python 之 ConfigParser module简用说明
在使用IMAP4作登陆邮箱时涉及到要不要使用明文密码的问题，其中一种方法是通过读取配置文件来获取用户名和密码。读取配置文件有一块相关的模块是 ConfigParser module，下面简单记录下其调用方法；
#!/usr/bin/env python
#-*- coding: utf-8 -*-
#filename:config_parser_.py
import ConfigParser
cf = ConfigParser.ConfigParser()#初始化实例
content = cf.read('config.txt')#读取配置文件
print 'content:\n %s' % content
sections = cf.sections()#读取【】中的section内容
print 'sections:\n %s' % sections
options = cf.options('db')#获取对应section下的option 即：db
print 'options:\n %s' % options
items = cf.items('db')#获取指定section的配置信息
print 'items:\n %s' % items
db_host = cf.get('db', 'db_host')#可以按照指定类型获取option的信息
db_port = cf.getint('db', 'db_port')#比如整形
db_user = cf.get('db', 'db_user')
db_pass = cf.get('db','db_pass')
concurrent_test = cf.get('concurrent', 'thread')
print 'db_host:%s' % db_host
print 'db_port:%s' % db_port
print 'db_user:%s' % db_user
print 'db_pass:%s' % db_pass
print 'concurrent_test:\n %s' % concurrent_test
cf.set('db', 'db_test', 'test2')#设置option的值，可以重写
cf.write(open('config.txt', 'w'))#需要写回保存
items = cf.items('db')
print 'After the set, items changed to :\n %s' % items
cf.add_section('new')#追加新的section
cf.set('new', 'int', '555')#设置option值
cf.set('new', 'str', 'python is python')
cf.write(open('config.txt', 'w'))
items = cf.items('new')
print 'After the add, items changed to :\n %s' % items
cf.remove_option('new', 'int')#移除section为new中的其中option值
items = cf.items('new')
cf.write(open('config.txt', 'w'))#需要写回保存
print 'After the option remove, items changed to :\n %s' % items
cf.remove_section('new')#移除整个section
items = cf.items('new')
cf.write(open('config.txt', 'w'))
print 'After the section remove, items changed to :\n %s' % items
原始config.txt文件：
[db] db_host = 127.0.0.1 db_port = 22 db_user = root db_pass = passwd db_test = 23453456465 [concurrent] thread = 10 processor = 20
输出：
>>> ================================ RESTART ================================
>>>
content:
['config.txt']
sections:
['db', 'concurrent']
options:
['db_host', 'db_port', 'db_user', 'db_pass', 'db_test']
items:
[('db_host', '127.0.0.1'), ('db_port', '22'), ('db_user', 'root'), ('db_pass', 'passwd'), ('db_test', '23453456465')]
#可以按照指定类型获取option的信息，cf.getint（）
db_host:127.0.0.1
db_port:22
db_user:root
db_pass:passwd
concurrent_test:
10
After the set, items changed to :
[('db_host', '127.0.0.1'), ('db_port', '22'), ('db_user', 'root'), ('db_pass', 'passwd'), ('db_test', 'test2')]
After the add, items changed to :
[('int', '555'), ('str', 'python is python')]
After the option remove, items changed to :
[('str', 'python is python')]#int被移除了
Traceback (most recent call last):#这里报错很正常，因为理论上new这个section已经remove了，所以找不到
File "D:\Python\tmp\config_parser_.py", line 50, in <module>
items = cf.items('new')
File "C:\Python27\lib\ConfigParser.py", line 634, in items
raise NoSectionError(section)
NoSectionError: No section: 'new'
>>>
修改后的config.txt文件内容
[db] db_host = 127.0.0.1 db_port = 22 db_user = root db_pass = passwd db_test = test2 [concurrent] thread = 10 processor = 20 [new]#这个理论上已经移除，但是仍存在，比较奇怪？？？？？why? str = python is python
实例应用：
#!/usr/bin/env python
#-*- coding: utf-8 -*-
#filename:receive_imap_email.py
import imaplib, os, ConfigParser
def user_login(verbose=False):
#Read the config file
config = ConfigParser.ConfigParser()
config.read(r'D:\Python\tmp\config.txt')#从本配置文件中读取
#Connect to the server
hostname = config.get('server', 'hostname')#获取server下的hostname
if verbose:
print 'Connecting to', hostname
m = imaplib.IMAP4(hostname)
#Login to the account
username = config.get('account', 'username')#获取account下的username和passwd
passwd = config.get('account', 'passwd')
if verbose:
print 'Logging in as ', username
m.login(username,passwd)
print m.select()
print m.check()#检查邮件
m.close()
m.logout()
user_login(verbose=True)
config.txt文件内容：
[account] username = dxx_study passwd = xue***** [server] hostname = imap.163.com
输出：
>>> ================================ RESTART ================================
>>>
Connecting to imap.163.com
Logging in as dxx_study
('OK', ['175'])
('OK', ['CHECK completed'])
>>>
这种应该在有大量用户的情况下使用配置文件估计比较好，免得一个个输入或者在程序中占用大量位置，修改也比较方便；
参考文章：http://blog.chinaunix.net/uid-25890465-id-3312861.html