Python 理解OptionParser

understanding OptionParser

提问by MacUsers

I was trying out optparseand this is my initial script.

我正在尝试optparse，这是我的初始脚本。

#!/usr/bin/env python

import os, sys
from optparse import OptionParser

parser = OptionParser()
usage = "usage: %prog [options] arg1 arg2"

parser.add_option("-d", "--dir", type="string",
                  help="List of directory",
                  dest="inDir", default=".")

parser.add_option("-m", "--month", type="int",
                  help="Numeric value of the month", 
                  dest="mon")

options, arguments = parser.parse_args()

if options.inDir:
    print os.listdir(options.inDir)

if options.mon:
    print options.mon

def no_opt()
    print "No option has been given!!"

Now, this is what I'm trying to do:

现在，这就是我想要做的：

1. If no argument is given with the option, it will take the "default" value. i.e myScript.py -dwill just list the present directory or -mwithout any argument will take the current month as an argument.
2. For the "--month" only 01 to 12 are allowed as an argument
3. Want to combine more than one option for performing different tasks i.e. myScript.py -d this_dir -m 02will do different thing than -d and -m as individual.
4. It will print "No option has been given!!" ONLY if no option is supplied with the script.

1. 如果选项没有给出参数，它将采用“默认”值。即myScript.py -d只列出当前目录或-m不带任何参数将当前月份作为参数。
2. 对于“--month”，只允许 01 到 12 作为参数
3. 想要组合多个选项来执行不同的任务，即myScript.py -d this_dir -m 02会做与 -d 和 -m 不同的事情作为单独的。
4. 仅当脚本未提供任何选项时，它才会打印“ No option has been given!!”。

Are these doable? I did visit the doc.python.org site for possible answers, but as a python-beginner, I found myself lost in the pages. It's very much appreciated your help; thanks in advance. Cheers!!

这些可行吗？我确实访问了 doc.python.org 站点以获得可能的答案，但作为 Python 初学者，我发现自己迷失在这些页面中。非常感谢您的帮助；提前致谢。干杯！！

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Update: 16/01/11更新：16/01/11

I think I'm still missing something. This is the thing in my script now.

我想我仍然缺少一些东西。这就是我现在脚本中的内容。

parser = OptionParser()
usage = "usage: %prog [options] arg1 arg2"

parser.add_option("-m", "--month", type="string",
                  help="select month from  01|02|...|12",
                  dest="mon", default=strftime("%m"))

parser.add_option("-v", "--vo", type="string",
                  help="select one of the supported VOs",
                  dest="vos")

options, arguments = parser.parse_args()

These are my goal:

这些是我的目标：

1. run the script without any option, will return option.mon[working]
2. run the script with -m option, with return option.mon[working]
3. run the script with ONLY -v option, will ONLY return option.vos[not working at all]
4. run the script with -m and -v opting, will do different thing [yet to get to the point]

1. 不带任何选项运行脚本，将返回option.mon[ working]
2. 使用 -m 选项运行脚本，并返回option.mon[ working]
3. 使用 ONLY -v 选项运行脚本，只会返回option.vos[根本不工作]
4. 使用 -m 和 -v 选项运行脚本，会做不同的事情 [尚未达到重点]

When I run the script with only -m option, it's printing option.monfirst and then option.vos, which I don't want at all. Really appreciate if anyone can put me in the right direction. Cheers!!

当我只使用 -m 选项运行脚本时，它option.mon先打印，然后打印option.vos，我根本不想要。如果有人能让我朝着正确的方向前进，真的很感激。干杯！！

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3rd Update第三次更新

    #!/bin/env python

    from time import strftime
    from calendar import month_abbr
    from optparse import OptionParser

    # Set the CL options 
    parser = OptionParser()
    usage = "usage: %prog [options] arg1 arg2"

    parser.add_option("-m", "--month", type="string",
                      help="select month from  01|02|...|12", 
              dest="mon", default=strftime("%m"))

    parser.add_option("-u", "--user", type="string",
                      help="name of the user", 
              dest="vos")

    options, arguments = parser.parse_args()

    abbrMonth = tuple(month_abbr)[int(options.mon)]

    if options.mon:
        print "The month is: %s" % abbrMonth 

    if options.vos:
        print "My name is: %s" % options.vos 

    if options.mon and options.vos:
        print "I'm '%s' and this month is '%s'" % (options.vos,abbrMonth)

This is what the script returns when run with various options:

这是脚本在使用各种选项运行时返回的内容：

# ./test.py
The month is: Feb
#
# ./test.py -m 12
The month is: Dec
#
# ./test.py -m 3 -u Mac
The month is: Mar
My name is: Mac
I'm 'Mac' and this month is 'Mar'
#
# ./test.py -u Mac
The month is: Feb
My name is: Mac
I'm 'Mac' and this month is 'Feb'

I like to see only:

我只喜欢看：

 1. `I'm 'Mac' and this month is 'Mar'` - as *result #3*  
 2. `My name is: Mac` - as *result #4*

what am I doing wrong? Cheers!!

我究竟做错了什么？干杯！！

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4th Update:第四次更新：

Answering to myself: this way I can get what I'm looking for but I'm still not impressed though.

对自己回答：这样我就可以得到我想要的东西，但我仍然没有留下深刻的印象。

#!/bin/env python

import os, sys
from time import strftime
from calendar import month_abbr
from optparse import OptionParser

def abbrMonth(m):
    mn = tuple(month_abbr)[int(m)]
    return mn

# Set the CL options 
parser = OptionParser()
usage = "usage: %prog [options] arg1 arg2"

parser.add_option("-m", "--month", type="string",
                  help="select month from  01|02|...|12",
                  dest="mon")

parser.add_option("-u", "--user", type="string",
                  help="name of the user",
                  dest="vos")

(options, args) = parser.parse_args()

if options.mon and options.vos:
    thisMonth = abbrMonth(options.mon)
    print "I'm '%s' and this month is '%s'" % (options.vos, thisMonth)
    sys.exit(0)

if not options.mon and not options.vos:
    options.mon = strftime("%m")

if options.mon:
    thisMonth = abbrMonth(options.mon)
    print "The month is: %s" % thisMonth

if options.vos:
    print "My name is: %s" % options.vos

and now this gives me exactly what I was looking for:

现在这给了我我正在寻找的东西：

# ./test.py 
The month is: Feb

# ./test.py -m 09
The month is: Sep

# ./test.py -u Mac
My name is: Mac

# ./test.py -m 3 -u Mac
I'm 'Mac' and this month is 'Mar'

Is this the only way of doing so? Doesn't look the "best way" to me. Cheers!!

这是唯一的方法吗？对我来说看起来不是“最佳方式”。干杯！！

回答by ninjagecko

optparseis deprecated; you should use argparsein both python2 and python3

optparse已弃用；你应该argparse在 python2 和 python3 中使用

http://docs.python.org/library/argparse.html#module-argparse

http://docs.python.org/library/argparse.html#module-argparse

回答by jrennie

Your solution looks reasonable to me. Comments:

你的解决方案在我看来是合理的。注释：

• I don't understand why you turn month_abbrinto a tuple; it should work fine without the tuple()
• I'd recommend checking for invalid month value (raise OptionValueErrorif you find a problem)
• if you really want the user to input exactly "01", "02", ..., or "12", you could use the "choice" option type; see option types documentation

• 我不明白为什么你变成month_abbr了一个元组；没有它应该可以正常工作tuple()
• 我建议检查无效的月份值（raise OptionValueError如果您发现问题）
• 如果您确实希望用户准确输入“01”、“02”、...或“12”，则可以使用“选择”选项类型；请参阅选项类型文档

回答by feinmann

Just to illustrate the choices-option of argparse.ArgumentParser's add_argument()-method:

只是为了说明 argparse.ArgumentParser 的 add_argument() 方法的选择选项：

#!/usr/bin/env python
# -*- coding: utf-8 -*-

import sys
from argparse import ArgumentParser
from datetime import date

parser = ArgumentParser()

parser.add_argument("-u", "--user", default="Max Power", help="Username")
parser.add_argument("-m", "--month", default="{:02d}".format(date.today().month),
                    choices=["01","02","03","04","05","06",
                             "07","08","09","10","11","12"],
                    help="Numeric value of the month")

try:
    args = parser.parse_args()
except:
    parser.error("Invalid Month.")
    sys.exit(0) 

print  "The month is {} and the User is {}".format(args.month, args.user)