使用Python的ConfigParser读取没有部分名称的文件

Question

我正在使用ConfigParser来读取脚本的运行时配置.

我希望能够灵活地不提供部分名称(有足够简单的脚本;它们不需要'部分').ConfigParser将抛出ConfigParser异常,并且不接受该文件.

如何使ConfigParser只检索ConfigParser没有部分名称的配置文件的元组？例如:

key1=val1
key2:val2

我宁愿不写入配置文件.

Answer 1

Alex Martelli 提供了一个用于ConfigParser解析.properties文件的解决方案(显然是无部分的配置文件).

他的解决方案是一个类似文件的包装器,它将自动插入一个虚拟部分标题以满足ConfigParser要求.

Answer 2

受到jterrace的这个答案的启发,我提出了这个解决方案:

1. 将整个文件读入字符串
2. 带有默认部分名称的前缀
3. 使用StringIO来模仿类文件对象

ini_str = '[root]\n' + open(ini_path, 'r').read()
ini_fp = StringIO.StringIO(ini_str)
config = ConfigParser.RawConfigParser()
config.readfp(ini_fp)

编辑未来的googlers:截至Python 3.4+ readfp已被弃用,StringIO不再需要了.相反,我们可以read_string直接使用:

with open('config_file') as f:
    file_content = '[dummy_section]\n' + f.read()

config_parser = ConfigParser.RawConfigParser()
config_parser.read_string(file_content)

Answer 3

您可以使用一行额外的代码执行此操作.(如果计算read_string()语句,则为两行.)

在python 3中,用于itertools.chain()模拟节标题read_file().

from configparser import ConfigParser

parser = ConfigParser()
with open("foo.conf") as stream:
    parser.read_string("[top]\n" + stream.read())  # This line does the trick.

在python 2中,在从配置文件中读取的数据前面加上一个节标题行,将结果包装在一个StringIO对象中,并将其传递给readfp().

from configparser import ConfigParser
from itertools import chain

parser = ConfigParser()
with open("foo.conf") as lines:
    lines = chain(("[top]",), lines)  # This line does the trick.
    parser.read_file(lines)

无论使用哪种方法,您的配置设置都可用parser.items('top').

您也可以io在python 3中使用它,从readfp()包中的新主页导入它,但请注意,read_string()在python 3中已弃用,因此应避免使用.

如果您不介意额外的依赖项,可以考虑使用TOML解析器而不是ConfigParser.

Answer 4

您可以使用ConfigObj库来执行此操作:http://www.voidspace.org.uk/python/configobj.html

更新:在此处查找最新代码.

如果您在Debian/Ubuntu下,可以使用包管理器安装此模块:

apt-get install python-configobj

使用示例:

from configobj import ConfigObj

config = ConfigObj('myConfigFile.ini')
config.get('key1') # You will get val1
config.get('key2') # You will get val2

Answer 5

在我看来,最简单的方法是使用python的CSV解析器.这是一个读/写函数,演示了这种方法以及测试驱动程序.如果不允许多行值,这应该工作.:)

import csv
import operator

def read_properties(filename):
    """ Reads a given properties file with each line of the format key=value.  Returns a dictionary containing the pairs.

    Keyword arguments:
        filename -- the name of the file to be read
    """
    result={ }
    with open(filename, "rb") as csvfile:
        reader = csv.reader(csvfile, delimiter='=', escapechar='\\', quoting=csv.QUOTE_NONE)
        for row in reader:
            if len(row) != 2:
                raise csv.Error("Too many fields on row with contents: "+str(row))
            result[row[0]] = row[1] 
    return result

def write_properties(filename,dictionary):
    """ Writes the provided dictionary in key-sorted order to a properties file with each line of the format key=value

    Keyword arguments:
        filename -- the name of the file to be written
        dictionary -- a dictionary containing the key/value pairs.
    """
    with open(filename, "wb") as csvfile:
        writer = csv.writer(csvfile, delimiter='=', escapechar='\\', quoting=csv.QUOTE_NONE)
        for key, value in sorted(dictionary.items(), key=operator.itemgetter(0)):
                writer.writerow([ key, value])

def main():
    data={
        "Hello": "5+5=10",
        "World": "Snausage",
        "Awesome": "Possum"
    }

    filename="test.properties"
    write_properties(filename,data)
    newdata=read_properties(filename)

    print "Read in: "
    print newdata
    print

    contents=""
    with open(filename, 'rb') as propfile:
        contents=propfile.read()
    print "File contents:"
    print contents

    print ["Failure!", "Success!"][data == newdata]
    return

if __name__ == '__main__': 
     main() 

Answer 6

自己遇到这个问题后,我为ConfigParser(Python 2中的版本)编写了一个完整的包装器,它可以透明地读取和写入没有部分的文件,基于Alex Martelli的方法与已接受的答案相关联.它应该是对ConfigParser的任何使用的替代品.发布它以防有需要的人找到这个页面.

import ConfigParser
import StringIO

class SectionlessConfigParser(ConfigParser.RawConfigParser):
    """
    Extends ConfigParser to allow files without sections.

    This is done by wrapping read files and prepending them with a placeholder
    section, which defaults to '__config__'
    """

    def __init__(self, *args, **kwargs):
        default_section = kwargs.pop('default_section', None)
        ConfigParser.RawConfigParser.__init__(self, *args, **kwargs)

        self._default_section = None
        self.set_default_section(default_section or '__config__')

    def get_default_section(self):
        return self._default_section

    def set_default_section(self, section):
        self.add_section(section)

        # move all values from the previous default section to the new one
        try:
            default_section_items = self.items(self._default_section)
            self.remove_section(self._default_section)
        except ConfigParser.NoSectionError:
            pass
        else:
            for (key, value) in default_section_items:
                self.set(section, key, value)

        self._default_section = section

    def read(self, filenames):
        if isinstance(filenames, basestring):
            filenames = [filenames]

        read_ok = []
        for filename in filenames:
            try:
                with open(filename) as fp:
                    self.readfp(fp)
            except IOError:
                continue
            else:
                read_ok.append(filename)

        return read_ok

    def readfp(self, fp, *args, **kwargs):
        stream = StringIO()

        try:
            stream.name = fp.name
        except AttributeError:
            pass

        stream.write('[' + self._default_section + ']\n')
        stream.write(fp.read())
        stream.seek(0, 0)

        return ConfigParser.RawConfigParser.readfp(self, stream, *args,
                                                   **kwargs)

    def write(self, fp):
        # Write the items from the default section manually and then remove them
        # from the data. They'll be re-added later.
        try:
            default_section_items = self.items(self._default_section)
            self.remove_section(self._default_section)

            for (key, value) in default_section_items:
                fp.write("{0} = {1}\n".format(key, value))

            fp.write("\n")
        except ConfigParser.NoSectionError:
            pass

        ConfigParser.RawConfigParser.write(self, fp)

        self.add_section(self._default_section)
        for (key, value) in default_section_items:
            self.set(self._default_section, key, value)

Answer 7

Blueicefield的回答提到了configobj,但原始的lib只支持Python 2.它现在有一个Python 3+兼容端口:

https://github.com/DiffSK/configobj

API没有改变,请看它的文档.