blob: 6e38f26b6be063b7538bf8d3785b0ea4e0b7d992 [file] [log] [blame]
"""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.
The option values can contain format strings which refer to other values in
the same section, or values in a 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.
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,
delimiters=('=', ':'), comment_prefixes=('#', ';'),
empty_lines_in_values=True, allow_no_value=False):
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. Note that `__name__'
is always an intrinsic default; its value is the section's name.
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 a line.
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.
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 list of named configuration files, given by
name. A single filename is also allowed. Non-existing files
are ignored. Return list of successfully read files.
readfp(fp, filename=None)
Read and parse one configuration file, given as a file object.
The filename defaults to fp.name; it is only used in error
messages (if fp has no `name' attribute, the string `<???>' is used).
get(section, option, raw=False, vars=None)
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.
getint(section, options)
Like get(), but convert value to an integer.
getfloat(section, options)
Like get(), but convert value to a float.
getboolean(section, options)
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, raw=False, vars=None)
Return a list of tuples with (name, value) for each option
in the section.
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.
"""
try:
from collections import OrderedDict as _default_dict
except ImportError:
# fallback for setup.py which hasn't yet built _collections
_default_dict = dict
import re
import sys
__all__ = ["NoSectionError", "DuplicateSectionError", "NoOptionError",
"InterpolationError", "InterpolationDepthError",
"InterpolationSyntaxError", "ParsingError",
"MissingSectionHeaderError",
"ConfigParser", "SafeConfigParser", "RawConfigParser",
"DEFAULTSECT", "MAX_INTERPOLATION_DEPTH"]
DEFAULTSECT = "DEFAULT"
MAX_INTERPOLATION_DEPTH = 10
# exception classes
class Error(Exception):
"""Base class for ConfigParser exceptions."""
def _get_message(self):
"""Getter for 'message'; needed only to override deprecation in
BaseException.
"""
return self.__message
def _set_message(self, value):
"""Setter for 'message'; needed only to override deprecation in
BaseException.
"""
self.__message = value
# BaseException.message has been deprecated since Python 2.6. To prevent
# DeprecationWarning from popping up over this pre-existing attribute, use a
# new property that takes lookup precedence.
message = property(_get_message, _set_message)
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 multiply-created."""
def __init__(self, section):
Error.__init__(self, "Section %r already exists" % section)
self.section = section
self.args = (section, )
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:\n"
"\tsection: [%s]\n"
"\toption : %s\n"
"\tkey : %s\n"
"\trawval : %s\n"
% (section, option, 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 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 = ("Value interpolation too deeply recursive:\n"
"\tsection: [%s]\n"
"\toption : %s\n"
"\trawval : %s\n"
% (section, option, 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, filename):
Error.__init__(self, 'File contains parsing errors: %s' % filename)
self.filename = filename
self.errors = []
self.args = (filename, )
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: %s, line: %d\n%r' %
(filename, lineno, line))
self.filename = filename
self.lineno = lineno
self.line = line
self.args = (filename, lineno, line)
class RawConfigParser:
"""ConfigParser that does not do interpolation."""
# Regular expressions for parsing section headers and options
_SECT_TMPL = r"""
\[ # [
(?P<header>[^]]+) # very permissive!
\] # ]
"""
_OPT_TMPL = r"""
(?P<option>.*?) # very permissive!
\s*(?P<vi>{delim})\s* # any number of space/tab,
# followed by any of the
# allowed delimiters,
# followed by any space/tab
(?P<value>.*)$ # everything up to eol
"""
_OPT_NV_TMPL = r"""
(?P<option>.*?) # very permissive!
\s*(?: # any number of space/tab,
(?P<vi>{delim})\s* # optionally followed by
# any of the allowed
# delimiters, followed by any
# space/tab
(?P<value>.*))?$ # everything up to eol
"""
# Compiled regular expression for matching sections
SECTCRE = re.compile(_SECT_TMPL, re.VERBOSE)
# Compiled regular expression for matching options with typical separators
OPTCRE = re.compile(_OPT_TMPL.format(delim="=|:"), re.VERBOSE)
# Compiled regular expression for matching options with optional values
# delimited using typical separators
OPTCRE_NV = re.compile(_OPT_NV_TMPL.format(delim="=|:"), re.VERBOSE)
# Compiled regular expression for matching leading whitespace in a line
NONSPACECRE = re.compile(r"\S")
# Select backwards-compatible inline comment character behavior
# (; and # are comments at the start of a line, but ; only inline)
_COMPATIBLE = object()
def __init__(self, defaults=None, dict_type=_default_dict,
delimiters=('=', ':'), comment_prefixes=_COMPATIBLE,
empty_lines_in_values=True, allow_no_value=False):
self._dict = dict_type
self._sections = self._dict()
self._defaults = self._dict()
if defaults:
for key, value in defaults.items():
self._defaults[self.optionxform(key)] = value
self._delimiters = tuple(delimiters)
if delimiters == ('=', ':'):
self._optcre = self.OPTCRE_NV if allow_no_value else self.OPTCRE
else:
delim = "|".join(re.escape(d) for d in delimiters)
if allow_no_value:
self._optcre = re.compile(self._OPT_NV_TMPL.format(delim=delim),
re.VERBOSE)
else:
self._optcre = re.compile(self._OPT_TMPL.format(delim=delim),
re.VERBOSE)
if comment_prefixes is self._COMPATIBLE:
self._startonly_comment_prefixes = ('#',)
self._comment_prefixes = (';',)
else:
self._startonly_comment_prefixes = ()
self._comment_prefixes = tuple(comment_prefixes or ())
self._empty_lines_in_values = empty_lines_in_values
def defaults(self):
return self._defaults
def sections(self):
"""Return a list of section names, excluding [DEFAULT]"""
# self._sections will never have [DEFAULT] in it
return list(self._sections.keys())
def add_section(self, section):
"""Create a new section in the configuration.
Raise DuplicateSectionError if a section by the specified name
already exists. Raise ValueError if name is DEFAULT or any of it's
case-insensitive variants.
"""
if section.lower() == "default":
raise ValueError('Invalid section name: %s' % section)
if section in self._sections:
raise DuplicateSectionError(section)
self._sections[section] = self._dict()
def has_section(self, section):
"""Indicate whether the named section is present in the configuration.
The DEFAULT section is not acknowledged.
"""
return section in self._sections
def options(self, section):
"""Return a list of option names for the given section name."""
try:
opts = self._sections[section].copy()
except KeyError:
raise NoSectionError(section)
opts.update(self._defaults)
if '__name__' in opts:
del opts['__name__']
return list(opts.keys())
def read(self, filenames, encoding=None):
"""Read and parse a filename or a list of filenames.
Files that cannot be opened are silently ignored; this is
designed so that you can specify a list of potential
configuration file locations (e.g. current directory, user's
home directory, systemwide directory), and all existing
configuration files in the list will be read. A single
filename may also be given.
Return list of successfully read files.
"""
if isinstance(filenames, str):
filenames = [filenames]
read_ok = []
for filename in filenames:
try:
fp = open(filename, encoding=encoding)
except IOError:
continue
self._read(fp, filename)
fp.close()
read_ok.append(filename)
return read_ok
def readfp(self, fp, filename=None):
"""Like read() but the argument must be a file-like object.
The `fp' argument must have a `readline' method. Optional
second argument is the `filename', which if not given, is
taken from fp.name. If fp has no `name' attribute, `<???>' is
used.
"""
if filename is None:
try:
filename = fp.name
except AttributeError:
filename = '<???>'
self._read(fp, filename)
def get(self, section, option):
opt = self.optionxform(option)
if section not in self._sections:
if section != DEFAULTSECT:
raise NoSectionError(section)
if opt in self._defaults:
return self._defaults[opt]
else:
raise NoOptionError(option, section)
elif opt in self._sections[section]:
return self._sections[section][opt]
elif opt in self._defaults:
return self._defaults[opt]
else:
raise NoOptionError(option, section)
def items(self, section):
try:
d2 = self._sections[section]
except KeyError:
if section != DEFAULTSECT:
raise NoSectionError(section)
d2 = self._dict()
d = self._defaults.copy()
d.update(d2)
if "__name__" in d:
del d["__name__"]
return d.items()
def _get(self, section, conv, option):
return conv(self.get(section, option))
def getint(self, section, option):
return self._get(section, int, option)
def getfloat(self, section, option):
return self._get(section, float, option)
_boolean_states = {'1': True, 'yes': True, 'true': True, 'on': True,
'0': False, 'no': False, 'false': False, 'off': False}
def getboolean(self, section, option):
v = self.get(section, option)
if v.lower() not in self._boolean_states:
raise ValueError('Not a boolean: %s' % v)
return self._boolean_states[v.lower()]
def optionxform(self, optionstr):
return optionstr.lower()
def has_option(self, section, option):
"""Check for the existence of a given option in a given section."""
if not section or section == DEFAULTSECT:
option = self.optionxform(option)
return option in self._defaults
elif section not in self._sections:
return False
else:
option = self.optionxform(option)
return (option in self._sections[section]
or option in self._defaults)
def set(self, section, option, value=None):
"""Set an option."""
if not section or section == DEFAULTSECT:
sectdict = self._defaults
else:
try:
sectdict = self._sections[section]
except KeyError:
raise NoSectionError(section)
sectdict[self.optionxform(option)] = value
def write(self, fp, space_around_delimiters=True):
"""Write an .ini-format representation of the configuration state.
If `space_around_delimiters' is True (the default), delimiters
between keys and values are surrounded by spaces.
"""
if space_around_delimiters:
d = " {} ".format(self._delimiters[0])
else:
d = self._delimiters[0]
if self._defaults:
self._write_section(fp, DEFAULTSECT, self._defaults.items(), d)
for section in self._sections:
self._write_section(fp, section,
self._sections[section].items(), d)
def _write_section(self, fp, section_name, section_items, delimiter):
"""Write a single section to the specified `fp'."""
fp.write("[{}]\n".format(section_name))
for key, value in section_items:
if key == "__name__":
continue
if value is not None:
value = delimiter + str(value).replace('\n', '\n\t')
else:
value = ""
fp.write("{}{}\n".format(key, value))
fp.write("\n")
def remove_option(self, section, option):
"""Remove an option."""
if not section or section == DEFAULTSECT:
sectdict = self._defaults
else:
try:
sectdict = self._sections[section]
except KeyError:
raise NoSectionError(section)
option = self.optionxform(option)
existed = option in sectdict
if existed:
del sectdict[option]
return existed
def remove_section(self, section):
"""Remove a file section."""
existed = section in self._sections
if existed:
del self._sections[section]
return existed
def _read(self, fp, fpname):
"""Parse a sectioned configuration file.
Each section in a configuration file contains a header, indicated by a
name in square brackets (`[]'), plus key/value options, indicated by
`name' and `value' delimited with a specific substring (`=' or `:' by
default).
Values can span multiple lines, as long as they are indented deeper than
the first line of the value. Depending on the parser's mode, blank lines
may be treated as parts of multiline values or ignored.
Configuration files may include comments, prefixed by specific
characters (`#' and `;' by default). Comments may appear on their own in
an otherwise empty line or may be entered in lines holding values or
section names.
"""
cursect = None # None, or a dictionary
optname = None
lineno = 0
indent_level = 0
e = None # None, or an exception
for lineno, line in enumerate(fp, start=1):
# strip full line comments
comment_start = None
for prefix in self._startonly_comment_prefixes:
if line.strip().startswith(prefix):
comment_start = 0
break
# strip inline comments
for prefix in self._comment_prefixes:
index = line.find(prefix)
if index == 0 or (index > 0 and line[index-1].isspace()):
comment_start = index
break
value = line[:comment_start].strip()
if not value:
if self._empty_lines_in_values:
# add empty line to the value, but only if there was no
# comment on the line
if (comment_start is None and
cursect is not None and
optname and
cursect[optname] is not None):
cursect[optname].append('') # newlines added at join
else:
# empty line marks end of value
indent_level = sys.maxsize
continue
# continuation line?
first_nonspace = self.NONSPACECRE.search(line)
cur_indent_level = first_nonspace.start() if first_nonspace else 0
if (cursect is not None and optname and
cur_indent_level > indent_level):
cursect[optname].append(value)
# a section header or option header?
else:
indent_level = cur_indent_level
# is it a section header?
mo = self.SECTCRE.match(value)
if mo:
sectname = mo.group('header')
if sectname in self._sections:
cursect = self._sections[sectname]
elif sectname == DEFAULTSECT:
cursect = self._defaults
else:
cursect = self._dict()
cursect['__name__'] = sectname
self._sections[sectname] = cursect
# So sections can't start with a continuation line
optname = None
# no section header in the file?
elif cursect is None:
raise MissingSectionHeaderError(fpname, lineno, line)
# an option line?
else:
mo = self._optcre.match(value)
if mo:
optname, vi, optval = mo.group('option', 'vi', 'value')
if not optname:
e = self._handle_error(e, fpname, lineno, line)
optname = self.optionxform(optname.rstrip())
# This check is fine because the OPTCRE cannot
# match if it would set optval to None
if optval is not None:
optval = optval.strip()
# allow empty values
if optval == '""':
optval = ''
cursect[optname] = [optval]
else:
# valueless option handling
cursect[optname] = optval
else:
# a non-fatal parsing error occurred. set up the
# exception but keep going. the exception will be
# raised at the end of the file and will contain a
# list of all bogus lines
e = self._handle_error(e, fpname, lineno, line)
# if any parsing errors occurred, raise an exception
if e:
raise e
self._join_multiline_values()
def _join_multiline_values(self):
all_sections = [self._defaults]
all_sections.extend(self._sections.values())
for options in all_sections:
for name, val in options.items():
if isinstance(val, list):
options[name] = '\n'.join(val).rstrip()
def _handle_error(self, exc, fpname, lineno, line):
if not exc:
exc = ParsingError(fpname)
exc.append(lineno, repr(line))
return exc
class ConfigParser(RawConfigParser):
"""ConfigParser implementing interpolation."""
def get(self, section, option, raw=False, vars=None):
"""Get an option value for a given section.
If `vars' is provided, it must be a dictionary. The option is looked up
in `vars' (if provided), `section', and in `defaults' in that order.
All % interpolations are expanded in the return values, unless the
optional argument `raw' is true. Values for interpolation keys are
looked up in the same manner as the option.
The section DEFAULT is special.
"""
d = self._defaults.copy()
try:
d.update(self._sections[section])
except KeyError:
if section != DEFAULTSECT:
raise NoSectionError(section)
# Update with the entry specific variables
if vars:
for key, value in vars.items():
d[self.optionxform(key)] = value
option = self.optionxform(option)
try:
value = d[option]
except KeyError:
raise NoOptionError(option, section)
if raw or value is None:
return value
else:
return self._interpolate(section, option, value, d)
def items(self, section, raw=False, vars=None):
"""Return a list of tuples with (name, value) for each option
in the section.
All % interpolations are expanded in the return values, based on the
defaults passed into the constructor, unless the optional argument
`raw' is true. Additional substitutions may be provided using the
`vars' argument, which must be a dictionary whose contents overrides
any pre-existing defaults.
The section DEFAULT is special.
"""
d = self._defaults.copy()
try:
d.update(self._sections[section])
except KeyError:
if section != DEFAULTSECT:
raise NoSectionError(section)
# Update with the entry specific variables
if vars:
for key, value in vars.items():
d[self.optionxform(key)] = value
options = list(d.keys())
if "__name__" in options:
options.remove("__name__")
if raw:
return [(option, d[option])
for option in options]
else:
return [(option, self._interpolate(section, option, d[option], d))
for option in options]
def _interpolate(self, section, option, rawval, vars):
# do the string interpolation
value = rawval
depth = MAX_INTERPOLATION_DEPTH
while depth: # Loop through this until it's done
depth -= 1
if value and "%(" in value:
value = self._KEYCRE.sub(self._interpolation_replace, value)
try:
value = value % vars
except KeyError as e:
raise InterpolationMissingOptionError(
option, section, rawval, e.args[0])
else:
break
if value and "%(" in value:
raise InterpolationDepthError(option, section, rawval)
return value
_KEYCRE = re.compile(r"%\(([^)]*)\)s|.")
def _interpolation_replace(self, match):
s = match.group(1)
if s is None:
return match.group()
else:
return "%%(%s)s" % self.optionxform(s)
class SafeConfigParser(ConfigParser):
"""ConfigParser implementing sane interpolation."""
def _interpolate(self, section, option, rawval, vars):
# do the string interpolation
L = []
self._interpolate_some(option, L, rawval, section, vars, 1)
return ''.join(L)
_interpvar_re = re.compile(r"%\(([^)]+)\)s")
def _interpolate_some(self, option, accum, rest, section, map, depth):
if depth > MAX_INTERPOLATION_DEPTH:
raise InterpolationDepthError(option, section, rest)
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._interpvar_re.match(rest)
if m is None:
raise InterpolationSyntaxError(option, section,
"bad interpolation variable reference %r" % rest)
var = self.optionxform(m.group(1))
rest = rest[m.end():]
try:
v = map[var]
except KeyError:
raise InterpolationMissingOptionError(
option, section, rest, var)
if "%" in v:
self._interpolate_some(option, accum, v,
section, map, depth + 1)
else:
accum.append(v)
else:
raise InterpolationSyntaxError(
option, section,
"'%%' must be followed by '%%' or '(', found: %r" % (rest,))
def set(self, section, option, value=None):
"""Set an option. Extend ConfigParser.set: check for string values."""
# The only legal non-string value if we allow valueless
# options is None, so we need to check if the value is a
# string if:
# - we do not allow valueless options, or
# - we allow valueless options but the value is not None
if self._optcre is self.OPTCRE or value:
if not isinstance(value, str):
raise TypeError("option values must be strings")
# check for bad percent signs:
# first, replace all "good" interpolations
tmp_value = value.replace('%%', '')
tmp_value = self._interpvar_re.sub('', tmp_value)
# then, check if there's a lone percent sign left
percent_index = tmp_value.find('%')
if percent_index != -1:
raise ValueError("invalid interpolation syntax in %r at "
"position %d" % (value, percent_index))
ConfigParser.set(self, section, option, value)