10

argparse对于使用 argparse 的组之间的Python依赖关系,我有一个解析器的某个解析器组的参数部分 - 例如:

group_simulate.add_argument('-P',
                            help='simulate FC port down',
                            nargs=1,
                            metavar='fc_port_name',
                            dest='simulate')

如何使用选项将选项限制为下一个结构的参数列表:

1:m:"number between 1 and 10":p:"number between 1 and 4"

我尝试使用范围选项,但找不到创建可接受选项列表的方法

示例: 合法参数:

test.py -P 1:m:4:p:2

不合法的参数:

test.py -P 1:p:2
test.py -P abvds

非常感谢你们的帮助!

4

2 回答 2

21

argparse.ArgumentTypeError您可以定义一个自定义类型,如果字符串与您需要的格式不匹配,它将引发一个。

def SpecialString(v):
    fields = v.split(":")
    # Raise a value error for any part of the string
    # that doesn't match your specification. Make as many
    # checks as you need. I've only included a couple here
    # as examples.
    if len(fields) != 5:
        raise argparse.ArgumentTypeError("String must have 5 fields")
    elif not (1 <= int(fields[2]) <= 10):
        raise argparse.ArgumentTypeError("Field 3 must be between 1 and 10, inclusive")
    else:
        # If all the checks pass, just return the string as is
        return v

group_simulate.add_argument('-P',
                        type=SpecialString,
                        help='simulate FC port down',
                        nargs=1,
                        metavar='fc_port_name',
                        dest='simulate')

更新:这是一个完整的自定义类型来检查值。所有检查都在正则表达式中完成,尽管如果任何部分错误,它只会给出一个通用错误消息。

def SpecialString(v):
    import re  # Unless you've already imported re previously
    try:
        return re.match("^1:m:([1-9]|10):p:(1|2|3|4)$", v).group(0)
    except:
        raise argparse.ArgumentTypeError("String '%s' does not match required format"%(v,))
于 2013-02-05T16:15:30.483 回答
0

如果我正确理解了这个问题,那么您只是在寻找:

group_simulate.add_argument('-P',
                            help='simulate FC port down',
                            type=int, 
                            metavar='fc_port_name',
                            dest='simulate',
                            choices=range(1, 10)) # answer

来源:https ://docs.python.org/3/library/argparse.html#choices

于 2021-12-01T19:12:00.563 回答