python web框架简介Bottle Flask Tornado

2022-10-18 11:05:20

Bottle

Bottle是一个快速、简洁、轻量级的基于WSIG的微型Web框架，此框架只由一个 .py 文件，除了Python的标准库外，其不依赖任何其他模块。

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pip install bottle
easy_install bottle
apt-get install python-bottle
wget http://bottlepy.org/bottle.py

Bottle框架大致可以分为以下部分：

  • 路由系统，将不同请求交由指定函数处理
  • 模板系统，将模板中的特殊语法渲染成字符串，值得一说的是Bottle的模板引擎可以任意指定：Bottle内置模板、mako、jinja2、cheetah
  • 公共组件，用于提供处理请求相关的信息，如：表单数据、cookies、请求头等
  • 服务，Bottle默认支持多种基于WSGI的服务，如：
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    server_names = {
        'cgi': CGIServer,
        'flup': FlupFCGIServer,
        'wsgiref': WSGIRefServer,
        'waitress': WaitressServer,
        'cherrypy': CherryPyServer,
        'paste': PasteServer,
        'fapws3': FapwsServer,
        'tornado': TornadoServer,
        'gae': AppEngineServer,
        'twisted': TwistedServer,
        'diesel': DieselServer,
        'meinheld': MeinheldServer,
        'gunicorn': GunicornServer,
        'eventlet': EventletServer,
        'gevent': GeventServer,
        'geventSocketIO':GeventSocketIOServer,
        'rocket': RocketServer,
        'bjoern' : BjoernServer,
        'auto': AutoServer,
    }

框架的基本使用

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from bottle import template, Bottle
root = Bottle()
 
@root.route('/hello/')
def index():
    return "Hello World"
    # return template('<b>Hello {{name}}</b>!', name="Alex")
 
root.run(host='localhost', port=8080)

一、路由系统

路由系统是的url对应指定函数，当用户请求某个url时，就由指定函数处理当前请求，对于Bottle的路由系统可以分为一下几类：

  • 静态路由
  • 动态路由
  • 请求方法路由
  • 二级路由

1、静态路由

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@root.route('/hello/')
def index():
    return template('<b>Hello {{name}}</b>!', name="Alex")

2、动态路由

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@root.route('/wiki/<pagename>')
def callback(pagename):
    ...
 
@root.route('/object/<id:int>')
def callback(id):
    ...
 
@root.route('/show/<name:re:[a-z]+>')
def callback(name):
    ...
 
@root.route('/static/<path:path>')
def callback(path):
    return static_file(path, root='static')

3、请求方法路由

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@root.route('/hello/', method='POST')
def index():
    ...
 
@root.get('/hello/')
def index():
    ...
 
@root.post('/hello/')
def index():
    ...
 
@root.put('/hello/')
def index():
    ...
 
@root.delete('/hello/')
def index():
    ...

4、二级路由

#!/usr/bin/env python

# -*- coding:utf-8 -*-

from bottle import template, Bottle

app01 = Bottle()

@app01.route('/hello/', method='GET')

def index():

    return template('<b>App01</b>!')

app01.py

#!/usr/bin/env python

# -*- coding:utf-8 -*-

from bottle import template, Bottle

app02 = Bottle()

@app02.route('/hello/', method='GET')

def index():

    return template('<b>App02</b>!')

app02.py

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from bottle import template, Bottle
from bottle import static_file
root = Bottle()
 
@root.route('/hello/')
def index():
    return template('<b>Root {{name}}</b>!', name="Alex")
 
from framwork_bottle import app01
from framwork_bottle import app02
 
root.mount('app01', app01.app01)
root.mount('app02', app02.app02)
 
root.run(host='localhost', port=8080)

二、模板系统

模板系统用于将Html和自定的值两者进行渲染，从而得到字符串，然后将该字符串返回给客户端。我们知道在Bottle中可以使用 内置模板系统、mako、jinja2、cheetah等，以内置模板系统为例：

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

</head>

<body>

    <h1>{{name}}</h1>

</body>

</html>

hello_template.tpl

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from bottle import template, Bottle
root = Bottle()
 
@root.route('/hello/')
def index():
    # 默认情况下去目录：['./', './views/']中寻找模板文件 hello_template.html
    # 配置在 bottle.TEMPLATE_PATH 中
    return template('hello_template.tpl', name='alex')
 
root.run(host='localhost', port=8080)

1、语法

  • 单值
  • 单行Python代码
  • Python代码快
  • Python、Html混合
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<h1>1、单值</h1>
{{name}}
 
<h1>2、单行Python代码</h1>
% s1 = "hello"
 
 
<h1>3、Python代码块</h1>
<%
    # A block of python code
    name = name.title().strip()
    if name == "Alex":
        name="seven"
%>
 
 
<h1>4、Python、Html混合</h1>
 
% if True:
    <span>{{name}}</span>
% end
<ul>
  % for item in name:
    <li>{{item}}</li>
  % end
</ul>

2、函数

include(sub_template, **variables)

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# 导入其他模板文件
 
% include('header.tpl', title='Page Title')
Page Content
% include('footer.tpl')

rebase(name, **variables)

<html>

<head>

  <title>{{title or 'No title'}}</title>

</head>

<body>

  {{!base}}

</body>

</html>

base.tpl

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# 导入母版
 
% rebase('base.tpl', title='Page Title')
<p>Page Content ...</p>

defined(name)

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# 检查当前变量是否已经被定义，已定义True，未定义False

get(name, default=None)

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# 获取某个变量的值，不存在时可设置默认值

setdefault(name, default)

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# 如果变量不存在时，为变量设置默认值

扩展：自定义函数

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

</head>

<body>

    <h1>自定义函数</h1>

    {{ wupeiqi() }}

</body>

</html>

hello_template.tpl

#!/usr/bin/env python

# -*- coding:utf-8 -*-

from bottle import template, Bottle,SimpleTemplate

root = Bottle()

def custom():

    return ''

@root.route('/hello/')

def index():

    # 默认情况下去目录：['./', './views/']中寻找模板文件 hello_template.html

    # 配置在 bottle.TEMPLATE_PATH 中

    return template('hello_template.html', name='alex', wupeiqi=custom)

root.run(host='localhost', port=8080)

main.py

注：变量或函数前添加 【 ! 】，则会关闭转义的功能

三、公共组件

由于Web框架就是用来【接收用户请求】-> 【处理用户请求】-> 【响应相关内容】，对于具体如何处理用户请求，开发人员根据用户请求来进行处理，而对于接收用户请求和相应相关的内容均交给框架本身来处理，其处理完成之后将产出交给开发人员和用户。

【接收用户请求】

当框架接收到用户请求之后，将请求信息封装在Bottle的request中，以供开发人员使用

【响应相关内容】

当开发人员的代码处理完用户请求之后，会将其执行内容相应给用户，相应的内容会封装在Bottle的response中，然后再由框架将内容返回给用户

所以，公共组件本质其实就是为开发人员提供接口，使其能够获取用户信息并配置响应内容。

1、request

Bottle中的request其实是一个LocalReqeust对象，其中封装了用户请求的相关信息：

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request.headers
    请求头信息
 
request.query
    get请求信息
 
request.forms
    post请求信息
 
request.files
    上传文件信息
 
request.params
    get和post请求信息
 
request.GET
    get请求信息
 
request.POST
    post和上传信息
 
request.cookies
    cookie信息
     
request.environ
    环境相关相关

2、response

Bottle中的request其实是一个LocalResponse对象，其中框架即将返回给用户的相关信息：

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response
    response.status_line
        状态行
 
    response.status_code
        状态码
 
    response.headers
        响应头
 
    response.charset
        编码
 
    response.set_cookie
        在浏览器上设置cookie
         
    response.delete_cookie
        在浏览器上删除cookie

实例：

from bottle import route, request

@route('/login')

def login():

    return '''

        <form action="/login" method="post">

            Username: <input name="username" type="text" />

            Password: <input name="password" type="password" />

            <input value="Login" type="submit" />

        </form>

    '''

@route('/login', method='POST')

def do_login():

    username = request.forms.get('username')

    password = request.forms.get('password')

    if check_login(username, password):

        return "<p>Your login information was correct.</p>"

    else:

        return "<p>Login failed.</p>"

基本Form请求

<form action="/upload" method="post" enctype="multipart/form-data">

  Category:      <input type="text" name="category" />

  Select a file: <input type="file" name="upload" />

  <input type="submit" value="Start upload" />

</form>

@route('/upload', method='POST')

def do_upload():

    category   = request.forms.get('category')

    upload     = request.files.get('upload')

    name, ext = os.path.splitext(upload.filename)

    if ext not in ('.png','.jpg','.jpeg'):

        return 'File extension not allowed.'

    save_path = get_save_path_for_category(category)

    upload.save(save_path) # appends upload.filename automatically

    return 'OK'

上传文件

四、服务

对于Bottle框架其本身未实现类似于Tornado自己基于socket实现Web服务，所以必须依赖WSGI，默认Bottle已经实现并且支持的WSGI有：

server_names = {

    'cgi': CGIServer,

    'flup': FlupFCGIServer,

    'wsgiref': WSGIRefServer,

    'waitress': WaitressServer,

    'cherrypy': CherryPyServer,

    'paste': PasteServer,

    'fapws3': FapwsServer,

    'tornado': TornadoServer,

    'gae': AppEngineServer,

    'twisted': TwistedServer,

    'diesel': DieselServer,

    'meinheld': MeinheldServer,

    'gunicorn': GunicornServer,

    'eventlet': EventletServer,

    'gevent': GeventServer,

    'geventSocketIO':GeventSocketIOServer,

    'rocket': RocketServer,

    'bjoern' : BjoernServer,

    'auto': AutoServer,

}

WSGI

使用时，只需在主app执行run方法时指定参数即可：

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from bottle import Bottle
root = Bottle()
 
@root.route('/hello/')
def index():
    return "Hello World"
# 默认server ＝'wsgiref'
root.run(host='localhost', port=8080, server='wsgiref')

默认server＝"wsgiref"，即：使用Python内置模块wsgiref，如果想要使用其他时，则需要首先安装相关类库，然后才能使用。如：

# 如果使用Tornado的服务，则需要首先安装tornado才能使用

class TornadoServer(ServerAdapter):

    """ The super hyped asynchronous server by facebook. Untested. """

    def run(self, handler): # pragma: no cover

        # 导入Tornado相关模块

        import tornado.wsgi, tornado.httpserver, tornado.ioloop

        container = tornado.wsgi.WSGIContainer(handler)

        server = tornado.httpserver.HTTPServer(container)

        server.listen(port=self.port,address=self.host)

        tornado.ioloop.IOLoop.instance().start()

bottle.py源码

PS：以上WSGI中提供了19种，如果想要使期支持其他服务，则需要扩展Bottle源码来自定义一个ServerAdapter

更多参见：http://www.bottlepy.org/docs/dev/index.html

Flask

Flask是一个基于Python开发并且依赖jinja2模板和Werkzeug WSGI服务的一个微型框架，对于Werkzeug本质是Socket服务端，其用于接收http请求并对请求进行预处理，然后触发Flask框架，开发人员基于Flask框架提供的功能对请求进行相应的处理，并返回给用户，如果要返回给用户复杂的内容时，需要借助jinja2模板来实现对模板的处理，即：将模板和数据进行渲染，将渲染后的字符串返回给用户浏览器。

“微”(micro) 并不表示你需要把整个 Web 应用塞进单个 Python 文件（虽然确实可以 ），也不意味着 Flask 在功能上有所欠缺。微框架中的“微”意味着 Flask 旨在保持核心简单而易于扩展。Flask 不会替你做出太多决策——比如使用何种数据库。而那些 Flask 所选择的——比如使用何种模板引擎——则很容易替换。除此之外的一切都由可由你掌握。如此，Flask 可以与您珠联璧合。

默认情况下，Flask 不包含数据库抽象层、表单验证，或是其它任何已有多种库可以胜任的功能。然而，Flask 支持用扩展来给应用添加这些功能，如同是 Flask 本身实现的一样。众多的扩展提供了数据库集成、表单验证、上传处理、各种各样的开放认证技术等功能。Flask 也许是“微小”的，但它已准备好在需求繁杂的生产环境中投入使用。

安装

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pip install Flask
 
#!/usr/bin/env python

# -*- coding:utf-8 -*-

from werkzeug.wrappers import Request, Response

@Request.application

def hello(request):

    return Response('Hello World!')

if __name__ == '__main__':

    from werkzeug.serving import run_simple

    run_simple('localhost', 4000, hello)

werkzeug

一、第一次

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from flask import Flask
app = Flask(__name__)
 
@app.route("/")
def hello():
    return "Hello World!"
 
if __name__ == "__main__":
    app.run()

二、路由系统

  • @app.route('/user/<username>')
  • @app.route('/post/<int:post_id>')
  • @app.route('/post/<float:post_id>')
  • @app.route('/post/<path:path>')
  • @app.route('/login', methods=['GET', 'POST'])

常用路由系统有以上五种，所有的路由系统都是基于一下对应关系来处理：

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DEFAULT_CONVERTERS = {
    'default':          UnicodeConverter,
    'string':           UnicodeConverter,
    'any':              AnyConverter,
    'path':             PathConverter,
    'int':              IntegerConverter,
    'float':            FloatConverter,
    'uuid':             UUIDConverter,
}

注：对于Flask默认不支持直接写正则表达式的路由，不过可以通过自定义来实现，见：https://segmentfault.com/q/1010000000125259

三、模板

1、模板的使用

Flask使用的是Jinja2模板，所以其语法和Django无差别

2、自定义模板方法

Flask中自定义模板方法的方式和Bottle相似，创建一个函数并通过参数的形式传入render_template，如：

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

</head>

<body>

    <h1>自定义函数</h1>

    {{ww()|safe}}

</body>

</html>

index.html

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask,render_template
app = Flask(__name__)
 
 
def wupeiqi():
    return '<h1>Wupeiqi</h1>'
 
@app.route('/login', methods=['GET', 'POST'])
def login():
    return render_template('login.html', ww=wupeiqi)
 
app.run()

四、公共组件

1、请求

对于Http请求，Flask会讲请求信息封装在request中(werkzeug.wrappers.BaseRequest)，提供的如下常用方法和字段以供使用：

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request.method
request.args
request.form
request.values
request.files
request.cookies
request.headers
request.path
request.full_path
request.script_root
request.url
request.base_url
request.url_root
request.host_url
request.host
 
@app.route('/login', methods=['POST', 'GET'])

def login():

    error = None

    if request.method == 'POST':

        if valid_login(request.form['username'],

                       request.form['password']):

            return log_the_user_in(request.form['username'])

        else:

            error = 'Invalid username/password'

    # the code below is executed if the request method

    # was GET or the credentials were invalid

    return render_template('login.html', error=error)

表单处理Demo

from flask import request

from werkzeug import secure_filename

@app.route('/upload', methods=['GET', 'POST'])

def upload_file():

    if request.method == 'POST':

        f = request.files['the_file']

        f.save('/var/www/uploads/' + secure_filename(f.filename))

    ...

上传文件Demo

from flask import request

@app.route('/setcookie/')

def index():

    username = request.cookies.get('username')

    # use cookies.get(key) instead of cookies[key] to not get a

    # KeyError if the cookie is missing.

from flask import make_response

@app.route('/getcookie')

def index():

    resp = make_response(render_template(...))

    resp.set_cookie('username', 'the username')

    return resp

Cookie操作

2、响应

当用户请求被开发人员的逻辑处理完成之后，会将结果发送给用户浏览器，那么就需要对请求做出相应的响应。

a.字符串

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@app.route('/index/', methods=['GET', 'POST'])
def index():
    return "index"

b.模板引擎

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from flask import Flask,render_template,request
app = Flask(__name__)
 
@app.route('/index/', methods=['GET', 'POST'])
def index():
    return render_template("index.html")
 
app.run()

c.重定向

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
from flask import Flask, redirect, url_for
app = Flask(__name__)
 
@app.route('/index/', methods=['GET', 'POST'])
def index():
    # return redirect('/login/')
    return redirect(url_for('login'))
 
@app.route('/login/', methods=['GET', 'POST'])
def login():
    return "LOGIN"
 
app.run()

d.错误页面

from flask import Flask, abort, render_template

app = Flask(__name__)

@app.route('/e1/', methods=['GET', 'POST'])

def index():

    abort(404, 'Nothing')

app.run()

指定URL，简单错误

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from flask import Flask, abort, render_template
app = Flask(__name__)
 
@app.route('/index/', methods=['GET', 'POST'])
def index():
    return "OK"
 
@app.errorhandler(404)
def page_not_found(error):
    return render_template('page_not_found.html'), 404
 
app.run()

e.设置相应信息

使用make_response可以对相应的内容进行操作

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from flask import Flask, abort, render_template,make_response
app = Flask(__name__)
 
@app.route('/index/', methods=['GET', 'POST'])
def index():
    response = make_response(render_template('index.html'))
    # response是flask.wrappers.Response类型
    # response.delete_cookie
    # response.set_cookie
    # response.headers['X-Something'] = 'A value'
    return response
 
app.run()

3、Session

除请求对象之外，还有一个 session 对象。它允许你在不同请求间存储特定用户的信息。它是在 Cookies 的基础上实现的，并且对 Cookies 进行密钥签名要使用会话，你需要设置一个密钥。

  • 设置：session['username'] ＝ 'xxx'

  • 删除：session.pop('username', None)
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from flask import Flask, session, redirect, url_for, escape, request
 
app = Flask(__name__)
 
@app.route('/')
def index():
    if 'username' in session:
        return 'Logged in as %s' % escape(session['username'])
    return 'You are not logged in'
 
@app.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        session['username'] = request.form['username']
        return redirect(url_for('index'))
    return '''
        <form action="" method="post">
            <p><input type=text name=username>
            <p><input type=submit value=Login>
        </form>
    '''
 
@app.route('/logout')
def logout():
    # remove the username from the session if it's there
    session.pop('username', None)
    return redirect(url_for('index'))
 
# set the secret key.  keep this really secret:
app.secret_key = 'A0Zr98j/3yX R~XHH!jmN]LWX/,?RT'

4.message

message是一个基于Session实现的用于保存数据的集合，其特点是：使用一次就删除

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

</head>

<body>

    {% with messages = get_flashed_messages() %}

        {% if messages %}

        <ul class=flashes>

            {% for message in messages %}

            <li>{{ message }}</li>

            {% endfor %}

        </ul>

        {% endif %}

    {% endwith %}

</body>

</html>

index.html

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from flask import Flask, flash, redirect, render_template, request
 
app = Flask(__name__)
app.secret_key = 'some_secret'
 
@app.route('/')
def index1():
    return render_template('index.html')
 
@app.route('/set')
def index2():
    v = request.args.get('p')
    flash(v)
    return 'ok'
 
if __name__ == "__main__":
    app.run()

5.中间件

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from flask import Flask, flash, redirect, render_template, request
 
app = Flask(__name__)
app.secret_key = 'some_secret'
 
@app.route('/')
def index1():
    return render_template('index.html')
 
@app.route('/set')
def index2():
    v = request.args.get('p')
    flash(v)
    return 'ok'
 
class MiddleWare:
    def __init__(self,wsgi_app):
        self.wsgi_app = wsgi_app
 
    def __call__(self, *args, **kwargs):
 
        return self.wsgi_app(*args, **kwargs)
 
if __name__ == "__main__":
    app.wsgi_app = MiddleWare(app.wsgi_app)
    app.run(port=9999)

Flask还有众多其他功能，更多参见：
    http://docs.jinkan.org/docs/flask/
    http://flask.pocoo.org/

Tornado

Tornado 是 FriendFeed 使用的可扩展的非阻塞式 web 服务器及其相关工具的开源版本。这个 Web 框架看起来有些像web.py 或者 Google 的 webapp，不过为了能有效利用非阻塞式服务器环境，这个 Web 框架还包含了一些相关的有用工具 和优化。

Tornado 和现在的主流 Web 服务器框架（包括大多数 Python 的框架）有着明显的区别：它是非阻塞式服务器，而且速度相当快。得利于其 非阻塞的方式和对 epoll 的运用，Tornado 每秒可以处理数以千计的连接，这意味着对于实时 Web 服务来说，Tornado 是一个理想的 Web 框架。我们开发这个 Web 服务器的主要目的就是为了处理 FriendFeed 的实时功能 ——在 FriendFeed 的应用里每一个活动用户都会保持着一个服务器连接。（关于如何扩容 服务器，以处理数以千计的客户端的连接的问题，请参阅 C10K problem。）

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pip install tornado
源码安装
    https://pypi.python.org/packages/source/t/tornado/tornado-4.3.tar.gz

一、快速上手

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
import tornado.ioloop
import tornado.web
  
  
class MainHandler(tornado.web.RequestHandler):
    def get(self):
        self.write("Hello, world")
  
application = tornado.web.Application([
    (r"/index", MainHandler),
])
  
  
if __name__ == "__main__":
    application.listen(8888)
    tornado.ioloop.IOLoop.instance().start()

第一步：执行脚本，监听 8888 端口

第二步：浏览器客户端访问 /index  -->  http://127.0.0.1:8888/index

第三步：服务器接受请求，并交由对应的类处理该请求

第四步：类接受到请求之后，根据请求方式（post / get / delete ...）的不同调用并执行相应的方法

第五步：方法返回值的字符串内容发送浏览器

#!/usr/bin/env python

# -*- coding:utf-8 -*-

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

from tornado import httpclient

from tornado.web import asynchronous

from tornado import gen

import uimodules as md

import uimethods as mt

class MainHandler(tornado.web.RequestHandler):

        @asynchronous

        @gen.coroutine

        def get(self):

            print 'start get '

            http = httpclient.AsyncHTTPClient()

            http.fetch("http://127.0.0.1:8008/post/", self.callback)

            self.write('end')

        def callback(self, response):

            print response.body

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

    'ui_methods': mt,

    'ui_modules': md,

}

application = tornado.web.Application([

    (r"/index", MainHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8009)

    tornado.ioloop.IOLoop.instance().start()

异步非阻塞实例

二、路由系统

路由系统其实就是 url 和 类 的对应关系，这里不同于其他框架，其他很多框架均是 url 对应 函数，Tornado中每个url对应的是一个类。

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
import tornado.ioloop
import tornado.web
  
  
class MainHandler(tornado.web.RequestHandler):
    def get(self):
        self.write("Hello, world")
  
class StoryHandler(tornado.web.RequestHandler):
    def get(self, story_id):
        self.write("You requested the story " + story_id)
  
class BuyHandler(tornado.web.RequestHandler):
    def get(self):
        self.write("buy.wupeiqi.com/index")
  
application = tornado.web.Application([
    (r"/index", MainHandler),
    (r"/story/([0-9]+)", StoryHandler),
])
  
application.add_handlers('buy.wupeiqi.com$', [
    (r'/index',BuyHandler),
])
  
if __name__ == "__main__":
    application.listen(80)
    tornado.ioloop.IOLoop.instance().start()

三、模板

Tornao中的模板语言和django中类似，模板引擎将模板文件载入内存，然后将数据嵌入其中，最终获取到一个完整的字符串，再将字符串返回给请求者。

Tornado 的模板支持“控制语句”和“表达语句”，控制语句是使用 {% 和 %} 包起来的 例如 {% if len(items) > 2 %}。表达语句是使用 {{ 和 }} 包起来的，例如 {{ items[0] }}。

控制语句和对应的 Python 语句的格式基本完全相同。我们支持 if、for、while 和 try，这些语句逻辑结束的位置需要用 {% end %} 做标记。还通过 extends 和 block 语句实现了模板继承。这些在 template 模块 的代码文档中有着详细的描述。

<!DOCTYPE html>

<html>

<head>

    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>

    <title>老男孩</title>

    <link href="{{static_url("css/common.css")}}" rel="stylesheet" />

    {% block CSS %}{% end %}

</head>

<body>

    <div class="pg-header">

    </div>

    {% block RenderBody %}{% end %}

    <script src="{{static_url("js/jquery-1.8.2.min.js")}}"></script>

    {% block JavaScript %}{% end %}

</body>

</html>

layout.html

{% extends 'layout.html'%}

{% block CSS %}

    <link href="{{static_url("css/index.css")}}" rel="stylesheet" />

{% end %}

{% block RenderBody %}

    <h1>Index</h1>

    <ul>

    {%  for item in li %}

        <li>{{item}}</li>

    {% end %}

    </ul>

{% end %}

{% block JavaScript %}

{% end %}

index.html

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
import tornado.ioloop
import tornado.web
  
  
class MainHandler(tornado.web.RequestHandler):
    def get(self):
        self.render('home/index.html')
  
settings = {
    'template_path': 'template',
}
  
application = tornado.web.Application([
    (r"/index", MainHandler),
], **settings)
  
  
if __name__ == "__main__":
    application.listen(80)
    tornado.ioloop.IOLoop.instance().start()

在模板中默认提供了一些函数、字段、类以供模板使用：

  • escape: tornado.escape.xhtml_escape 的別名
  • xhtml_escape: tornado.escape.xhtml_escape 的別名
  • url_escape: tornado.escape.url_escape 的別名
  • json_encode: tornado.escape.json_encode 的別名
  • squeeze: tornado.escape.squeeze 的別名
  • linkify: tornado.escape.linkify 的別名
  • datetime: Python 的 datetime 模组
  • handler: 当前的 RequestHandler 对象
  • request: handler.request 的別名
  • current_user: handler.current_user 的別名
  • locale: handler.locale 的別名
  • _: handler.locale.translate 的別名
  • static_url: for handler.static_url 的別名
  • xsrf_form_html: handler.xsrf_form_html 的別名

Tornado默认提供的这些功能其实本质上就是 UIMethod 和 UIModule，我们也可以自定义从而实现类似于Django的simple_tag的功能：
1、定义

# uimethods.py

def tab(self):

    return 'UIMethod'

uimethods.py

#!/usr/bin/env python

# -*- coding:utf-8 -*-

from tornado.web import UIModule

from tornado import escape

class custom(UIModule):

    def render(self, *args, **kwargs):

        return escape.xhtml_escape('<h1>wupeiqi</h1>')

        #return escape.xhtml_escape('<h1>wupeiqi</h1>')

uimodules.py

2、注册

#!/usr/bin/env python

# -*- coding:utf-8 -*-

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

from tornado.escape import linkify

import uimodules as md

import uimethods as mt

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        self.render('index.html')

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

    'ui_methods': mt,

    'ui_modules': md,

}

application = tornado.web.Application([

    (r"/index", MainHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8009)

    tornado.ioloop.IOLoop.instance().start()

main.py

3、使用

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

    <link href="{{static_url("commons.css")}}" rel="stylesheet" />

</head>

<body>

    <h1>hello</h1>

    {% module custom(123) %}

    {{ tab() }}

</body>

index.html

四、实用功能

1、静态文件

对于静态文件，可以配置静态文件的目录和前段使用时的前缀，并且Tornaodo还支持静态文件缓存。

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        self.render('home/index.html')

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

}

application = tornado.web.Application([

    (r"/index", MainHandler),

], **settings)

if __name__ == "__main__":

    application.listen(80)

    tornado.ioloop.IOLoop.instance().start()

main.py

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

    <link href="{{static_url("commons.css")}}" rel="stylesheet" />

</head>

<body>

    <h1>hello</h1>

</body>

</html>

index.html

备注：静态文件缓存的实现

    def get_content_version(cls, abspath):

        """Returns a version string for the resource at the given path.

        This class method may be overridden by subclasses.  The

        default implementation is a hash of the file's contents.

        .. versionadded:: 3.1

        """

        data = cls.get_content(abspath)

        hasher = hashlib.md5()

        if isinstance(data, bytes):

            hasher.update(data)

        else:

            for chunk in data:

                hasher.update(chunk)

        return hasher.hexdigest()

静态文件缓存源码

2、csrf

Tornado中的夸张请求伪造和Django中的相似，跨站伪造请求(Cross-site request forgery)

settings = {

    "xsrf_cookies": True,

}

application = tornado.web.Application([

    (r"/", MainHandler),

    (r"/login", LoginHandler),

], **settings)

配置

<form action="/new_message" method="post">

  {{ xsrf_form_html() }}

  <input type="text" name="message"/>

  <input type="submit" value="Post"/>

</form>

普通表单使用

function getCookie(name) {

    var r = document.cookie.match("\\b" + name + "=([^;]*)\\b");

    return r ? r[1] : undefined;

}

jQuery.postJSON = function(url, args, callback) {

    args._xsrf = getCookie("_xsrf");

    $.ajax({url: url, data: $.param(args), dataType: "text", type: "POST",

        success: function(response) {

        callback(eval("(" + response + ")"));

    }});

};

Ajax使用

注：Ajax使用时，本质上就是去获取本地的cookie，携带cookie再来发送请求

3、cookie

Tornado中可以对cookie进行操作，并且还可以对cookie进行签名以放置伪造。

a、基本操作

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        if not self.get_cookie("mycookie"):

            self.set_cookie("mycookie", "myvalue")

            self.write("Your cookie was not set yet!")

        else:

            self.write("Your cookie was set!")

Code

b、签名

Cookie 很容易被恶意的客户端伪造。加入你想在 cookie 中保存当前登陆用户的 id 之类的信息，你需要对 cookie 作签名以防止伪造。Tornado 通过 set_secure_cookie 和 get_secure_cookie 方法直接支持了这种功能。 要使用这些方法，你需要在创建应用时提供一个密钥，名字为 cookie_secret。 你可以把它作为一个关键词参数传入应用的设置中：

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        if not self.get_secure_cookie("mycookie"):

            self.set_secure_cookie("mycookie", "myvalue")

            self.write("Your cookie was not set yet!")

        else:

            self.write("Your cookie was set!")

application = tornado.web.Application([

    (r"/", MainHandler),

], cookie_secret="61oETzKXQAGaYdkL5gEmGeJJFuYh7EQnp2XdTP1o/Vo=")

Code

def _create_signature_v1(secret, *parts):

    hash = hmac.new(utf8(secret), digestmod=hashlib.sha1)

    for part in parts:

        hash.update(utf8(part))

    return utf8(hash.hexdigest())

def _create_signature_v2(secret, s):

    hash = hmac.new(utf8(secret), digestmod=hashlib.sha256)

    hash.update(utf8(s))

    return utf8(hash.hexdigest())

内部算法

def create_signed_value(secret, name, value, version=None, clock=None,

                        key_version=None):

    if version is None:

        version = DEFAULT_SIGNED_VALUE_VERSION

    if clock is None:

        clock = time.time

    timestamp = utf8(str(int(clock())))

    value = base64.b64encode(utf8(value))

    if version == 1:

        signature = _create_signature_v1(secret, name, value, timestamp)

        value = b"|".join([value, timestamp, signature])

        return value

    elif version == 2:

        # The v2 format consists of a version number and a series of

        # length-prefixed fields "%d:%s", the last of which is a

        # signature, all separated by pipes.  All numbers are in

        # decimal format with no leading zeros.  The signature is an

        # HMAC-SHA256 of the whole string up to that point, including

        # the final pipe.

        #

        # The fields are:

        # - format version (i.e. 2; no length prefix)

        # - key version (integer, default is 0)

        # - timestamp (integer seconds since epoch)

        # - name (not encoded; assumed to be ~alphanumeric)

        # - value (base64-encoded)

        # - signature (hex-encoded; no length prefix)

        def format_field(s):

            return utf8("%d:" % len(s)) + utf8(s)

        to_sign = b"|".join([

            b"",

            format_field(str(key_version or 0)),

            format_field(timestamp),

            format_field(name),

            format_field(value),

            b''])

        if isinstance(secret, dict):

            assert key_version is not None, 'Key version must be set when sign key dict is used'

            assert version >= 2, 'Version must be at least 2 for key version support'

            secret = secret[key_version]

        signature = _create_signature_v2(secret, to_sign)

        return to_sign + signature

    else:

        raise ValueError("Unsupported version %d" % version)

内部算法-加密

def _decode_signed_value_v1(secret, name, value, max_age_days, clock):

    parts = utf8(value).split(b"|")

    if len(parts) != 3:

        return None

    signature = _create_signature_v1(secret, name, parts[0], parts[1])

    if not _time_independent_equals(parts[2], signature):

        gen_log.warning("Invalid cookie signature %r", value)

        return None

    timestamp = int(parts[1])

    if timestamp < clock() - max_age_days * 86400:

        gen_log.warning("Expired cookie %r", value)

        return None

    if timestamp > clock() + 31 * 86400:

        # _cookie_signature does not hash a delimiter between the

        # parts of the cookie, so an attacker could transfer trailing

        # digits from the payload to the timestamp without altering the

        # signature.  For backwards compatibility, sanity-check timestamp

        # here instead of modifying _cookie_signature.

        gen_log.warning("Cookie timestamp in future; possible tampering %r",

                        value)

        return None

    if parts[1].startswith(b""):

        gen_log.warning("Tampered cookie %r", value)

        return None

    try:

        return base64.b64decode(parts[0])

    except Exception:

        return None

def _decode_fields_v2(value):

    def _consume_field(s):

        length, _, rest = s.partition(b':')

        n = int(length)

        field_value = rest[:n]

        # In python 3, indexing bytes returns small integers; we must

        # use a slice to get a byte string as in python 2.

        if rest[n:n + 1] != b'|':

            raise ValueError("malformed v2 signed value field")

        rest = rest[n + 1:]

        return field_value, rest

    rest = value[2:]  # remove version number

    key_version, rest = _consume_field(rest)

    timestamp, rest = _consume_field(rest)

    name_field, rest = _consume_field(rest)

    value_field, passed_sig = _consume_field(rest)

    return int(key_version), timestamp, name_field, value_field, passed_sig

def _decode_signed_value_v2(secret, name, value, max_age_days, clock):

    try:

        key_version, timestamp, name_field, value_field, passed_sig = _decode_fields_v2(value)

    except ValueError:

        return None

    signed_string = value[:-len(passed_sig)]

    if isinstance(secret, dict):

        try:

            secret = secret[key_version]

        except KeyError:

            return None

    expected_sig = _create_signature_v2(secret, signed_string)

    if not _time_independent_equals(passed_sig, expected_sig):

        return None

    if name_field != utf8(name):

        return None

    timestamp = int(timestamp)

    if timestamp < clock() - max_age_days * 86400:

        # The signature has expired.

        return None

    try:

        return base64.b64decode(value_field)

    except Exception:

        return None

def get_signature_key_version(value):

    value = utf8(value)

    version = _get_version(value)

    if version < 2:

        return None

    try:

        key_version, _, _, _, _ = _decode_fields_v2(value)

    except ValueError:

        return None

    return key_version

内部算法-解密

签名Cookie的本质是：

写cookie过程：

  • 将值进行base64加密
  • 对除值以外的内容进行签名，哈希算法（无法逆向解析）
  • 拼接 签名 + 加密值

读cookie过程：

  • 读取 签名 + 加密值
  • 对签名进行验证
  • base64解密，获取值内容

注：许多API验证机制和安全cookie的实现机制相同。

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        login_user = self.get_secure_cookie("login_user", None)

        if login_user:

            self.write(login_user)

        else:

            self.redirect('/login')

class LoginHandler(tornado.web.RequestHandler):

    def get(self):

        self.current_user()

        self.render('login.html', **{'status': ''})

    def post(self, *args, **kwargs):

        username = self.get_argument('name')

        password = self.get_argument('pwd')

        if username == 'wupeiqi' and password == '':

            self.set_secure_cookie('login_user', '武沛齐')

            self.redirect('/')

        else:

            self.render('login.html', **{'status': '用户名或密码错误'})

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

    'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh'

}

application = tornado.web.Application([

    (r"/index", MainHandler),

    (r"/login", LoginHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8888)

    tornado.ioloop.IOLoop.instance().start()

Demo-基于cookie进行用户验证

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

class BaseHandler(tornado.web.RequestHandler):

    def get_current_user(self):

        return self.get_secure_cookie("login_user")

class MainHandler(BaseHandler):

    @tornado.web.authenticated

    def get(self):

        login_user = self.current_user

        self.write(login_user)

class LoginHandler(tornado.web.RequestHandler):

    def get(self):

        self.current_user()

        self.render('login.html', **{'status': ''})

    def post(self, *args, **kwargs):

        username = self.get_argument('name')

        password = self.get_argument('pwd')

        if username == 'wupeiqi' and password == '':

            self.set_secure_cookie('login_user', '武沛齐')

            self.redirect('/')

        else:

            self.render('login.html', **{'status': '用户名或密码错误'})

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

    'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh',

    'login_url': '/login'

}

application = tornado.web.Application([

    (r"/index", MainHandler),

    (r"/login", LoginHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8888)

    tornado.ioloop.IOLoop.instance().start()

Demo-Toando内部提供基于cookie进行用户验证

4、Ajax上传文件

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

</head>

<body>

    <input type="file" id="img" />

    <input type="button" onclick="UploadFile();" />

    <script>

        function UploadFile(){

            var fileObj = document.getElementById("img").files[0];

            var form = new FormData();

            form.append("k1", "v1");

            form.append("fff", fileObj);

            var xhr = new XMLHttpRequest();

            xhr.open("post", '/index', true);

            xhr.send(form);

        }

    </script>

</body>

</html>

Html

#!/usr/bin/env python

# -*- coding:utf-8 -*-

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        self.render('index.html')

    def post(self, *args, **kwargs):

        file_metas = self.request.files["fff"]

        # print(file_metas)

        for meta in file_metas:

            file_name = meta['filename']

            with open(file_name,'wb') as up:

                up.write(meta['body'])

settings = {

    'template_path': 'template',

}

application = tornado.web.Application([

    (r"/index", MainHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8000)

    tornado.ioloop.IOLoop.instance().start()

Python

var fileObj = $("#img")[0].files[0];

var form = new FormData();

form.append("k1", "v1");

form.append("fff", fileObj);

$.ajax({

    type:'POST',

    url: '/index',

    data: form,

    processData: false,  // tell jQuery not to process the data

    contentType: false,  // tell jQuery not to set contentType

    success: function(arg){

        console.log(arg);

    }

})

jQuery Ajax Upload

五、扩展功能

1、自定义Session

a.知识储备

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
class Foo(object):
  
    def __getitem__(self, key):
        print  '__getitem__',key
  
    def __setitem__(self, key, value):
        print '__setitem__',key,value
  
    def __delitem__(self, key):
        print '__delitem__',key
  
  
  
obj = Foo()
result = obj['k1']
#obj['k2'] = 'wupeiqi'
#del obj['k1']

b.session实现机制

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
import tornado.ioloop
import tornado.web
from hashlib import sha1
import os, time
  
session_container = {}
  
create_session_id = lambda: sha1('%s%s' % (os.urandom(16), time.time())).hexdigest()
  
  
class Session(object):
  
    session_id = "__sessionId__"
  
    def __init__(self, request):
        session_value = request.get_cookie(Session.session_id)
        if not session_value:
            self._id = create_session_id()
        else:
            self._id = session_value
        request.set_cookie(Session.session_id, self._id)
  
    def __getitem__(self, key):
        return session_container[self._id][key]
  
    def __setitem__(self, key, value):
        if session_container.has_key(self._id):
            session_container[self._id][key] = value
        else:
            session_container[self._id] = {key: value}
  
    def __delitem__(self, key):
        del session_container[self._id][key]
  
  
class BaseHandler(tornado.web.RequestHandler):
  
    def initialize(self):
        # my_session['k1']访问 __getitem__ 方法
        self.my_session = Session(self)
  
  
class MainHandler(BaseHandler):
  
    def get(self):
        print self.my_session['c_user']
        print self.my_session['c_card']
        self.write('index')
  
class LoginHandler(BaseHandler):
  
    def get(self):
        self.render('login.html', **{'status': ''})
  
    def post(self, *args, **kwargs):
  
        username = self.get_argument('name')
        password = self.get_argument('pwd')
        if username == 'wupeiqi' and password == '123':
  
            self.my_session['c_user'] = 'wupeiqi'
            self.my_session['c_card'] = '12312312309823012'
  
            self.redirect('/index')
        else:
            self.render('login.html', **{'status': '用户名或密码错误'})
  
settings = {
    'template_path': 'template',
    'static_path': 'static',
    'static_url_prefix': '/static/',
    'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh',
    'login_url': '/login'
}
  
application = tornado.web.Application([
    (r"/index", MainHandler),
    (r"/login", LoginHandler),
], **settings)
  
  
if __name__ == "__main__":
    application.listen(8888)
    tornado.ioloop.IOLoop.instance().start()

c. Session框架

#!/usr/bin/env python

#coding:utf-8

import sys

import math

from bisect import bisect

if sys.version_info >= (2, 5):

    import hashlib

    md5_constructor = hashlib.md5

else:

    import md5

    md5_constructor = md5.new

class HashRing(object):

    """一致性哈希"""

    def __init__(self,nodes):

        '''初始化

        nodes : 初始化的节点，其中包含节点已经节点对应的权重

                默认每一个节点有32个虚拟节点

                对于权重，通过多创建虚拟节点来实现

                如：nodes = [

                        {'host':'127.0.0.1:8000','weight':1},

                        {'host':'127.0.0.1:8001','weight':2},

                        {'host':'127.0.0.1:8002','weight':1},

                    ]

        '''

        self.ring = dict()

        self._sorted_keys = []

        self.total_weight = 0

        self.__generate_circle(nodes)

    def __generate_circle(self,nodes):

        for node_info in nodes:

            self.total_weight += node_info.get('weight',1)

        for node_info in nodes:

            weight = node_info.get('weight',1)

            node = node_info.get('host',None)

            virtual_node_count = math.floor((32*len(nodes)*weight) / self.total_weight)

            for i in xrange(0,int(virtual_node_count)):

                key = self.gen_key_thirty_two( '%s-%s' % (node, i) )

                if self._sorted_keys.__contains__(key):

                    raise Exception('该节点已经存在.')

                self.ring[key] = node

                self._sorted_keys.append(key)

    def add_node(self,node):

        ''' 新建节点

        node : 要添加的节点，格式为：{'host':'127.0.0.1:8002','weight':1}，其中第一个元素表示节点，第二个元素表示该节点的权重。

        '''

        node = node.get('host',None)

        if not node:

                raise Exception('节点的地址不能为空.')

        weight = node.get('weight',1)

        self.total_weight += weight

        nodes_count = len(self._sorted_keys) + 1

        virtual_node_count = math.floor((32 * nodes_count * weight) / self.total_weight)

        for i in xrange(0,int(virtual_node_count)):

            key = self.gen_key_thirty_two( '%s-%s' % (node, i) )

            if self._sorted_keys.__contains__(key):

                raise Exception('该节点已经存在.')

            self.ring[key] = node

            self._sorted_keys.append(key)

    def remove_node(self,node):

        ''' 移除节点

        node : 要移除的节点 '127.0.0.1:8000'

        '''

        for key,value in self.ring.items():

            if value == node:

                del self.ring[key]

                self._sorted_keys.remove(key)

    def get_node(self,string_key):

        '''获取 string_key 所在的节点'''

        pos = self.get_node_pos(string_key)

        if pos is None:

            return None

        return self.ring[ self._sorted_keys[pos]].split(':')

    def get_node_pos(self,string_key):

        '''获取 string_key 所在的节点的索引'''

        if not self.ring:

            return None

        key = self.gen_key_thirty_two(string_key)

        nodes = self._sorted_keys

        pos = bisect(nodes, key)

        return pos

    def gen_key_thirty_two(self, key):

        m = md5_constructor()

        m.update(key)

        return long(m.hexdigest(), 16)

    def gen_key_sixteen(self,key):

        b_key = self.__hash_digest(key)

        return self.__hash_val(b_key, lambda x: x)

    def __hash_val(self, b_key, entry_fn):

        return (( b_key[entry_fn(3)] << 24)|(b_key[entry_fn(2)] << 16)|(b_key[entry_fn(1)] << 8)| b_key[entry_fn(0)] )

    def __hash_digest(self, key):

        m = md5_constructor()

        m.update(key)

        return map(ord, m.digest())

"""

nodes = [

    {'host':'127.0.0.1:8000','weight':1},

    {'host':'127.0.0.1:8001','weight':2},

    {'host':'127.0.0.1:8002','weight':1},

]

ring = HashRing(nodes)

result = ring.get_node('98708798709870987098709879087')

print result

"""

一致性哈希

from hashlib import sha1

import os, time

create_session_id = lambda: sha1('%s%s' % (os.urandom(16), time.time())).hexdigest()

class Session(object):

    session_id = "__sessionId__"

    def __init__(self, request):

        session_value = request.get_cookie(Session.session_id)

        if not session_value:

            self._id = create_session_id()

        else:

            self._id = session_value

        request.set_cookie(Session.session_id, self._id)

    def __getitem__(self, key):

        # 根据 self._id ，在一致性哈西中找到其对应的服务器IP

        # 找到相对应的redis服务器，如： r = redis.StrictRedis(host='localhost', port=6379, db=0)

        # 使用python redis api 链接

        # 获取数据，即：

        # return self._redis.hget(self._id, name)

    def __setitem__(self, key, value):

        # 根据 self._id ，在一致性哈西中找到其对应的服务器IP

        # 使用python redis api 链接

        # 设置session

        # self._redis.hset(self._id, name, value)

    def __delitem__(self, key):

        # 根据 self._id 找到相对应的redis服务器

        # 使用python redis api 链接

        # 删除，即：

        return self._redis.hdel(self._id, name)

Session

2、自定义模型版定

模型绑定有两个主要功能：

  • 自动生成html表单
  • 用户输入验证

在之前学习的Django中为程序员提供了非常便捷的模型绑定功能，但是在Tornado中，一切需要自己动手！！！

<!DOCTYPE html>

<html>

<head lang="en">

    <meta charset="UTF-8">

    <title></title>

    <link href="{{static_url("commons.css")}}" rel="stylesheet" />

</head>

<body>

    <h1>hello</h1>

    <form action="/index" method="post">

        <p>hostname: <input type="text" name="host" /> </p>

        <p>ip: <input type="text" name="ip" /> </p>

        <p>port: <input type="text" name="port" /> </p>

        <p>phone: <input type="text" name="phone" /> </p>

        <input type="submit" />

    </form>

</body>

</html>

html

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#!/usr/bin/env python
# -*- coding:utf-8 -*-
  
import tornado.ioloop
import tornado.web
from hashlib import sha1
import os, time
import re
  
  
class MainForm(object):
    def __init__(self):
        self.host = "(.*)"
        self.ip = "^(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}$"
        self.port = '(\d+)'
        self.phone = '^1[3|4|5|8][0-9]\d{8}$'
  
    def check_valid(self, request):
        form_dict = self.__dict__
        for key, regular in form_dict.items():
            post_value = request.get_argument(key)
            # 让提交的数据 和 定义的正则表达式进行匹配
            ret = re.match(regular, post_value)
            print key,ret,post_value
  
  
class MainHandler(tornado.web.RequestHandler):
    def get(self):
        self.render('index.html')
    def post(self, *args, **kwargs):
        obj = MainForm()
        result = obj.check_valid(self)
        self.write('ok')
  
  
  
settings = {
    'template_path': 'template',
    'static_path': 'static',
    'static_url_prefix': '/static/',
    'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh',
    'login_url': '/login'
}
  
application = tornado.web.Application([
    (r"/index", MainHandler),
], **settings)
  
  
if __name__ == "__main__":
    application.listen(8888)
    tornado.ioloop.IOLoop.instance().start()

由于请求的验证时，需要考虑是否可以为空以及正则表达式的复用，所以：

#!/usr/bin/env python

# -*- coding:utf-8 -*-

import tornado.ioloop

import tornado.web

import re

class Field(object):

    def __init__(self, error_msg_dict, required):

        self.id_valid = False

        self.value = None

        self.error = None

        self.name = None

        self.error_msg = error_msg_dict

        self.required = required

    def match(self, name, value):

        self.name = name

        if not self.required:

            self.id_valid = True

            self.value = value

        else:

            if not value:

                if self.error_msg.get('required', None):

                    self.error = self.error_msg['required']

                else:

                    self.error = "%s is required" % name

            else:

                ret = re.match(self.REGULAR, value)

                if ret:

                    self.id_valid = True

                    self.value = ret.group()

                else:

                    if self.error_msg.get('valid', None):

                        self.error = self.error_msg['valid']

                    else:

                        self.error = "%s is invalid" % name

class IPField(Field):

    REGULAR = "^(25[0-5]|2[0-4]\d|[0-1]?\d?\d)(\.(25[0-5]|2[0-4]\d|[0-1]?\d?\d)){3}$"

    def __init__(self, error_msg_dict=None, required=True):

        error_msg = {}  # {'required': 'IP不能为空', 'valid': 'IP格式错误'}

        if error_msg_dict:

            error_msg.update(error_msg_dict)

        super(IPField, self).__init__(error_msg_dict=error_msg, required=required)

class IntegerField(Field):

    REGULAR = "^\d+$"

    def __init__(self, error_msg_dict=None, required=True):

        error_msg = {'required': '数字不能为空', 'valid': '数字格式错误'}

        if error_msg_dict:

            error_msg.update(error_msg_dict)

        super(IntegerField, self).__init__(error_msg_dict=error_msg, required=required)

class CheckBoxField(Field):

    def __init__(self, error_msg_dict=None, required=True):

        error_msg = {}  # {'required': 'IP不能为空', 'valid': 'IP格式错误'}

        if error_msg_dict:

            error_msg.update(error_msg_dict)

        super(CheckBoxField, self).__init__(error_msg_dict=error_msg, required=required)

    def match(self, name, value):

        self.name = name

        if not self.required:

            self.id_valid = True

            self.value = value

        else:

            if not value:

                if self.error_msg.get('required', None):

                    self.error = self.error_msg['required']

                else:

                    self.error = "%s is required" % name

            else:

                if isinstance(name, list):

                    self.id_valid = True

                    self.value = value

                else:

                    if self.error_msg.get('valid', None):

                        self.error = self.error_msg['valid']

                    else:

                        self.error = "%s is invalid" % name

class FileField(Field):

    REGULAR = "^(\w+\.pdf)|(\w+\.mp3)|(\w+\.py)$"

    def __init__(self, error_msg_dict=None, required=True):

        error_msg = {}  # {'required': '数字不能为空', 'valid': '数字格式错误'}

        if error_msg_dict:

            error_msg.update(error_msg_dict)

        super(FileField, self).__init__(error_msg_dict=error_msg, required=required)

    def match(self, name, value):

        self.name = name

        self.value = []

        if not self.required:

            self.id_valid = True

            self.value = value

        else:

            if not value:

                if self.error_msg.get('required', None):

                    self.error = self.error_msg['required']

                else:

                    self.error = "%s is required" % name

            else:

                m = re.compile(self.REGULAR)

                if isinstance(value, list):

                    for file_name in value:

                        r = m.match(file_name)

                        if r:

                            self.value.append(r.group())

                            self.id_valid = True

                        else:

                            self.id_valid = False

                            if self.error_msg.get('valid', None):

                                self.error = self.error_msg['valid']

                            else:

                                self.error = "%s is invalid" % name

                            break

                else:

                    if self.error_msg.get('valid', None):

                        self.error = self.error_msg['valid']

                    else:

                        self.error = "%s is invalid" % name

    def save(self, request, upload_path=""):

        file_metas = request.files[self.name]

        for meta in file_metas:

            file_name = meta['filename']

            with open(file_name,'wb') as up:

                up.write(meta['body'])

class Form(object):

    def __init__(self):

        self.value_dict = {}

        self.error_dict = {}

        self.valid_status = True

    def validate(self, request, depth=10, pre_key=""):

        self.initialize()

        self.__valid(self, request, depth, pre_key)

    def initialize(self):

        pass

    def __valid(self, form_obj, request, depth, pre_key):

        """

        验证用户表单请求的数据

        :param form_obj: Form对象（Form派生类的对象）

        :param request: Http请求上下文（用于从请求中获取用户提交的值）

        :param depth: 对Form内容的深度的支持

        :param pre_key: Html中name属性值的前缀（多层Form时，内部递归时设置，无需理会）

        :return: 是否验证通过，True：验证成功；False：验证失败

        """

        depth -= 1

        if depth < 0:

            return None

        form_field_dict = form_obj.__dict__

        for key, field_obj in form_field_dict.items():

            print key,field_obj

            if isinstance(field_obj, Form) or isinstance(field_obj, Field):

                if isinstance(field_obj, Form):

                    # 获取以key开头的所有的值，以参数的形式传至

                    self.__valid(field_obj, request, depth, key)

                    continue

                if pre_key:

                    key = "%s.%s" % (pre_key, key)

                if isinstance(field_obj, CheckBoxField):

                    post_value = request.get_arguments(key, None)

                elif isinstance(field_obj, FileField):

                    post_value = []

                    file_list = request.request.files.get(key, None)

                    for file_item in file_list:

                        post_value.append(file_item['filename'])

                else:

                    post_value = request.get_argument(key, None)

                print post_value

                # 让提交的数据 和 定义的正则表达式进行匹配

                field_obj.match(key, post_value)

                if field_obj.id_valid:

                    self.value_dict[key] = field_obj.value

                else:

                    self.error_dict[key] = field_obj.error

                    self.valid_status = False

class ListForm(object):

    def __init__(self, form_type):

        self.form_type = form_type

        self.valid_status = True

        self.value_dict = {}

        self.error_dict = {}

    def validate(self, request):

        name_list = request.request.arguments.keys() + request.request.files.keys()

        index = 0

        flag = False

        while True:

            pre_key = "[%d]" % index

            for name in name_list:

                if name.startswith(pre_key):

                    flag = True

                    break

            if flag:

                form_obj = self.form_type()

                form_obj.validate(request, depth=10, pre_key="[%d]" % index)

                if form_obj.valid_status:

                    self.value_dict[index] = form_obj.value_dict

                else:

                    self.error_dict[index] = form_obj.error_dict

                    self.valid_status = False

            else:

                break

            index += 1

            flag = False

class MainForm(Form):

    def __init__(self):

        # self.ip = IPField(required=True)

        # self.port = IntegerField(required=True)

        # self.new_ip = IPField(required=True)

        # self.second = SecondForm()

        self.fff = FileField(required=True)

        super(MainForm, self).__init__()

#

# class SecondForm(Form):

#

#     def __init__(self):

#         self.ip = IPField(required=True)

#         self.new_ip = IPField(required=True)

#

#         super(SecondForm, self).__init__()

class MainHandler(tornado.web.RequestHandler):

    def get(self):

        self.render('index.html')

    def post(self, *args, **kwargs):

        # for i in  dir(self.request):

        #     print i

        # print self.request.arguments

        # print self.request.files

        # print self.request.query

        # name_list = self.request.arguments.keys() + self.request.files.keys()

        # print name_list

        # list_form = ListForm(MainForm)

        # list_form.validate(self)

        #

        # print list_form.valid_status

        # print list_form.value_dict

        # print list_form.error_dict

        # obj = MainForm()

        # obj.validate(self)

        #

        # print "验证结果：", obj.valid_status

        # print "符合验证结果：", obj.value_dict

        # print "错误信息:"

        # for key, item in obj.error_dict.items():

        #     print key,item

        # print self.get_arguments('favor'),type(self.get_arguments('favor'))

        # print self.get_argument('favor'),type(self.get_argument('favor'))

        # print type(self.get_argument('fff')),self.get_argument('fff')

        # print self.request.files

        # obj = MainForm()

        # obj.validate(self)

        # print obj.valid_status

        # print obj.value_dict

        # print obj.error_dict

        # print self.request,type(self.request)

        # obj.fff.save(self.request)

        # from tornado.httputil import HTTPServerRequest

        # name_list = self.request.arguments.keys() + self.request.files.keys()

        # print name_list

        # print self.request.files,type(self.request.files)

        # print len(self.request.files.get('fff'))

        # obj = MainForm()

        # obj.validate(self)

        # print obj.valid_status

        # print obj.value_dict

        # print obj.error_dict

        # obj.fff.save(self.request)

        self.write('ok')

settings = {

    'template_path': 'template',

    'static_path': 'static',

    'static_url_prefix': '/static/',

    'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh',

    'login_url': '/login'

}

application = tornado.web.Application([

    (r"/index", MainHandler),

], **settings)

if __name__ == "__main__":

    application.listen(8888)

    tornado.ioloop.IOLoop.instance().start()

Form验证框架

转自：http://www.cnblogs.com/wupeiqi/p/5341480.html

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