tornado | 易学教程

[原]tornado源码分析系列（六）[HTTPServer详解]

阅读更多关于 [原]tornado源码分析系列（六）[HTTPServer详解]

引言：上一章讲了关于HTTPServer的原理，这一次通过分析源码来了解更多的细节看看HTTPServer类的组织结构： HTTPServer的主要工作一.提供了一些基础的比如说listen,bind此类共有操作二.完成了一个 _handle_events()的公有回调函数，此函数是 IOLoop的基础，此函数为每一个连接创建一个单独的 IOStream 对象三.start函数，启动HTTPServer,并设置相应的参数（如根据CPU个数来设置进程数等）从HTTPServer类的构造函数可以看出，最重要的参数是设置回调函数，此回调函数用于处理request对象每次有HTTP的请求，都会通过HTTPConnection 封装一个HTTPRequest对象，这个对象包含了HTTP请求的所有信息所以在HTTPServer层，需要对这个对象进行一番处理后调用 request.write将结果返回给客户端此回调函数会先注册到HTTPServer，然后注册到HTTPConnection 里面，因为request这个对象是由HTTPConnection对象产生 def _handle_events(self, fd, events): while True: try: connection, address = self._socket.accept() except

Unicode strings in tornado web app

阅读更多关于 Unicode strings in tornado web app

问题 How can I use unicode strings in tornado views or templates? I insert in template <meta http-equiv="content-type" content="text/html;charset=utf-8" /> And in view # - - coding: utf-8 - - Output is ???? 回答1: Once you have your unicode string ready, the request should end self.render("template.html", aString=aUnicodeString) This renders the file "template.html" setting the aString variable to aUnicodeString. template.html would look something like this: <html> <head> <meta http-equiv="Content

Tornado Post Method Not Found

阅读更多关于 Tornado Post Method Not Found

问题 I'm trying to post a form in Tornado web server but whenever I click submit the following error generates 405 Method Not Allowed Here is the form <form method="post"> First name: <input type="text" name="fname"><br> Last name: <input type="text" name="lname"><br> <input type="submit" value="Submit"> </form> I've tried changing the "get" method on the main Request Handler to "post" but it doesn't work. The only method that works is GET, class MainHandler(BaseHandler): """ Main request handler

Python Tornado - Confused how to convert a blocking function into a non-blocking function

阅读更多关于 Python Tornado - Confused how to convert a blocking function into a non-blocking function

问题 Suppose I have a long running function: def long_running_function(): result_future = Future() result = 0 for i in xrange(500000): result += i result_future.set_result(result) return result_future I have a get function in a handler that prints the user with the above result of a for loop that adds all the number in the xrange: @gen.coroutine def get(self): print "start" self.future = long_running_function() message = yield self.future self.write(str(message)) print "end" If I run the above

Right way to “timeout” a Request in Tornado

阅读更多关于 Right way to “timeout” a Request in Tornado

问题 I managed to code a rather silly bug that would make one of my request handlers run a very slow DB query. Interesting bit is that I noticed that even long-after siege completed Tornado was still churning through requests (sometimes 90s later). (Comment --> I'm not 100% sure of the workings of Siege, but I'm fairly sure it closed the connection..) My question in two parts: - Does Tornado cancel request handlers when client closes the connection? - Is there a way to timeout request handlers in

standard way to handle user session in tornado

阅读更多关于 standard way to handle user session in tornado

问题 So, in order to avoid the "no one best answer" problem, I'm going to ask, not for the best way, but the standard or most common way to handle sessions when using the Tornado framework. That is, if we're not using 3rd party authentication (OAuth, etc.), but rather we have want to have our own Users table with secure cookies in the browser but most of the session info stored on the server, what is the most common way of doing this? I have seen some people using Redis, some people using their

Tornado coroutine

阅读更多关于 Tornado coroutine

问题 I am trying to learn tornado coroutines, but I have error using below code. Traceback (most recent call last): File "D:\projekty\tornado\env\lib\site-packages\tornado\web.py", line 1334, in _execute result = yield result File "D:\projekty\tornado\env\lib\site-packages\tornado\gen.py", line 628, in run value = future.result() File "D:\projekty\tornado\env\lib\site-packages\tornado\concurrent.py", line 109, in result raise_exc_info(self._exc_info) File "D:\projekty\tornado\env\lib\site-packages

Is Tornado really non-blocking?

阅读更多关于 Is Tornado really non-blocking?

问题 Tornado advertises itself as "a relatively simple, non-blocking web server framework" and was designed to solve the C10k problem. However, looking at their database wrapper, which wraps MySQLdb, I came across the following piece of code: def _execute(self, cursor, query, parameters): try: return cursor.execute(query, parameters) except OperationalError: logging.error("Error connecting to MySQL on %s", self.host) self.close() raise As far as I know calls to the MySQLdb, which is built on top

Synchronous v/s Asynchronous

阅读更多关于 Synchronous v/s Asynchronous

问题 I am trying to understand the basic example provided on the introduction page of tornado documentation. It has 2 blocks of code. The Synchronous one is fine for me, and I do understand it. But the asynchronous one is one I am not able to understand. Synchronous from tornado.httpclient import HTTPClient def synchronous_fetch(url): http_client = HTTPClient() response = http_client.fetch(url) return response.body Asynchronous from tornado.httpclient import AsyncHTTPClient def asynchronous_fetch

How use Django with Tornado web server?

阅读更多关于 How use Django with Tornado web server?

问题 How do I use Django with the Tornado web server? 回答1: it's very simple ( especially with django 1.4) . 1 - just build your django project( and apps ) and make sure it works fine. 2- create a new python file at the root folder ( same dir where you used django-admin.py startproject ) 3- then copy the code below , edit the os.environ['DJANGO_SETTINGS_MODULE'] line, and paste it in that new .py file. import os import tornado.httpserver import tornado.ioloop import tornado.wsgi import sys import