tornado框架——進階

時間 2019-11-30

原文原文鏈接

tornado框架——進階

自定義Session組件

Session

面向對象基礎

面向對象中經過索引的方式訪問對象，須要內部實現 __getitem__ 、__delitem__、__setitem__方法css

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']

Tornado擴展

Tornado框架中，默認執行Handler的get/post等方法以前默認會執行 initialize方法，因此能夠經過自定義的方式使得全部請求在處理前執行操做...html

class BaseHandler(tornado.web.RequestHandler):
   
    def initialize(self):  # 執行Handler的get/post等方法以前默認會執行
        self.xxoo = "wupeiqi"
   
   
class MainHandler(BaseHandler):
   
    def get(self):
        print(self.xxoo)
        self.write('index')
 
class IndexHandler(BaseHandler):
   
    def get(self):
        print(self.xxoo)
        self.write('index')

session

session其實就是定義在服務器端用於保存用戶回話的容器，其必須依賴cookie才能實現。node

import config
from hashlib import sha1
import os
import time

create_session_id = lambda: sha1(bytes('%s%s' % (os.urandom(16), time.time()), encoding='utf-8')).hexdigest()


class SessionFactory:

    @staticmethod
    def get_session_obj(handler):
        obj = None

        if config.SESSION_TYPE == "cache":
            obj = CacheSession(handler)
        elif config.SESSION_TYPE == "memcached":
            obj = MemcachedSession(handler)
        elif config.SESSION_TYPE == "redis":
            obj = RedisSession(handler)
        return obj


class CacheSession:
    session_container = {}
    session_id = "__sessionId__"

    def __init__(self, handler):
        self.handler = handler
        client_random_str = handler.get_cookie(CacheSession.session_id, None)
        if client_random_str and client_random_str in CacheSession.session_container:
            self.random_str = client_random_str
        else:
            self.random_str = create_session_id()
            CacheSession.session_container[self.random_str] = {}

        expires_time = time.time() + config.SESSION_EXPIRES
        handler.set_cookie(CacheSession.session_id, self.random_str, expires=expires_time)

    def __getitem__(self, key):
        ret = CacheSession.session_container[self.random_str].get(key, None)
        return ret

    def __setitem__(self, key, value):
        CacheSession.session_container[self.random_str][key] = value

    def __delitem__(self, key):
        if key in CacheSession.session_container[self.random_str]:
            del CacheSession.session_container[self.random_str][key]


class RedisSession:
    def __init__(self, handler):
        pass


class MemcachedSession:
    def __init__(self, handler):
        pass

分佈式Session

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 : 初始化的節點，其中包含節點已經節點對應的權重
                默認每個節點有32個虛擬節點
                對於權重，經過多建立虛擬節點來實現
                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('該節點已經存在.')
                self.ring[key] = node
                self._sorted_keys.append(key)
            
    def add_node(self,node):
        ''' 新建節點
        node : 要添加的節點，格式爲：{'host':'127.0.0.1:8002','weight':1}，其中第一個元素表示節點，第二個元素表示該節點的權重。
        '''
        node = node.get('host',None)
        if not node:
                raise Exception('節點的地址不能爲空.')
                
        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('該節點已經存在.')
            self.ring[key] = node
            self._sorted_keys.append(key)
        
    def remove_node(self,node):
        ''' 移除節點
        node : 要移除的節點 '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):
        '''獲取 string_key 所在的節點'''
        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):
        '''獲取 string_key 所在的節點的索引'''
        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

"""

異步非阻塞

基本使用

裝飾器 + Future 從而實現Tornado的異步非阻塞python

class AsyncHandler(tornado.web.RequestHandler):
 
    @gen.coroutine
    def get(self):
        future = Future()
        future.add_done_callback(self.doing)
        yield future
        # 或
        # tornado.ioloop.IOLoop.current().add_future(future,self.doing)
        # yield future
 
    def doing(self,*args, **kwargs):
        self.write('async')
        self.finish()

當發送GET請求時，因爲方法被@gen.coroutine裝飾且yield 一個 Future對象，那麼Tornado會等待，等待用戶向future對象中放置數據或者發送信號，若是獲取到數據或信號以後，就開始執行doing方法。異步非阻塞體如今當在Tornaod等待用戶向future對象中放置數據時，還能夠處理其餘請求。mysql

注意：在等待用戶向future對象中放置數據或信號時，此鏈接是不斷開的。git

同步阻塞和異步非阻塞對比

同步阻塞

class SyncHandler(tornado.web.RequestHandler):

    def get(self):
        self.doing()
        self.write('sync')

    def doing(self):
        time.sleep(10)

異步非阻塞

class AsyncHandler(tornado.web.RequestHandler):
    @gen.coroutine
    def get(self):
        future = Future()
        tornado.ioloop.IOLoop.current().add_timeout(time.time() + 5, self.doing)
        yield future


    def doing(self, *args, **kwargs):
        self.write('async')
        self.finish()

httpclient類庫

Tornado提供了httpclient類庫用於發送Http請求，其配合Tornado的異步非阻塞使用。github

import tornado.web
from tornado import gen
from tornado import httpclient
 
# 方式一：
class AsyncHandler(tornado.web.RequestHandler):
    @gen.coroutine
    def get(self, *args, **kwargs):
        print('進入')
        http = httpclient.AsyncHTTPClient()
        data = yield http.fetch("http://www.google.com")
        print('完事',data)
        self.finish('6666')
 
# 方式二：
# class AsyncHandler(tornado.web.RequestHandler):
#     @gen.coroutine
#     def get(self):
#         print('進入')
#         http = httpclient.AsyncHTTPClient()
#         yield http.fetch("http://www.google.com", self.done)
#
#     def done(self, response):
#         print('完事')
#         self.finish('666')
 
application = tornado.web.Application([
    (r"/async", AsyncHandler),
])
 
if __name__ == "__main__":
    application.listen(8888)
    tornado.ioloop.IOLoop.instance().start()

基於異步非阻塞和Tornado-MySQL實現用戶登陸示例

"""
須要先安裝支持異步操做Mysql的類庫： 
    Tornado-MySQL： https://github.com/PyMySQL/Tornado-MySQL#installation
    
    pip3 install Tornado-MySQL

"""

import tornado.web
from tornado import gen

import tornado_mysql
from tornado_mysql import pools

POOL = pools.Pool(
    dict(host='127.0.0.1', port=3306, user='root', passwd='123', db='cmdb'),
    max_idle_connections=1,
    max_recycle_sec=3)


@gen.coroutine
def get_user_by_conn_pool(user):
    cur = yield POOL.execute("SELECT SLEEP(%s)", (user,))
    row = cur.fetchone()
    raise gen.Return(row)


@gen.coroutine
def get_user(user):
    conn = yield tornado_mysql.connect(host='127.0.0.1', port=3306, user='root', passwd='123', db='cmdb',
                                       charset='utf8')
    cur = conn.cursor()
    # yield cur.execute("SELECT name,email FROM web_models_userprofile where name=%s", (user,))
    yield cur.execute("select sleep(10)")
    row = cur.fetchone()
    cur.close()
    conn.close()
    raise gen.Return(row)


class LoginHandler(tornado.web.RequestHandler):
    def get(self, *args, **kwargs):
        self.render('login.html')

    @gen.coroutine
    def post(self, *args, **kwargs):
        user = self.get_argument('user')
        data = yield gen.Task(get_user, user)
        if data:
            print(data)
            self.redirect('http://www.oldboyedu.com')
        else:
            self.render('login.html')


application = tornado.web.Application([
    (r"/login", LoginHandler),
])

if __name__ == "__main__":
    application.listen(8888)
    tornado.ioloop.IOLoop.instance().start()

加入Form組件

1.開源組件——Tyrion

Tyrion是一個基於Python實現的支持多個WEB框架的Form表單驗證組件，其完美的支持Tornado、Django、Flask、Bottle Web框架。Tyrion主要有兩大重要動能：web

表單驗證
生成HTML標籤
保留上次提交內容

對於表單驗證，告別書寫重複的正則表達式對用戶提交的數據進行驗證的工做，今後解放雙手，跟着我左手右手一個慢動做...正則表達式

對於生成HTML標籤，不在人工書寫html標籤，讓Tyrion幫你自動建立...redis

對於保留上次提交內容，因爲默認表單提交後頁面刷新，原來輸入的內容會清空，Tyrion能夠保留上次提交內容。

github：https://github.com/WuPeiqi/Tyrion

2.自定義表單驗證組件

在Web程序中每每包含大量的表單驗證的工做，如：判斷輸入是否爲空，是否符合規則。

html部分

<!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

python部分

#!/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)
            # 讓提交的數據 和 定義的正則表達式進行匹配
            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()

因爲驗證規則能夠代碼重用，因此能夠如此定義：

#!/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不能爲空', 'valid': 'IP格式錯誤'}
        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': '數字不能爲空', 'valid': '數字格式錯誤'}
        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不能爲空', 'valid': 'IP格式錯誤'}
        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': '數字不能爲空', 'valid': '數字格式錯誤'}
        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):
        """
        驗證用戶表單請求的數據
        :param form_obj: Form對象（Form派生類的對象）
        :param request: Http請求上下文（用於從請求中獲取用戶提交的值）
        :param depth: 對Form內容的深度的支持
        :param pre_key: Html中name屬性值的前綴（多層Form時，內部遞歸時設置，無需理會）
        :return: 是否驗證經過，True：驗證成功；False：驗證失敗
        """

        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):
                    # 獲取以key開頭的全部的值，以參數的形式傳至
                    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
                # 讓提交的數據 和 定義的正則表達式進行匹配
                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 "驗證結果：", obj.valid_status
        # print "符合驗證結果：", obj.value_dict
        # print "錯誤信息:"
        # 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()

以上內容均轉載及整理自武沛齊老師博客

http://www.cnblogs.com/wupeiqi/articles/5702910.html