tornado之Hello world

#!/usr/bin/env python26
#-*- coding:utf8 -*-

import tornado.httpserver
import tornado.ioloop
import tornado.options
import tornado.web

from tornado.options import define,options
define("port",default=8000,help="run on this port",type=int)

class TestHandler(tornado.web.RequestHandler):
        def get(self):
                self.write("Hello world!")
                greeting=self.get_argument('greeting','Hello')
                self.write(greeting+',friendly user!\n')

                print "*"*30

def main():
        tornado.options.parse_command_line()

        app=tornado.web.Application(handler=[(r"/",TestHandler)])

        http_server=tornado.httpserver.HTTPServer(app)

        try:
                http_server.listen(options.port)
                tornado.ioloop.IOLoop.instance().start()
        except KeyboardInterrupt,e:
                print e

if __name__ == "__main__":
        main()

上述的脚本在测试过程中，通过print发现没有输出，断定原因在于get函数没有被调用

对比之前写的代码，原来是这里写错了

app=tornado.web.Application(handlers=[(r"/",TestHandler)])

tornado.web.Application = class Application(__builtin__.object)
 |  A collection of request handlers that make up a web application.
 |
 |  Instances of this class are callable and can be passed directly to
 |  HTTPServer to serve the application::
 |
 |      application = web.Application([
 |          (r"/", MainPageHandler),
 |      ])
 |      http_server = httpserver.HTTPServer(application)
 |      http_server.listen(8080)
 |      ioloop.IOLoop.instance().start()

通过帮助文档中没有查到默认参数名是handlers，不过测试可以发现确实如此，后续可以不加上。

【参考资料】

1、http://demo.pythoner.com/itt2zh/ch6.html