"""Configuration file parser.
A configuration file consists of sections, lead by a "[section]" header,
and followed by "name: value" entries, with continuations and such in
the style of RFC 822.
Intrinsic defaults can be specified by passing them into the
ConfigParser constructor as a dictionary.
class:
ConfigParser -- responsible for parsing a list of
configuration files, and managing the parsed database.
methods:
__init__(defaults=None, dict_type=_default_dict, allow_no_value=False,
delimiters=('=', ':'), comment_prefixes=('#', ';'),
inline_comment_prefixes=None, strict=True,
empty_lines_in_values=True, default_section='DEFAULT',
interpolation=, converters=):
Create the parser. When `defaults` is given, it is initialized into the
dictionary or intrinsic defaults. The keys must be strings, the values
must be appropriate for %()s string interpolation.
When `dict_type` is given, it will be used to create the dictionary
objects for the list of sections, for the options within a section, and
for the default values.
When `delimiters` is given, it will be used as the set of substrings
that divide keys from values.
When `comment_prefixes` is given, it will be used as the set of
substrings that prefix comments in empty lines. Comments can be
indented.
When `inline_comment_prefixes` is given, it will be used as the set of
substrings that prefix comments in non-empty lines.
When `strict` is True, the parser won't allow for any section or option
duplicates while reading from a single source (file, string or
dictionary). Default is True.
When `empty_lines_in_values` is False (default: True), each empty line
marks the end of an option. Otherwise, internal empty lines of
a multiline option are kept as part of the value.
When `allow_no_value` is True (default: False), options without
values are accepted; the value presented for these is None.
When `default_section` is given, the name of the special section is
named accordingly. By default it is called ``"DEFAULT"`` but this can
be customized to point to any other valid section name. Its current
value can be retrieved using the ``parser_instance.default_section``
attribute and may be modified at runtime.
When `interpolation` is given, it should be an Interpolation subclass
instance. It will be used as the handler for option value
pre-processing when using getters. RawConfigParser objects don't do
any sort of interpolation, whereas ConfigParser uses an instance of
BasicInterpolation. The library also provides a ``zc.buildout``
inspired ExtendedInterpolation implementation.
When `converters` is given, it should be a dictionary where each key
represents the name of a type converter and each value is a callable
implementing the conversion from string to the desired datatype. Every
converter gets its corresponding get*() method on the parser object and
section proxies.
sections()
Return all the configuration section names, sans DEFAULT.
has_section(section)
Return whether the given section exists.
has_option(section, option)
Return whether the given option exists in the given section.
options(section)
Return list of configuration options for the named section.
read(filenames, encoding=None)
Read and parse the iterable of named configuration files, given by
name. A single filename is also allowed. Non-existing files
are ignored. Return list of successfully read files.
read_file(f, filename=None)
Read and parse one configuration file, given as a file object.
The filename defaults to f.name; it is only used in error
messages (if f has no `name` attribute, the string `` is used).
read_string(string)
Read configuration from a given string.
read_dict(dictionary)
Read configuration from a dictionary. Keys are section names,
values are dictionaries with keys and values that should be present
in the section. If the used dictionary type preserves order, sections
and their keys will be added in order. Values are automatically
converted to strings.
get(section, option, raw=False, vars=None, fallback=_UNSET)
Return a string value for the named option. All % interpolations are
expanded in the return values, based on the defaults passed into the
constructor and the DEFAULT section. Additional substitutions may be
provided using the `vars` argument, which must be a dictionary whose
contents override any pre-existing defaults. If `option` is a key in
`vars`, the value from `vars` is used.
getint(section, options, raw=False, vars=None, fallback=_UNSET)
Like get(), but convert value to an integer.
getfloat(section, options, raw=False, vars=None, fallback=_UNSET)
Like get(), but convert value to a float.
getboolean(section, options, raw=False, vars=None, fallback=_UNSET)
Like get(), but convert value to a boolean (currently case
insensitively defined as 0, false, no, off for False, and 1, true,
yes, on for True). Returns False or True.
items(section=_UNSET, raw=False, vars=None)
If section is given, return a list of tuples with (name, value) for
each option in the section. Otherwise, return a list of tuples with
(section_name, section_proxy) for each section, including DEFAULTSECT.
remove_section(section)
Remove the given file section and all its options.
remove_option(section, option)
Remove the given option from the given section.
set(section, option, value)
Set the given option.
write(fp, space_around_delimiters=True)
Write the configuration state in .ini format. If
`space_around_delimiters` is True (the default), delimiters
between keys and values are surrounded by spaces.
"""
from collections.abc import MutableMapping
from collections import ChainMap as _ChainMap
import functools
import io
import itertools
import os
import re
import sys
import warnings
__all__ = ("NoSectionError", "DuplicateOptionError", "DuplicateSectionError",
"NoOptionError", "InterpolationError", "InterpolationDepthError",
"InterpolationMissingOptionError", "InterpolationSyntaxError",
"ParsingError", "MissingSectionHeaderError",
"ConfigParser", "RawConfigParser",
"Interpolation", "BasicInterpolation", "ExtendedInterpolation",
"LegacyInterpolation", "SectionProxy", "ConverterMapping",
"DEFAULTSECT", "MAX_INTERPOLATION_DEPTH")
_default_dict = dict
DEFAULTSECT = "DEFAULT"
MAX_INTERPOLATION_DEPTH = 10
# exception classes
class Error(Exception):
"""Base class for ConfigParser exceptions."""
def __init__(self, msg=''):
self.message = msg
Exception.__init__(self, msg)
def __repr__(self):
return self.message
__str__ = __repr__
class NoSectionError(Error):
"""Raised when no section matches a requested option."""
def __init__(self, section):
Error.__init__(self, 'No section: %r' % (section,))
self.section = section
self.args = (section, )
class DuplicateSectionError(Error):
"""Raised when a section is repeated in an input source.
Possible repetitions that raise this exception are: multiple creation
using the API or in strict parsers when a section is found more than once
in a single input file, string or dictionary.
"""
def __init__(self, section, source=None, lineno=None):
msg = [repr(section), " already exists"]
if source is not None:
message = ["While reading from ", repr(source)]
if lineno is not None:
message.append(" [line {0:2d}]".format(lineno))
message.append(": section ")
message.extend(msg)
msg = message
else:
msg.insert(0, "Section ")
Error.__init__(self, "".join(msg))
self.section = section
self.source = source
self.lineno = lineno
self.args = (section, source, lineno)
class DuplicateOptionError(Error):
"""Raised by strict parsers when an option is repeated in an input source.
Current implementation raises this exception only when an option is found
more than once in a single file, string or dictionary.
"""
def __init__(self, section, option, source=None, lineno=None):
msg = [repr(option), " in section ", repr(section),
" already exists"]
if source is not None:
message = ["While reading from ", repr(source)]
if lineno is not None:
message.append(" [line {0:2d}]".format(lineno))
message.append(": option ")
message.extend(msg)
msg = message
else:
msg.insert(0, "Option ")
Error.__init__(self, "".join(msg))
self.section = section
self.option = option
self.source = source
self.lineno = lineno
self.args = (section, option, source, lineno)
class NoOptionError(Error):
"""A requested option was not found."""
def __init__(self, option, section):
Error.__init__(self, "No option %r in section: %r" %
(option, section))
self.option = option
self.section = section
self.args = (option, section)
class InterpolationError(Error):
"""Base class for interpolation-related exceptions."""
def __init__(self, option, section, msg):
Error.__init__(self, msg)
self.option = option
self.section = section
self.args = (option, section, msg)
class InterpolationMissingOptionError(InterpolationError):
"""A string substitution required a setting which was not available."""
def __init__(self, option, section, rawval, reference):
msg = ("Bad value substitution: option {!r} in section {!r} contains "
"an interpolation key {!r} which is not a valid option name. "
"Raw value: {!r}".format(option, section, reference, rawval))
InterpolationError.__init__(self, option, section, msg)
self.reference = reference
self.args = (option, section, rawval, reference)
class InterpolationSyntaxError(InterpolationError):
"""Raised when the source text contains invalid syntax.
Current implementation raises this exception when the source text into
which substitutions are made does not conform to the required syntax.
"""
class InterpolationDepthError(InterpolationError):
"""Raised when substitutions are nested too deeply."""
def __init__(self, option, section, rawval):
msg = ("Recursion limit exceeded in value substitution: option {!r} "
"in section {!r} contains an interpolation key which "
"cannot be substituted in {} steps. Raw value: {!r}"
"".format(option, section, MAX_INTERPOLATION_DEPTH,
rawval))
InterpolationError.__init__(self, option, section, msg)
self.args = (option, section, rawval)
class ParsingError(Error):
"""Raised when a configuration file does not follow legal syntax."""
def __init__(self, source):
super().__init__(f'Source contains parsing errors: {source!r}')
self.source = source
self.errors = []
self.args = (source, )
def append(self, lineno, line):
self.errors.append((lineno, line))
self.message += '\n\t[line %2d]: %s' % (lineno, line)
class MissingSectionHeaderError(ParsingError):
"""Raised when a key-value pair is found before any section header."""
def __init__(self, filename, lineno, line):
Error.__init__(
self,
'File contains no section headers.\nfile: %r, line: %d\n%r' %
(filename, lineno, line))
self.source = filename
self.lineno = lineno
self.line = line
self.args = (filename, lineno, line)
# Used in parser getters to indicate the default behaviour when a specific
# option is not found it to raise an exception. Created to enable `None` as
# a valid fallback value.
_UNSET = object()
class Interpolation:
"""Dummy interpolation that passes the value through with no changes."""
def before_get(self, parser, section, option, value, defaults):
return value
def before_set(self, parser, section, option, value):
return value
def before_read(self, parser, section, option, value):
return value
def before_write(self, parser, section, option, value):
return value
class BasicInterpolation(Interpolation):
"""Interpolation as implemented in the classic ConfigParser.
The option values can contain format strings which refer to other values in
the same section, or values in the special default section.
For example:
something: %(dir)s/whatever
would resolve the "%(dir)s" to the value of dir. All reference
expansions are done late, on demand. If a user needs to use a bare % in
a configuration file, she can escape it by writing %%. Other % usage
is considered a user error and raises `InterpolationSyntaxError`."""
_KEYCRE = re.compile(r"%\(([^)]+)\)s")
def before_get(self, parser, section, option, value, defaults):
L = []
self._interpolate_some(parser, option, L, value, section, defaults, 1)
return ''.join(L)
def before_set(self, parser, section, option, value):
tmp_value = value.replace('%%', '') # escaped percent signs
tmp_value = self._KEYCRE.sub('', tmp_value) # valid syntax
if '%' in tmp_value:
raise ValueError("invalid interpolation syntax in %r at "
"position %d" % (value, tmp_value.find('%')))
return value
def _interpolate_some(self, parser, option, accum, rest, section, map,
depth):
rawval = parser.get(section, option, raw=True, fallback=rest)
if depth > MAX_INTERPOLATION_DEPTH:
raise InterpolationDepthError(option, section, rawval)
while rest:
p = rest.find("%")
if p < 0:
accum.append(rest)
return
if p > 0:
accum.append(rest[:p])
rest = rest[p:]
# p is no longer used
c = rest[1:2]
if c == "%":
accum.append("%")
rest = rest[2:]
elif c == "(":
m = self._KEYCRE.match(rest)
if m is None:
raise InterpolationSyntaxError(option, section,
"bad interpolation variable reference %r" % rest)
var = parser.optionxform(m.group(1))
rest = rest[m.end():]
try:
v = map[var]
except KeyError:
raise InterpolationMissingOptionError(
option, section, rawval, var) from None
if "%" in v:
self._interpolate_some(parser, option, accum, v,
section, map, depth + 1)
else:
accum.append(v)
else:
raise InterpolationSyntaxError(
option, section,
"'%%' must be followed by '%%' or '(', "
"found: %r" % (rest,))
class ExtendedInterpolation(Interpolation):
"""Advanced variant of interpolation, supports the syntax used by
`zc.buildout`. Enables interpolation between sections."""
_KEYCRE = re.compile(r"\$\{([^}]+)\}")
def before_get(self, parser, section, option, value, defaults):
L = []
self._interpolate_some(parser, option, L, value, section, defaults, 1)
return ''.join(L)
def before_set(self, parser, section, option, value):
tmp_value = value.replace('$$', '') # escaped dollar signs
tmp_value = self._KEYCRE.sub('', tmp_value) # valid syntax
if '$' in tmp_value:
raise ValueError("invalid interpolation syntax in %r at "
"position %d" % (value, tmp_value.find('$')))
return value
def _interpolate_some(self, parser, option, accum, rest, section, map,
depth):
rawval = parser.get(section, option, raw=True, fallback=rest)
if depth > MAX_INTERPOLATION_DEPTH:
raise InterpolationDepthError(option, section, rawval)
while rest:
p = rest.find("$")
if p < 0:
accum.append(rest)
return
if p > 0:
accum.append(rest[:p])
rest = rest[p:]
# p is no longer used
c = rest[1:2]
if c == "$":
accum.append("$")
rest = rest[2:]
elif c == "{":
m = self._KEYCRE.match(rest)
if m is None:
raise InterpolationSyntaxError(option, section,
"bad interpolation variable reference %r" % rest)
path = m.group(1).split(':')
rest = rest[m.end():]
sect = section
opt = option
try:
if len(path) == 1:
opt = parser.optionxform(path[0])
v = map[opt]
elif len(path) == 2:
sect = path[0]
opt = parser.optionxform(path[1])
v = parser.get(sect, opt, raw=True)
else:
raise InterpolationSyntaxError(
option, section,
"More than one ':' found: %r" % (rest,))
except (KeyError, NoSectionError, NoOptionError):
raise InterpolationMissingOptionError(
option, section, rawval, ":".join(path)) from None
if "$" in v:
self._interpolate_some(parser, opt, accum, v, sect,
dict(parser.items(sect, raw=True)),
depth + 1)
else:
accum.append(v)
else:
raise InterpolationSyntaxError(
option, section,
"'$' must be followed by '$' or '{', "
"found: %r" % (rest,))
class LegacyInterpolation(Interpolation):
"""Deprecated interpolation used in old versions of ConfigParser.
Use BasicInterpolation or ExtendedInterpolation instead."""
_KEYCRE = re.compile(r"%\(([^)]*)\)s|.")
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
warnings.warn(
"LegacyInterpolation has been deprecated since Python 3.2 "
"and will be removed from the configparser module in Python 3.13. "
"Use BasicInterpolation or ExtendedInterpolation instead.",
DeprecationWarning, stacklevel=2
)
def before_get(self, parser, section, option, value, vars):
rawval = value
depth = MAX_INTERPOLATION_DEPTH
while depth: # Loop through this until it's done
depth -= 1
if value and "%(" in value:
replace = functools.partial(self._interpolation_replace,
parser=parser)
value = self._KEYCRE.sub(replace, value)
try:
value = value % vars
except KeyError as e:
raise InterpolationMissingOptionError(
option, section, rawval, e.args[0]) from None
else:
break
if value and "%(" in value:
raise InterpolationDepthError(option, section, rawval)
return value
def before_set(self, parser, section, option, value):
return value
@staticmethod
def _interpolation_replace(match, parser):
s = match.group(1)
if s is None:
return match.group()
else:
return "%%(%s)s" % parser.optionxform(s)
class RawConfigParser(MutableMapping):
"""ConfigParser that does not do interpolation."""
# Regular expressions for parsing section headers and options
_SECT_TMPL = r"""
\[ # [
(?P.+) # very permissive!
\] # ]
"""
_OPT_TMPL = r"""
(?P