5.17 ConfigParser -- Configuration file parser

Python PEP

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5.17 `ConfigParser` -- Configuration file parser

This module defines the class ConfigParser. The ConfigParser class implements a basic configuration file parser language which provides a structure similar to what you would find on Microsoft Windows INI files. You can use this to write Python programs which can be customized by end users easily.

Warning: This library does not interpret or write the value-type prefixes used in the Windows Registry extended version of INI syntax.

The configuration file consists of sections, led by a "[section]" header and followed by "name: value" entries, with continuations in the style of RFC 822; "name=value" is also accepted. Note that leading whitespace is removed from values. The optional values can contain format strings which refer to other values in the same section, or values in a special DEFAULT section. Additional defaults can be provided on initialization and retrieval. Lines beginning with "#" or ";" are ignored and may be used to provide comments.

For example:

[My Section]
foodir: %(dir)s/whatever
dir=frob

would resolve the "%(dir)s" to the value of "dir" ("frob" in this case). All reference expansions are done on demand.

Default values can be specified by passing them into the ConfigParser constructor as a dictionary. Additional defaults may be passed into the get() method which will override all others.

class RawConfigParser( [defaults]): The basic configuration object. When defaults is given, it is initialized into the dictionary of intrinsic defaults. This class does not support the magical interpolation behavior. New in version 2.3.

class ConfigParser( [defaults]): Derived class of RawConfigParser that implements the magical interpolation feature and adds optional arguments to the get() and items() methods. The values in defaults must be appropriate for the "%()s" string interpolation. Note that __name__ is an intrinsic default; its value is the section name, and will override any value provided in defaults.
All option names used in interpolation will be passed through the optionxform() method just like any other option name reference. For example, using the default implementation of optionxform() (which converts option names to lower case), the values "foo %(bar)s" and "foo %(BAR)s" are equivalent.

class SafeConfigParser( [defaults]): Derived class of ConfigParser that implements a more-sane variant of the magical interpolation feature. This implementation is more predictable as well. New applications should prefer this version if they don't need to be compatible with older versions of Python. New in version 2.3.

exception NoSectionError: Exception raised when a specified section is not found.

exception DuplicateSectionError: Exception raised if add_section() is called with the name of a section that is already present.

exception NoOptionError: Exception raised when a specified option is not found in the specified section.

exception InterpolationError: Base class for exceptions raised when problems occur performing string interpolation.

exception InterpolationDepthError: Exception raised when string interpolation cannot be completed because the number of iterations exceeds MAX_INTERPOLATION_DEPTH. Subclass of InterpolationError.

exception InterpolationMissingOptionError: Exception raised when an option referenced from a value does not exist. Subclass of InterpolationError. New in version 2.3.

exception InterpolationSyntaxError: Exception raised when the source text into which substitutions are made does not conform to the required syntax. Subclass of InterpolationError. New in version 2.3.

exception MissingSectionHeaderError: Exception raised when attempting to parse a file which has no section headers.

exception ParsingError: Exception raised when errors occur attempting to parse a file.

MAX_INTERPOLATION_DEPTH: The maximum depth for recursive interpolation for get() when the raw parameter is false. This is relevant only for the ConfigParser class.