启动，端口正在监听...') })3-静态资源如何获取
var koa=require('koa')
var app=new koa() var Router=require('koa-router') var router=Router() var path=require('path') var static=require('koa-static') app.use(static(path.join(__dirname,'public'))) router.use('/',(ctx)=>{ ctx.body='koa' }) app.use(router.routes()) .use(router.allowedMethods()) app.listen(3000,()=>{ console.log('服务器已启动，端口正在监听...') })
4-koa 如何使用模板引擎
var koa=require('koa')
var app=new koa() var Router=require('koa-router') var router=Router() var path=require('path') var static=require('koa-static') app.use(static(path.join(__dirname,'public'))) var render=require('koa-art-template') render('app',{ root:path.join(__dirname,'views'), extname:'.html', debug:procress.env.NODE_ENV!=='productions' }) router.use('/',async(ctx)=>{ await ctx.render('apps',{ name:'张三' }) }) app.use(router.routes()) .use(router.allowedMethods()) app.listen(3000,()=>{ console.log('服务器已启动，端口正在监听...') })
5-使用 koa 实现一个用户增删改查的案
1. app.js
app.js为入口文件，功能是连接数据库，导入文件，引入koa组件，最后启动服务。
'use strict';
const fs = require('fs');
const path = require('path');
const mongoose = require('mongoose');
const db = 'mongodb://localhost/test';
/* 连接数据库 */
mongoose.Promise = require('bluebird');
mongoose.connect(db, {useMongoClient: true});
/**
* 获取数据库表对应的js对象所在的路径
* @type {[type]}
*/
const models_path = path.join(__dirname, '/app/models');
/**
* 已递归的形式，读取models文件夹下的js模型文件，并require
* @param {[type]} modelPath [description]
* @return {[type]} [description]
*/
let walk = function (modelPath) {
fs.readdirSync(modelPath).forEach(function (file) {
let filePath = path.join(modelPath, '/' + file)
let stat = fs.statSync(filePath)
if (stat.isFile()) {
if (/(.*)\.(js|coffee)/.test(file)) {
require(filePath)
}
}
else if (stat.isDirectory()) {
walk(filePath)
}
})
};
walk(models_path);
require('babel-register');
const Koa = require('koa');
const logger = require('koa-logger');
const session = require('koa-session');
const bodyParser = require('koa-bodyparser');
const app = new Koa();
app.use(logger());
app.use(session(app));
app.use(bodyParser());
/**
* 使用路由转发请求
* @type {[type]}
*/
const router = require('./config/router')();
app.use(router.routes());
app.use(router.allowedMethods());
app.listen(3000);
console.log('app started at port 3000...');
2. 路由配置
路由配置在config/router.js中进行。
const Router = require('koa-router');
const User = require('../app/controllers/user');
module.exports = function () {
let router = new Router({
prefix: '/api'
});
router.post('/test/user/users', User.users);
router.post('/test/user/user', User.user);
router.post('/test/user/add', User.addUser);
router.post('/test/user/delete', User.deleteUser);
return router
};
post方法第一参数为路由地址，第二参数为路由地址对应的方法。
3. 表结构定义
表结构定义在app/models/user.js中。
let mongoose = require('mongoose');
let Schema = mongoose.Schema;
// 定义表结构
let UserSchema = new Schema({
name: {
type: String,
required: true
},
sex: String,
area: String,
always: Boolean,
relationship: Array,
mobile: String,
phone: String,
desc: String,
id: String
});
// 参数User 数据库中的集合名称, 不存在会创建.
let User = mongoose.model('User', UserSchema);
module.exports = User;
4. 工具方法
一些增删改查的工具方法放在app/dbhelp/userHelp.js中
'use strict';
let mongoose = require('mongoose');
let User = mongoose.model('User');
/* 查找用户 */
exports.findAllUsers = async () => {
let query = User.find();
let res = [];
await query.exec(function (err, users) {
if (err) {
res = [];
} else {
res = users;
}
});
return res
};
/* 查找特定用户 */
exports.findFilterUsers = async (params) => {
let nameReg = new RegExp(params.name, 'i');
let query = User.find({
name: {
$regex: nameReg
}
});
let res = [];
await query.exec(function (err, users) {
if (err) {
res = []
} else {
res = users;
}
});
return res
};
/* 查找单个用户 */
exports.findUser = async (params) => {
let query = User.find({
id: params.id
});
let res = {};
await query.exec(function (err, tUser) {
if (err) {
res = '没有该用户';
} else {
res = tUser[0];
}
});
return res
};
/* 新增用户 */
exports.addUser = async (user) => {
user = await user.save();
return user
};
/* 编辑用户 */
exports.updateUser = async (user) => {
user = await User.update({id: user.id}, {
$set: {
name: user.name,
sex: user.sex,
area: user.area,
always: user.always,
relationship: user.relationship,
phone: user.phone,
mobile: user.mobile,
desc: user.desc
}
});
return user
};
/* 删除用户 */
exports.deleteUser = async ({id}) => {
let flag = false;
console.log('flag==========>' + flag);
await User.remove({id}, function (err) {
if (err) {
flag = false
} else {
flag = true
}
});
console.log('flag=====await=====>' + flag);
return flag
};
5. 路由配置中对应的方法
路由配置中对应的方法在app/controller/user.js中。
'use strict';
let xss = require('xss');
let mongoose = require('mongoose');
let User = mongoose.model('User');
let uuid = require('uuid');
import userHelper from '../dbhelper/userHelper.js'
/* 多用户 */
exports.users = async (ctx, next) => {
let data;
if (ctx.request.body) {
data = await userHelper.findFilterUsers(ctx.request.body)
} else {
data = await userHelper.findAllUsers()
}
ctx.body = {
success: true,
data
}
};
/* 单用户 */
exports.user = async (ctx, next) => {
let data = await userHelper.findUser(ctx.request.body)
ctx.body = {
success: true,
data
}
};
/* 添加(更新)用户 */
exports.addUser = async (ctx, next) => {
let newObj = ctx.request.body,
user2;
let id = newObj.id || uuid.v4();
let user = new User({
name: newObj.name,
sex: newObj.sex,
area: newObj.area,
always: newObj.always,
relationship: newObj.relationship,
phone: newObj.phone,
mobile: newObj.mobile,
desc: newObj.desc,
id: id
});
if (newObj.id) {
user2 = await userHelper.updateUser(user);
} else {
user2 = await userHelper.addUser(user);
}
if (user2) {
ctx.body = {
success: true,
data: user2
}
}
};
/* 删除用户 */
exports.deleteUser = async (ctx, next) => {
let id = xss(ctx.request.body.id);
let data = await userHelper.deleteUser({id});
ctx.body = {
success: true,
data
}
};