"""Configuration file parser.
A setup 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)
create the parser and specify a dictionary of 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.
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)
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)
write the configuration state in .ini format
"""
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
__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:
def __init__(self, defaults=None, dict_type=_default_dict,
allow_no_value=False):
self._dict = dict_type
self._sections = self._dict()
self._defaults = self._dict()
if allow_no_value:
self._optcre = self.OPTCRE_NV
else:
self._optcre = self.OPTCRE
if defaults:
for key, value in defaults.items():
self._defaults[self.optionxform(key)] = value
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 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 opts.keys()
def read(self, filenames):
"""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, basestring):
filenames = [filenames]
read_ok = []
for filename in filenames:
try:
fp = open(filename)
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):
"""Write an .ini-format representation of the configuration state."""
if self._defaults:
fp.write("[%s]\n" % DEFAULTSECT)
for (key, value) in self._defaults.items():
fp.write("%s = %s\n" % (key, str(value).replace('\n', '\n\t')))
fp.write("\n")
for section in self._sections:
fp.write("[%s]\n" % section)
for (key, value) in self._sections[section].items():
if key == "__name__":
continue
if (value is not None) or (self._optcre == self.OPTCRE):
key = " = ".join((key, str(value).replace('\n', '\n\t')))
fp.write("%s\n" % (key))
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
#
# Regular expressions for parsing section headers and options.
#
SECTCRE = re.compile(
r'\[' # [
r'(?P<header>[^]]+)' # very permissive!
r'\]' # ]
)
OPTCRE = re.compile(
r'(?P<option>[^:=\s][^:=]*)' # very permissive!
r'\s*(?P<vi>[:=])\s*' # any number of space/tab,
# followed by separator
# (either : or =), followed
# by any # space/tab
r'(?P<value>.*)$' # everything up to eol
)
OPTCRE_NV = re.compile(
r'(?P<option>[^:=\s][^:=]*)' # very permissive!
r'\s*(?:' # any number of space/tab,
r'(?P<vi>[:=])\s*' # optionally followed by
# separator (either : or
# =), followed by any #
# space/tab
r'(?P<value>.*))?$' # everything up to eol
)
def _read(self, fp, fpname):
"""Parse a sectioned setup file.
The sections in setup file contains a title line at the top,
indicated by a name in square brackets (`[]'), plus key/value
options lines, indicated by `name: value' format lines.
Continuations are represented by an embedded newline then
leading whitespace. Blank lines, lines beginning with a '#',
and just about everything else are ignored.
"""
cursect = None # None, or a dictionary
optname = None
lineno = 0
e = None # None, or an exception
while True:
line = fp.readline()
if not line:
break
lineno = lineno + 1
# comment or blank line?
if line.strip() == '' or line[0] in '#;':
continue
if line.split(None, 1)[0].lower() == 'rem' and line[0] in "rR":
# no leading whitespace
continue
# continuation line?
if line[0].isspace() and cursect is not None and optname:
value = line.strip()
if value:
cursect[optname].append(value)
# a section header or option header?
else:
# is it a section header?
mo = self.SECTCRE.match(line)
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(line)
if mo:
optname, vi, optval = mo.group('option', 'vi', 'value')
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:
if vi in ('=', ':') and ';' in optval:
# ';' is a comment delimiter only if it follows
# a spacing character
pos = optval.find(';')
if pos != -1 and optval[pos-1].isspace():
optval = optval[:pos]
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
if not e:
e = ParsingError(fpname)
e.append(lineno, repr(line))
# if any parsing errors occurred, raise an exception
if e:
raise e
# join the multi-line values collected while reading
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)
import UserDict as _UserDict
class _Chainmap(_UserDict.DictMixin):
"""Combine multiple mappings for successive lookups.
For example, to emulate Python's normal lookup sequence:
import __builtin__
pylookup = _Chainmap(locals(), globals(), vars(__builtin__))
"""
def __init__(self, *maps):
self._maps = maps
def __getitem__(self, key):
for mapping in self._maps:
try:
return mapping[key]
except KeyError:
pass
raise KeyError(key)
def keys(self):
result = []
seen = set()
for mapping in self._maps:
for key in mapping:
if key not in seen:
result.append(key)
seen.add(key)
return result
class ConfigParser(RawConfigParser):
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.
"""
sectiondict = {}
try:
sectiondict = self._sections[section]
except KeyError:
if section != DEFAULTSECT:
raise NoSectionError(section)
# Update with the entry specific variables
vardict = {}
if vars:
for key, value in vars.items():
vardict[self.optionxform(key)] = value
d = _Chainmap(vardict, sectiondict, self._defaults)
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 = 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, 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):
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, basestring):
raise TypeError("option values must be strings")
if value is not None:
# 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
if '%' in tmp_value:
raise ValueError("invalid interpolation syntax in %r at "
"position %d" % (value, tmp_value.find('%')))
ConfigParser.set(self, section, option, value)
