Python全栈开发:web框架之tornado
概述
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。)
下载安装:
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pip3 install tornado 源码安装 https: / / pypi.python.org / packages / source / t / tornado / tornado - 4.3 .tar.gz |
框架使用
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() |
执行过程:
- 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
- # 异步非阻塞示例
#!/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()
- 异步非阻塞示例
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。
- #!/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()
Tornado中原生支持二级域名的路由,如:
三、模板引擎
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。
注:在使用模板前需要在setting中设置模板路径:"template_path" : "tpl"
1、基本使用
- #!/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", list_info = [11,22,33])
- application = tornado.web.Application([
- (r"/index", MainHandler),
- ])
- if __name__ == "__main__":
- application.listen(8888)
- tornado.ioloop.IOLoop.instance().start()
- app.py
- <!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" />
- </head>
- <body>
- <div>
- <ul>
- {% for item in list_info %}
- <li>{{item}}</li>
- {% end %}
- </ul>
- </div>
- <script src="{{static_url("js/jquery-1.8.2.min.js")}}"></script>
- </body>
- </html>
- index.html
- 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
- 其他方法
2、母版
- <!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
3、导入
- <div>
- <ul>
- <li>1024</li>
- <li>42区</li>
- </ul>
- </div>
- header.html
- <!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" />
- </head>
- <body>
- <div class="pg-header">
- {% include 'header.html' %}
- </div>
- <script src="{{static_url("js/jquery-1.8.2.min.js")}}"></script>
- </body>
- </html>
- index.html
4、自定义UIMethod以UIModule
a. 定义
- # uimethods.py
- def tab(self):
- return 'UIMethod'
- #!/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
b. 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()
c. 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>
四、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()
- app.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
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()
五、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、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!")
2、加密cookie(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=")
- 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())
- # 加密
- def _create_signature_v2(secret, s):
- hash = hmac.new(utf8(secret), digestmod=hashlib.sha256)
- hash.update(utf8(s))
- return utf8(hash.hexdigest())
- 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"2",
- 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)
- # 解密
- 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"0"):
- 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
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 == '123':
- 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()
- 基于Cookie实现用户验证-Demo
- #!/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 == '123':
- 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()
- 基于签名Cookie实现用户验证-Demo
3、JavaScript操作Cookie
由于Cookie保存在浏览器端,所以在浏览器端也可以使用JavaScript来操作Cookie。
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/* 设置cookie,指定秒数过期 */ function setCookie(name,value,expires){ var temp = []; var current_date = new Date(); current_date.setSeconds(current_date.getSeconds() + 5); document.cookie = name + "= " + value + ";expires=" + current_date.toUTCString(); } |
对于参数:
- domain 指定域名下的cookie
- path 域名下指定url中的cookie
- secure https使用
注:jQuery中也有指定的插件 jQuery Cookie 专门用于操作cookie,猛击这里
六、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)
- 配置
- settings = {
- "xsrf_cookies": True,
- }
- application = tornado.web.Application([
- (r"/", MainHandler),
- (r"/login", LoginHandler),
- ], **settings)
- 配置
- 使用 - 普通表单
- <form action="/new_message" method="post">
- {{ xsrf_form_html() }}
- <input type="text" name="message"/>
- <input type="submit" value="Post"/>
- </form>
- 使用 - AJAX
- 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 + ")"));
- }});
- };
- 使用 - AJAX
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
七、上传文件
1、Form表单上传
- <!DOCTYPE html>
- <html>
- <head>
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
- <title>上传文件</title>
- </head>
- <body>
- <form id="my_form" name="form" action="/index" method="POST" enctype="multipart/form-data" >
- <input name="fff" id="my_file" type="file" />
- <input type="submit" value="提交" />
- </form>
- </body>
- </html>
- HTML
- #!/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
2、AJAX上传
- <!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 - XMLHttpRequest
- <!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 = $("#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);
- }
- })
- }
- </script>
- </body>
- </html>
- HTML - jQuery
- <!DOCTYPE html>
- <html>
- <head lang="en">
- <meta charset="UTF-8">
- <title></title>
- </head>
- <body>
- <form id="my_form" name="form" action="/index" method="POST" enctype="multipart/form-data" >
- <div id="main">
- <input name="fff" id="my_file" type="file" />
- <input type="button" name="action" value="Upload" onclick="redirect()"/>
- <iframe id='my_iframe' name='my_iframe' src="" class="hide"></iframe>
- </div>
- </form>
- <script>
- function redirect(){
- document.getElementById('my_iframe').onload = Testt;
- document.getElementById('my_form').target = 'my_iframe';
- document.getElementById('my_form').submit();
- }
- function Testt(ths){
- var t = $("#my_iframe").contents().find("body").text();
- console.log(t);
- }
- </script>
- </body>
- </html>
- HTML - iframe
- #!/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
- <script type="text/javascript">
- $(document).ready(function () {
- $("#formsubmit").click(function () {
- var iframe = $('<iframe name="postiframe" id="postiframe" style="display: none"></iframe>');
- $("body").append(iframe);
- var form = $('#theuploadform');
- form.attr("action", "/upload.aspx");
- form.attr("method", "post");
- form.attr("encoding", "multipart/form-data");
- form.attr("enctype", "multipart/form-data");
- form.attr("target", "postiframe");
- form.attr("file", $('#userfile').val());
- form.submit();
- $("#postiframe").load(function () {
- iframeContents = this.contentWindow.document.body.innerHTML;
- $("#textarea").html(iframeContents);
- });
- return false;
- });
- });
- </script>
- <form id="theuploadform">
- <input id="userfile" name="userfile" size="50" type="file" />
- <input id="formsubmit" type="submit" value="Send File" />
- </form>
- <div id="textarea">
- </div>
- 扩展:基于iframe实现Ajax上传示例
- $('#upload_iframe').load(function(){
- var iframeContents = this.contentWindow.document.body.innerText;
- iframeContents = JSON.parse(iframeContents);
- })
- function bindChangeAvatar1() {
- $('#avatarImg').change(function () {
- var file_obj = $(this)[0].files[0];
- $('#prevViewImg')[0].src = window.URL.createObjectURL(file_obj)
- })
- }
- function bindChangeAvatar2() {
- $('#avatarImg').change(function () {
- var file_obj = $(this)[0].files[0];
- var reader = new FileReader();
- reader.readAsDataURL(file_obj);
- reader.onload = function (e) {
- $('#previewImg')[0].src = this.result;
- };
- })
- }
- function bindChangeAvatar3() {
- $('#avatarImg').change(function () {
- var file_obj = $(this)[0].files[0];
- var form = new FormData();
- form.add('img_upload', file_obj);
- $.ajax({
- url: '',
- data: form,
- processData: false, // tell jQuery not to process the data
- contentType: false, // tell jQuery not to set contentType
- success: function (arg) {
- }
- })
- })
- }
- function bindChangeAvatar4() {
- $('#avatarImg').change(function () {
- $(this).parent().submit();
- $('#upload_iframe').load(function () {
- var iframeContents = this.contentWindow.document.body.innerText;
- iframeContents = JSON.parse(iframeContents);
- if (iframeContents.status) {
- $('#previewImg').attr('src', '/' + iframeContents.data);
- }
- })
- })
- }
- 其他
八、验证码
验证码原理在于后台自动创建一张带有随机内容的图片,然后将内容通过img标签输出到页面。
安装图像处理模块:
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pip3 install pillow |
示例截图:
验证码Demo源码下载:猛击这里
九、异步非阻塞
1、基本使用
装饰器 + Future 从而实现Tornado的异步非阻塞
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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() |
当发送GET请求时,由于方法被@gen.coroutine装饰且yield 一个 Future对象,那么Tornado会等待,等待用户向future对象中放置数据或者发送信号,如果获取到数据或信号之后,就开始执行doing方法。
异步非阻塞体现在当在Tornaod等待用户向future对象中放置数据时,还可以处理其他请求。
注意:在等待用户向future对象中放置数据或信号时,此连接是不断开的。
2、同步阻塞和异步非阻塞对比
- class SyncHandler(tornado.web.RequestHandler):
- def get(self):
- self.doing()
- self.write('sync')
- def doing(self):
- time.sleep(10)
- 同步阻塞
- 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()
- 异步非阻塞
3、httpclient类库
Tornado提供了httpclient类库用于发送Http请求,其配合Tornado的异步非阻塞使用。
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class AsyncHandler(tornado.web.RequestHandler): @gen .coroutine def get( self ): from tornado import httpclient http = httpclient.AsyncHTTPClient() yield http.fetch( "http://www.google.com" , self .endding) def endding( self , response): print ( len (response.body)) self .write( 'ok' ) self .finish() |
自定义Web组件
一、Session
1、面向对象基础
面向对象中通过索引的方式访问对象,需要内部实现 __getitem__ 、__delitem__、__setitem__方法。
- #!/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']
2、Tornado扩展
Tornado框架中,默认执行Handler的get/post等方法之前默认会执行 initialize方法,所以可以通过自定义的方式使得所有请求在处理前执行操作...
- class BaseHandler(tornado.web.RequestHandler):
- def initialize(self):
- 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')
3、session
session其实就是定义在服务器端用于保存用户回话的容器,其必须依赖cookie才能实现。
- #!/usr/bin/env python
- # -*- coding:utf-8 -*-
- 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
- 自定义Session
4、分布式Session
- #!/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
- """
- 一致性哈西
- 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
由于验证规则可以代码重用,所以可以如此定义:
- #!/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()
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