tornado的GET POST方法样品展示

2023-03-18 09:57:33

举例说明get和post该方法的用途：

一、演示样例用的GET方法:

import tornado.ioloop

import tornado.web

class MainHandler(tornado.web.RequestHandler):

def get(self):

self.write("Hello, world")

application = tornado.web.Application([

(r"/", MainHandler),

])

if __name__ == "__main__":

application.listen(8888)

tornado.ioloop.IOLoop.instance().start()

执行

# python tornado_example.py。

然后打开浏览器，输入http://ip:8888就看到页面输出Hello, world了。

二、GET&POST 代码

1. tornado-serv.py

#!/usr/bin/python

# File : tornado-serv.py

import torndb

import tornado.web

import tornado.ioloop

from tornado.options import define,options,parse_command_line

define('port',default=8888,help='run on the port',type=int)

database=torndb.Connection('localhost','talk',user='root',password='123456')

l=[]

class MainHandler(tornado.web.RequestHandler):

def get(self):

  self.render('example.html',title='Tornado GET&POST',items=l)

def post(self):

  count=1

  print(self.request.remote_ip)

  talk=self.get_argument('talk')

  talk=str(talk)

  database.execute('insert into chatting(id,content)
values(%d,"%s")'%(count,talk))

  l.append(talk)

  self.render('example.html',title='Tornado GET&POST',items=l)

def main():

parse_command_line()

app=tornado.web.Application(

  [(r'/',MainHandler),

  ],)

app.listen(options.port)

tornado.ioloop.IOLoop.instance().start()

if __name__=='__main__':

main()

2. example.html的内容例如以下：

<html>

  <head>

  <title>{{title}}</title>

  </head>

<body>

  <form name='input' action='/' method='post'>

  talk:

  <input type='text' name='talk'/>

  <input type='submit' value='send'/>

  </form>

  <ul>

{%for i in items%}

<li>{{escape(i)}}</li>

{%end%}

</ul>

</body>

</html>

三、数据库操作

以root帐号连接到mysqlserver：

# mysql -u root

假设提示找不到mysql文件，请尝试使用绝对路径，如本文演示样例为：

# /usr/local/mysql/bin/mysql -u root

命令成功运行后将进入到mysql命令提示符下：

1. 设置从本地主机登录的root帐号password：

mysql> set password for root@localhost=password('123456');

2. 创建"talk"数据库

mysql> create database talk;

3. 创建"chatting"表

mysql> use talk;

mysql> create table chatting(id int, content char(128));

4. 查看表

mysql> describe chatting;

+---------+-----------+------+-----+---------+-------+

| Field | Type | Null | Key | Default | Extra |

+---------+-----------+------+-----+---------+-------+

| id | int(11) | YES | | NULL | |

| content | char(128) | YES | | NULL | |

+---------+-----------+------+-----+---------+-------+

四、出错问题解决

1. 执行 tornado-serv.py时报错:

python tornado_serv.py

Traceback (most recent call last):

File "tornado_serv.py", line 6, in <module>

import torndb

ImportError: No module named torndb

解决:

须要安装 torndb

# pip install torndb

2. 执行 tornado-serv.py时报错:

Traceback (most recent call last):

File "tornado_serv.py", line 6, in <module>

import torndb

File "/usr/local/python2.7.3/lib/python2.7/site-packages/torndb.py", line 33, in <module>

import MySQLdb.constants

ImportError: No module named MySQLdb.constants

解决:

安装MySQL-python-1.2.3

# wget http://sourceforge.net/projects/mysql-python/files/mysql-python/1.2.3/MySQL-python-1.2.3.tar.gz/download

# tar zxf MySQL-python-1.2.3.tar.gz && cd MySQL-python-1.2.3

# python setup.py build

# python setup.py install

假设在运行python setup.py build时,报EnvironmentError: mysql_config not found的话,

先查找mysql_config的位置,使用

# find / -name mysql_config

我的是在/usr/local/mysql/bin/mysql_config,

然后改动MySQL-python-1.2.3文件夹下的site.cfg文件,

去掉mysql_config=XXX这行的凝视,并改成

mysql_config=/usr/local/mysql/bin/mysql_config,

以自己机器的为准.

假设没有找到，则表示你的server没有安装mysql,须要先安装。

再运行以下命令就能够了

python setup.py build

python setup.py install

3. 执行 python tornado_serv.py 时报错:

Traceback (most recent call last):

File "tornado_serv.py", line 6, in <module>

import torndb

File "/usr/local/python2.7.3/lib/python2.7/site-packages/torndb.py", line 33, in <module>

import MySQLdb.constants

File "build/bdist.linux-x86_64/egg/MySQLdb/__init__.py", line 19, in <module>

File "build/bdist.linux-x86_64/egg/_mysql.py", line 7, in <module>

File "build/bdist.linux-x86_64/egg/_mysql.py", line 6, in __bootstrap__

ImportError: libmysqlclient_r.so.15: cannot open shared object file: No such file or directory

解决:

查找动态库 libmysqlclient_r.so

# find / -name libmysqlclient_r.so

/usr/local/mysql/lib/mysql/libmysqlclient_r.so

将包括库的文件夹 /usr/local/mysql/lib/mysql

加入到库查找路径

# vim /etc/ld.so.conf

最后一行加入:

/usr/local/mysql/lib/mysql

【保存并退出】

# ldconfig

4. python tornado_serv.py

ERROR:root:Cannot connect to MySQL on localhost

Traceback (most recent call last):

File "/usr/local/python2.7.3/lib/python2.7/site-packages/torndb.py", line 96, in __init__

self.reconnect()

File "/usr/local/python2.7.3/lib/python2.7/site-packages/torndb.py", line 113, in reconnect

self._db = MySQLdb.connect(**self._db_args)

File "build/bdist.linux-x86_64/egg/MySQLdb/__init__.py", line 81, in Connect

return Connection(*args, **kwargs)

File "build/bdist.linux-x86_64/egg/MySQLdb/connections.py", line 187, in __init__

super(Connection, self).__init__(*args, **kwargs2)

OperationalError: (1045, "Access denied for user 'root'@'localhost' (using password: YES)")

解决:

是由于数据库没有设置并创建表；

五、页面測试

浏览器打开 "http://ip:8888" 的时候，发出 "GET"请求，请求根文件夹"/"，

依据tornado.web.Application中參数列表中元组对(r'/',MainHandler)。于是找到MainHandler类，

这个类继承了tornado.web.RequestHandler类。可是它里面未定义get和post方法（详细能够看源代码），

所以在MainHandler类中定义。

因为我仅仅在用户第一次訪问站点时处理get方法，

所以就是render example.html 就能够了。

之后传递数据全用 "POST" 方法，并把网页上输入的数据存放到数据库中。

浏览器显演示样例如以下：

数据库中显演示样例如以下：

mysql> select * from chatting;

+------+--------------------------+

| id | content |

+------+--------------------------+

| 1 | hello |

| 1 | who |

| 1 | this is |

| 1 | what are you doing |

| 1 | fet |

| 1 | this is my first version |

+------+--------------------------+

6 rows in set (0.00 sec)

终端显演示样例如以下：

[@ltv_13 python_study]# python tornado_serv.py

[I 140719 10:11:17 web:1811] 304 GET / (192.168.9.91)
3.42ms

192.168.9.91

[I 140719 10:11:20 web:1811] 200 POST / (192.168.9.91)
1.13ms

192.168.9.91

[I 140719 10:11:25 web:1811] 200 POST / (192.168.9.91)
0.85ms

192.168.9.91

[I 140719 10:11:35 web:1811] 200 POST / (192.168.9.91)
0.80ms

192.168.9.91

[I 140719 10:11:46 web:1811] 200 POST / (192.168.9.91)
0.82ms

192.168.9.91

[I 140719 10:11:51 web:1811] 200 POST / (192.168.9.91)
0.78ms

192.168.9.91

[I 140719 10:12:09 web:1811] 200 POST / (192.168.9.91)
0.99ms

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