1. 配置文件(ConfigParser模块)

1.1 ConfigParser简介

ConfigParser 是用来读取配置文件的包。配置文件的格式如下:中括号“[ ]”内包含的为section。section 下面为类似于key-value的options内容。例如

[db]
db_host = 127.0.0.1
db_port = 22
db_user = root
db_pass = rootroot

[concurrent]
thread = 10
processor = 20

 

1.2 ConfigParser 初始工作

使用ConfigParser 首选需要初始化实例,并读取配置文件:

import ConfigParser
cf = ConfigParser.ConfigParser()
cf.read("配置文件名")

 

1.3 ConfigParser函数

1.3.1. 获取所有sections

>>> s = cf.sections()
>>> print s
['db', 'concurrent']

1.3.2 获得指定section的options

>>> cf.options('db')
['db_host', 'db_port', 'db_user', 'db_pass']

1.3.3 获得指定sections的配置信息

>>> cf.items('db')
[('db_host', '127.0.0.1'), ('db_port', '22'), ('db_user', 'root'), ('db_pass', 'rootroot')]

1.3.4 获得指定sections的option的信息

>>> cf.get("db", "db_host")
'127.0.0.1'
>>> cf.getint("db", "db_port")
22

同样有getfloat、getboolean

以下注意:凡是改变文件内容的,都要最后写入。

1.3.5 设置某个option的值

>>> cf.set("db", "db_host", "127.1.1.1")
>>> cf.write(open("config.ini", 'w'))

写入后的文件内容为

[db]
db_host = 127.1.1.1
db_port = 22
db_user = root
db_pass = rootroot

[concurrent]
thread = 10
processor = 20

1.3.6 添加一个section

>>> cf.add_section("jihite")
>>> cf.set("jihite", "int", "15")
>>> cf.set("jihite", "bool", "True")
>>> cf.set("jihite", "float", "3.14")
>>> cf.write(open("config.ini", 'w'))

写入后的文件内容为

[db]
db_host = 127.1.1.1
db_port = 22
db_user = root
db_pass = rootroot

[concurrent]
thread = 10
processor = 20

[jihite]
int = 15
bool = True
float = 3.14

1.3.7 移除一个section

>>> cf.remove_option("jihite", "int")
True
>>> cf.write(open("config.ini", 'w'))

改变后的文件为

[db]
db_host = 127.1.1.1
db_port = 22
db_user = root
db_pass = rootroot

[concurrent]
thread = 10
processor = 20

[jihite]
bool = True
float = 3.14

1.3.8 移除一个option

>>> cf.remove_section("jihite")
True
>>> cf.write(open("config.ini", 'w'))

改变后的文件为

[db]
db_host = 127.1.1.1
db_port = 22
db_user = root
db_pass = rootroot

[concurrent]
thread = 10
processor = 20

1.4 ConfigParser举例

 

方式二:解析参数(argparse模块)

 

2. 解析参数(argparse模块)

2.1 argparse简介

argparse是python的命令行解析工具,它是Python标准库中推荐使用的编写命令行程序的工具。

 

2.2 argparser 初始工作

import argparse
parser = argparse.ArgumentParser()

类ArgumentParser定义为:

class ArgumentParser(prog=None, usage=None, description=None, epilog=None, parents=[], formatter_class=argparse.HelpFormatter, prefix_chars='-', fromfile_prefix_chars=None, argument_default=None, conflict_handler='error', add_help=True)

参数的含义为

2.2.1 prog:程序的名字,默认为sys.argv[0] 

>>> parser = argparse.ArgumentParser(prog="myprogram")
>>> parser.print_help()
usage: myprogram [-h]

optional arguments:
-h, --help show this help message and exit

2.2.2 usage: 描述程序用途的字符串

例子

del.py

import argparse
if __name__=="__main__":
parser = argparse.ArgumentParser()
parser.add_argument('content', help='content')
parser.add_argument('title', help='title')
parser.add_argument('tolist', help='tolist')
args = parser.parse_args()
content, title, tolist = args.content, args.title, args.tolist

mail=SMTP_SSL()
mail.sendMail(content, title, tolist)

执行

python2.7 del.py
usage: del.py [-h] content title tolist
del.py: error: too few arguments

2.2.3

更多参数

 

parser.add_argument("-v", "--verbose", help="increase output verbosity", action="store_true")
parser.add_argument('numbers', type=int, help="numbers to calculate", nargs='+')
parser.add_argument('-s', '--sum', help="sum all numbers", action='store_true', default=True)
parser.add_argument('-f', '--format', choices=['int', 'float'], help='choose result format', default='idsf')

更详细参考

 

2.3 添加参数选项


 

3. 综合实例

要求

1. 配置文件和输入参数两种方式,其中输入参数优先级高

2. 参数包括配置文件、下载目录、进程个数、日志文件、日志类型

3. 如果进程个数不知,那么默认为机器cpu核数

4. 如果参数类型不知,那么默认为3

def setArgs():
parse = argparse.ArgumentParser(prog = "down_v9.py", usage="%(prog)s [options]")
parse.add_argument("-c", "-config", type=str, help="配置文件")
parse.add_argument("-o", "-outdir", type=str, help="下载目录")
parse.add_argument("-p", "-processnum", type=int, help="进程个数")
parse.add_argument("-l", "-logfile", type=str, help="日志文件")
parse.add_argument("-lt", "-logtype", type=str, help="输出日志类型:1,只显示到屏幕;2,只输出到日志文件;3,即显示到屏幕又输出到日志文件")
args = parse.parse_args()
return args

def get_args():
args = setArgs()
config = args.c
outdir = args.o
process_num = args.p
logfile = args.l
logtype = args.lt

if config and os.path.isfile(config):
cf = ConfigParser.ConfigParser()
cf.read(config)
s = cf.sections()
if "con" in s:
cons = cf.options("con")
if outdir == None and "outdir" in cons:
outdir = cf.get("con", "outdir")
if process_num == None and "process_num" in cons:
process_num = cf.getint("con", "process_num")
if logfile == None and "logfile" in cons:
logfile = cf.get("con", "logfile")
if logtype == None and "logtype" in cons:
logtype = cf.get("con", "logtype")
if process_num == None:
process_num = multiprocessing.cpu_count()
if logtype == None:
logtype = 3

return