Translated By 林凌灵
翻译目的:练练手,同时了解别人的思维方式
原文地址:RESTful API With Node.js + MongoDB
12 Sep 2013
我是一名移动应用开发者,我需要某种后端服务用来频繁地处理用户数据到数据库中.当然,我可以使用后端即服务类的网站(Parse, Backendless, 等等…),(译者:国内比较出名的有Bmob).但自己解决总是更方便和实际的选择.
于是我决定去探索我完全未知的技术领域,那个现在非常流行,定位在容易让新人吸收,并且不需要过于深入了解和处理大型项目经验的项目.
本文将仔细介绍使用Node.js的Express.js框架结合操作MongoDB的Mongoose.js,来给移动APP来搭建一个rest api.对于访问限制,我们将使用 OAuth2orize 和 Passport.js 来实现 OAuth 2.0.
1. Node.js + Express.js, 简洁的 web-server
2. 错误处理
3. RESTful API 要点,增删改查
4. MongoDB & Mongoose.js
5. 访问限制 — OAuth 2.0, Passport.js
Node.js 没有i/o 阻塞,这对于需要被多个客户端访问的API服务来说是非常棒的.express.js 是一个先进的,轻量级的框架,它能帮助我们快速专注地编写我们需要API.
那么让我们用单个文件server.js来创建一个项目吧~因为我们的项目依赖于Express.js,所以我们将先安装它.安装第三方模块我们将使用Node的包管理器(NPM),很简单.只要在你的项目根目录下:npm install 模块名 .
app.get('/api/articles', function(req, res) {
res.send('This is not implemented now');
});
app.post('/api/articles', function(req, res) {
res.send('This is not implemented now');
});
app.get('/api/articles/:id', function(req, res) {
res.send('This is not implemented now');
});
app.put('/api/articles/:id', function (req, res){
res.send('This is not implemented now');
});
app.delete('/api/articles/:id', function (req, res){
res.send('This is not implemented now');
});
测试 post/put/delete 我推荐大家使用一个封装了curl 的强大库httpie,我将给出使用这个工具发起请求的例子.
选择一个数据库,我再次被我渴望新事物的心引导:MongoDB - 最流行的 NoSQL 文档型数据库.Mongoose.js-一层封装,帮助我们更加舒适地创建函数式schema文档.
下载并安装mongodb,然后安装Mongoose : npm install mongoose.我将把数据库交互作为独立的模块放在libs/mongoose.js.
var mongoose = require('mongoose');
var log = require('./log')(module);
mongoose.connect('mongodb://localhost/test1');
var db = mongoose.connection;
db.on('error', function (err) {
log.error('connection error:', err.message);
});
db.once('open', function callback () {
log.info("Connected to DB!");
});
var Schema = mongoose.Schema;
// Schemas
var Images = new Schema({
kind: {
type: String,
enum: ['thumbnail', 'detail'],
required: true
},
url: { type: String, required: true }
});
var Article = new Schema({
title: { type: String, required: true },
author: { type: String, required: true },
description: { type: String, required: true },
images: [Images],
modified: { type: Date, default: Date.now }
});
// validation
Article.path('title').validate(function (v) {
return v.length > 5 && v.length < 70;
});
var ArticleModel = mongoose.model('Article', Article);
module.exports.ArticleModel = ArticleModel;
在这个文件中,实现了数据库连接和对象模式定义.文章将包含图片对象.同时也实现了各种各样复杂的验证.
我将使用 nconf 模块 来储存数据库路径.同时,我们把服务器端口也移到这里.安装:npm i nconf .自定义封装将被放在 libs/config.js.
var nconf = require('nconf');
nconf.argv()
.env()
.file({ file: './config.json' });
module.exports = nconf;
All the settings will be stored in config.json at the project’s root.
{
"port" : 1337,
"mongoose": {
"uri": "mongodb://localhost/test1"
}
}
mongoose.js changes:
var config = require('./config');
mongoose.connect(config.get('mongoose:uri'));
server.js changes:
var config = require('./libs/config');
app.listen(config.get('port'), function(){
log.info('Express server listening on port ' + config.get('port'));
});
Let’s add CRUD actions in existing routes.
var ArticleModel = require('./libs/mongoose').ArticleModel;
app.get('/api/articles', function(req, res) {
return ArticleModel.find(function (err, articles) {
if (!err) {
return res.send(articles);
} else {
res.statusCode = 500;
log.error('Internal error(%d): %s',res.statusCode,err.message);
return res.send({ error: 'Server error' });
}
});
});
app.post('/api/articles', function(req, res) {
var article
= new ArticleModel({
title: req.body.title,
author: req.body.author,
description: req.body.description,
images: req.body.images
});
article.save(function (err) {
if (!err) {
log.info("article created");
return res.send({ status: 'OK', article:article });
} else {
console.log(err);
if(err.name == 'ValidationError') {
res.statusCode = 400;
res.send({ error: 'Validation error' });
} else {
res.statusCode = 500;
res.send({ error: 'Server error' });
}
log.error('Internal error(%d): %s',res.statusCode,err.message);
}
});
});
app.get('/api/articles/:id', function(req, res) {
return ArticleModel.findById(req.params.id, function (err, article) {
if(!article) {
res.statusCode = 404;
return res.send({ error: 'Not found' });
}
if (!err) {
return res.send({ status: 'OK', article:article });
} else {
res.statusCode = 500;
log.error('Internal error(%d): %s',res.statusCode,err.message);
return res.send({ error: 'Server error' });
}
});
});
app.put('/api/articles/:id', function (req, res){
return ArticleModel.findById(req.params.id, function (err, article) {
if(!article) {
res.statusCode = 404;
return res.send({ error: 'Not found' });
}
article.title = req.body.title;
article.description = req.body.description;
article.author = req.body.author;
article.images = req.body.images;
return article.save(function (err) {
if (!err) {
log.info("article updated");
return res.send({ status: 'OK', article:article });
} else {
if(err.name == 'ValidationError') {
res.statusCode = 400;
res.send({ error: 'Validation error' });
} else {
res.statusCode = 500;
res.send({ error: 'Server error' });
}
log.error('Internal error(%d): %s',res.statusCode,err.message);
}
});
});
});
app.delete('/api/articles/:id', function (req, res){
return ArticleModel.findById(req.params.id, function (err, article) {
if(!article) {
res.statusCode = 404;
return res.send({ error: 'Not found' });
}
return article.remove(function (err) {
if (!err) {
log.info("article removed");
return res.send({ status: 'OK' });
} else {
res.statusCode = 500;
log.error('Internal error(%d): %s',res.statusCode,err.message);
return res.send({ error: 'Server error' });
}
});
});
});
所以的操作都非常清晰了,感谢Mongoose 和 自解释模型.现在,在我们开始运行node.js 之前,我我们先运行mongodb 服务器:mongo-一个实用的客户端工具用于处理数据库.服务本身就是mongod自己.
使用httpie 发送请求的例子:
<code class="sh hljs" data-origin="" <pre><code="" post="" http:="" localhost:1337="" api="" articles="" title="TestArticle" author="John Doe" description="lorem ipsum dolar sit amet" images:="[{"kind":"thumbnail", "url":"http://habrahabr.ru/images/write-topic.png"}, {"kind":"detail", "url":"http://habrahabr.ru/images/write-topic.png"}]" "="" style="display: block;border: 1px solid rgb(204, 204, 204); white-space: pre; padding: 0.5em; margin: 0px;border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; word-break: break-all; word-wrap: break-word; border: 1px solid rgb(204, 204, 204); padding: 0px 5px; margin: 0px 2px;font-size: 0.9em; font-family: Consolas, Inconsolata, Courier, monospace;display: block; overflow-x: auto; padding: 0.5em; background-color: rgb(253, 246, 227); color: rgb(101, 123, 131); background-position: initial initial; background-repeat: initial initial;">http POST http://localhost:1337/api/articles title=TestArticle author='John Doe' description='lorem ipsum dolar sit amet' images:='[{"kind":"thumbnail", "url":"http://habrahabr.ru/images/write-topic.png"}, {"kind":"detail", "url":"http://habrahabr.ru/images/write-topic.png"}]' http http://localhost:1337/api/articles http http://localhost:1337/api/articles/52306b6a0df1064e9d000003 http PUT http://localhost:1337/api/articles/52306b6a0df1064e9d000003 title=TestArticle2 author='John Doe' description='lorem ipsum dolar sit amet' images:='[{"kind":"thumbnail", "url":"http://habrahabr.ru/images/write-topic.png"}, {"kind":"detail", "url":"http://habrahabr.ru/images/write-topic.png"}]' http DELETE http://localhost:1337/api/articles/52306b6a0df1064e9d000003
这个阶段,你可以从github检出本项目
我们将使用 OAuth2. 或许这是多余的,但在将来这种方法将促进与其他授权方法的集成.
Passport.js 模块将负责访问控制.对于OAuth2 服务器,我将使用与其同一个作者的 OAuth2orize ,访问令牌将被储存在MongoDB中.
首先你需要安装下面全部的模块:
Faker
oauth2orize
passport
passport-http
passport-http-bearer
passport-oauth2-client-password
然后,你需要加入 mongoose.js 这个schema 给 users 和 tokens:
var crypto = require('crypto');
// User
var User = new Schema({
username: {
type: String,
unique: true,
required: true
},
hashedPassword: {
type: String,
required: true
},
salt: {
type: String,
required: true
},
created: {
type: Date,
default: Date.now
}
});
User.methods.encryptPassword = function(password) {
return crypto.createHmac('sha1', this.salt).update(password).digest('hex');
//more secure – return crypto.pbkdf2Sync(password, this.salt, 10000, 512);
};
User.virtual('userId')
.get(function () {
return this.id;
});
User.virtual('password')
.set(function(password) {
this._plainPassword = password;
this.salt = crypto.randomBytes(32).toString('base64');
//more secure - this.salt = crypto.randomBytes(128).toString('base64');
this.hashedPassword = this.encryptPassword(password);
})
.get(function() { return this._plainPassword; });
User.methods.checkPassword = function(password) {
return this.encryptPassword(password) === this.hashedPassword;
};
var UserModel = mongoose.model('User', User);
// Client
var Client = new Schema({
name: {
type: String,
unique: true,
required: true
},
clientId: {
type: String,
unique: true,
required: true
},
clientSecret: {
type: String,
required: true
}
});
var ClientModel = mongoose.model('Client', Client);
// AccessToken
var AccessToken = new Schema({
userId: {
type: String,
required: true
},
clientId: {
type: String,
required: true
},
token: {
type: String,
unique: true,
required: true
},
created: {
type: Date,
default: Date.now
}
});
var AccessTokenModel = mongoose.model('AccessToken', AccessToken);
// RefreshToken
var RefreshToken = new Schema({
userId: {
type: String,
required: true
},
clientId: {
type: String,
required: true
},
token: {
type: String,
unique: true,
required: true
},
created: {
type: Date,
default: Date.now
}
});
var RefreshTokenModel = mongoose.model('RefreshToken', RefreshToken);
module.exports.UserModel = UserModel;
module.exports.ClientModel = ClientModel;
module.exports.AccessTokenModel = AccessTokenModel;
module.exports.RefreshTokenModel = RefreshTokenModel;
password虚拟属性举例了mongoose如何方便地在模型中嵌入逻辑.哈希算法和加盐(译者:加密加盐都是为了保护数据)不在本文的讨论范围,它的具体实现这里就不说了.
数据库对象:
User –一个用户有name,password以及相应的盐.
Client – 一个代表用户做出请求的客户端,需要具有name和secretcode.
AccessToken – token (即不记名类型), 颁发给客户端应用的, 具有时间限制(译者:就像cookie里的sessionid).
RefreshToken –另一种类型的token,允许你重新获得一个不记名的token而不需要通过密码获得.
在 config.json中配置token的生存时间:
{
"port" : 1337,
"security": {
"tokenLife" : 3600
},
"mongoose": {
"uri": "mongodb://localhost/testAPI"
}
}
我在独立的模块中实现了OAuth2 服务器 以及认证逻辑.在auth.js 和passport.js 中策略已经写好了.我们载入3个策略—两个是用于OAuth2的username-password流的,一个是用于检查token的.
var config = require('./config');
var passport = require('passport');
var BasicStrategy = require('passport-http').BasicStrategy;
var ClientPasswordStrategy = require('passport-oauth2-client-password').Strategy;
var BearerStrategy = require('passport-http-bearer').Strategy;
var UserModel = require('./mongoose').UserModel;
var ClientModel = require('./mongoose').ClientModel;
var AccessTokenModel = require('./mongoose').AccessTokenModel;
var RefreshTokenModel = require('./mongoose').RefreshTokenModel;
passport.use(new BasicStrategy(
function(username, password, done) {
ClientModel.findOne({ clientId: username }, function(err, client) {
if (err) { return done(err); }
if (!client) { return done(null, false); }
if (client.clientSecret != password) { return done(null, false); }
return done(null, client);
});
}
));
passport.use(new ClientPasswordStrategy(
function(clientId, clientSecret, done) {
ClientModel.findOne({ clientId: clientId }, function(err, client) {
if (err) { return done(err); }
if (!client) { return done(null, false); }
if (client.clientSecret != clientSecret) { return done(null, false); }
return done(null, client);
});
}
));
passport.use(new
BearerStrategy(
function(accessToken, done) {
AccessTokenModel.findOne({ token: accessToken }, function(err, token) {
if (err) { return done(err); }
if (!token) { return done(null, false); }
if( Math.round((Date.now()-token.created)/1000) > config.get('security:tokenLife') ) {
AccessTokenModel.remove({ token: accessToken }, function (err) {
if (err) return done(err);
});
return done(null, false, { message: 'Token expired' });
}
UserModel.findById(token.userId, function(err, user) {
if (err) { return done(err); }
if (!user) { return done(null, false, { message: 'Unknown user' }); }
var info = { scope: '*' }
done(null, user, info);
});
});
}
));
oauth2.js is responsible for the issuance and renewal of the token. One token exchange strategy is for username-password flow, another is to refresh tokens.
oauth2.js 负责颁发和更新token.其中一个token交互策略是给username-password 流的,另一个是用于刷新token的.
var oauth2orize = require('oauth2orize');
var passport = require('passport');
var crypto = require('crypto');
var config = require('./config');
var UserModel = require('./mongoose').UserModel;
var ClientModel = require('./mongoose').ClientModel;
var AccessTokenModel = require('./mongoose').AccessTokenModel;
var RefreshTokenModel = require('./mongoose').RefreshTokenModel;
// create OAuth 2.0 server
var server = oauth2orize.createServer();
// Exchange username & password for access token.
server.exchange(oauth2orize.exchange.password(function(client, username, password, scope, done) {
UserModel.findOne({ username: username }, function(err, user) {
if (err) { return done(err); }
if (!user) { return done(null, false); }
if (!user.checkPassword(password)) { return done(null, false); }
RefreshTokenModel.remove({ userId: user.userId, clientId: client.clientId }, function (err) {
if (err) return done(err);
});
AccessTokenModel.remove({ userId: user.userId, clientId: client.clientId }, function (err) {
if (err) return done(err);
});
var tokenValue = crypto.randomBytes(32).toString('base64');
var refreshTokenValue = crypto.randomBytes(32).toString('base64');
var token = new AccessTokenModel({ token: tokenValue, clientId: client.clientId, userId: user.userId });
var refreshToken = new RefreshTokenModel({ token: refreshTokenValue, clientId: client.clientId, userId: user.userId });
refreshToken.save(function (err) {
if (err) { return done(err); }
});
var info = { scope: '*' }
token.save(function (err, token) {
if (err) { return done(err); }
done(null, tokenValue, refreshTokenValue, { 'expires_in': config.get('security:tokenLife') });
});
});
}));
// Exchange refreshToken for access token.
server.exchange(oauth2orize.exchange.refreshToken(function(client, refreshToken, scope, done) {
RefreshTokenModel.findOne({ token: refreshToken }, function(err, token) {
if (err) { return done(err); }
if (!token) { return done(null, false); }
if (!token) { return done(null, false); }
UserModel.findById(token.userId, function(err, user) {
if (err) { return done(err); }
if (!user) { return done(null, false); }
RefreshTokenModel.remove({ userId: user.userId, clientId: client.clientId }, function (err) {
if (err) return done(err);
});
AccessTokenModel.remove({ userId: user.userId, clientId: client.clientId }, function (err) {
if (err) return done(err);
});
var tokenValue = crypto.randomBytes(32).toString('base64');
var refreshTokenValue = crypto.randomBytes(32).toString('base64');
var token = new AccessTokenModel({ token: tokenValue, clientId: client.clientId, userId: user.userId });
var refreshToken = new RefreshTokenModel({ token: refreshTokenValue, clientId: client.clientId, userId: user.userId });
refreshToken.save(function (err) {
if (err) { return done(err); }
});
var info = { scope: '*' }
token.save(function (err, token) {
if (err) { return done(err); }
done(null, tokenValue, refreshTokenValue, { 'expires_in': config.get('security:tokenLife') });
});
});
});
}));
// token endpoint
exports.token = [
passport.authenticate(['basic', 'oauth2-client-password'], { session: false }),
server.token(),
server.errorHandler()
]
在server.js加载这个模块:
var oauth2 = require('./libs/oauth2');
app.use(passport.initialize());
require('./libs/auth');
app.post('/oauth/token', oauth2.token);
app.get('/api/userInfo',
passport.authenticate('bearer', { session: false }),
function(req, res) {
// req.authInfo is set using the `info` argument supplied by
// `BearerStrategy`. It is typically used to indicate scope of the token,
// and used in access control checks. For illustrative purposes, this
// example simply returns the scope in the response.
res.json({ user_id: req.user.userId, name: req.user.username, scope: req.authInfo.scope })
}
);
例如,限制访问localhost:1337/api/userInfo.
To check the auth logic we should create a user and a client in our database. Use this node application, which will create the necessary objects and remove redundant from collections. It helps quickly clean the tokens and users for testing.
这个检查逻辑,我们需要在数据库创建一个user和client.我们将使用node程序来创建必要的对象和移除冗余的集合.这可以帮助我们在测试时迅速地清空token
var log = require('./libs/log')(module);
var mongoose = require('./libs/mongoose').mongoose;
var UserModel = require('./libs/mongoose').UserModel;
var ClientModel = require('./libs/mongoose').ClientModel;
var AccessTokenModel = require('./libs/mongoose').AccessTokenModel;
var RefreshTokenModel = require('./libs/mongoose').RefreshTokenModel;
var faker = require('Faker');
UserModel.remove({}, function(err) {
var user = new UserModel({ username: "andrey", password: "simplepassword" });
user.save(function(err, user) {
if(err) return log.error(err);
else log.info("New user - %s:%s",user.username,user.password);
});
for(i=0; i<4; i++) {
var user = new UserModel({ username: faker.random.first_name().toLowerCase(), password: faker.Lorem.words(1)[0] });
user.save(function(err, user) {
if(err) return log.error(err);
else log.info("New user - %s:%s",user.username,user.password);
});
}
});
ClientModel.remove({}, function(err) {
var client = new ClientModel({ name: "OurService iOS client v1", clientId: "mobileV1", clientSecret:"abc123456" });
client.save(function(err, client) {
if(err) return log.error(err);
else log.info("New client - %s:%s",client.clientId,client.clientSecret);
});
});
AccessTokenModel.remove({}, function (err) {
if (err) return log.error(err);
});
RefreshTokenModel.remove({}, function (err) {
if (err) return log.error(err);
});
setTimeout(function() {
mongoose.disconnect();
}, 3000);
如果你使用dataGgen.js,用一下命令测试授权将适合你.这里我们再次看看httpie的使用.
http POST http://localhost:1337/oauth/token grant_type=password client_id=mobileV1 client_secret=abc123456 username=andrey password=simplepassword
http POST http://localhost:1337/oauth/token grant_type=refresh_token client_id=mobileV1 client_secret=abc123456 refresh_token=TOKEN
http http://localhost:1337/api/userinfo Authorization:'Bearer TOKEN'
注意!在生产环境尽量使用HTTPS,这是OAuth2的隐含内容.还有,不要不忘记对密码进行正确的哈希处理.重申一下,你可在github找到这个项目.
开启本例前,你要先运行 npm install在你项目的根目录,然后运行mongod,node dataGen.js (等待它完成),然后运行node server.js.
如果有哪个部分有需要更清楚地描述,请给我留言.
总而言之,我想说node.js是一个伟大的、方便的服务器解决方案。MongoDB面向文档的方法是一个很不同寻常的但又确实是一个有用的工具。它还有很多功能我还不习惯。nodejs有一个很大的社区,有很多开源项目。例如,oauth2orize和password.js就是Jared Hanson带来精彩的项目,这很好地促进了项目的实现。
Evgeny Aleksandrov
iOS developer
evgeny@aleksandrov.ws
github.com/ealeksandrov
twitter.com/ealeksandrov