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。)

 

 

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  

第一步:执行脚本,监听xxxx端口

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

 

1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 7 8 class MainHandler(tornado.web.RequestHandler): 9 def get(self): 10 self.write("Hello, world") 11 12 application = tornado.web.Application([ 13 ("/index", MainHandler), 14 ]) 15 16 17 if __name__ == "__main__": 18 application.listen(xxxx端口号) 19 tornado.ioloop.IOLoop.instance().start() View Code 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 from tornado import httpclient 7 from tornado.web import asynchronous 8 from tornado import gen 9 10 import uimodules as md 11 import uimethods as mt 12 13 class MainHandler(tornado.web.RequestHandler): 14 @asynchronous 15 @gen.coroutine 16 def get(self): 17 print 'start get ' 18 http = httpclient.AsyncHTTPClient() 19 http.fetch("http://127.0.0.1:8008/post/", self.callback) 20 self.write('end') 21 22 def callback(self, response): 23 print response.body 24 25 settings = { 26 'template_path': 'template', 27 'static_path': 'static', 28 'static_url_prefix': '/static/', 29 'ui_methods': mt, 30 'ui_modules': md, 31 } 32 33 application = tornado.web.Application([ 34 (r"/index", MainHandler), 35 ], **settings) 36 37 38 if __name__ == "__main__": 39 application.listen(8009) 40 tornado.ioloop.IOLoop.instance().start() 异步非阻塞例子

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。

 

1 #!/usr/bin/env python 2 2 # -*- coding:utf-8 -*- 3 3 4 4 import tornado.ioloop 5 5 import tornado.web 6 6 7 7 8 8 class MainHandler(tornado.web.RequestHandler): 9 9 def get(self): 10 10 self.write("Hello, world") 11 11 12 12 class StoryHandler(tornado.web.RequestHandler): 13 13 def get(self, story_id): 14 14 self.write("You requested the story " + story_id) 15 15 16 16 class BuyHandler(tornado.web.RequestHandler): 17 17 def get(self): 18 18 self.write("buy.xxx.com/index") 19 19 20 20 application = tornado.web.Application([ 21 21 ("/index", MainHandler), 22 22 ("/story/([0-9]+)", StoryHandler), 23 23 ]) 24 24 25 25 application.add_handlers('buy.xxx.com$', [ 26 26 ('/index',BuyHandler), 27 27 ]) 28 28 29 29 if __name__ == "__main__": 30 30 application.listen(80) 31 31 tornado.ioloop.IOLoop.instance().start() View Code

 

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 ifforwhile 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。

1 <!DOCTYPE html> 2 <html> 3 <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> 5 <link href="{{static_url("css/common.css")}}" rel="stylesheet" /> 6 {% block CSS %}{% end %} 7 </head> 8 <body> 9 10 <div class="pg-header"> 11 12 </div> 13 14 {% block RenderBody %}{% end %} 15 16 <script src="{{static_url("js/jquery-3.4.1.js")}}"></script> 17 18 {% block JavaScript %}{% end %} 19 </body> 20 </html> layout.html 1 {% extends 'layout.html'%} 2 {% block CSS %} 3 <link href="{{static_url("css/index.css")}}" rel="stylesheet" /> 4 {% end %} 5 6 {% block RenderBody %} 7 <h1>Index</h1> 8 9 <ul> 10 {% for item in li %} 11 <li>{{item}}</li> 12 {% end %} 13 </ul> 14 15 {% end %} 16 17 {% block JavaScript %} 18 19 {% end %} index.html 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 7 8 class MainHandler(tornado.web.RequestHandler): 9 def get(self): 10 self.render('home/index.html') 11 12 settings = { 13 'template_path': 'template', 14 } 15 16 application = tornado.web.Application([ 17 (r"/index", MainHandler), 18 ], **settings) 19 20 21 if __name__ == "__main__": 22 application.listen(80) 23 tornado.ioloop.IOLoop.instance().start() xxx.py

在模板中默认提供了一些函数、字段、类以供模板使用:

  • escapetornado.escape.xhtml_escape 的別名
  • xhtml_escapetornado.escape.xhtml_escape 的別名
  • url_escapetornado.escape.url_escape 的別名
  • json_encodetornado.escape.json_encode 的別名
  • squeezetornado.escape.squeeze 的別名
  • linkifytornado.escape.linkify 的別名
  • datetime: Python 的 datetime 模组
  • handler: 当前的 RequestHandler 对象
  • requesthandler.request 的別名
  • current_userhandler.current_user 的別名
  • localehandler.locale 的別名
  • _handler.locale.translate 的別名
  • static_url: for handler.static_url 的別名
  • xsrf_form_htmlhandler.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

1 # uimethods.py 2 3 def tab(self): 4 return 'UIMethod' uimethods.py 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 from tornado.web import UIModule 4 from tornado import escape 5 6 class custom(UIModule): 7 8 def render(self, *args, **kwargs): 9 return escape.xhtml_escape('<h1>xxx</h1>') 10 #return escape.xhtml_escape('<h1>xxx</h1>') uimodules.py

2、注册

1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 from tornado.escape import linkify 7 import uimodules as md 8 import uimethods as mt 9 10 class MainHandler(tornado.web.RequestHandler): 11 def get(self): 12 self.render('index.html') 13 14 settings = { 15 'template_path': 'template', 16 'static_path': 'static', 17 'static_url_prefix': '/static/', 18 'ui_methods': mt, 19 'ui_modules': md, 20 } 21 22 application = tornado.web.Application([ 23 (r"/index", MainHandler), 24 ], **settings) 25 26 27 if __name__ == "__main__": 28 application.listen(8009) 29 tornado.ioloop.IOLoop.instance().start() main.py

3、使用

1 <!DOCTYPE html> 2 <html> 3 <head lang="en"> 4 <meta charset="UTF-8"> 5 <title></title> 6 <link href="{{static_url("commons.css")}}" rel="stylesheet" /> 7 </head> 8 <body> 9 <h1>hello</h1> 10 {% module custom(123) %} 11 {{ tab() }} 12 </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。

1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 7 8 class MainHandler(tornado.web.RequestHandler): 9 def get(self): 10 self.render('home/index.html') 11 12 settings = { 13 'template_path': 'template', 14 'static_path': 'static', 15 'static_url_prefix': '/static/', 16 } 17 18 application = tornado.web.Application([ 19 (r"/index", MainHandler), 20 ], **settings) 21 22 23 if __name__ == "__main__": 24 application.listen(80) 25 tornado.ioloop.IOLoop.instance().start() main.py 1 <!DOCTYPE html> 2 <html> 3 <head lang="en"> 4 <meta charset="UTF-8"> 5 <title></title> 6 <link href="{{static_url("commons.css")}}" rel="stylesheet" /> 7 </head> 8 <body> 9 <h1>hello</h1> 10 </body> 11 </html> index.html 1 def get_content_version(cls, abspath): 2 """Returns a version string for the resource at the given path. 3 4 This class method may be overridden by subclasses. The 5 default implementation is a hash of the file's contents. 6 7 .. versionadded:: 3.1 8 """ 9 data = cls.get_content(abspath) 10 hasher = hashlib.md5() 11 if isinstance(data, bytes): 12 hasher.update(data) 13 else: 14 for chunk in data: 15 hasher.update(chunk) 16 return hasher.hexdigest() 静态文件缓存的实现

2、csrf

Tornado和Django中的相似,跨站伪造请求(Cross-site request forgery)

1 settings = { 2 "xsrf_cookies": True, 3 } 4 application = tornado.web.Application([ 5 (r"/", MainHandler), 6 (r"/login", LoginHandler), 7 ], **settings) 配置 1 <form action="/new_message" method="post"> 2 {{ xsrf_form_html() }} 3 <input type="text" name="message"/> 4 <input type="submit" value="Post"/> 5 </form> 普通表单 1 function getCookie(name) { 2 var r = document.cookie.match("\\b" + name + "=([^;]*)\\b"); 3 return r ? r[1] : undefined; 4 } 5 6 jQuery.postJSON = function(url, args, callback) { 7 args._xsrf = getCookie("_xsrf"); 8 $.ajax({url: url, data: $.param(args), dataType: "text", type: "POST", 9 success: function(response) { 10 callback(eval("(" + response + ")")); 11 }}); 12 }; 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。

1 class MainHandler(tornado.web.RequestHandler): 2 def get(self): 3 if not self.get_cookie("mycookie"): 4 self.set_cookie("mycookie", "myvalue") 5 self.write("Your cookie was not set yet!") 6 else: 7 self.write("Your cookie was set!") 基本使用

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

1 class MainHandler(tornado.web.RequestHandler): 2 def get(self): 3 if not self.get_secure_cookie("mycookie"): 4 self.set_secure_cookie("mycookie", "myvalue") 5 self.write("Your cookie was not set yet!") 6 else: 7 self.write("Your cookie was set!") 8 9 application = tornado.web.Application([ 10 (r"/", MainHandler), 11 ], cookie_secret="61oETzKXQAGaYdkL5gEmGeJJFuYh7EQnp2XdTP1o/Vo=") View Code 1 def _create_signature_v1(secret, *parts): 2 hash = hmac.new(utf8(secret), digestmod=hashlib.sha1) 3 for part in parts: 4 hash.update(utf8(part)) 5 return utf8(hash.hexdigest()) 6 7 8 def _create_signature_v2(secret, s): 9 hash = hmac.new(utf8(secret), digestmod=hashlib.sha256) 10 hash.update(utf8(s)) 11 return utf8(hash.hexdigest()) 内部算法 1 def create_signed_value(secret, name, value, version=None, clock=None, 2 key_version=None): 3 if version is None: 4 version = DEFAULT_SIGNED_VALUE_VERSION 5 if clock is None: 6 clock = time.time 7 8 timestamp = utf8(str(int(clock()))) 9 value = base64.b64encode(utf8(value)) 10 if version == 1: 11 signature = _create_signature_v1(secret, name, value, timestamp) 12 value = b"|".join([value, timestamp, signature]) 13 return value 14 elif version == 2: 15 # The v2 format consists of a version number and a series of 16 # length-prefixed fields "%d:%s", the last of which is a 17 # signature, all separated by pipes. All numbers are in 18 # decimal format with no leading zeros. The signature is an 19 # HMAC-SHA256 of the whole string up to that point, including 20 # the final pipe. 21 # 22 # The fields are: 23 # - format version (i.e. 2; no length prefix) 24 # - key version (integer, default is 0) 25 # - timestamp (integer seconds since epoch) 26 # - name (not encoded; assumed to be ~alphanumeric) 27 # - value (base64-encoded) 28 # - signature (hex-encoded; no length prefix) 29 def format_field(s): 30 return utf8("%d:" % len(s)) + utf8(s) 31 to_sign = b"|".join([ 32 b"2", 33 format_field(str(key_version or 0)), 34 format_field(timestamp), 35 format_field(name), 36 format_field(value), 37 b'']) 38 39 if isinstance(secret, dict): 40 assert key_version is not None, 'Key version must be set when sign key dict is used' 41 assert version >= 2, 'Version must be at least 2 for key version support' 42 secret = secret[key_version] 43 44 signature = _create_signature_v2(secret, to_sign) 45 return to_sign + signature 46 else: 47 raise ValueError("Unsupported version %d" % version) 加密 1 def _decode_signed_value_v1(secret, name, value, max_age_days, clock): 2 parts = utf8(value).split(b"|") 3 if len(parts) != 3: 4 return None 5 signature = _create_signature_v1(secret, name, parts[0], parts[1]) 6 if not _time_independent_equals(parts[2], signature): 7 gen_log.warning("Invalid cookie signature %r", value) 8 return None 9 timestamp = int(parts[1]) 10 if timestamp < clock() - max_age_days * 86400: 11 gen_log.warning("Expired cookie %r", value) 12 return None 13 if timestamp > clock() + 31 * 86400: 14 # _cookie_signature does not hash a delimiter between the 15 # parts of the cookie, so an attacker could transfer trailing 16 # digits from the payload to the timestamp without altering the 17 # signature. For backwards compatibility, sanity-check timestamp 18 # here instead of modifying _cookie_signature. 19 gen_log.warning("Cookie timestamp in future; possible tampering %r", 20 value) 21 return None 22 if parts[1].startswith(b"0"): 23 gen_log.warning("Tampered cookie %r", value) 24 return None 25 try: 26 return base64.b64decode(parts[0]) 27 except Exception: 28 return None 29 30 31 def _decode_fields_v2(value): 32 def _consume_field(s): 33 length, _, rest = s.partition(b':') 34 n = int(length) 35 field_value = rest[:n] 36 # In python 3, indexing bytes returns small integers; we must 37 # use a slice to get a byte string as in python 2. 38 if rest[n:n + 1] != b'|': 39 raise ValueError("malformed v2 signed value field") 40 rest = rest[n + 1:] 41 return field_value, rest 42 43 rest = value[2:] # remove version number 44 key_version, rest = _consume_field(rest) 45 timestamp, rest = _consume_field(rest) 46 name_field, rest = _consume_field(rest) 47 value_field, passed_sig = _consume_field(rest) 48 return int(key_version), timestamp, name_field, value_field, passed_sig 49 50 51 def _decode_signed_value_v2(secret, name, value, max_age_days, clock): 52 try: 53 key_version, timestamp, name_field, value_field, passed_sig = _decode_fields_v2(value) 54 except ValueError: 55 return None 56 signed_string = value[:-len(passed_sig)] 57 58 if isinstance(secret, dict): 59 try: 60 secret = secret[key_version] 61 except KeyError: 62 return None 63 64 expected_sig = _create_signature_v2(secret, signed_string) 65 if not _time_independent_equals(passed_sig, expected_sig): 66 return None 67 if name_field != utf8(name): 68 return None 69 timestamp = int(timestamp) 70 if timestamp < clock() - max_age_days * 86400: 71 # The signature has expired. 72 return None 73 try: 74 return base64.b64decode(value_field) 75 except Exception: 76 return None 77 78 79 def get_signature_key_version(value): 80 value = utf8(value) 81 version = _get_version(value) 82 if version < 2: 83 return None 84 try: 85 key_version, _, _, _, _ = _decode_fields_v2(value) 86 except ValueError: 87 return None 88 89 return key_version 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。

1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 7 8 class MainHandler(tornado.web.RequestHandler): 9 10 def get(self): 11 login_user = self.get_secure_cookie("login_user", None) 12 if login_user: 13 self.write(login_user) 14 else: 15 self.redirect('/login') 16 17 18 class LoginHandler(tornado.web.RequestHandler): 19 def get(self): 20 self.current_user() 21 22 self.render('login.html', **{'status': ''}) 23 24 def post(self, *args, **kwargs): 25 26 username = self.get_argument('name') 27 password = self.get_argument('pwd') 28 if username == 'ssss' and password == '123': 29 self.set_secure_cookie('login_user', 'sss') 30 self.redirect('/') 31 else: 32 self.render('login.html', **{'status': '用户名或密码错误'}) 33 34 settings = { 35 'template_path': 'template', 36 'static_path': 'static', 37 'static_url_prefix': '/static/', 38 'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh' 39 } 40 41 application = tornado.web.Application([ 42 (r"/index", MainHandler), 43 (r"/login", LoginHandler), 44 ], **settings) 45 46 47 if __name__ == "__main__": 48 application.listen(8888) 49 tornado.ioloop.IOLoop.instance().start() cookie用户验证 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 7 class BaseHandler(tornado.web.RequestHandler): 8 9 def get_current_user(self): 10 return self.get_secure_cookie("login_user") 11 12 class MainHandler(BaseHandler): 13 14 @tornado.web.authenticated 15 def get(self): 16 login_user = self.current_user 17 self.write(login_user) 18 19 20 21 class LoginHandler(tornado.web.RequestHandler): 22 def get(self): 23 self.current_user() 24 25 self.render('login.html', **{'status': ''}) 26 27 def post(self, *args, **kwargs): 28 29 username = self.get_argument('name') 30 password = self.get_argument('pwd') 31 if username == 'ssss' and password == '123': 32 self.set_secure_cookie('login_user', 'sss') 33 self.redirect('/') 34 else: 35 self.render('login.html', **{'status': '用户名或密码错误'}) 36 37 settings = { 38 'template_path': 'template', 39 'static_path': 'static', 40 'static_url_prefix': '/static/', 41 'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh', 42 'login_url': '/login' 43 } 44 45 application = tornado.web.Application([ 46 (r"/index", MainHandler), 47 (r"/login", LoginHandler), 48 ], **settings) 49 50 51 if __name__ == "__main__": 52 application.listen(8888) 53 tornado.ioloop.IOLoop.instance().start() tonado内部提供 cookie的用户验证

五、扩展功能

1、自定义Session

1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 class Foo(object): 5 6 def __getitem__(self, key): 7 print '__getitem__',key 8 9 def __setitem__(self, key, value): 10 print '__setitem__',key,value 11 12 def __delitem__(self, key): 13 print '__delitem__',key 14 15 16 17 obj = Foo() 18 result = obj['k1'] 19 #obj['k2'] = 'ssss' 20 #del obj['k1'] 储备 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 from hashlib import sha1 7 import os, time 8 9 session_container = {} 10 11 create_session_id = lambda: sha1('%s%s' % (os.urandom(16), time.time())).hexdigest() 12 13 14 class Session(object): 15 16 session_id = "__sessionId__" 17 18 def __init__(self, request): 19 session_value = request.get_cookie(Session.session_id) 20 if not session_value: 21 self._id = create_session_id() 22 else: 23 self._id = session_value 24 request.set_cookie(Session.session_id, self._id) 25 26 def __getitem__(self, key): 27 return session_container[self._id][key] 28 29 def __setitem__(self, key, value): 30 if session_container.has_key(self._id): 31 session_container[self._id][key] = value 32 else: 33 session_container[self._id] = {key: value} 34 35 def __delitem__(self, key): 36 del session_container[self._id][key] 37 38 39 class BaseHandler(tornado.web.RequestHandler): 40 41 def initialize(self): 42 # my_session['k1']访问 __getitem__ 方法 43 self.my_session = Session(self) 44 45 46 class MainHandler(BaseHandler): 47 48 def get(self): 49 print self.my_session['c_user'] 50 print self.my_session['c_card'] 51 self.write('index') 52 53 class LoginHandler(BaseHandler): 54 55 def get(self): 56 self.render('login.html', **{'status': ''}) 57 58 def post(self, *args, **kwargs): 59 60 username = self.get_argument('name') 61 password = self.get_argument('pwd') 62 if username == 'sss' and password == '123': 63 64 self.my_session['c_user'] = 'sss' 65 self.my_session['c_card'] = '12312312309823012' 66 67 self.redirect('/index') 68 else: 69 self.render('login.html', **{'status': '用户名或密码错误'}) 70 71 settings = { 72 'template_path': 'template', 73 'static_path': 'static', 74 'static_url_prefix': '/static/', 75 'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh', 76 'login_url': '/login' 77 } 78 79 application = tornado.web.Application([ 80 (r"/index", MainHandler), 81 (r"/login", LoginHandler), 82 ], **settings) 83 84 85 if __name__ == "__main__": 86 application.listen(8888) 87 tornado.ioloop.IOLoop.instance().start() session实现机制

 

# 一致性哈希 #!/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 """ # session 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框架

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Django中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 1 #!/usr/bin/env python 2 # -*- coding:utf-8 -*- 3 4 import tornado.ioloop 5 import tornado.web 6 from hashlib import sha1 7 import os, time 8 import re 9 10 11 class MainForm(object): 12 def __init__(self): 13 self.host = "(.*)" 14 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}$" 15 self.port = '(\d+)' 16 self.phone = '^1[3|4|5|8][0-9]\d{8}$' 17 18 def check_valid(self, request): 19 form_dict = self.__dict__ 20 for key, regular in form_dict.items(): 21 post_value = request.get_argument(key) 22 # 让提交的数据 和 定义的正则表达式进行匹配 23 ret = re.match(regular, post_value) 24 print key,ret,post_value 25 26 27 class MainHandler(tornado.web.RequestHandler): 28 def get(self): 29 self.render('index.html') 30 def post(self, *args, **kwargs): 31 obj = MainForm() 32 result = obj.check_valid(self) 33 self.write('ok') 34 35 36 37 settings = { 38 'template_path': 'template', 39 'static_path': 'static', 40 'static_url_prefix': '/static/', 41 'cookie_secret': 'aiuasdhflashjdfoiuashdfiuh', 42 'login_url': '/login' 43 } 44 45 application = tornado.web.Application([ 46 (r"/index", MainHandler), 47 ], **settings) 48 49 50 if __name__ == "__main__": 51 application.listen(8888) 52 tornado.ioloop.IOLoop.instance().start() py # 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 #!/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

 

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